Lake and Reservoir Restoration Guidance Manual, 1st Edition

United States
Environmental Protection
Agency
Criteria and Standards Division
Nonpoint Sources Branch
Washington DC 20460
EPA 440/5-88-002
February 1988
The Lake and Reservoir
Restoration Guidance
Manual
First Edition

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Lake and Reservoir Restoration
Guidance Manual
Prepared by the

North American Lake Management Society
Lynn Moore and Kent Thornton, editors
for the

Office of Research and Development
Environmental Research Laboratory
Corvallis, Oregon
and
Office of Water
Criteria & Standards Division
Nonpoint Sources Branch
U.S. Environmental Protection Agency
Washington, D.C.
First Edition
1988 U,S. EmtFOT" • . Section Agency
Region 5, Us, i2J)
77 West Jackson t^ufevard, 12th Floor
Chicago, IL 60604-3590
-------
EPA-440/5-88-002
This Manual has been reviewed by the U.S. Environmental
Protection Agency and approved for publication. Approval does
not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute en-
dorsement or recommendations for use.
The Manual was prepared by the North American Lake Management Society
under EPA Cooperative Agreement No. CR813531-01-0 from the
Environmental Research Laboratory, Corvallis, Oregon.

Cover photograph: Emerald Lake, Colorado
Design and production by Lura Taggart, NALMS
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Preface
The Lake and Reservoir Restoration Guidance Manual represents
a landmark in this nation's commitment to water quality, as it
brings to the lake user practical knowledge for restoring and
protecting lakes and reservoirs. More than an explanation of
restoration techniques, this Manual is a guide to wise manage-
ment of lakes and reservoirs.
Congress recognized the need for compiling this information
and communicating it to the community level, as the logical out-
growth of the Clean Lakes Program established by the Clean
Water Act of 1972. For the past 17 years, the Clean Lakes
Program has given states matching grants to restore degraded
lakes. That process has generated a great deal of information
about what techniques to use in restoring these water bodies,
how and where they should be used, and how well they work.
This Manual is the first step in making that information available in
a comprehensive, organized format.
As the Manual was being written, Congress continued its effort
to improve this knowledge base by mandating in the Water
Quality Act of 1987, that this Manual be updated every two years.
The purpose of the Manual is to provide guidance to the lake
manager, lake homeowner, lake association and other informed
laypersons on lake and reservoir management, restoration and
protection. With this in mind, the reader is invited to send com-
ments and suggestions to the Clean Lakes Program, Nonpoint
Sources Branch (WH-585), U.S. Environmental Protection Agen-
cy, 401 M Street, S.W., Washington, DC 20460.
in
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Contents
Preface
Content
Acknowledgements ........................... Xi
Contents ................................... v
Chapter 1: Overview of Manual
Introduction 1.1
Audience 1_1
Focus -j.2
Lakes as Resources 1 _2
Natural Lake Conditions 1.2
Desired Lake Uses •) .3
What a Lake IS NOT ^3
Defining Desired Uses 1_4
User Involvement -(.4
Causes versus Symptoms - A Major Reason for This Manual .... 1-4
Manual Organization -|_5
Definitions -j.g
Chapter 2: Ecological Concepts
Lake and Reservoir Ecosystems 2-1
The Lake and Its Watershed 2-3
Water 2-3
Special background section: The Hydrologic Cycle 2-4
Special background section: Hydraulic Residence Time 2-5
Dissolved Materials 2-5
Particulates 2-7
Effects of Lake Depth 2-7
Man-Made Lakes 2-8
Lake Processes 2-8
Lake Stratification and Mixing 2-8
Mixing Processes 2-8
Water Movements 2-10
Organic Matter Production and Consumption 2-11
Photosynthesis and Respiration 2-11
Special background section: The Unique Properties of Water ... 2-12
Phytoplankton Community Succession 2-15
Sedimentation and Decomposition 2-16
Food Web Structure, Energy Flow, and Nutrient Cycling 2-17
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Lake Aging and Cultural Eutrophication 2-19
Special background section: Lake Basin Origin and Shape 2-20
Ecology's Place in Protection and Restoration 2-22
Summary 2-23

Chapter 3: Problem Identification
Chapter Objectives 3-1
Common Lake Problems 3-1
Algae 3.4
Weeds 3.4
Depth 3.4
User Conflicts 3.4
Problem Statement 3.5
Problem Identification 3.5
Problem Perception 3.5
Causes of Lake Problems 3-6
Selecting a Consultant 3.7
Problem Diagnosis 3.7
Investigate the Problem 3.7
Preliminary Analyses 3.9
Data Collection and Analyses 3-11
Water Budget 3-11
Surface Water and Lake Level 3-11
Groundwater Measurements 3-12
Water Quality Monitoring 3-14
Sampling Sites 3-14
Physical Parameters 3-15
Sedimentation Rate Estimates 3-15
Temperature 3-15
Transparency 3-16
Chemical Parameters 3-17
Dissolved Oxygen 3-17
Nutrients 3-18
Biological Parameters 3-19
Algal Biomass 3-19
Macrophyte Biomass and Locations 3-19
Use of Trophic State Indices 3-21
Problem Definition 3-23
Putting the Pieces of the Puzzle Together 3-23
Mirror Lake 3-24
VI
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Chapter 4: Predicting Lake Water Quality
Uses of Models 4_1
Eutrophication Model Framework 4.3
Variability 4.5
Loading Concept 4.5
Water Budget 4.7
Phosphorus Budget 4.3
Lake Response Models 4_12
Tracking Restoration Efforts 4-16
Lake Washington, Washington: "You Should Be So Lucky1 4-18
Onondaga Lake, New York: "Far Out. 93 Percent Is Not Enough" 4-18
Long Lake, Washington: "What's This? Reservoir Restoration?" . . . 4-20
Shagawa Lake, Minnesota: 'The Little Lake That Couldn't" 4-20
Kezar Lake, New Hampshire: "The Little Lake That Could (With a Little
Help)", or "Shagawa Revisited ..." 4_2o
Lake Morey, Vermont: "Strange Mud ..." 4-21
Wahnbach Reservoir, Germany: "When All Else Fails ..." 4-22
Lake Lillinonah, Connecticut: "You Can't Fool Mother Nature..." . 4-22

Chapter 5: Managing the Watershed
Introduction 5_1
The Lake-Watershed Relationship 5.1
Point Sources 5_2
Wastewater Treatment 5.3
Choosing the Scale of the System 5.3
Municipal Systems 5.3
Small-Scale Systems 5.4
On-lot Septic Systems 5.5
Community Treatment Facilities 5.3
Water Conservation to Reduce Lake Problems 5-11
How to Assess Potential Sources 5-12
Assessing Point Sources 5.13
Nonpoint Sources 5_13
Cultural Sources of Sediments, Organic Matter, and Nutrients 5-14
What are Best Management Practices? 5-15
Lake Restoration Begins in the Watershed 5-17
Guidelines and Considerations 5.19
Examples of Point and Nonpoint Improvement Projects 5-20
Lake Washington: Point Source Diversion 5-20
Annabessacook Lake, Cobbossee Lake, and Pleasant
Pond: Point-Source Diversion/Nonpoint Source Waste
Management/I n-Lake Treatments 5-20
East and West Twin Lakes: Septic Tank Diversion 5-21
vii
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Chapter 6: Lake and Reservoir Restoration and
Management Techniques
Introduction 6-1
The Principles of Restoration e-1
Are Protection and Restoration Possible? 6-2
Lake and Reservoir Restoration and Management Techniques 6-4
Basic Assumptions 6-4
Problem I: Nuisance Algae 6-5
Biology of Algae 6-5
Algae/Techniques with Long-Term Effectiveness 6-5
Phosphorus Precipitation and Inactivation 6-5
Sediment Removal 6-7
Dilution and Flushing 6-10
Algae/Additional Procedures for Control 6-11
Artificial Circulation 6-11
Hypolimnetic Aeration 6-12
Hypolimnetic Withdrawal 6-13
Sediment Oxidation 6-14
Food Chain Manipulation 6-14
Algicides 6-17
Algae/Summary of Restoration and Management Techniques 6-18
Problem II: Excessive Shallowness 6-18
Problem III: Nuisance Weeds (Macrophytes) 6-19
Biology of Macrophytes 6-19
Macrophytes/Long-Term Control Techniques 6-20
Sediment Removal and Sediment Tilling 6-20
Water Level Drawdown 6-22
Shading and Sediment Covers 6-23
Biological Controls 6-24
Macrophytes/Techniques with Shorter-Term Effectiveness 6-28
Harvesting 6-28
Herbicides 6-30
Macrophytes/Summary of Restoration and Management Techniques . . 6-34
Problem IV: Eutrophic Drinking Water Reservoirs 6-35
Nature of the Problem 6-35
Water Supply Reservoir Management 6-35
Color 6-36
Taste and Odor 6-36
Loss of Storage Capacity 6-36
Trihalomethane Production 6-36
Problem V: Fish Management 6-37
Nature of the Problem 6-37
Diagnosis and Management 6-37
VIM
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Chapter 7: Hypothetical Case Study

Purpose Of Case Study 7-1
Lynn Lake-a Case Study 7-1
Problem Definition 7-3
Lake Restoration Advisory Committee 7-5
Consultant Selection 7-6
Detailed Work Plan 7-7
Phase I Grant Application 7-8
Lake And Watershed Study 7-8
Study of Lake and Watershed Characteristics 7-8
Study of Previous Uses and Recreational Characteristics 7-9
Lake Monitoring 7-9
Watershed Monitoring 7-11
Data Analysis 7-14
Lake Analysis 7-14
Watershed Analysis 7-16
Evaluation of Management Alternatives 7-18
Evaluation Criteria 7-18
Effectiveness 7-19
Longevity 7-20
Confidence 7-20
Applicability 7-20
Potential for Negative Impacts 7-21
Capital Costs 7-21
Watershed Management Alternatives 7-23
Wastewater Treatment Plant Upgrade 7-24
Sedimentation Basins 7-24
Agricultural Practices 7-24
Construction Controls 7-26
In-lake Management Alternatives 7-26
Public Hearing 7-29
Selection of Management Plan 7-29

Chapter 8: Implementing the Management Plan
Management Means Implementation 8-1
Who Does the Work? 8-1
Selecting Consultants or Contractors 8-2
Institutional Permits, Fees, And Requirements 8-3
Implementation Costs Money 8-8
Plans and Specifications 8-8
Funding Sources 8-8
Federal Agencies 8-8
State Agencies 8-9
Local Sources 8-10
IX
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Implementation Requires Contracts 8-10
Implementation Takes Time 8-11
Public Education Is Critical For Sound Lake Management 8-11
Post Monitoring Is An Integral Part Of Implementation 8-12

Chapter 9: Lake Protection And Maintenance
Introduction g.1
Lake Organizations 9-1
Regulations In Lake and Watershed Protection And Management 9-2
Controlled Development g_2
Permits and Ordinances 9.5
Lake Monitoring 9.7
Epilogue 1(M
References 10-3
Index 10_7

Appendices
Appendix A: Metric Units A-1
Appendix B: Glossary B-1
Appendix C: Point Source Techniques C-1
Appendix D: Best Management Practices D-1
Appendix E: State/Provincial Lake Management Information E-1
Appendix F: Forms and Documents F-1
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Acknowledgements
This Guidance Manual was prepared under the guidance of Kent W. Thornton,
Ph.D., Project Manager, NALMS. The authorship for each chapter includes:

CHAPTER 1: OVERVIEW OF MANUAL
Kent W. Thornton, Ph.D.
FTAMssoc/ates
CHAPTER 2: ECOLOGICAL CONCEPTS
Bruce Kimmel, Ph.D.
Oak Ridge National Laboratory

CHAPTER 3: PROBLEM IDENTIFICATION
Lowell Klessig, Ph.D.
University of Wisconsin-Stevens Point
Richard Wedepohl, Ph.D.
Douglas Knauer, Ph.D.
Wisconsin Department of Natural Resources

CHAPTER 4: PREDICTING LAKE WATER QUALITY
William W. Walker, Ph.D.
Environmental Consultant

CHAPTER 5: MANAGING THE WATERSHED
KentW. Thornton, Ph.D.
Forrest E. Payne, Ph.D.
FTN Associates

CHAPTER 6: LAKE AND RESERVOIR RESTORATION AND
MANAGEMENT TECHNIQUES
Dennis Cooke, Ph.D.
Kent State University

CHAPTER 7: HYPOTHETICAL CASE STUDY
Frank X. Browne, Ph.D.
F.X. Browne Associates

CHAPTER 8: IMPLEMENTING THE MANAGEMENT PLAN
William Funk, Ph.D.
Washington State University

CHAPTER 9: LAKE PROTECTION AND MAINTENANCE
Kent W. Thornton, Ph.D.
F7AMssoc/ates
XI
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The document was extensively reviewed by Lynn Moore, Garth Redfield,
Ph.D., Chair, NALMS Editorial Board, Wayne Poppe, Ph.D., Spencer Peterson,
Ph.D., Kent W. Thornton, Ph.D. and Dennis Cooke, Ph.D. The document was
reviewed by both technical and lay persons and review comments were received
from:

Val Smith, Ph.D. William Jones
University of North Carolina Indiana University

Chris Holdren, Ph.D. Lucy Scroggins
University of Louisville City of Hot Springs

Dennis Bokemeier Jonathan Simpson
Lake Sommerset Property Candlewood Lake
Owners Association Association

Donna Sefton Don Roberts
Sfafe of Illinois U.S. EPA-Region V

Jerri Hollingsworth William Morris
U.S. EPA Albemarle County, Virginia

Walter Shannon, Jr.
Lakeville, Connecticut

All of these individuals are gratefully acknowledged for their efforts and con-
tributions to this Guidance Manual. The authors are particularly commended for
their tireless effort in preparing this manual.
xii
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CHAPTER 1
Overview of Manual
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CHAPTER 1
OVERVIEW OF MANUAL
Introduction
This Guidance Manual pursues a very broad subject — protecting and restoring
lakes and reservoirs. An enormous amount of information trails behind that
topic. The burden on those who wrote this Manual was not in finding good
material to put in, but in deciding where to stop. To make a book so full of infor-
mation that it deserves premier shelf space for its reference value but remains
compact enough to lift easily required some guiding assumptions.
First, this Manual supplies its own context. Therefore, any point the reader
finds in midbook is prefaced with adequate background information to under-
stand it and then followed with guidance on how to apply it. The material
presented here was chosen because it fits a fourfold purpose:
1. To help users identify, describe, and define their lake problems '
2. To help them evaluate available lake and watershed management practices
for addressing problems or protecting current quality
3. To describe the process of developing a site-specific lake or reservoir
management plan
4. To illustrate how to put a lake management plan into practice and evaluate
its effectiveness
Audience

This Manual is written for the informed citizen who is interested in lakes and
reservoirs - in protecting, restoring, and managing them. It is not written for the
scientist or engineer. Consequently, English units of measure are used here, ex-
cepting a few terms that are never reported in English units. Appendix A
provides the reader with information on the metric system. Many other, more
technical, documents discuss specific points of lake and reservoir management
in detail. Additional references and sources of information are given wherever
appropriate.
1-1
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Focus

The focal point of this book is water quality, particularly the effects of excessive
inputs of silt, nutrients, and organic matter known as eutrophication. The reader
will find information here on the effects of water quality on fish, for example, but
will need another source for advice on fisheries management. State game and
fish agencies, the U.S. Fish and Wildlife Service, the U.S. Soil and Conservation
Service, and other agencies publish numerous booklets, fact sheets, and techni-
cal bulletins on fish management that more than suffice for this omission.
Technical jargon is kept to a minimum to help the reader grasp important
points without stumbling over the words. Even so, a handful of terms are so im-
portant to lake management that working around them would be a disservice.
These terms are defined in a side note the first time that they appear, clearly ex-
plained in the text, and included in the glossary. The only word that needs some
advance explanation is the relatively simple word, lake. It is used genetically in
this Manual to include both natural lakes and reservoirs. Distinctions between
the two types of systems are discussed when these distinctions have important
management implications.
Lakes as Resources
Lakes are important resources on our landscapes. As sources of enjoyment,
they support fishing, boating, and swimming. Fishing and swimming are among
the fastest growing and most popular forms of outdoor recreation in the United
States and Canada. Lakes' commercial value in food supply, tourism, and
transporation is worth many billions of dollars each year. Lakes also provide life-
sustaining functions such as flood protection, generation of electricity, and sour-
ces of drinking water. Finally, as places of beauty, they offer solitude and
relaxation. This aesthetic quality is not a minor gift - over 60 percent of Wiscon-
sin lake property owners who were asked what they valued in lakes rated aes-
thetics as especially important.

Natural Lake Conditions

The natural condition of a lake - before home construction, before deforesta-
tion, before agriculture and other human activities — may not have been nearly
as pristine as is commonly believed. The natural geologic process is for lakes of
moderate depth to gradually fill and become wetlands. The position of a lake
along this geologic continuum from deep to shallow influences the natural water
quality that might be expected in a lake.
Many lakes would be eutrophic despite human activities and development in
the watershed. In the Southern United States, for example, soil fertility, runoff
patterns, and geology encourage a somewhat more eutrophic natural condition
compared to Northern lakes. Northerners expecting to see deep blue waters
may find the color of healthy Southern lakes dismaying. Even comparing nearby
lakes may be misleading because the lakes may differ in critical ways - depth,
water source, erodibility of watershed soils, comparative watershed size, and
local land use. Major differences can occur from one side of town to the other or
across a State. For example, changes in lake quality from northern to southern
Wisconsin or from eastern to western Minnesota reflect regional differences in
these factors.
1-2
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Such differences need to be factored into lake management. Because the
natural lake water quality obviously affects lake uses, an important goal of both
this Manual and lake management is to identify and define the uses a lake could
naturally support and to develop a compatible lake and watershed management
plan to restore the lake to this natural condition or protect its current condition.
This variability brings up a key point in lake management: Whatever the start-
ing conditions and whatever the limitation on what can ultimately be achieved,
the goal is always the same - to minimize lake quality problems. '

Desired Lake Uses

Lake usage is a match between people's desires and the lake's capacity to satis-
fy these desires. Lake problems are defined in terms of the limits on desired uses
- as limitations on uses that can reasonably be prevented or corrected with
proper management. This is a critical definition for developing lake management
programs: A lake problem is a limitation on the desired uses by a particular set
of users. Before undertaking a management program, these desired uses need
to be clearly defined, limitations on the uses must be identified, and the causes
must be understood.

What a Lake IS NOT

A lake cannot be all things to all people. Desirable uses, even obtainable ones,
can conflict. Lake organizations invariably would like to see their lake do every-
thing. They want aesthetic pleasure, great fishing, healthy water, sandy
shorelines and bottoms, and a nice wildlife population - all without pests, in-
sects, or weeds. Unfortunately, almost no lake can meet all of these demands.
Depending on physical characteristics of the lake basin and watershed and
the quality of incoming water, lakes are suited to particular uses. Even when a
lake is capable of several uses, however, management for a specific use may
still be required. Like cattlemen and sheepherders, motor boaters and trout
fishermen don't necessarily get along.
Although it might be technically possible to drastically alter a lake to meet the
needs of a particular user group, the cost will be high and the decision is usually
unwise. It is important to understand a lake's capacity and attainable quality
when developing a management plan to obtain certain desired uses. Some
lakes will never be crystal clear. No matter what restoration or management
measures are taken, if the drainage area is large relative to lake surface area and
the soils are highly erodible and nutrient-rich, the lake will promptly return to its
former state. Even the most reliable restoration techniques are not universally
appropriate. The same procedure that improves lake quality in one lake can
diminish it in another. For example, a technique called artificial circulation can
decrease algal problems in some lakes but may increase algal production in
others.
This Manual concentrates on how to determine what uses the lake can sup-
port with reasonable management efforts. It is critical, therefore, to determine,
what lake uses are desired and have these goals clearly in mind and in focus as
the problems are delineated.
1-3
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Defining Desired Uses
While user groups obviously are the prime candidates for identifying desirable
goals, they often lack sufficient understanding to assess the practicality of their
wishes. The material in this Manual will be helpful in examining the feasibility of
proposed goals. In addition, the advice of experts is highly recommended. Many
State and Federal sources are available, and they are listed in later chapters of
this Manual.

User Involvement

Lake and reservoir management is an active process. Informed citizens must be-
come involved if desired and attainable lake uses are to be achieved. Getting
people together and simply finding out what they want may require as much ef-
fort as figuring out how to do it. Since a given lake may serve several different
groups of users, several different methods might be required to involve all of
these major user groups.
Lake homeowners and other local users can get involved with lake use
decisions through membership in one of several types of lake organizations. The
local powers and financial ability of these groups vary considerably from com-
munity to community and State to State. (See Chapter 8 for additional discus-
sion of legal authority and issues). Also, the annual meeting of the local lake
group is an obvious place to discuss and vote on priority uses for the lake. If the
lake serves primarily local property owners and residents, such votes are likely
to be respected by government agencies.
Reaching a consensus on specific lake uses may be difficult, however, if more
than one lake organization exists on the lake, especially if conflicting uses are al-
ready well established.
There are several procedures or approaches that can be used to reach a con-
sensus on desired lake uses and identify various lake problems. These ap-
proaches, described in Appendix 3-A, include the nominal group process and
the Delphi process. While these techniques can be very effective when properly
used, most lake managers or informed citizens will need professional assistance
in using them. Lake associations typically include people of diverse occupations,
however, so a member of the association may have the experience needed to
use these methods.
Based on the beginning definition - a lake problem is a limitation on the
desired uses by a particular set of users - defining the desired lake uses and
the limitations on these uses represents the cornerstone of any lake manage-
ment program.

Causes Versus Symptoms - A Major

Reason for This Manual

The greatest bias of lake users, in general, is confusing the symptoms of
problems with their causes. Most lake communities need professional help to
identify causes of lake problems. To decide when professional advice is war-
ranted and how much help is needed, local lake community leaders need to un-
derstand lakes in general and be aware of possible causes of the problems. The
purpose of this Manual is to help the user define problems, understand the un-
derlying causal mechanisms, evaluate available techniques for addressing
problems, develop an effective lake management plan, solve problems by im-
plementing this plan, and evaluate the plan's effectiveness.
1-4
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In most cases, managing or restoring a lake eventually requires help from a
professional lake manager, limnologist, or environmental engineer. This Manual
provides guidance for selecting consultants and for finding appropriately
qualified experts.
Manual Organization

The Manual is divided into three parts.

Part 1 - Understanding and Defining the Problem

Chapter 2 provides information on how inseparably lakes and watersheds are
coupled and how lakes function as systems. It is important to have some under-
standing of how the various components of a lake and watershed work and fit
together. It doesn't take a mechanic to drive a car, but any driver needs to un-
derstand what makes the car go and what makes it stop in general principle. The
eutrophication process can be accelerated or slowed down by various manage-
ment techniques and their effects on the different lake components. This chapter
describes these processes.
Chapter 3 describes the process used to identify the lake problem and dif-
ferentiate symptoms from causes. This is a critical part of lake management.

Part 2 — Management Techniques

Chapter 4 discusses analytical tools available for evaluating the potential effec-
tiveness of lake and watershed management techniques in achieving a desired
lake use or certain level of lake quality.
Chapter 5 discusses the effects of watershed land use on lake quality and
various watershed management techniques available to control point and non-
point source pollutants entering the lake.
Chapter 6 discusses in-lake management techniques available to achieve a
desired lake use. It focuses not only on the techniques but also on their mode of
action and possible interactions with other techniques.

Part 3 — Development and Implementation of a
Lake Management Plan

Chapter 7 describes how the watershed and lake management techniques are
integrated to formulate and develop an effective lake management plan. The
procedure is illustrated through the use of a comprehensive example - a
hypothetical case study.
Chapter 8 discusses putting the lake management plan into practice. This re-
quires attention to numerous practical details such as permits, bonding, in-
surance, and scheduling.
Chapter 9 discusses how to protect the current lake quality or the lake quality
after restoration. Lake organizations and associations can be effective forces in
protecting lakes. Monitoring the lake status and changes occurring in the lake is
the keystone of lake management and protection.
Appendices and a glossary supplement the material covered in Chapters 1
through 9. Appendix A, on the metric system, will be especially useful to the
reader who is not comfortable with the metric units.
1-5
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As mentioned earlier, lake management is an active process. Informed
citizens are invaluable to this process. The purpose of this Manual is to help
those who have an interest in lakes achieve the primary goal of lake manage-
ment: to realize whatever desirable uses a particular lake has the capacity to
support.
Definitions
Terms important to the understanding of lake management are defined in the
margins beside their first appearance in the text.
1-6
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CHAPTER 2
Ecological Concepts
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CHAPTER 2
ECOLOGICAL CONCEPTS

Lake and Reservoir

Ecosystems

Lake management must be based on an understanding that lakes are complex
and dynamic ecosystems.
The lake, viewed simply as a water system, is influenced by a set of
hydro-logic conditions, the watershed, the shape of the lake basin, the lake
water, and bottom sediments. These physical and chemical components of the
lake system, in turn, support a community of organisms that is unique to the lake
environment. The lake biota enrich the complexity of the lake system; they not
only have a myriad of links to one another but also affect the lake's physical and
chemical features (Fig. 2-1). All of these components of the lake system-physi-
cal, chemical, and biological-are in constant change, and the chemical and
biological components are particularly dynamic.
Because lakes are highly interactive systems, it is impossible to alter one
characteristic, such as the amount of weeds or the clarity of the water, without
affecting some other aspect of the system, such as fish production. For ex-
ample, a lake association might decide to remove all weeds by mechanical
processes, accidentally destroying important habitat needed for fish survival. In
addition, algae might proliferate, fed by some of the nutrients the weeds had pre-
viously used. If the lake association then decided that a chemical treatment
would solve the algae problem and help clear up the water, the next sequence in
the chain of events might be more penetration of sunlight through the water,
which could encourage new weed growth, which could affect fish survival.
Ecology is the scientific study of the interrelationships among organisms and
their environment. Managing a lake for maximum benefit requires an under-
standing of how lake ecosystems are structured and how they function. The ex-
ample just given is hypothetical, but variations on these unexpected results
happen over and over across the country when management programs are im-
plemented without adequate knowledge of lake ecology.
Ecosystem: A system of in-
terrelated organisms and
their physical-chemical en-
vironment. In this manual,
the ecosystem is usually de-
fined to include the lake and
its watershed.
Biota: All plant and animal
species occurring in a
specified area.
Ecology: Scientific study of
relationships between or-
ganisms, and their environ-
ment. Also, defined as the
study of the structure and
function of nature.
2-1
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Marginal zone
Littoral zone
Pelagic zone

Profundal zone
Pelagic zone (open water)
Benthic zone
Figure 2-1.-The location and nature of typical lake communities, habitats, and organisms.
In addition to the lake's watershed, all of these components are part of the lake ecosystem.
2-2
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The hypothetical example also illustrates a confusion between causes and
symptoms. Not only did the association fail to think about how lake organisms
were related to one another, they also failed to ask why weeds and algae were
growing profusely. Limnology is the scientific study of freshwater ecosystems:
lakes, reservoirs, rivers, and streams. The goal of limnology is to improve the un-
derstanding of physical, chemical, geological, and biological factors that affect
aquatic productivity and water quality. An adequate understanding of limnology
is the backbone of sound lake management.
This chapter is not intended to be a text on either aquatic ecology or limnol-
ogy. Rather, its goal is to provide to the reader the background information
necessary to understand the causes of lake degradation problems and identify
the lake management and restoration approaches that are most applicable to
their particular situation.
The Lake and Its Watershed
Lakes are constantly receiving materials from their watersheds and from the at-
mosphere, and energy from the sun and wind. Because of this, lake quality is as
much influenced by what can (and will) go into the lake as it is by what is already
there. The lake is a receiver, and what comes into it depends largely on existing
conditions in the surrounding watershed. Important factors include watershed
topography, local geology, soil fertility and erodibility, vegetation in the water-
shed, and other surface water sources such as runoff and tributary streams. The
atmosphere may contribute materials to the lake as well, notably acidity from
rainfall and dust in some areas. See the special section on the hydrologic cycle,
which describes major natural phenomena controlling water supply.
Three basic items enter the lake from its watershed: water, dissolved
materials carried in water, and particulates such as soil.
Watershed: A drainage
area or basin in which all
land and water areas drain
or flow toward a central col-
lector such as a stream,
river, or lake at a lower ele-
vation.
Water

The amount of water entering the lake from its watershed controls lake volume
and several other factors that influence the lake's overall health. A lake, like any
tank, takes a predictable amount of time to fill and to empty, given a certain rate
of flow. Unlike rivers, lakes essentially slow the flow of water; thus, any water
entering the lake will remain in it for a period called the hydraulic residence time
(see Special Section). The lake water quality reflects the history of the lake
water, as well as the condition of new incoming water.
Because of this residence time, management programs directed at improving
lake water quality by improving incoming water will face a lag period between
the time that incoming water quality gets better and the time that change be-
comes evident in the lake. The longer the residence time, the greater the lag.
Additional delays between changes in the quality of incoming water and that
of in-lake water will also occur because water affects and is affected by the biota,
sediments, and existing water chemistry.
2-3
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The Hydrologic Cycle

Because the amounts of precipitation and surface water runoff directly in-
fluence the nature of lake ecosystems, a good way to begin to learn about
lakes is to understand the water or hydrologic cycle. The circulation of
water from atmosphere to earth and back to the atmosphere is a process
which is powered by the sun (Fig. 2-A). Worldwide, about three-fourths of
the precipitation received on the land is returned to the atmosphere as
water vapor via evaporation and transpiration from terrestrial and emer-
gent and floating aquatic plants. The rate of evaporation and transpiration
varies with factors such as wind speed and amount of insolation. The
remaining precipitation either is stored in ice caps, or drains directly off
the land and into surface water systems such as streams, rivers, lakes, or
oceans, from which it eventually evaporates, or it infiltrates the soil and
underlying rock layers and enters the groundwater system. Groundwater
flows may enter lakes and streams through underwater seeps or springs
or surface channels, and then return to the atmosphere via evaporation.
INFILTRATION

GROUND WATER FLOW
WATER TABLE
Figure 2-A.-Hydrologic cycle.

Lakes and reservoirs have a water "balance," described as this simple
equation: water input = water output +/- the amount of water stored in
the lake. Inputs are direct precipitation, groundwater, and surface
streams, while outputs are surface discharge (outflow), evaporation, los-
ses to groundwater, and water withdrawn for domestic-agricultural-in-
dustrial purposes. Sometimes inputs are greater than outputs, and lake
levels rise as water is stored. At other times, for example, a summer
drought, lake levels fall as losses exceed gains.

Some lakes, called seepage lakes, are formed at the intersection of the
groundwater flow system with the land surface. Seepage lakes are main-
tained primarily by groundwater inflow, and their water levels fluctuate
with seasonal variations in the local water table. Drainage lakes, on the
other hand, are fed primarily by inflowing rivers and streams, and their
water levels vary with the surface water runoff from their surrounding
watersheds. In both cases, the balance between hydrologic inputs and
outputs influences the nutrient supply to the lake, the lake's water
residence time, and consequently the lake's productivity and water
quality.
2-4
-------
Hydraulic Residence Time
The average time required to completely renew a lake's water volume is
called the hydraulic residence time. For instance, it might take 5 minutes
to completely fill a bathtub with the tap fully open and the bottom drain
closed. The hydraulic residence time of the tub, then, is 5 minutes. With
the tap and drain only half open, the hydraulic residence time would be 10
minutes.
tat
Inflow =
10 gal/mm
Ib)

Inflow =
10 acre-ft/day
Outflow =
1" acre-ft/day
Outflow =
10 gal/min
Hydraulic residence time = Volume 7 Flow Rate
= 50 gal ; 10 gal/min = 5 min
Water residence time = 500 acre-ft T 10 acre-ft/day
= 50 days
Figure 2-B.-Hydraulic residence time is an important factor to consider in restoration
programs. The simple formula given in the figure assumes that inflow is equal to
outflow.

If the lake basin volume is relatively small and the flow of water is relative-
ly high, the hydraulic residence time can be so short, less than 10 days for
example, that algal biomass is not accumulated in the lake. The algal cells
produced in the water column are washed out faster than they can grow
and accumulate.

An intermediate water residence time permits both an abundant supply of
plant nutrients and adequate time for algae to assimilate nutrients and to
grow and accumulate.

Longer water residence times from 100 days to several years provide
plenty of time for algal biomass to accumulate, if there are sufficient
nutrients present. The production of algae may ultimately be limited by
the supply of nutrients. If the nutrient supply is high, algal biomass will be
very large. The combined effects of nutrient income or "nutrient loading"
and hydraulic residence time on the production of algae is the basis for
methods to predict changes in the condition of the lake following changes
in one or both of these processes (such as the diversion of wastewater
flows.) This will be discussed in Chapter 4.
Dissolved Materials
One of the most important materials dissolved in water is oxygen. Sources of
dissolved oxygen include inflowing water, transfer from the atmosphere (gas ex-
change), and production by aquatic plants. Oxygen production by plants is dis-
cussed later in this chapter. Oxygen is consumed or removed from the lake by
outflow, loss to the atmosphere, nonbiological combination with chemicals in
the water and mud (chemical oxygen demand, or COD), or plant, bacterial, and
animal respiration. Biochemical oxygen demand (BOD) is a common measure
used to describe the rate of oxygen consumption by organisms and materials
Chemical oxygen demand
(COD): Nonbiological up-
take of molecular oxygen by
organic and inorganic com-
pounds in water.
2-5
-------
under dark conditions, and varies with the amount of organic matter and
microbes in the water. Wastewater discharges can have very high BOD, for ex-
ample.
When the loss of oxygen from the water exceeds the input of oxygen from
various sources, the oxygen content of the lake water is decreased. If the dis-
solved oxygen becomes severely depleted, anoxic conditions can occur that
lead to odors, fishkills, increased phosphorus and ammonia concentrations, and
other undesirable effects.
Inflowing stream water also carries the two principal plant nutrients, nitrogen
and phosphorus, in both dissolved organic and inorganic forms. Nitrogen and
phosphorus are required for the biological production of phytoplankton (free-
floating microscopic algae) and macrophytes (larger, floating and rooted plants
or "weeds"). (See the section in this chapter on Organic Matter Production and
Consumption.) Surface and subsurface drainage from fertile (nutrient-rich)
watersheds results in biologically productive lakes, and drainage from infertile
(nutrient-poor) watersheds results in biologically unproductive lakes.
Soils, weathered minerals, and decomposing organic matter in the watershed
are the main natural sources of phosphorus and nitrogen. Man-made sources
such as agriculture, crop and forest fertilizers, and wastewater discharges,
however, commonly increase the rate of nutrient income or loading from water-
sheds and are the major causes of biological overproduction in many lakes (see
Table 2-1). Watershed disturbances such as logging and mining, which remove
the land's natural vegetation, can greatly increase the amount of silt and
nutrients exported from the land to the lake. Chapter 5 discusses the effects of
watershed disturbance in greater detail, along with management practices to
control sediment and nutrient loads from the watershed to the lake. Finally,
some pesticides, herbicides, toxic pollutants, chemicals in wastewater dischar-
ges, and industrial waste materials also enter the lake with incoming water.

Table 2-1.—Representative values for nutrient export rates and input rates for
various land uses. All values are medians and are only approxima-
tions owing to the highly variable nature of data on these rates.
LAND USE TOTAL PHOSPHORUS TOTAL NITROGEN
A. Export rates (kg/ha/yr)1'2
Forest 0.2 2.5
Nonrow crops 0.7 6.0
Pasture 0.8 14.5
Mixed agriculture 1.1 5.0
Row crops 2.2 9.0
Feedlot, manure storage 255.0 2920.0

B. Total atmospheric input rates (kg/ha/yr)1'3
Forest 0.26 6.5
Agricultural/rural 0.28 13.1
Urban industrial 1.01 21.4

C. Wastewater input rates (kg/capita/yr)4
Septic tank input5 1.45 4.65
' Values in this table are all in kg/ha/yr, which is the standard for such measurements To convert to pounds per acre per year,
multiply by 0 892
2 Source Reckhow et al 1980, Figure 3
3 Source Reckhow et ai 1980, Table 13
4 Source Reckhow et al 1980, Table 14
5 This is prior to absorption to soil during infiltration, generally, soils will absorb 80 percent or more of this phosphorus
2-6
-------
Particulates

Organic matter, clays, and silt wash from the watershed and into the lake. Where
the land is disturbed, the loss of soil is apt to be very high. Even removing brush
and replacing it with a poor stand of lawn increases the rate of erosion.
Erodibility among soil types varies and is one of the factors that must be con-
sidered in watershed management programs. In addition to soil loss from the
land via rainfall and snowmelt, streams may scour soil from their banks as they
flow. Wind also carries some particulates such as dust and pollen directly to
lakes. Inputs of suspended particles result in increased turbidity (a decrease of
water transparency and light availability, which affects plant growth).
Lakes are extremely efficient sediment traps. Filling in with silt is part of a
lake's natural aging pattern, but poor land management practices can speed up
the process significantly. Suspended sediment particles that can be easily car-
ried by rivers and streams settle out once they reach the relatively quiescent lake
environment. As a consequence of this trapping ability, particle-associated
nutrients, organic matter, and toxic contaminants are often retained in lake
basins.
Many toxic contaminants become strongly associated with (adsorbed to)
suspended particles. The influx of herbicides, pesticides, and toxics adhered to
soil particles is becoming an increasingly common problem for lakes. Incoming
silt can bring other problems as well. Silt-laden water can reduce light penetra-
tion and, consequently, the light available to algae. Many species of fish are
sight feeders; they cannot locate prey efficiently in muddy waters. Silt deposits
can prevent successful hatching of fish eggs that require clean surfaces. Finally,
excessive levels of silt can irritate fish.
The section in this chapter on Sedimentation and Decomposition discusses
the effect of organic matter in the water on dissolved oxygen. Particles of or-
ganic matter can enter the lake from watershed runoff, can be suspended in
tributary streams, or can originate within the lake itself from the aquatic plants
and animals. Chapter 3 discusses the use of radioisotopes to date sediment
deposition in the lake. Controlling soil loss from the watershed is treated in
Chapter 5 in the discussion of best management practices. The use of dredging
to deepen a lake and remove sediments is discussed in Chapter 6.
Effects of Lake Depth

Shallow lakes tend to be more biologically productive than deep lakes because
of the large area of bottom sediments relative to the volume of water, more com-
plete wind mixing of the lake water, and the large very shallow or littoral areas
along the lake perimeter that can be colonized by rooted and floating macro-
phytes. Indeed, shallow lakes may be dominated by plant production in littoral
areas and have little open-water habitat. Large incomes of silt and incomplete
decomposition of macrophytes can make lakes become shallow rapidly. Usual-
ly, shallow lakes also have a shorter hydraulic residence time.
Deep, steep-sided lakes usually stratify thermally during the summer, which
prevents complete mixing of the lake water. These lakes may have less area that
is shallow enough for rooted aquatic plants to receive light and grow. Thus,
deep lakes generally have a high proportion of open-water (pelagic) habitat, and
their food webs tend to be based on the organic matter produced by algae, or
planktonic plants. Many reservoirs have large areas of shallow water, but flood
control operations often bring about water-level fluctuations that discourage
well-developed stands of aquatic weeds along the shoreline.
Organic matter: Molecules
manufactured by plants and
animals and containing
linked carbon atoms and el-
ements such as hydrogen,
oxygen, nitrogen, sulfur,
and phosphorus.
Sediment: Bottom material
in a lake that has been de-
posited after the formation
of a lake basin. It originates
from remains of aquatic or-
ganisms, chemical precipi-
tation of dissolved miner-
als, and erosion of sur-
rounding lands (see ooze).
Littoral zone: That portion
of a water body extending
from the shoreline lakeward
to the greatest depth occu-
pied by rooted plants.
Pelagic zone: This is the
open area of a lake, from
the edge of the littoral zone
to the center of the lake.
2-7
-------
Man-Made Lakes

In contrast to the glacial lakes that may be thousands of years old, most man-
made impoundments have been constructed within the past 100 years. Ponds,
stock tanks, and small reservoirs have been formed for agricultural use,
municipal water supply, soil and water conservation, and recreation. Large
reservoirs are usually constructed by Federal agencies by impounding major
rivers and are operated for multiple purposes that include water supply, flood
control, and hydroelectric power generation.
The purpose and location of an impoundment usually determines its basin
size, and the topography of the inundated valley dictates the basin shape. The
geology, soil type, and vegetation in the valley and the watershed directly affect
reservoir productivity and water quality. Because reservoirs are often flooded
river valleys, many of these man-made lakes are long and narrow rather than cir-
cular or ovoid like many natural lakes, and they tend to have irregular shorelines
(Fig. 2-2). Additionally, while natural lakes tend to have diffuse sources of inflow-
ing water, relatively low watershed areas compared to lake surface area, and
long hydraulic residence times, reservoirs usually differ in all of these traits, and
these differences account for the great differences in water quality that can
occur between lakes and reservoirs. Typically, a reservoir has one or two major
tributaries, a very large watershed compared to lake surface, and relatively short
hydraulic residence times. The contributions of dissolved and paniculate organic
and inorganic materials to the lake from the watershed are also likely to be very
high for reservoirs.
Lake Processes
Epilimnion: Uppermost,
warmest, well-mixed layer
of a lake during summer-
time thermal stratification.
The ep/limnion extends
from the surface to the ther-
mocline.
Hypolimnion: Lower,
cooler layer of a lake during
summertime thermal stratifi-
cation.
Lake Stratification and Mixing

In spring and early summer, the combination of solar heating and wind mixing of
near-surface water layers brings about the warming of the upper portion of the
lake water column and the stratification of many lakes and reservoirs into layers
of water with different temperatures and densities (Fig. 2-3). Rapidly flushed,
shallow lakes that are exposed to strong winds, however, do not normally
develop persistent thermal stratification.
During summertime thermal stratification, a warmer, less dense layer of water
(the epilimnion) floats on a cooler, denser water layer (the hypolimnion). These
two layers are separated by a zone of rapidly changing temperature and density
called the metalimnion. The term metalimnion is often used loosely. The classical
definition is the stratum of water of rapid thermal change with depth, above and
below which are zones of uniformly warm (epilimnion) and cold (hypolimnion)
water layers. The thermodine is a horizontal plane of water across the lake
through the point of the greatest temperature change. The thermocline is within
the metalimnion.
Mixing Processes
The most important lake mixing mechanisms are wind, inflowing water, and out-
flowing water. Wind affects the surface waters of all lakes, but the effectiveness
of wind in mixing the entire water column is sharply curtailed in some lakes
during the summer. During summertime thermal stratification, a lake usually can-
2-8
-------
Lake bottom
Natural Lake
— Lower watershed area: lake surface area ratio
— Longer hydraulic residence time
— Frequently deeper
— Frequently simpler in shape
VVatevshedbpunclary
Reservoir
— Higher watershed area: lake surface area ratio
— Shorter hydraulic residence time
— Frequently shallower
— Frequently more convoluted in shape

Figure 2-2.-Comparison of reservoirs to natural lakes.
not be completely mixed by wind. When its temperature-controlled zonation
breaks down in the fall, the waters cool, and mixing from the top to bottom oc-
curs.
In stratified lakes, the thickness of the epilimnion can be considered to be the
depth to which water is consistently mixed by wind. How deep (or thick) this
layer becomes during the summer depends upon how resistant the water is to
mixing. The greater the temperature difference between the epilimnion and the
hypolimnion, the more wind energy would be required to mix the water column
completely to the bottom of the lake (see Special Section: The Unique Proper-
ties of Water). The density gradient (change in density) of the metalimnion acts
as a physical barrier to complete mixing of the epilimnion and hypolimnion.
2-9
-------
EPILIMNION OR MIXED LAYER-WARM (LIGHT) WATER
THERMOCLINE (PREVENTS MIXING)
DEGREES FARENHEIT
Figure 2-3.-A cross-sectional view of a thermally stratified lake. The curved line (the water
temperature profile) illustrates how rapidly the water temperature decreases in the metal-
imnion compared to nearly uniform temperatures in the epilimnion and hypolimnion. The
metalimnetic density gradient associated with this region of rapid temperature change pro-
vides a strong, effective barrier to water column mixing during the summer months.
Decomposition: The trans-
formation of organic mole-
cules (e.g., sugar) to inor-
ganic molecules (e.g., car-
bon dioxide and water)
through biological and non-
biological processes.
In the spring, just after thermal stratification is established, the hypolimnion
will be rich in dissolved oxygen from early spring water mixing and plant oxygen
production. However, because of the barrier properties of the thermocline, the
hypolimnion is isolated from gas exchanges with the atmosphere during the
summer and is often too dark for plant production of oxygen. In a productive
lake, the hypolimnion can then become oxygen depleted over the period of sum-
mer thermal stratification as its reserve of dissolved oxygen is consumed by the
decomposition (respiration) of organic matter by microbes. This event has very
important consequences for lake productivity and fish management and is one
of the major targets of lake restoration activities.
As the epilimnion cools in the late summer and fall, the temperature difference
between layers decreases, and mixing becomes easier. With the cooling of the
surface, the mixing layer gradually extends downward until the entire water
column is again mixed and homogeneous (Fig. 2-4). This destratification
process is often referred to as fall overturn.
Water Movements

The wind-driven vertical mixing of the water column, just discussed, is only one
of several types of water movements in lakes.
The downstream flow of water usually controls the transport of dissolved and
suspended particles, particularly in river-like lakes and in many large, man-made
impoundments are dominated by major tributaries. Many natural lakes, however,
have numerous, diffuse inflows (including subsurface inflows) and a surface out-
2-10
-------
(A.) SUMMERTIME THERMAL STRATIFICATION
EPILIMNION

THERMOCLINE
METALIMNION

HYPOLIMNION
(B.) ANNUAL CYCLE OF THERMAL STRATIFICATION
Y^S*f^**7
SPRING
OVERTURN
\ EARLY /
\ FALL /
FALL
OVERTURN
Figure 2-4.-Seasonal patterns in the thermal stratification of North Temperate zone lakes
and reservoirs: (A) summertime stratification; (B) the annual cycle of lake thermal stratifica-
tion.

let. In such lakes, the downstream flow of water from the watershed is not of
major influence on lake water movements. Commonly, large reservoirs have
deep subsurface (often hypolimnetic) outlets from the dam that tend to promote
the occurrence of subsurface density flows. A density flow occurs when inflow-
ing water is cooler and thus denser than the epilimnetic water and, therefore,
sinks or plunges to a depth of equivalent water temperature or density before
continuing its downlake flow (Fig. 2-5).
Under stratified conditions, these density flows may pass through an entire
reservoir along the bottom or at an intermediate depth without contributing sig-
nificant amounts of nutrients or oxygen to the upper mixed layer. This is a com-
mon phenomenon in a series of deep-discharge impoundments. Cold water
released from an upstream reservoir may traverse the next reservoir in the series
as a discrete flow. This short-circuiting underflow may even be perceived as
desirable for water quality, because it allows nutrient-laden water to flow through
without contributing to nuisance levels of algal production. Fishermen, however,
may view the short circuit with less enthusiasm because this reduction in algal
production may be detrimental to overall lake production of fish.

Organic Matter Production and

Consumption

Photosynthesis and Respiration

Planktonic algae (phytoplankton) and macrophytes use the energy from sun-
light, carbon dioxide, and water to produce sugar, water, and molecular oxygen.
The sun's energy is stored in the sugar as chemical bond energy. The green
Density flows: A flow of
water of one density (deter-
mined by temperature or
salinity) over or under water
of another density (e.g.,
flow of cold river water un-
der warm reservoir surface
water).
Macrophytes: Rooted and
floating aquatic plants,
commonly referred to as
waterweeds. These plants
may flower and bear seed.
Some forms, such as duck-
weed and Coontail (Cerato-
phytlum) are free-floating
forms without roots in the
sediment.
2-11
-------
Tlie layer of greatest
temperature change, the
metalimnion, presents a bar-
rier to mixing. The thermocline
is not a layer, but a plane
through the point of maximum
temperature change. The
epilimnion and hyplimnion
are relatively uniform in
temperature. As the graph il-
lustrates, ice is much less
dense (lighter) than water.
Warm water is less dense than
cold water, but not as light as
ice. Density changes most
rapidly at warm temperatures.
The Unique Properties of Water

Water is a unique substance, and in order to understand how lakes be-
have, it is useful to understand water's physical and chemical properties.
The molecular structure of water and the way in which water molecules
associate with each other dictate these properties:
1. Water is an excellent solvent; many gases, minerals, and organic
compounds dissolve readily in it.
2. Water is a liquid at natural environmental temperatures and pres-
sures. Although this property seems rather common and obvious to us, in
fact, it is quite important. If water behaved at ordinary temperatures and
pressures as do chemically similar inorganic compounds, it would be
present only as a vapor and lakes would not exist.
3. The temperature-density relationship of water is also unique. Most
liquids become increasingly dense (more mass, or weight, per unit
volume) as they cool. Water also becomes rapidly more dense as its
temperature drops, but only to a certain point (Fig. 2-C). Water reaches its
maximum density at 39.2 °F (3.94 °C), then it decreases slightly in density
until it reaches 32 °F (0 °C), the freezing point. At this point, ice forms and
density decreases sharply. Ice, therefore, is much lighter than liquid water
and forms at the surface of lakes rather than at the lake bottom.
Temperature and the Density of Water
0 5 10 15 20 25 30 °C
THERMOCLINE

at 4°C Water
less dense as it
r as it cools
)-25°C = 60-75°F
5-20 °C = 45-65 °F
l-15°C - 392-45°F
°°;I ° ; EPIUMNION 20-25 °*C > { I
°°-°°. METALIMNION 15-20°cY%"
•V-; HYPO°LIM° ION 4-1 "°C\%;
1 ooooo

0 99900

0 99800

0.99700

0.99600

0 99500

092
TEMPERATURE °C

0 +5 10 15 20 25 30

LIQUID TO ICE
-"
Figure 2-C.-The temperature-density relationship of water enables deep lakes to strat-
ify during summer. (See explanation in side column.)
A second important consequence of the temperature-density relation-
ship of water is the thermal stratification of lakes. Energy is required to mix
fluids of differing densities, and the amount of energy necessary is related
to the difference in density. In the case of the water-column mixing in
lakes, this energy is provided primarily by wind. Therefore, the changes in
water density that accompany rapidly decreasing water temperatures in
the metalimnion during summer stratification are of great importance. This
metalimnetic density gradient provides a strong and effective barrier to
water-column mixing.
4. Water also has an unusually high specific heat. Specific heat is the
amount of energy required to change the temperature of 1 g of water by
1°C. Water also has a high latent heat of fusion, which is the energy re-
quired to melt 1 g of ice at 0 °C. These properties make lakes slow to thaw
and warm in the spring and slow to cool and freeze in the fall, thus provid-
ing exceptionally stable thermal environments for aquatic organisms.
Additionally, because water gains and loses heat slowly, the presence of
large lakes can exert a significant influence on local and regional climate.
A good example is the Great Lakes, which have a dramatic effect on both
the air temperature and on the precipitation in the States and Provinces
surrounding them.
2-12
-------
Figure 2-5.-Density flows in reservoirs. Often the inflowing tributary and reservoir waters
differ in temperature and, therefore, in density. If the river inflow is warmer and less dense
than the reservoir water, the "lighter" inflow will spread over the reservoir surface as an
overflow. If river inflow is cooler and denser than the entire reservoir water mass, it will
proceed along the reservoir bottom as an underflow. If river inflow is of an intermediate
density, it will "plunge" from the surface and proceed downstream at the depth at which the
river water and reservoir water densities are equal.
pigment, chlorophyll, is generally required for plants to do this. Sugar, along with
certain inorganic elements such as phosphorus, nitrogen, and sulfur, is then
converted by plant cells into organic compounds such as proteins and fats. The
rate of photosynthetic production of sugar is called primary productivity. The
amount of plant material produced and remaining in the system is called primary
production and is identical in process of origin to the standing crop or biomass
of plants in a farmer's field. While photosynthesis in the lake normally is the
dominant source of organic molecules for the food web, most lakes receive sig-
nificant additional inputs of energy in the forms of dissolved and paniculate or-
ganic matter from their watersheds.
Primary productivity: The
rate at which algae and
macrophytes fix or convert
light, water, and carbon
dioxide to sugar in plant
cells. Commonly measured
as milligrams of carbon per
square meter per hour.
2-13
-------
Phytoplankton: Micro-
scopic algae and microbes
that float freely in open wa-
ter of lakes and oceans.
In the process of photosynthesis, molecular oxygen is produced as well, and
this is the primary source of oxygen in the atmosphere and dissolved in water.
Oxygen is usually required to completely break down organic molecules to
release the light energy they contain. Plants and animals release this energy to
do work through a process called respiration. Its end-products are energy, carb-
on dioxide, and water, produced by the breakdown of organic molecules in the
presence of oxygen.
Because of its requirement for light, the primary (photosynthetic) production
of organic matter by aquatic plants is restricted to the portion of the lake water
column that is lighted (also called the photic zone). The thickness of the lighted
zone depends upon the transparency of the lake water. The photic zone is the
depth to which at least 1 percent of the surface light intensity penetrates. Below
this, in the aphotic zone, the available light is too weak to support a significant
amount of photosynthetic production.
Phytoplankton production is controlled largely by water temperature, light
availability, nutrient availability, hydraulic residence time, and plant consumption
by animals. Macrophyte production is thought to be controlled more by
temperature, light, and bottom soil types; most rooted macrophytes obtain their
nutrients from the bottom sediments rather than the water and are restricted by
light penetration to the shallow littoral water.
When light is adequate for photosynthesis, the availability of nutrients often
controls phytoplankton productivity. In the lake, differences between plant re-
quirements for an element and its availability exert the most significant limit on
lake productivity. Table 2-2 compares the relative supply of essential nutrients to
their demand for plant growth. Phosphorus and nitrogen are the least available
elements, and therefore, they are the most likely to limit lake productivity.
Table 2-2.—The listed elements are required for plant growth. Plant demand is
represented by the percentage of these essential elements in the liv-
ing tissue of freshwater plants. Supply is represented by the propor-
tions of these elements in world mean river water. The imbalance
between demand and supply is an important factor in limiting plant
growth (after Vallentyne, 1974).
ELEMENT
Oxygen
Hydrogen
Carbon
Silicon
NITROGEN
Calcium
Potassium
PHOSPHORUS
Magnesium
Sulfur
Chlorine
Sodium
Iron
SYMBOL
o
H
C
Si
N
Ca
K
P
Mg
S
Cl
Na
Fe
DEMAND BY
PLANTS (%)
80.5
9.7
6.5
1.3
.7
.4
.3
.08
.07
.06
.06
.04
.02
SUPPLY IN DEMAND: SUPPLY
WATER (%) RATIO1
89
11
.0012
.00065
.000023
.0015
.00023
.000001
.0004
.0004
.0008
.0006
.00007
1
1
5,000
2,000
30,000
< 1,000
1,300
80,000
< 1,000
< 1,000
<1,000
<1,000
< 1,000
1 Percent of element in plant tissue / percent in available water The higher the ratio, the more scarce the nutrient Phosphorus,
in particular, is likely to limit plant growth in a lake If more phosphorus is supplied, however, plant growth is likely to accelerate
unless and until limited by some other factor
2-14
Phosphorus in particular can severely limit the biological productivity of a lake
for many natural lakes. The by-products of modern society, however, are rich
sources of this element. Wastewaters, fertilizers, agricultural drainage, deter-
gents, and municipal sewage contain high concentrations of phosphorus, and if
allowed to enter the lake, they can stimulate algal productivity. Such high
-------
productivity, however, may result in nuisance algal blooms, noxious tastes and
odors, oxygen depletion in the water column, and undesirable fishkills during
winter and summer.
Since phosphorus is most often the nutrient that limits algal productivity, it is
usually the element that is the focus of many lake management or restoration
techniques. Phosphorus loading can be reduced, for example, by chemical floc-
culation in advanced wastewater treatment plants or controlled in the watershed
by using proper agricultural and land management practices, improving septic
systems, and applying fertilizer carefully (see Chapter 5). In the past 20 years,
there have been increasing efforts to minimize phosphorus inputs to lakes as a
way to curb eutrophication. Methods for precipitating or inactivating phosphorus
within the lake are discussed in Chapter 6 under Algae/Techniques With Long-
Term Effectiveness. A method for determining the amount of phosphorus com-
ing from the watershed is discussed in Chapter 3, and a formula for calculating
the amount is given in Chapter 4.

Phytoplankton Community Succession

As the growing season proceeds, a succession of algal communities typically
occurs in a lake (Fig. 2-6). Phytoplankton biomass usually tends to be high in the
spring and early summer by virtue of increasing water temperature and light
availability, relatively high nutrient availability, and low losses to zooplankton
grazing (consumption by microscopic animals). As grazing pressure increases
and nutrient availability declines from early to midsummer, algal biomass
declines. It rises again in the late summer and fall when water column mixing in-
creases the supply of nutrients and other conditions provide a favorable environ-
ment for the growth of algae. Sometimes, particularly in very productive lakes,
blue-green algae form floating scums on the surface of the lake. Algal produc-
tion and biomass are usually low in the winter because of low water tempera-
tures and low light availability.
Figure 2-6.-A typical seasonal succession of lake phytoplankton communities. Diatoms
dominate the phytoplankton in the spring and the autumn, green algae in mid summer, and
blue-green algae (cyanobacteria) in late summer.
Biomass: The weight of bi-
ological matter. Standing
crop is the amount of
biomass (e.g., fish or algae)
in a body of water at a given
time. Often measured in
terms of grams per square
meter of surface.

Zooplankton: Microscopic
animals which float freely in
lake water, graze on detritus
particles, bacteria, and al-
gae, and maybe consumed
by fish.
2-15
-------
Sedimentation and Decomposition

Sedimentation is the sinking of particles (silt, algae, animal feces, and dead or-
ganisms) through the lake water column and their deposition on the lake bottom.
Sedimentation is a very important process that affects phytoplankton biomass
levels, phytoplankton community succession, and transfers of organic matter,
nutrients, and particle-associated contaminants from the lake's upper layers to
the bottom sediments. One reason for the dominance of blue-green algae in
some lakes may be related to their ability to regulate their buoyancy and, there-
fore, to counter sedimentation. Sedimentation of paniculate organic matter from
the water column to the lake bottom provides a critical linkage between
planktonic primary production and the growth of bottom-dwelling organisms
such as aquatic insect larvae, clams, and crayfish, which eat this organic matter
and upon which larger predatory organisms fish and turtles may feed.
Settling plankton, zooplankton feces, and other organic detritus particles are
degraded in the water column and in the bottom sediments through oxygen-
consuming decomposition processes. Organic matter decomposition, a collec-
tive term for the net conversion of organic material back to inorganic
compounds (see Fig. 2-7), occurs through the respiratory activities of all or-
ganisms, including bacteria, fungi and other microbes.
CO2 + H2O + NUTRIENTS + SUNLIGHT
PHOTOSYNTHESIS

RESPIRATION &
DECOMPOSITION
(CH2O) + H2O + O2
Figure 2-7.-The equilibrium relationship between photosynthesis and respiration-decom-
position processes. The photosynthetic conversion of light energy, carbon dioxide (C02),
water (H20), and nutrients into organic matter produces oxygen (02) and results in nonequi-
librium concentrations of carbon, nitrogen, sulfur, and phosphorus in organic compounds
of high potential energy. Respiration-decomposition processes tend to restore the equilib-
rium by consuming oxygen and decomposing organic materials to inorganic compounds.
In the hypolimnion of productive lakes, the sedimentation of organic matter
from the surface waters is extensive. And because algae and other paniculate
materials are abundant, light penetration through the water column to the
hypolimnion is limited or absent and photosynthesis cannot occur. Under these
conditions, the oxygen consumed in the hypolimnion and bottom sediments
during the decomposition (respiration) of this organic matter greatly exceeds the
oxygen produced. Also, as described earlier, the hypolimnion is isolated from
2-16
-------
the atmosphere by a temperature or water density barrier to mixing known as
the metalimnion. The result, in productive thermally stratified lakes, is a depletion
and sometimes almost complete absence of dissolved oxygen in the hypolim-
nion. A similar result can occur, though more slowly, in shallow, productive lakes
with a prolonged snow and ice cover.
The chemical and physical changes associated with oxygen depletion are
marked. They include increased nutrient release from the bottom sediments,
destruction of oxygenated habitats for aquatic animals, and incomplete decom-
position of sedimented organic matter. These symptoms are often characteristic
of lake trophic status (see description of trophic status in the section on Lake
Aging and Cultural Eutrophication in this chapter):
Oligotropnic lakes: Insufficient organic matter is produced in the epilimnion
to affect hypolimnetic oxygen concentrations significantly; the hypolimnion
remains well oxygenated throughout the year.
Eutrophic lakes: Organic matter decomposition can rapidly exhaust the dis-
solved oxygen in unlighted zones, leading to anoxia in the hypolimnion. During
midsummer, a temperature-oxygen squeeze can develop in stratified lakes, and
cool water fish such as trout cannot withdraw to the oxygen-depleted lower
waters and must stay in less than ideal, warmer upper waters.
In anoxic conditions, metals such as iron, manganese, and sulfur, and the
nutrients phosphorus and ammonium (a nitrogen compound) become increas-
ingly soluble and are released from the sediments to accumulate in the hypolim-
nion. Summer partial mixing events, which can occur during the passage of
summer cold fronts with wind and cold rains, can transport some of these
released nutrients to the lake surface where they may stimulate more algae
production. At fall turnover, these metals and nutrients reenter the photic zone
and may also stimulate algal blooms. Nutrients that reenter the water column
from sediments constitute an "internal nutrient load" to the lake. Lake managers
must be aware of this internal source of nutrients in addition to the nutrients
entering from the watershed.
Food Web Structure, Energy Flow, and
Nutrient Cycling

In-lake plant production usually forms the organic matter base of the lake's
predator prey communities, called food webs. Although some waterbodies
(especially rapidly flushed reservoirs) receive important supplements of organic
matter from river and stream inflow, most lakes require a reliable level of algal
and macrophyte production to maintain food webs.
Some of the organic matter produced photosynthetically by primary
producers (macrophytes and algae) is consumed by herbivores (grazers) rang-
ing from tiny zooplankton to snails to grazing minnows. Herbivores, in turn
provide a food source for the next level, the carnivores, such as predatory fish
and turtles. These general levels, from primary producers, to herbivores, to the
larger predators, constitute the food chain (Fig. 2-8). The food chain concept ex-
plains the flow of energy (Fig. 2-9) among lake organisms. Each general level of
consumers, called a trophic level, transfers only a fraction of the energy it
receives up the chain to the next trophic level. In practice, this means that a few
sport fish depend upon a much larger supply of smaller herbivores, which
depend upon a successively much larger base of plants and algae.
Trophic state: The degree
of eutrophication of a lake.
Transparency, chlorophyll-a
levels, phosphorus concen-
trations, amount of macro-
phytes, and quantity of dis-
solved oxygen in the hy-
polimnion can be used to
assess state.
Anoxia: A condition of no
oxygen in the water. Often
occurs near the bottom of
fertile stratified lakes in the
summer and under ice in
late winter.
Nutrient Cycling: The flow
of nutrients from one com-
ponent of an ecosystem to
another, as when macro-
phytes die and re/ease nu-
trients that become avail-
able to algae (organic to in-
organic phase and return).
Producers: Green plants
that manufacture their own
food through photosynthe-
2-17
-------
PISCIVOROUS
FISH
r
EAT
1-2 FT
PLANKTIVOROUS
FISH
y
EAT
6"-1 FT
ZOOPLANKTON
r
EAT
1/10 IN
ALGAE
MICROSCOPIC
NUTRIENTS
NUTRIENTS
*v RECYCLE
F^l '^••••••V: -.•-...:----.--.:• ****.-.." -
1.:'%;j':'f':'~t^i'-:7 •'.'••.?• -1- ': '-•'
BENTHIC
ORGANISMS
Figure 2-8.-The food chain.
2-18
-------
Finally, all of these organisms produce wastes and die, which provides
nourishment to the bacteria and fungi in the form of dissolved and paniculate or-
ganic matter. Decomposition of organic matter recycles nutrients for additional
plant production (Fig. 2-9).
Plant nutrient uptake, photosynthesis of
organic matter and dissolved oxygen.
**** — THERMOCLINE
Consumption of dissolved oxygen in
respiration-decomposition processes, nutrient
regeneration by organic matter decomposition
Accumulation of nutrients and organic
sediments, release of dissolved nutrients from
sediments to water
Figure 2-9.-lnfluence of photosynthesis and respiration- decomposition processes and or-
ganic matter sedimentation on the distribution of nutrients, organic matter, and dissolved
oxygen in a stratified lake.
Lake Aging and Cultural

Eutrophication

Lakes and reservoirs are temporary features of the landscape. The Great Lakes,
for example, have had their current shapes for only about 12,000 years. Over
tens to many thousands of years, lake basins change in size and depth as a
result of climate, movements in the earth's crust, and the accumulation of sedi-
ment. Lake eutrophication is a natural process resulting from the gradual ac-
cumulation of nutrients, increased productivity, and a slow filling in of the basin
with accumulated sediments, silt, and organic matter from the watershed. The
original shape of the basin and the relative stability of watershed soils strongly
influence the lifespan of a lake.
The classical lake succession sequence (Fig. 2-10) is usually depicted as a
unidirectional progression through a series of phases or trophic states:
Oligotrophy: Nutrient-poor, biologically unproductive
Mesotrophy: Intermediate nutrient availability and biological productivity
Eutrophy: Nutrient-rich, highly productive
Hypereutrophy: Pea-soup conditions, the extreme end of the eutrophic stage
These lake trophic states correspond to gradual increases in lake productivity
from oligotrophy to eutrophy (Fig. 2-10).
2-19
-------
Lake Basin Origin and Shape

The origin of the lake basin often determines the size and shape of the
lake, which in turn influences the lake's productivity, water quality, the
habitats it offers, and its lifespan.

Glacial activity has been the most common origin of lake basins in North
America (Fig. 2-D). Glacial lakes of Canada and the upper Midwestern
United States were formed about 8,000 to 12,000 years ago. Some lake
basins resulted from large-scale glacial scouring, the wearing away of
bedrock and deepening of valleys by expansion and recession of glaciers.
Deep depressions left by receding glaciers filled with melt water to form
lakes. The finger lakes of Upper New York State were formed this way.
MORAINE / CLEAN ICE f DR|FT
IN ICE
DURING GLACIATIOIM
About 3,000 years ago the last
glaciers began to retreat from
the North American continent
Many of the small lakes in the
upper midwest and north
central states as well as
Canada were formed by huge
ice blocks buried in the loose
rock and soil and deposited by
the glaciers. When the buried
ice blocks melted they left
holes in the glacial till which
filed with water from the
melting glaciers
GLACIAL TILL
AFTER GLACIATION
Chains of lakes formed along
some streams that drained the
melting glaciers. Other lakes
were created between the
moraines and the retreating
ice mass from the melting
water

MORAINE
A Moraine is a ridge of low
rolling hills made up of
unsorted rocks and soil
deposited when the glacial ice
mass melted.
Figure 2-D.-The effects of glaciation in shaping lake basins.

Kettle, or "pothole," lakes, which formed in the depressions left by melting
ice blocks, are very common throughout the upper Midwestern United
States and large portions of Canada. These lakes and their watersheds
are popular home and cottage sites and recreational areas. The size and
shape of the kettle lake basins reflect the size of the original ice block and
how deeply it was buried in the glacial debris.

Natural lakes have also been formed by volcanism; Crater Lake, Oregon,
is an example. Large-scale movements of large segments of the earth's
crust, called tectonic activity, created Reelfoot Lake in Tennessee and
Lake Tahoe in California, among others.

Solution lakes are formed where groundwater has dissolved limestone;
Florida has a number of these lakes. Lakes may also originate from shift-
ing of river channels; oxbow lakes are stranded segments of meandering
rivers. Finally, natural lakes can also be created by the persistence of the
dam-building beaver.
2-20
-------
MES07ROPHY
HYPEHEUTROPHY
TIME

MAN INDUCED
1000'S OF YEARS
100'S OF YEARS
OLIGOTROPHY
EUTROPHY/HYPEREUTROPHY
M E/H
10'S OF YEARS
Figure 2-10.-Above: The progression of natural lake aging or eutrophication through nutri-
ent-poor (oligotrophy) to nutrient-rich (eutrophy) states. Hypereutrophy represents extreme
productivity characterized by algal blooms or dense macrophyte populations (or both) plus
a high level of sedimentation. The diagram depicts the natural process of gradual nutrient
enrichment and basin filling over a long period of time (e.g., thousands of years).
Below: Man-induced or cultural eutrophication in which lake aging is greatly accelerated
(e.g., tens of years) by increased inputs of nutrients and sediments to a lake, as a result of
watershed disturbance by man.
Evidence obtained from sediment cores (see Chapter 3), however, indicates
that changes in lake trophic status are not necessarily gradual or unidirectional.
If their watersheds remain relatively undisturbed, lakes can retain the same
trophic status for many thousands of years. Oligotrophic Lake Superior is a
good example of this. In contrast, rapid changes in lake nutrient status and
productivity are often a result of man-induced disturbances to the watershed
rather than gradual enrichment and filling of the lake basin through natural
means.
Man-induced cultural eutrophication occurs when nutrient, soil, or organic
matter loads to the lake are dramatically increased. The lifespan of a lake can be
shortened drastically by activities such as forest clearing, road building, cultiva-
tion, residential development, and wastewater treatment discharges because
these activities increase soil and nutrient loads to the lake. Chapter 5 explains
watershed influences from these activities in the sections on nonpoint and cul-
tural sources.
Some lakes, however, are naturally eutrophic. It is important to recognize that
many lakes and reservoirs located in naturally fertile watersheds have little
chance of being anything other than eutrophic. Unless some other factor such
as turbidity or hydraulic residence time intervenes, these lakes will naturally have
very high rates of primary production.
Natural and man-made lakes undergo eutrophication by the same proces-
ses—nutrient enrichment and basin filling-but at very different rates (Fig. 2-10).
Reservoirs become eutrophic more rapidly than natural lakes, as a rule, because
most reservoirs receive higher sediment and nutrient loads than do most natural
lakes. They may even be eutrophic when initially filled. Reservoirs, especially
those with hypolimnetic outlets, are considerably more efficient at trapping sedi-
ments than at retaining nutrients, and therefore, the filling of their basins with
river-borne silts and clays is the dominant aging process for reservoirs.
2-21
-------
Ecology's Place in Protection
and Restoration
The goal of this chapter on ecological and limnological concepts is to provide
the reader with a basic background for understanding the origins of lake
eutrophication and water quality problems. This background is intended to help
the reader evaluate the potential benefits and limitations on lake protection and
restoration approaches and techniques described in the rest of this Manual.
This Manual emphasizes two basic, complementary approaches to lake res-
toration:
1. Treating the causes of eutrophication. This approach involves limiting lake
fertility by controlling nutrient availability.
2. Treating the products of overfertilization and thus controlling plant produc-
tion in the lake.
Methods employed to control nutrient availability include proper watershed
management practices, advanced treatment of wastewater, and diversion of
wastewater and stormwater (see Chapter 5). Hypolimnetic withdrawal, dilution
and flushing, phosphorus precipitation and inactivation, sediment oxidation,
sediment removal, and hypolimnetic aeration are techniques to deal with
nutrients already in the lake system; they are discussed in Chapter 6.
Methods used to control plant biomass include artificial circulation, water-
level drawdown, harvesting, chemical treatments (herbicides and algicides),
biological controls, and shading and sediment covers for macrophyte control.
Chapter 6 provides details on these techniques also.
Determining what needs to be treated and where problems may originate is
discussed in Chapter 3 on Problem Identification. Chapter 5 gives further infor-
mation on watershed influences and how to manage them.
Most of what we know about lake and reservoir restoration has been learned
in the last 15 years through experience gained from many studies conducted in
the United States, Canada, Europe, and Scandinavia. Experience gained from
previous lake restoration efforts clearly leads to three conclusions:
1. There is no panacea for lake management or restoration problems; dif-
ferent situations require different approaches and solutions.
2. A complex set of physical, chemical, and biological factors influences lake
and reservoir ecosystems and affects their responsiveness to lake restoration ef-
forts.
3. Because of the tight coupling between lakes and their watersheds, good
conservation practices in the watershed are essential for improving and protect-
ing lake water quality. Efforts to control both external loading of nutrients from
the watershed and internal nutrient loading and recycling are often required to
produce a noticeable improvement in water quality.
2-22
-------
Summary

The character of a lake or reservoir is determined by a complex set of
physical, chemical, and biological factors that vary with lake origin and
current conditions. Important factors include hydrology, climate, water-
shed geology, watershed to lake ratio, soil fertility, hydraulic residence
time, lake basin shape, external and internal nutrient loading rates,
presence or absence of thermal stratification, lake habitats, and lake
biota. In some situations, a natural combination of these factors may dic-
tate that a lake will be highly productive (eutrophic) and management or
restoration efforts to transform such a system to an unproductive, clear-
water (oligotrophic) state would be ill-advised. However, if a lake has be-
come eutrophic or has developed other water quality problems as a result
of, for example, increased nutrient loading to the lake from the watershed,
then these effects can be reversed and the condition of the lake can be
improved or restored by an appropriate combination of management ef-
forts in the watershed and in the lake itself. The best situation is one where
steps are taken to protect the lake's watershed before problems develop.

In the chapters to follow, a variety of lake and watershed management
techniques are discussed and compared. While reading through this in-
formation it is important to remember that the potential effectiveness of
any lake restoration method or combination of methods will depend en-
tirely on the ecological soundness of its application. Recent experience in
lake restoration has clearly shown that there is no panacea for lake res-
toration or for lake management problems. That is (despite the
salesman's claims), introducing grass carp, harvesting weeds, or install-
ing an artificial aeration/destratification system is not necessarily the solu-
tion for a particular lake. In fact, all three of these commonly used
methods address symptoms rather than causes.

Finally, lakes and their watersheds are tightly coupled. Therefore, to be ef-
fective, lake and reservoir restoration and management efforts must con-
sider both watershed processes and lake dynamics.
2-23
-------
CHAPTER 3
Problem Identification
-------
CHAPTER 3
PROBLEM IDENTIFICATION
Chapter Objectives

In the first chapter of this Manual, a lake problem was defined as a limitation on a
desired use of the lake. Based on this definition, problems can often be identified
by simply listing lake users' complaints. When boat owners can't put their boats
in the water or get away from the dock because of weeds, for example, they
have clearly identified a problem. While this identification of a problem is usually
the first action in the process of reaching a solution, a number of other steps
must occur between pointing to an apparent problem and implementing a plan
that truly solves it. These steps are illustrated in Figure 3-1.
The purpose of this chapter is to help lake users, managers, and associations
• Identify problems
• Put problems in perspective for a particular lake
• Understand how the causes, not the symptoms of problems are
determined through diagnostic analysis of the lake
• Define the causes of the lake problems
Finally, this chapter directs the reader to appropriate parts of this Manual to
evaluate the alternatives for solving these problems.
Common Lake Problems
Most types of lake problems commonly occur in a number of lakes in a region.
Rarely is a problem unique to a particular lake. Some of these widely occurring
lake problems, impaired uses, and possible causes are listed in Table 3-1.
Among these common lake problems, overabundant algae, excessive macro-
phytes, lack of depth and user conflicts frequently arouse public complaints and
provide good examples of the relationship between lake users and lake condi-
tions.
3-1
-------
Problem Identification
Common lake problems
(See Chapter 2 for reasons)
Algal scums - Poor fishing
Weeds - Odor
Color and muddy waters
Overcrowding/user conflicts
Problem statement
(symptoms)
Lake users
Lake association
Community
Problem identification
Possible
causes
Perception
Private
Sector

Universities
Consultants
Contractors
Organization
Problem diagnosis
Available data
Data collection
Modeling techniques
Indices
(See Chapter
Problem definition
Possible solutions
Watershed
Management
(See Chapter 5)
V
In-lake
Restoration
(See Chapter 6)
Lake management plan
(See Chapters 7, 8, 9)
Public
Sector

Local
Federal
State
Figure 3-1.-General approaches can be described for defining lake problems in terms of
users' needs and investigating causes to reach a solution that fits both the lake's capabili-
3-2 ties and the needs of users.
-------
Table 3-1.—Examples of common lake problems, impaired uses, and possible causes of the problem.
Impared Uses
Aesthetics
Fishing

ALGAE SCUM WEEDS
'High Nutrients 'Shallowness
'High Nutrients
'Sediment
*
COMMON PROBLEMS/SYMPTOMS
FISH KILLS DEPTH
*
'Toxins _
'No Oxygen ]^

USER CONFLICTS
'Motor Boat Noise
'Debris
'Motor Boating
'Swimming

TASTE & ODOR
"High Nutrients
'HighOrganics
'Algae
l^l^
'HighOrganics
'Sediment
Swimming

Motorboating

Sailing

Water Supply
_
'Motor Boating
'Swimming
'Scuba Diving

'Motor Boating
'Swimming
'Scuba Diving

'Swimming
(contamination)
'Motor Oils, Gas
'Debris
<^i^ = problem shown above definitely impairs use shown at left
n* = problem shown above may impair use shown at left
" = common causes of problem shown above; definite impairment of use
U
w
-------
Algae: Small aquatic plants
which occur as single cells,
colonies, or filaments.
Algae
Algae are a vital part of all lakes (see Chapter 2); they are one of the sources of
food and energy for fish and other lake organisms. Too many algae and the
wrong kinds of algae, however, can interfere with some lake uses. For instance,
they can clog the filters of drinking water treatment plants. Also, organic matter
produced by algae can react with chlorine. Trihalomethanes- possible products
of this chemical reaction-are believed to cause cancer. Algae can also inhibit
the growth of other plants by shading them, contribute to oxygen depletion and
fishkills, and cause taste and odor problems in water and fish. Some species of
algae can release toxins.
The most common use of lakes is aesthetic enjoyment; excess algae are
most likely to interfere with the simple pleasure of viewing a lake from a resort, a
cottage, a home, a park, or a highway. Unsightly scums are especially likely to
be caused either by tangled masses of filamentous algae or by "blooms" of cer-
tain planktonic algae that float on the lake surface.
The regular occurrence of algal blooms indicates that nutrient levels in the
lake are too high.
Weeds

Weeds also limit many lake uses. Like algae, weeds (or aquatic macrophytes)
are a vital part of the lake (see Chapter 2). They provide cover for fish and food
for wildlife. But too many weeds can limit swimming, fishing, skiing, sailing, boat-
ing, and aesthetic appreciation. Indeed, getting rid of noxious weeds is one of
the most common drives among lake associations. Fifty percent of Wisconsin
lake districts report harvesting weeds, and 25 percent use herbicides (Klessig et
al. 1984).
Depth
Depth problems result from the loss of volume in a lake or reservoir because of
increased sediment load. Increased sediment generally leads to problems with
turbid or murky water. The reduction in depth can disrupt swimming, boating,
and sailing activities and encourage extensive weed growth. Increased sediment
loads originate externally as soil erosion in the watershed or internally from
decaying algae and weeds in the lake itself. The loss of lake volume, or infilling, is
a problem in a majority of lakes and reservoirs. Dredging has been one of the
major lake restoration approaches used in lake management. Dredging,
however, doesn't stop the soil erosion in the watershed.

User Conflicts

Not all lake problems occur because of physical, chemical, and biological condi-
tions in the lake. User conflicts arise from limitations on the time and space avail-
able for desirable activities. Some lake uses clearly conflict with others.
Motorboating can disrupt fishing, swimming, and scuba diving in a lake. Just the
sound of boat motors can disturb the aesthetic pleasures derived from a lake
setting. Mudflats created by lake drawdown for power generation or water supp-
ly conflict with the desire to have a constant water level for aesthetics, docking
boats, and wading. Conflicts among desired lake uses can cause greater lake
problems than those arising from algal scums or an overabundance of weeds.
3-4
-------
Problem Statement
A local homeowner or lake user will probably be aware of lake problems before
a professional lake manager suggests that something is wrong. User percep-
tions are often the first qualitative indicators that the lake has or does not have a
problem. If a boater cannot move across the shallow areas of a lake because of
dense macrophytes or if a swimmer cannot enjoy a dip without entanglement
with macrophytes, a problem exists. If a homeowner relaxing in the confines of
the yard is offended by the smell of decaying macrophytes and algae, a problem
exists. For these lake users, the most productive response to such problems can
be to form an organized group to deal with the problems and to determine the
interest in seeking a solution to the problems. Local initiative is an important part
of lake restoration; it helps local users understand how the lake works (and their
role in the problems) and enables them to cooperate in the solution. Determin-
ing why problems exist and how serious they are relative to the natural carrying
capacity of the lake, however, typically requires professional assistance.
Lake organizations invariably would like to see their lake do everything. They
want aesthetic pleasure, great fishing, healthy water, sandy shorelines and bot-
toms, and a nice wildlife population all without pests, insects, or weeds. Unfor-
tunately, almost no lake can meet all of these demands. Systematically clarifying
the attainable uses in a lake management effort must be the first step of any
plan.
Local users, homeowners, or lake associations have two responsibilities in
lake restoration that require considerable attention. The first one is to come to
some agreement on what the problems are, clearly stating these problems and
determining how to organize to see that the problems are resolved. Appen-
dix 3-A describes two democratic procedures, the nominal group process and
the Delphi process, that may prove useful for the first responsibility. The second
responsibility is to assure that analysis of the causes of problems and a viable
response to these factors is carried out by competent professionals.
Based on both what the users want and what the lake itself is capable of sup-
porting, problem identification focuses first on establishing a set of realistic uses
desired in the lake.
Problem Identification

Problem Perception
Depending on physical characteristics of the lake basin, the watershed and the
quality of incoming water, lakes are suited to particular purposes. Table 3-2 sum-
marizes general lake types that are suited to specific uses.
Although it may be technically possible to drastically alter a lake to meet the
needs of a certain user group, the cost will be high and the decision is usually
unwise. It is important to understand the lake uses that can realistically be at-
tained when choosing a desired use. Some lakes can never be crystal clear, no
matter what measures are taken. If the watershed area is large relative to lake
surface area and watershed soils are highly erodible and nutrient-rich, the lake
will always have excessive algae and weed growth regardless of any lake treat-
ments.
3-5
-------
Oligotrophic: "Poorly nour-
ished," from the Greek. De-
scribes a lake of low plant
productivity and high trans-
parency.
Table 3-2.—Priorities for lake use based on lake characteristics
SIZE OF LAKE
DEPTH
CLARITY
USES
SMALL LARGE SHALLOW DEEP TURBID CLEAR
(LESSTHAN (OVER500 (LESSTHAN5' (OVER20') (SECCHI (OVERS')
10 ACRES) ACRES AVG. DEPTH) UNDER 2')
Water
Supply

Fishing/
Wildlife

Swimming/
Skiing

Boating/
Sailing

Aesthetics
- = not suitable
- - suitable
+ - = suitability depends on modifying factors
Regional differences in lakes across the country represent an important factor
in understanding the limitations of lake management. These differences are dis-
tinct enough to be identified as regions, called ecoregions (Omernik, 1987).
Regional differences in geology, soils, land use, and vegetation in these
ecoregions result in very different lake quality. Lakes in northern Minnesota, for
example, have lower nutrient and algal concentrations and greater transparency
than lakes in southern Minnesota in areas with more naturally fertile soils. Man-
made reservoirs generally are more turbid than natural lakes. Lake users from
different regions of the country, therefore, may perceive a problem in local lakes
that is due to natural causes. One of the important parts of problem definition is
to delineate natural from man-made causes of a problem.
Sometimes, users perceive a lake problem for which a source or cause might
not exist. Perceived problems are no less important than real problems with un-
derlying causes and need to be addressed. For example, people who won't
swim in a lake because a sewage treatment plant discharged into one of the
lake's tributaries 15 years ago are still reacting to historic conditions. People per-
ceive a continuing problem, even though the problem was solved more than a
decade ago. Although it is important to distinguish between real and perceived
problems, it is equally important to identify and solve the causes of both types of
problems.

Causes of Lake Problems

The fact that most problems commonly occur in a number of lakes in the region
means that the general causes of these problems and a variety of approaches
for solving them also are known. While the solution for each common problem
must be lake-specific because each lake has unique characteristics, general ap-
proaches can be described for defining lake problems and causes (see Fig. 3-1).
Identifying the potential causes of lake problems requires an understanding
and appreciation of the interactions not only among components within the lake
such as algae, macrophytes, fish, and other organisms but also the interactions
between the lake and its watershed (see Chapters 2 and 5). In some situations, a
natural combination of these factors may dictate that a lake will be highly biologi-
cally productive and that management and restoration efforts to transform such
a system to an oligotrophic state would be ill-advised.
3-6
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If, however, a lake has become eutrophic or has developed other water
quality problems as a result of manageable problems such as an increased
nutrient load from man-made causes, then these effects can be reversed, and
the condition of the lake can be improved or restored by an appropriate com-
bination of management efforts in both the watershed and the lake itself.
Delineating natural causes versus man-made causes of problems can be en-
hanced by looking at other lakes in the same region. If there are lakes in the area
that have similar water quality but relatively undisturbed watersheds, then the
problems occurring in the lake might be due to natural causes. If these other
lakes in the region with relatively undisturbed watersheds, however, have the
quality of water that is desired, then man-made causes are probably contributing
to lake problems, and these causes need to be identified. Using other lakes in
the region with relatively undisturbed watersheds for reference is a good way to
initially assess the potential impacts of man-made or cultural sources to the lake
problems.
There are numerous tools available for identifying the causes of lake
problems. Qualitative approaches, such as comparing the target lake to sur-
rounding lakes, document subjective observations which can reveal important
patterns. The quantitative approaches, such as the models discussed in Chapter
4 and trophic state indices, rely on objective data. In practice, both qualitative
and quantitative approaches are usually considered. Using these methods to
identify underlying causes of problems usually requires professional assistance.
An important step in problem definition, therefore, is selecting a competent
professional or firm to interpret the results of various diagnostic approaches.
Selecting a Consultant
There are a number of criteria to consider in selecting a consultant. Trjese
criteria include experience in conducting lake studies, identifying the underlying
causes, and formulating effective lake management plans; expertise in engineer-
ing, limnology, biology, or other disciplines associated with lake management;
past performance in conducting similar studies or dealing with similar problems;
and the capabilities of the firm in addressing the problems in the lake. A series of
questions related to these criteria are listed in Table 3-3 and can be used to help
select a consultant or contractor. These questions need to be tailored to the par-
ticular set of lake problems and should not be considered all-inclusive. The
questions, however, should assist the lake manager and lake associations in
thinking about the appropriate questions to ask in seeking professional assis-
tance.
Limnology: Scientific study
of fresh water, especially
the history, geology, biot-
ogy, physics, and chemistry
of lakes. Also termed fresh-
water ecology.
Problem Diagnosis

Investigate the Problem
After the lake association or lake manager has selected professional assistance
and the water quality problems have been identified, the next step is to diagnose
and quantify the problems and determine their causes. This diagnosis should be
guided by the professional consultant. However, it is important for the lake
manager and/or lake association to understand the general process or steps in
problem diagnosis. Effective lake management and lake protection occurs
3-7
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Table 3-3.—Criteria for selecting consultants and contractors

A. Experience
1. How many lake restoration projects have they performed and for whom (reference
and dates)?
2. Have they successfully submitted Phase I and Phase II applications and obtained
EPA and/or State funding?
3. Have they performed Phase I Diagnostic/Feasibility Studies?
4. Have they managed Phase II Implementation Projects?
5. Have they worked on integrated watershed lake management projects?
6. Have they ever developed ordinances, zoning recommendations, or other institu-
tional approaches for protecting lakes?
7. Do they have experience with both structural and nonstructural management
techniques and procedures?
8. Have they prepared environmental assessments or impact statements?

B. Expertise
1. Do they have interdisciplinary capabilities (i.e., engineers, limnologists, chemists,
biologists)?
2. Are they familiar with the EPA and State regulations for Clean Lakes studies'?
3. What is the educational background of the project team?

C. Past Performance
1. Have they worked as a prime contractor before or primarily as a subcontractor?
2. Have they ever had cost overruns? If so, how much and why?
3. Have previous projects been completed on time?

D. Company Capabilities
1. Do they do everything in-house or do they use subcontractors?
2. Do they perform the chemical analyses themselves or in a contract laboratory?
3. Do they have the capability to collect and evaluate water quality and biological data?
4. Do they have a quality assurance/quality control (QA/QC) program?
5. Do they have experience in the following areas?
a. Analyzing physical, chemical, and biological factors
b. Performing nonpoint source studies, including setting up automated monitoring
stations and stream gaging stations
c. Analyzing the trophic condition of the lake
d. Analyzing wet and dry weather data to calculate a reliable annual nutrient and
sediment loading budget
e. Evaluating best management practices and in-lake restoration techniques
f. Analyzing institutional approaches for implementation of proposed management
and in-lake restoration activities
g. Assisting in public participation activities
h. Understanding and working with the EPA Clean Lakes Program
through an understanding and identification of the underlying causes of
problems.
Problem diagnosis is a process that provides greater quantitative resolution
on the sources or causes of the lake problems with each step. Once the causes
of the lake problems are clearly defined, then several alternative watershed
management practices (Chapter 5) and lake restoration techniques (Chapter 6)
can be evaluated to reduce or solve these problems.
At this stage, the lake problems have been identified by the lake users, and
potential causes generally are known. Algal scums, for example, result from
excess nutrients, typically phosphorus, in the lake. Weeds grow in areas that are
shallow and may be filling in with nutrient-rich sediments. Taste and odor
problems can result from algal scums or the decay of organic matter in the lake.
Problem diagnosis identifies which of the potential causes are contributing to the
problems and determines their relative importance.
Diagnosis is generally a two-step process: collating and evaluating existing
data; and collecting and analyzing additional data. The first step, using existing
data, might be sufficient in some instances to provide sufficient problem resolu-
3-8
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tion for alternative control strategies to be evaluated. Generally, additional data
are required, but this first step, at a minimum, identifies major data gaps and
provides for the design and implementation of a more cost-effective and efficient
data collection program.
Preliminary Analyses
Preliminary analyses include obtaining any existing information available on
both the watershed and the lake and making a few basic back-of-the-envelope
or desk-top calculations. Typically, a considerable amount of information will be
available on the watershed and lake. Watershed districts, sanitary districts,
county extension offices, county soil and water conservation districts, and city,
county and regional planning agencies usually have maps, land use data, or
aerial photographs on the watershed and lake. Water quality data might be avail-
able on the inflowing streams or the lake itself. Fishing maps might be available
for the lake that show the surface area, depth contours, location of inflowing
streams, coves and embayments and other features of the lake that can be im-
portant in diagnosis. Recent aerial photographs taken during mid- to late sum-
mer can show the extent of weed beds in the lake.
Watershed land use and topographic maps can be used to determine the
location and acreage of various types of crops in the watershed, the soil types in
the watershed including their potential for erosion, the location of feedlots and
barnyards, residential or housing developments, forested and open land, and
any conservancy districts. The location of wastewater treatment, industrial dis-
charges, and storm sewers can be obtained from the sanitary district, city health
department, or State natural resource or pollution control agency. In addition,
discharge data, organic matter (for example, BOD), and nutrient concentrations
in the wastewater discharge usually can be obtained from the wastewater treat-
ment plants Discharge Monitoring Records (DMR's) required by the U.S.
Environmental Protection Agency.
Estimates of annual runoff of water from the watershed or the amount of
stream inflow to the lake might be available from the city or county planning
agencies, U.S. Geological Survey, or Soil Conservation Service. The location of
groundwater wells in the watershed also might be available from these agencies,
the health department or pollution control agencies. Groundwater wells can indi-
cate the direction of flow and loading to seepage lakes (Fig. 3-2).
Existing monitoring data for temperature, dissolved oxygen, nutrients, and
algae (chlorophyll) in the inflowing stream or lake are invaluable in this phase of
problem diagnosis. Unfortunately, in many instances monitoring data are not
available for even Secchi depth determinations, which are quick and easy to do.
If monitoring data are available, the progressive deterioration of lake water
quality or onset of a lake problem might be traced back to some change in
watershed land use or lake usage that has occurred.
Existing data should be evaluated for clues on why problems are occurring in
the lake. This diagnosis is enhanced by performing some basic back-of-the-en-
velope analyses. The analyses involve the construction of a simple lake budget
that accounts for the input and output of organic matter, sediment, and nutrients
to and from the lake. The budget is used similar to a household budget. In a
household budget, it is important to balance income versus savings and expen-
ses. The lake budget, for example, attempts to account for the sources and total
load of phosphorus entering the lake (income), the amount retained in the lake
that might stimulate algae or macrophyte growth (savings), and the amount
leaving the lake (expenses). The total phosphorus load, as described in greater
detail in Chapter 4, is an important diagnostic tool in determining the potential
cause of several lake problems.
Ground water: Waterfound
beneath the soil surface
and saturating the stratum
at which it is located; often
connected to lakes.

Secchi depth: A measure
of transparency of water ob-
tained by lowering a black
and white, or all white, disk
(Secchi disk, 20 cm in diam-
eter) into water until it is no
longer visible. Measured in
units of meters or feet.
3-9
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Water
Table
Septic
System
Ground-Water Observation
Wells
38-mm PVC pipe or | | 5~
32-mm galvanized pipe \T~T I

Disturbed aquifer -^_^
x1

Well screen —
Well point -~_____^^

=
u
0 1 to 1 3 m
^
&
24
\

to 31 7 m

046 to
091 m
Figure 3-2.-Groundwater observation wells.
The potential sources of nutrients, sediments, and organic matter from
agricultural land uses, wastewater treatment plants, urban areas, and forests can
be identified. These types of land uses and levels of wastewater treatment have
been investigated and some general nutrient and sediment export coefficients
associated with various land uses have been published. These land use coeffi-
cients can be used with the annual runoff coefficients and wastewater discharge
estimates to estimate the total load of material to the lake. The relative contribu-
tion of the various land use activities or wastewater treatment plants to the total
lake load also can be determined. A rough estimate of the amount of material
retained in the lake versus flowing out of the lake can be estimated based on the
hydraulic residence time (see Chapters 2 and 4). Quantities of materials such as
phosphorus or BOD associated with various levels of severity of problems in
other similar lakes can be compared with the quantity estimated for the lake
under study.
The preliminary lake budget can indicate those land use activities, including
wastewater treatment, that appear to be contributing the greatest proportions of
organic matter, sediment and nutrients to the lake and, therefore, warrant con-
sideration for watershed management practices (see Chapter 5). The budget
also might indicate that loading from the watershed doesn't appear sufficient
to produce the magnitude or severity of the problems experienced in the lake.
3-10
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Perhaps other factors such as internal processing of material in the lake or an
unmeasured and unestimated component of the budget such as septic tank
drainage or groundwater is contributing material to the lake problems. The
budget approach provides limited information on internal lake processes al-
though it does provide insight into which processes might be important based
on external loads. High sediment loads indicate potential problems with lake fill-
ing while high nutrient loads indicate algae or weed production is a potential
problem.
To refine the diagnosis and better define the cause of the problem now re-
quires the collection and analysis of additional data. This data collection effort,
however, should be guided by the results of the preliminary analysis. If agricul-
tural runoff appears to be a major contributor to the nutrient and sediment load,
for example, then data collection efforts should focus on better estimates of
loading from the various agricultural locations in the watershed to determine
which locations are contributing the greatest portion of the load to the
lake. Wastewater discharges to a lake are usually an important source of
nutrients and organic matter. The relative contribution of wastewater treatment
plant effluent, storm water sewers or septic tank seepage to the lake can be
determined by collecting samples to characterize these inputs.

Data Collection and Analysis

With the preliminary analysis as a guide, a data collection program can be
designed for problem definition. A typical data set for problem diagnosis will in-
clude measurements on
1. Water budget: surface and groundwater inputs and changes in lake level
2. Physical parameters: sedimentation rate, temperature, and transparency
3. Chemical parameters: dissolved oxygen and plant nutrients
4. Biological parameters: algae, macrophytes, fish survey
5. Other parameters as required, such as alkalinity, pH, and conductivity
6. Use of trophic state indices
Water Budget

Surface Water and Lake Level
Determining water flow into and out of the lake, as well as recording changes in
lake level, are essential for determining the annual nutrient, organic matter, and
sediment loads to the lake and establishing the carrying capacity of the lake, the
amount a lake or reservoir can assimilate each year without exhibiting problems.
The first step is to establish a lake-level gaging station. This usually consists
of placing a staff gage in the lake and making regular readings. Readings
are most accurate when the water is calm. An alternative method is placing a
stilling well that dampers out the effect of waves and continually records water
level (Fig. 3-3).
Stream gaging stations are required on major tributaries as close to where
they enter the lake as possible and at the outlet of the lake. Gaging all of the
tributaries to a lake, however, is not usually required. The water yields from
monitored subbasins within the watershed can be substituted for similar un-
monitored basins. If obvious sources of pollution are recognized near a tributary
3-11
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Typical 1960 cost $5000 per installation.
From U.S. Geological Survey

Figure 3-3.-Conventional stilling well installation for water stage recorder.

stream, then it is prudent to place another gaging station in the vicinity of the pol-
lution site.
Groundwater Measurements

The importance of groundwater nutrient contributions to a lake depends on the
size of the surface watershed contributing to the lake. For example, if the surface
watershed of a 1,000-acre lake is 50,000 acres, the water and nutrient incomes
for that lake are probably dominated by surface inputs, and the groundwater
contribution might be of little consequence. However, if the watershed area
around a 100-acre lake is only 300 acres, then the groundwater contribution
might become more important.
When managing groundwater-dominated seepage lakes such as those found
in Florida, Minnesota, Michigan, the New England States, New York, and Wis-
consin, the groundwater component of a nutrient budget becomes essential.
Defining the groundwater contribution to a lake is not as precise as for surface
waters. The same general principal, however, holds true: Water flows downhill.
The actual definition of the groundwater component is determined by measuring
the elevation of the groundwater table relative to the elevation of the lake sur-
face. Where the groundwater table is higher than the lake, the water is moving
toward the lake. If the groundwater table is lower than the lake, then the lake
water is moving out of the lake into the groundwater.
To define the groundwater basin about a lake, wells must be placed about the
surrounding land, and the water level in each well must be measured in relation
to the lake level (Figure 3-4).
3-12
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3a,b
'3c
o2b
Alga Lake
Figure 3-4.-Groundwater observation well locations on Greater Bass Lake are indi-
cated by a number followed by a letter, a, b or c. In this case, the groundwater table was
always lower than the lake level and any influence of the groundwater system, including
on-site waste disposal systems, upon the lake chemistry would be considered insignifi-
3-13
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The knowledge of the groundwater flow direction can assist in making
decisions about sewering a lake. For example, if the groundwater flow is away
from the lake on the east shore and toward the lake on the west shore, then
serious considerations should be given as to sewering the east shore for the pur-
pose of reducing nutrients entering the lake via onsite waste disposal systems.
Water Quality Monitoring

Sampling Sites

Sampling locations and depths influence the conclusions drawn from the data
collected in the lake so it is important that these stations accurately represent
conditions in the lake.
The sampling locations and depths for physical, chemical, and biological
analyses are associated directly with the properties of the lake. In lakes that are
almost round, a single station located over the deepest point may be adequate.
In lakes with branched, finger-like shorelines, multiple embayments or long nar-
row lakes and reservoirs where significant gradients in water quality might exist,
more stations will be needed (Fig. 3-5).
Long, large lakes
Inlet
Outlet
Lakes with distinct lobes or isolated bays

Inlet
Outlet
Figure 3-5.-Typical sampling locations for lakes with simple and complex shapes.

3-14
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In shallow lakes that mix continuously throughout the summer, fewer stations
will be needed, and samples taken at the surface, middepth and bottom would
be adequate. An integrated sample from the surface to just above the sediment
might be better.
In deep, stratified lakes, samples should be collected at least near the sur-
face, in the metalimnion (see Chapter 2), near the middle of the hypolimnion
(see Chapter 2) and near the bottom. One location should be at the deepest part
of the lake with other stations located in the shallower areas and prominent
bays. For reservoirs, stations should be located at the river inflow, below the
plunge point, perhaps near mid-reservoir, and at the deepest point near the
dam.
Physical Parameters

Sedimentation Rate Estimates
There are two generally accepted methods for the determination of recent
sedimentation rates in lakes and reservoirs. One method involves the determina-
tion of the radioisotopes Cesium-137 or Lead-210 in the sediments. Although
this method provides accurate estimates of sedimentation rates, it is relatively
expensive.
The second method, which is far less sensitive but also much less expensive,
is to compare the current bottom contours (the depth to the bottom) with a
similar map made several years before. The water level for these two surveys
must be the same or the depth to the bottom must be corrected if not at the
same water level. For lakes and reservoirs receiving large sediment loads, this
method is satisfactory.
The usefulness of these methods depends on the objective of the study. One
use of sediment dating is in proposed dredging projects. Before any major
dredging is undertaken, the rate of sedimentation should be determined. It is of
little value to dredge a reservoir that is filling in at a rate of 2 inches or more a
year if watershed controls for erosion are nof implemented. In general, lakes fill
in at a slower rate than reservoirs with rates for lakes ranging from 0.10-0.50 inch
per year.
Temperature
Temperature patterns or thermal stratification (see Chapter 2) influence the fun-
damental processes occurring in a lake such as dissolved oxygen depletion,
nutrient release, and algal growth. Temperature measurements are useful, for
example, in deciding whether a shallow lake mixes periodically throughout the
summer. If a shallow lake is suspected of thermally stratifying for brief periods
and then mixing, frequent (i.e., weekly) measurements should be taken during
the summer. Deeper lakes that remain stratified throughout the summer months
may not require a high frequency of sampling for temperature to understand the
general temperature patterns occurring in the lake.
An example of thermal stratification and mixing periods is shown in Figure 3-6
for Pickerel Lake over a 2-year period. This figure represents the type of informa-
tion a professional consultant will collect and analyze as part of a lake restora-
tion program. The algal problems associated with this shallow lake (40 acres,
17-foot maximum depth) are directly related to the timing of the summer mixing
3-15
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Mix
2
4
4± 6
£ 8
g- 10
Q 12
14
16
1971
N D
1972
J|F|M|A|M|J|J|A|S I 0 i N I D
1973
J|F|M|A|M|J|J|A|S|0|N
2
4
*i 6

K 8
g- 10
Q 12
14
16
Figure 3-6.-Thermal stratification and mixing in Pickerel Lake. Lines represent the depth to
which the temperature (indicated in the circle) prevails. Temperatures are in °F.

period. When the lake mixed in mid-September, clumps of blue-green algae that
were on the lake bottom were suspended into the entire lake. Cold weather
prevented any prolonged algal bloom. However, the following year Pickerel Lake
mixed in early August, again distributing blue-green algae off the bottom
throughout the entire lake. During August and September, a massive blue green
algal bloom occurred as the warm weather created favorable environmental
conditions for algal growth.
Transparency
Secchi depth is probably the most frequently used parameter in limnology. The
Secchi disk is a 20 cm plastic or metal disk that is either entirely painted white or
divided into alternating painted black and white quadrants. The disk is lowered
into the water, and the observer measures the depth at which it can no longer be
seen. This depth is recorded and is referred to as the Secchi transparency, or
Secchi depth, of the lake (see Fig. 3-7).
The assumption is that the greater the Secchi depth, the better the water
quality of the lake. The transparency is based on the transmission of light
through water and is related, in part, to the natural light attenuation of the water
being measured, the amount of inorganic suspended solids, and the amount of
organic suspended solids (algae cells). The relationship between the Secchi
transparency and the amount of algal biomass as expressed in chlorophyll-a has
been developed for a large number of lakes. Each ecoregion of the country
should develop this relationship independent of the others because turbid
waters might be normal in some regions but unusual in others. For Northern
3-16
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Secchi depth is midway-
r
Disk raised slowly to point
where it reappears
.Disk lowered slowly until it
disappears from view
Figure 3-7.-The Secchi disk is a simple and extremely useful tool for tracking long-term
trends in lake water quality.

lakes, a Secchi depth of greater than 30 feet is considered oligotrophic while the
eutrophic lakes may only have a reading of 3 to 4 feet or less during summer
algal blooms.
Chemical Parameters

Dissolved Oxygen

These determinations are extremely useful because dissolved oxygen can act as
an integrator of the health of the lake.
In shallow lakes that mix periodically during the summer, dissolved oxygen
measurements should be made at the same time temperature determinations
are being made. Periods of no mixing when dissolved oxygen in the bottom
goes to zero followed by periods of mixing can result in the release of phos-
phorus from the bottom during anoxia and eventual redistribution throughout
the lake. This can promote the development of algal blooms.
The deeper lakes that remain stratified during the summer months may not
require a high frequency of sampling for dissolved oxygen and temperature in
order to understand their water quality patterns. There is, however, a critical
period during the spring just as a eutrophic lake is beginning to stratify. At this
point, weekly measurement of dissolved oxygen at 1- or 2-ft intervals is sug-
gested until the dissolved oxygen concentration approaches zero in the
3-17
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hypolimnion. The rate of dissolved oxygen depletion can then be calculated.
This rate can be useful in designing aeration systems if this is a chosen manage-
ment option. The rate of dissolved oxygen depletion is also another indicator of
the severity of the lake trophic condition. Generally, the more rapid the depletion
rate, the more eutrophic the lake.
Low dissolved oxygen may be the cause of both summer and winter fishkills.
During summer months, the dissolved oxygen in shallow eutrophic lakes may be
depleted following a rapid algal die-off. Severe dissolved oxygen depletions can
occur from natural causes, but they can also result from unwise management;
for instance, treating an algal bloom in the entire lake with herbicides can drasti-
cally reduce the dissolved oxygen and cause a fishkill. Also, for lakes that freeze
at the surface during the winter months, dissolved oxygen can be reduced by
the end of winter to conditions that cause a fishkill.
Nutrients

The nutrients to be sampled in a lake study are generally those that are critical to
plant growth, principally phosphorus and nitrogen. Phosphorus is often the key
nutrient in determining the quantity of algae in the lake. Chapter 2 explained the
role of plant nutrients and their relative availability in lake systems. Certain
species of algae can fix atmospheric nitrogen and add to a lake's nitrogen pool if
nitrogen is in short supply. For eutrophication studies, total phosphorus is the
single most important nutrient to determine in the incoming and outgoing
streams. Many lake management decisions will be made based on the total
phosphorus income to a lake. The modeling efforts (see Chapter 4) to predict
water quality changes as a result of an implementation project are based on the
total phosphorus loadings. Other chemical analyses that are important are total
soluble phosphorus, soluble reactive phosphorus, total Kjeldahl nitrogen, nitrate
nitrogen, ammonium nitrogen, and total and dissolved solids. Occasionally,
measurements of chloride or potassium are useful indicators of agricultural or
urban source problems.
The total nitrogen to total phosphorus ratio (N:P) in the lake water can help
determine what algae might prevail in the lake (e.g., N:P 10). For example,
nitrogen-fixing blue-green algae might be favored during periods of low nitrogen
content in the lake. Since phosphorus is not a volatile chemical, its sources are
rather limited. Because of this, controlling phosphorus is usually the only practi-
cal solution to the problems of algal growth in a lake.
Of specific interest is the nutrient load during normal streamflow and the
nutrient income during storm events. A single, large storm event may produce a
nutrient income equal to several months of income during normal flow. To obtain
nutrient samples during storm events, automatic sampling devices that are ac-
tivated by rising water levels can be installed in the streams. The automatic
samplers are made for convenience, since the physical presence of a person to
obtain samples throughout a storm event is often not probable, especially when
the storm starts at 3 a.m. on Sunday morning.
The final component of the stream work is the coupling of the nutrient con-
centrations in the stream water to the streamflow to develop an annual nutrient
income to the lake. Once the annual nutrient and water income for the monitored
subbasins within the watershed have been calculated, they can be extrapolated
to the unmonitored subbasins. In the final analysis, the incomes from all of the
subbasins are added together to produce the total surface watershed income to
the lake.
3-18
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Biological Parameters
Biological indicators of eutrophication can be a variety of different organisms,
but the most frequently monitored indicators are algae and macrophytes
(weeds). An overabundance of either usually brings numerous complaints from
lake users.
Algal Biomass
Biomass determinations are probably the most useful measurement of the
amount of algae, followed by actual identification of species. The biomass
measurement most frequently used is chlorophyll-a. In most studies, an in-
tegrated water sample is collected from the upper portion of the lake (the photic,
or lighted, zone) either by taking water samples from several depths and mixing
them together, or by using a tube that extends through the photic zone. Peak
chlorophyll-a concentrations in an oligotrophic lake may range from 1.5 to
10.5 jig/L, while peak concentrations in a eutrophic lake may range from 10 to
275 p,g/L The average summer chlorophyll concentrations are good indicators
of the severity of the algal problems in a lake.
Algal identification also can be useful in conjunction with the biomass
measurements. A determination of the major types of algae that compose the
biomass may help to understand the lake problems. Blue-green algae are the
most frequent cause of aesthetic problems; they can float at the surface and
leave a paint-like film on the shores and cause taste and odor problems.
The chlorophyll-a concentrations and the relation to the major algal types
during the growing season are illustrated for eutrophic North Twin Lake in Figure
3-8. The period of greatest algal problems can be noted by the higher
chlorophyll-a concentrations from the end of July through September. The exact
kinds of algae that contribute to the higher biomass is displayed in the kite
diagrams of algal succession. Anabaena, a blue-green alga that often forms
noxious scum at the surface of the lake, is present during the August bloom.
Lyngbya, another troublesome blue-green alga, was dominant during Septem-
ber. The chlorophyll-a concentrations detailed the severity of the algal problem
and the algal identification allowed for the recognition of the algal species that
dominated during the problem period.
Chlorophyll-a: A type of
chlorophyll present in all
types of algae, sometimes
in direct proportion to the
biomass of algae.
Macrophyte Biomass and

Locations
Aquatic macrophyte communities range from completely submerged stands of
large algae (for example, Chara, Cladophora) to stands of rooted plants with
floating leaves (waterlily). Macrophyte densities vary seasonally, between lakes
in an area, and among regions. In a northern Wisconsin lake, the average weight
of macrophytes might be several hundred pounds per acre while in Florida
several tons per acre are common. Densities also vary within a lake. Eutrophic
lakes can have very high quantities of plants as can lakes located in regions with
long growing seasons, warm waters, or other favorable conditions.
Macrophytes are usually surveyed once or twice during the growing season.
Several tasks are normally accomplished during a macrophyte survey. The first
is mapping the location and extent of the major community types: emergents,
3-19
-------
Hydrographic map: A map
showing the location of ar-
eas or objects within a lake.
Q.
O
o
40
30
20
10

1
ah ll

|
M
A S 0
4000
cells/ml
2000
cells/ml
200 r
colonies/ml [_
(BG) =
BLUE-GREEN ALGAE
Anabaena
(BG)
Oscillatoria
(BG)
Lyngbya
(BG)
Fragilaria
(DIATOM)
Melosira
(DIATOM)
Microcystis
(BG)
M
A S ' 0
Figure 3-8.-The chlorophyll-a concentrations and the major algal types during the growing
season for the eutrophic North Twin Lake. The period of greatest algal problems can be
noted by the higher chlorophyll-a concentrations, end of July through September. The exact
kinds of algae that contribute to the higher biomass is displayed in the kite diagrams of algal
succession.

floating leaves, and submergent plants (see Biology of Macrophytes in Chapter
6). The abundance could be described as follows: A = abundant, B = common,
S = sparse. This information should be sketched on a hydrographic map to
show distribution of the major communities. Figure 3-9 is an example from Pike
Lake that shows the distribution patterns of the major macrophyte communities
during August. Then, plant density, species identification frequency, and depth
of growth should be determined.
3-20
-------
Pike Lake

August 14, 1980
Ceratophyllum

Utnculana — Potamogeton

Potamogeton — Mynophyllum — Utnculana

Ceratophyllum — Mynophyllum

Ceratophyllum — Potamogeton — Mynophyllum

Ceratophyllum — Potamogeton — Vallisnena
Figure 3-9.-Pike Lake distribution patterns of the major macrophyte communities during
August. Depth contours are given in meters.

The assembled information on macrophytes is useful in deciding where to
concentrate macrophyte control efforts, such as harvesting or dredging, and for
predicting the depth to which plants might grow if the water clarity were im-
proved (see Chapter 6).
Use of Trophic State Indices
A variety of indices are available to rate measured in-lake variables on a scale so
that the severity of lake problems can be compared to other lakes in the area.
This provides a quantitative means of assessing lake changes after protection
and restoration practices have been implemented (Carlson, 1977; Kratzer and
Brezonik, 1981; Walker, 1984). These lake indices, often referred to as "trophic
state indices," attempt to simplify complicated environmental measurements. As
Reckhow (1979) has pointed out, an index is a summary statistic that is used be-
cause its convenience outweighs the disadvantage of information lost in sum-
marization.
The basis for the trophic state index concept is that, in many lakes, the de-
gree of eutrophication is believed to be related largely to increased nutrient con-
centrations in the lake. Often phosphorus is the nutrient of concern. An increase
in lake phosphorus concentration is expected to cause an increase in the
amount of lake algae (see Chapter 2 to review this concept) as measured by
chlorophyll-a. Simultaneously there would be an associated decrease in water
transparency as measured by a Secchi disk.
The Carlson (1977) Trophic State Index (TSI), is the most widely used (see
Chapter 4). It was developed to compare determinations of chlorophyll-a, Sec-
chi transparency, and total phosphorus concentration. Higher index numbers in-
dicate a degree of eutrophy while low numbers indicate a degree of oligotrophy
(low nutrient and algal concentrations and high transparency). The index was
scaled so that a TSI = 0 represents a Secchi disk transparency of 64 meters.
Each halving of transparency represents an increase of 10 TSI units. A TSI of 50,
thus, represents a transparency of 2 meters, the approximate demarcation be-
3-21
-------
tween oligotrophic and eutrophic lakes. Suppose that a lake had a transparency
index of 60 prior to implementation of lake restoration. If two years later, the
index is 40, this would be a quantitative estimate of the degree of improvement.
A TSI of 40 might be common to undeveloped lakes in the area; this might indi-
cate that the lake has improved about as far as it can. Significant upward move-
ment of the index in later years would indicate a return of the lake to its previous
condition. The index, therefore, is a useful tool for assessing the lake's current
condition and for monitoring change over time.
The Carlson TSI works well in north temperate lakes that are phosphorus
limited but poorly in lakes that are turbid from erosion or in lakes with extensive
weed problems. Figure 3-10 is an example of TSI plots for a north temperate lake
of relatively poor water quality; Figure 3-11 illustrates a more complex situation
when it is necessary to determine why parameters do not agree as expected. By
scanning the TSI plots, the lake manager can begin to understand the patterns in
a particular lake and appreciate the seasonal variations that occur without
having to analyze phytoplankton and phosphorus concentrations and place
trophic interpretations on them.
100
90
(75 70
I 60
_c
8 50
£ 40
Q.
O
£ 30

0
Secchi depth
Chlorophyll-a
Total phosphorus
Mesotrophic
a
o
•»-»
LU
O

a.
o
^
4-<
O
05
M
A

1979
0
N
Figure 3-10.-A TSI plot for a north temperate lake that is considered of poor water quality.
3-22
The TSI values calculated for chlorophyll-a, for example, may not be similar to
simultaneous calculations of TSI from Secchi disk or total phosphorus measure-
ments. Understanding this particular situation requires the consultant to examine
the data base in greater detail. In this case, an explanation might be the
presence of suspended materials that reduce light attenuation and therefore
algal productivity. An abundant population of large zooplankton might be active-
ly feeding upon the algae and reducing their biomass. In such cases, the TSI
-------
x
CD
T3
C
to
ffi
O

Q.
O
80

10
..-^.
D TSI (Total - P)
O TSI (Secchi Disk)
A TSI (Chlorophyll-a)
I
I
I
.O

Q.
O
+-*
O
D)
M
J A
Months
0
Figure 3-11.-A TSI plot that adds more complexity to the interpretation. The TSI(chl-a) plot
does not agree with either the TSI(SD) or the TSI(TP) plots. Understanding this particular
situation requires the lake manager to examine the data base in much greater detail.

plots would be valuable because they allow the professional to assess the situa-
tion, and the possible need for additional information, in order to make
decisions.
Other indices have been developed that are more appropriate for the various
major lake ecoregions in the country. Walker (1984) has developed such an
index for reservoirs, and Brezonik (1984) has developed an index that more
specifically fits the needs of Florida lakes and includes situations where nitrogen
rather than phosphorus may be limiting algal growth. Porcella et al. (1979) have
included a term in their Lake Evaluation Index that represents the amount of lake
surface covered by macrophytes.
Problem Definition

Putting the Pieces of the Puzzle
Together
Identifying lake problems is not that difficult; identifying the source of a particular
problem takes a little more effort. The in-lake and watershed measurements
necessary to identify the severity of a problem and track down the sources that
cause various problems have been discussed. The final step is to use the infor-
3-23
-------
mation to make lake management decisions. The best way to illustrate the im-
portance of measuring the severity of the lake problem and identifying the sour-
ces is to present an example.
Mirror Lake

Mirror Lake is a small urban lake located within the city limits of Waupaca, Wis-
consin. The lake has a surface area of 12.5 acres and a maximum depth of 43
feet. The lake had experienced repeated blue-green algal blooms and winter
fishkills. The city had an interest in restoring the lake.
A diagnostic study was designed to determine the annual incomes of water
and total phosphorus and to examine the water quality condition of the lake. Mir-
ror Lake is a seepage lake without permanent inflowing streams from the water-
shed. If this had been a drainage lake, then considerable attention would have
been paid to land uses, and to streamflows, in order to identify those areas of the
watershed most responsible for the silt and nutrient loads causing the problem.
Water and nutrient incomes were studied during 1972 and 1973. Table 3-4
lists the results. Storm sewers from the City contributed more than 50 percent of
the phosphorus income to Mirror Lake and were the obvious targets for lake
protection efforts. The study demonstrated that the greatest periods of phos-
phorus income were spring showers and during intense late summer rainfalls.
Table 3-4.—Annual phosphorus budget for Mirror Lake, 1972 and 1973
SOURCES ^> ~
1972
%
Storm Sewers
Diffuse
Ground Water
Atmospheric
50
16
21
14
101
57
21
18
4
100
Internal nutrient cycling:
Transformation of nutrients
such as nitrogen or phos-
phorus from biological to in-
organic forms through de-
composition, occurring
within the lake itself.
3-24
Total phosphorus concentration in the lake averaged 90 ^g phosphorus/liter,
a very high value. The Carlson Trophic State (TSI) index number for this total
phosphorus concentrations was 69, a value expected for an extremely eutrophic
lake. Measurements of phosphorus throughout the water column revealed ex-
tremely high phosphorus concentrations in the hypolimnion, particularly near
the sediments. Experiments were then conducted to determine whether this
phosphorus came from the sediments. The results revealed a very high release
rate or internal phosphorus loading from the sediments.
The algae in the lake during the summer were unlike those found in many
other eutrophic lakes. The spring and fall months were characterized by massive
blooms of a blue-green algae called Oscillatoria agardhii, but the summer
season saw this species confined to the metalimnion (see Chapter 2), while the
upper waters were dominated by green algae.
It became obvious that the year-to-year increase in the quantity of algae of
Mirror Lake was a response to stormwater inputs. A sediment core was taken,
dated with the Lead-210 techniques, and analyzed for the presence of particular
types of chlorophyll pigments common in Oscillatoria. The first bloom of algae,
as recorded by pigments in the sediments, occurred in the early 1940's, just a
few years after storm drainage was diverted to the lake.
The diagnostic study demonstrated very low dissolved oxygen in Mirror Lake
during the winter (Fig. 3-9). This problem was the cause of winter fishkills. An
analysis of the data revealed that this problem was due to poor lake mixing
during fall months (see Chapter 2, for a discussion of expected thermal histories
-------
of lakes) before ice developed. This meant that the lake had very low dissolved
oxygen in it when the ice formed on the lake surface and eliminated oxygen ex-
change with the atmosphere.
The data from the diagnostic study were used to determine appropriate lake
protection and restoration strategies. In 1976, storm sewer diversion reduced
the phosphorus income to the lake by 50-60 percent. This step was taken after
an historical analysis of lake sediments showed a relationship between the onset
of algal blooms and the beginning of stormwater discharge to the lake. There
was every expectation among lake users that the lake would immediately im-
prove. As shown in Figure 3-11, total phosphorus concentration in the lake in
1977 and part of 1978 was very similar to the prediversion average of 90 n,g
phosphorus per liter. This result demonstrated that storm sewer diversion was a
necessary step to lake protection, but an insufficient one for lake restoration.
The high internal phosphorus release was recycling phosphorus stored in the
sediments from the 35 years of storm drainage. These phosphorus-rich waters
were probably transported from the bottom to the upper waters during summer
storm mixing. This mixing helped to maintain high phosphorus levels in the
water column. This problem was identified because monitoring had continued
after storm sewer diversions. This post-diversion monitoring was an integral part
of diagnosis and implementation (see Chapter 8).
Aluminum sulfate was applied to Mirror Lake sediments in May, 1978 to "inac-
tivate" this phosphorus release (see Chapter 6 for a more detailed discussion of
this procedure). As shown in Figure 3-12, total phosphorus fell to about 20 ^g
phosphorus per liter, and has remained at that low level for several years. This
action produced a total phosphorus TSI of about 47, a value found in lakes
that are considered to be borderline eutrophic. A lake with this total phosphorus
concentration would be expected to have fewer problems with algae and sharp-
ly improved transparency. This is what happened. Osc/llatoria agardhii was not
present by 1980.
The problem with low dissolved oxygen under the ice was solved by using an
artificial circulation device (see Chapter 6) in the fall to thoroughly mix the lake.
Figure 3-13 shows the success of the treatment. The threat of a winter fishkill
was ended.
This case history represents a real and highly successful use of the diagnosis-
feasibility-implementation approach to lake protection and restoration. The city,
and its consultants, looked for the causes of the problem. The continued wast-
ing of money on temporarily effective treatments was replaced with expendi-
tures directed toward the long term solution of the problem. Had the obvious
just been done (stormwater diversion only), the lake would have taken years to
flush out nutrients before it came to a new average total phosphorus concentra-
tion. Instead, the consultants identified a second source of phosphorus and
treated that as well. The lesson here is that lake management proceeds from
step-by-step approaches that are based upon a knowledge of both the water-
shed and the lake, and are directed at the causes of the lake's problems. Effec-
tive lake management plans (see Chapters 7, 8, and 9) result from the integration
of watershed management practices (see Chapter 5) and in-lake restoration pro-
cedures (see Chapter 6).
3-25
-------
O.Mr-
Mirror Lake
Phosphorus
Dissolved Reactive Phosphorus
0.02
I I I I I I I I 1 U«sJ
I
I I I I I I I
10 12 2 4 6 8 10 12 2 4 6 3
1977 1978
10 12 2 4 6 8 10 12 2 4 6 8
1979 1980
10 12 2 4
1981
6 8 10
Figure 3-12.-Phosphorus concentrations in Mirror Lake water decreased dramatically following alum treatment.
(O
CM
A
-------
Mirror Lake
Dissolved oxygen (mg/L)
ice
AMJ JASON
aeration
aeration
D J FMAMJ

1978

aeration
JASON
aeration
DJ FMAMJ JASON
Figure 3-13.-Oxygen concentrations in Mirror Lake before and atter aeration show that both
the duration and severity of anoxia decreased. Oxygen concentrations are indicated by the
numbers on the lines (isopleths). 0 indicates no oxygen.
3-27
-------
APPENDIX 3-A
Democratic Procedures to

Obtain Consensus on Priority

Uses for a Lake

Nominal Group Process

The nominal group process is an alternative to the standard group meeting pro-
cedure. In a typical group meeting, a decision is made through the following se-
quence: a motion, discussion, and a vote. This standard procedure is frustrating
to most people because they feel intimidated about speaking up in a group set-
ting or because discussion is monopolized by a few dominant personalities.
The nominal group process is especially effective at soliciting concerns or
setting priorities. It can also be used to solicit ideas for activities or projects.
Thus, the nominal group process could be used to prioritize uses, enumerate
and prioritize perceived problems, or prioritize projects for a lake organization.
The process has many variations. In its simplest form, each participant is first
asked to write down a list of issues. The moderator than asks each person to
volunteer one issue from that person's list. The moderator proceeds around the
group until all issues are transferred from individual written lists to sheets of
paper hung in view of the group. During this time, there is no discussion or
debate on the appropriateness of anyone's suggestion. Each participant decides
whether his or her issues are already listed on the sheet. The moderator
proceeds around the group until no one has any more issues to contribute.
After all issues are listed, the group debates whether certain issues should be
combined. The discussion on combining issues usually leads into a general dis-
cussion of the issues. The discussion is led by the person who suggested the
issue and is designed to help others understand the issue more fully. The
moderator must be forceful in keeping the discussion focused on understanding
each issue and eliminating duplication if the "authors" of those issues agree. The
discussion is not allowed to become a debate on the merits of the issue.
Following the discussion, the moderator allows each person to select a
limited number of issues to "save" by placing a mark or sticker next to those is-
sues. (The physical act of getting up and placing marks provides a nice, refresh-
ing break in the process.) The 3-10 issues with the largest number of votes are
placed by the moderator into a priority pool. Participants then rank those issues.
The nominal group method is designed to allow equal participation by all
members of the group. Dominant personalities are neutralized by the procedure.
If a group exceeds 15 people, it is advisable to split the group into smaller sub-
groups and proceed until each subgroup has identified its priority pool. The
priority pools are then combined and the entire group ranks the issues in the
combined pool.
In larger lakeshore communities, direct participation by all property owners
and local lake users may not be feasible. Under such circumstances a task force
or advisory committee might serve to represent the community and report to a
city council or county board. The nominal group process may still be a useful
procedure for the task force or advisory committee itself to use.
3-28
-------
In addition to identifying issues, the participants leave the process with a
much higher sense of ownership than they do after participating in a standard
meeting. After the nominal group experience, they identify with the priorities be-
cause they actively help to select them.
Delphi Process
The Delphi technique is premised on incomplete knowledge an inherent bias by
any one expert (or citizen). Therefore a panel of experts is expected to produce
a more complete range of issues or solutions and a more balanced prioritization
than a single expert.
This procedure is useful in setting research priorities, summarizing current
knowledge, and making policy recommendations for public bodies. For in-
stance, it could be used to design a management plan for a new reservoir.
The first stage of the process is a solicitation of the full range of issues, ideas,
and concerns associated with the topic. The experts at a meeting or through
correspondence simply provide a "laundry list" of all items that might be ap-
propriate.
In the second stage, the list developed in Phase I is provided to the same ex-
perts for a ranking on some specified criterion of importance. The results of
Phase II are communicated to the organization that initiated the effort. Additional
phases can be used to obtain greater specificity regarding the highest ranked
items.
While this procedure is too complicated and expensive for most lakeshore
communities, it is often a good idea for lake organizations to get a second
opinion on major recommendations they receive from a consultant or agency
employee.
Literature Cited
Delbecq, Andre I., Andrew H. VanDeVer, and David H. Gustafson. 1975. Group
Techniques for Program Planning: A Guide to Nominal Group and Delphi
Processes. Scott, Foreman, and Co. Glenville, IL.
3-29
-------
CHAPTER 4
Predicting Lake Water
Quality
-------
CHAPTER 4

PREDICTING LAKE WATER

QUALITY

Uses of Models
Mathematical models can be useful both in diagnosing lake problems and in
evaluating alternative solutions. They represent the cause-effect relationships
that control lake water quality in quantitative terms. Model formulas are derived
from scientific theories and from observations of the processes and responses
in real lakes. There are two basic ways in which models can be employed in lake
studies:
1. DIAGNOSTIC MODE: What is going on in the lake? Models provide a
frame of reference for interpreting lake and watershed monitoring data. They tell
the user what to expect to find in a lake with a given set of morphometric,
hydrologic, and watershed characteristics. These expectations are not always
met, however. Differences between measured and predicted conditions contain
information on the unique features of the lake under study. They help clarify im-
portant cause and effect relationships.
2. PREDICTIVE MODE: What will happen to the lake if we do this, that, or
the other thing? Models can be used to predict how lake water quality condi-
tions will change in response to changes in nutrient inputs or other controlling
factors. For practical reasons, it is usually infeasible to predict lake responses
based on full-scale experimentation with the lake and its watershed. Instead,
mathematical models permit experiments to be performed on paper or on com-
puter.
Examples of questions that might be addressed via lake modeling include

• What did the lake look like before anyone arrived?

• What level of nutrient loading can the lake tolerate before it develops
algae problems?
Morphometry: Relating to
a lake's physical structure
(e.g. depth, shoreline
length).
4-1
-------
• How will future watershed development plans affect the lake's water
quality?
• What are the most important sources of the lake's problems?
• What reduction in nutrient loading is needed to eliminate nuisance algal
blooms in the lake?
• Once watershed or point-source controls are in place, how long will it
take for lake water quality to improve?
• Given monitoring data collected in the lake and its watershed during a
given year, what is the expected range of water quality conditions over
several years?
• Given a water quality management goal (such as a target level of lake
phosphorus, chlorophyll-a, or transparency) and an array of feasible
control techniques, what is the probability that restoration efforts will be
successful?
• Are proposed lake management goals realistic?

Models are not the only means of addressing these questions, and they do
have limitations. For example, modeling is feasible only for evaluating those
types of problems that are understood well enough to be expressed in concise,
quantitative terms. In some situations, modeling may be infeasible or unneces-
sary. Why make a lake study more complicated than it has to be?
Models are not monoliths. They are rather frail tools used by lake manage-
ment consultants in developing their professional opinions and recommenda-
tions. The consultant should decide which models (if any) are appropriate, what
supporting data should be collected, how the models should be implemented,
and how the model's results should be interpreted. Consider the following
analogy:
HOME ADDITION LAKE STUDY
Carpenter Consultant
Tools Modeling Techniques
Raw Materials Monitoring Data
Different carpenters may prefer certain brands of tools to others. The selec-
tion of appropriate tools to accomplish a given job is important, but not the only
factor determining the success or failure of a project. In home building, the
quality of the addition depends less upon which tools are used than upon how
they are used. The owner hires the carpenter, not his or her tools. The same is
true for hiring a lake management consultant. Obviously, the quantity and quality
of raw materials are every bit as important as the tools used on the job. The raw
materials required for applying a model to a lake are monitoring data and other
baseline information developed under diagnostic studies (Chapter 3).
For ease in explaining modeling concepts, English units are used in the ex-
amples in this chapter. Lake modeling is far less awkward, however, when metric
units are used.
4-2
-------
Eutrophication Model

Framework
Phosphorus loading models are frequently used to evaluate eutrophication
problems related to algae. These models link phosphorus loading to the average
total phosphorus concentration in the lake water and to other indicators of water
quality that are related to algal growth, such as chlorophyll and transparency
(Fig. 4-1). Lake responses to phosphorus loading depend upon physical and
hydrologic characteristics. Therefore, these models consider lake volume,
average depth, flushing rate, and other characteristics in predicting lake respon-
ses to a given phosphorus load.
While the terms and equations involved may seem mystical, the underlying
concepts are simple:
1. Lake algal growth is limited by the supply of phosphorus.
2. Increasing or decreasing the mass of phosphorus discharged into the lake
over an annual or seasonal time scale will increase or decrease the average con-
centrations of phosphorus and algae in the lake.
3. A lake's capacity to handle phosphorus loadings without experiencing
nuisance algal blooms increases with volume, depth, and flushing rate.
In other words, the lake's condition depends upon how much phosphorus it
receives from both internal and external sources. A large, deep lake with a high
flow will be able to handle a much greater phosphorus load without noticeable
deterioration, compared with a small, shallow, or stagnant lake. Models sum-
marize these relationships in mathematical terms, based upon observed water
quality responses of large numbers of lakes and reservoirs.
Algal growth in these models is usually expressed in terms of mean, growing-
season chlorophyll in the epilimnion concentrations. As discussed in Chapter 3,
phosphorus, chlorophyll-a, and transparency help to define trophic state, a
vague concept used to characterize lake condition. Other variables related to
algal productivity, such as hypolimnetic oxygen-depletion rate, seasonal maxi-
mum chlorophylls, bloom frequency, or organic carbon, may also be con-
sidered in phosphorus loading models.
These methods cannot yet be used to predict aquatic weed densities, which
generally depend more upon lake depth, the quantity and quality of lake bottom
sediment, and light penetration than upon the loading of nutrients entering the
lake from its watershed.
Eutrophication models rely heavily on the lake phosphorus budget, which is
simply an itemized accounting of the inputs and outputs of phosphorus to and
from the lake water column over a year or growing season. Although budgets
can be constructed for other pollutants that cause lake problems (nitrogen, silt,
organic matter, bacteria, or toxics, for example) phosphorus budgets are used
most frequently. A phosphorus budget provides a means to evaluate and rank
phosphorus sources that may contribute to an algal problem. The basic concept
and mathematics are relatively simple, although the estimation of individual
budget items often requires considerable time, monitoring data, and expertise.
Basic concepts involved in constructing phosphorus budgets and applying
eutrophication models are described and illustrated in later sections of this
chapter. In some situations, particularly in reservoirs, algal growth may be con-
trolled by factors other than phosphorus, such as nitrogen, light, or flushing rate
(Walker, 1985). Models appropriate for these situations are more complex than
those discussed below, although the general concepts and approaches are
similar.
4-3
-------
Eutrophication Model Concepts
Loading:
Modifying factors
Phosphorus loading
Morphometry
Hydrology
Other factors

Increase
concentration
(Limiting nutrient)

Promote algal growth
and increase
concentration
(Algal pigment)

Decrease water
*• Transparency
(Secchi depth)
Factors modifying
lake response
to loading
Patterns of
response
High
• response
factors
Low
response
factors
Lake phosphorus

High vflfn :|:|
Low ^

Phosphorus loading

Small, stagnant
Shallow
Dissolved P load
Sediment recycle

Large, rapidly-flushed
• Deep
Particulate P load
Stable thermocline
Chlorophyll-a_
Lake Phosphorus

Clear, stagnant
Shallow
Dissolved P load
Turbid, rapidly-flushed
• Deep
Particulate P load
Nitrogen limited
Zooplankton grazing
Transparency
Low
Chlorophyll-a_
Turbid, colored
- High silt
Rapidly-flushed
Shallow
Figure 4-1.-Eutrophication modeling concepts.
-------
Variability
Eutrophication models are geared to predicting average water quality conditions
over a growing season or year. Unfortunately, this often gives the mistaken im-
pression that water quality is fixed and does not vary in different areas or
through time within a given lake. This is not the case. Averaging is typically done
over three dimensions:
1. Over Depth. Generally within the surface, mixed layer. Vertical variations
within the mixed layer are usually small.
2. Over Sampling Stations. Sampling station locations might be located in
different places of the lake. In a small, round lake, the variations among sampling
stations will tend to be insignificant, and one station is usually adequate. In a
large lake with several embayments, in a long, narrow reservoir, or in a complex
reservoir with several tributary arms, however, water quality may vary significant-
ly from station to station (from oligotrophic to hypereutrophic). In such situa-
tions, the "average water quality" may be meaningless, and it may be
appropriate to divide the lake or reservoir into segments for modeling purposes
(outflow from one segment serves as inflow to the next).
3. Over Season. Phosphorus, transparency, and especially chlorophyll-a
concentrations usually vary significantly at a given station from one sampling
date to the next during the growing season. It is not unusual, for example, for the
maximum chlorophyll-a concentration to exceed two to three times the seasonal
average. Because the input data themselves represent values within a range of
actual conditions, model outputs also should be considered to represent
answers within a range. Thus, model calculations are generally reported as
having a certain "percent confidence" to indicate the likelihood that the answer is
correct within a given range.
In addition, since chlorophyll-a, phosphorus, and transparency vary during
the season to begin with, a slight improvement or deterioration in these water
quality characteristics is difficult to perceive. A model prediction that conditions
would improve slightly, therefore, is not likely to represent a noticeable change
in the lake. When the change becomes comparable to normal variations, it is
easier to observe an improvement or deterioration.
Because of the above sources of variability, it is more realistic to consider
measured or modeled water quality as a "smear" than as a "point." If a consultant
says that a lake has a mean chlorophyll-a concentration of 10 ppb, for example,
the actual mean may be 5 or 20 ppb, depending on monitoring frequency and
lake variability. Perhaps more important, even if the seasonal mean is 10 ppb, 90
percent of the samples will be in the 2-to-24 ppb range for a lake with typical
seasonal variability.
In a given watershed and lake, year-to-year variations in average water quality
may be significant because of fluctuations in climatologic factors, particularly
streamflows and factors controlling thermal stratification. Monitoring programs
extending for a period of at least 3 years are often recommended to characterize
this year-to-year variability and provide an adequate basis for lake diagnosis and
modeling.
Another source of variability is model error. Statistical analyses of data from
large numbers of lakes and reservoirs indicate that phosphorus loading models
generally predict average lake responses to within a range of one to two times
the average. Differences between observed and predicted water quality, in part,
reflect variability in the data (loading estimates and observed lake responses)
and inherent model limitations. Differences between observed (directly
measured) and predicted (modeled) values may contain useful information for
diagnostic purposes, however. Model projections of future conditions resulting
4-5
-------
from a change in phosphorus loading are more reliable when they are expressed
in relative terms (percent change from existing conditions). A good lake and
watershed monitoring program can reduce the risk of significant model errors,
which may lead to false conclusions and poor management decisions.
Loading Concept
Loadings most accurately express the relative impacts of various watershed
sources on lake water quality. For example, a stream with high phosphorus con-
centration will not necessarily be an important source to the lake, because the
stream may have a very low flow and, therefore, contribute a relatively low an-
nual loading.
Because lakes store nutrients in their water columns and bottom sediments,
water quality responses are related to the total nutrient loading that occurs over
a year or growing season. For this reason, water and phosphorus budgets are
generally calculated on an annual or seasonal basis. Water and phosphorus
residence times in the water column determine whether seasonal or annual
budgets are appropriate for evaluation of a given lake.
Phosphorus loading concepts can be illustrated with the following analogy:
GROCERY BILL PHOSPHORUS LOADING
Item Source
Quantity Flow
Unit Cost Concentration
Cost of Item Loading From Source
Total Cost of All Items Total Loading From All Sources
The cost of a given item is determined by the quantity purchased and the unit
cost. The total cost of all items purchased determines the impact on finances
(lake water quality). Funds (lake capacity to handle phosphorus loading without
water quality impairment) are limited. Therefore, intelligent shopping (managing
the watershed and other phosphorus sources) is required to protect finances
(lake water quality).
Loadings change in response to season, storm events, upstream point sour-
ces, and land use changes. For example, converting an acre of forest into urban
land use typically increases the loading of phosphorus by a factor of 5-20. This
results from increases in both water flow (runoff from impervious surfaces) and
nutrient concentration (phosphorus deposition and washoff from impervious
surfaces). The evaluation of loadings provides a basis for projecting lake respon-
ses to changes in land use or other factors.
The grocery bill analogy breaks down in at least one important respect: Shop-
pers can read the unit costs off the shelves. To estimate phosphorus loading
from a given source, both flow and concentration must be quantified over annual
and seasonal periods. This is difficult because both flow and concentration vary
(much more than supermarket prices) in response to season, storm events, and
other random factors. Flow should be monitored continuously in major streams.
Concentration is usually sampled periodically (weekly, monthly) and preferably
supplemented with samples taken during storms. This is why good lake and
watershed studies cost so much. Particularly in small, flashy streams, a very high
percentage of the annual loading may occur during short, intense storms. If
4-6
-------
these events are not sampled, it will be relatively difficult to develop reliable load-
ing estimates.
Because of these factors, loading estimates for each source should be con-
sidered with a degree of skepticism. These are not fixed quantities but ranges.
Depending upon monitoring intensity and calculation methods, an annual load-
ing estimate for a given stream could be off by a factor of two or more. Where
appropriate, monitoring intensity can be increased to provide better data for
quantifying loadings, particularly in streams that are thought to be major con-
tributors.
Water Budget
The first step in lake modeling is to establish a water balance. Flows carry pol-
lutants into and out of lakes, and analyses of lake eutrophication and most other
water quality problems cannot be conducted without a quantitative under-
standing of lake hydrology. The basic water balance equation considers the fol-
lowing flow terms, typically in units of acre-feet per year:

INFLOW + PRECIPITATION = OUTFLOW + EVAPORATION +
CHANGE IN STORAGE

Water budget concepts are illustrated in Figure 4-2.

LAKE WATER BUDGET
PRECIPITATION EVAPORATION
TRIBUTARY INFLOWS . I t -^. WITHDRAWALS

X| ' 1/
DIRECT RUNOFF ^ CHANGE IN STORAGE Y ^_^ SURFACE OUTFLOW
POINT-SOURCE
DISCHARGES

GROUNDWATER INFLOWS " \_ ^^ ^\_*. GROUNDWATER OUTFLOWS

Figure 4-2.-Water budget schematic.

The data for the terms INFLOW and OUTFLOW should be evaluated over an-
nual or seasonal periods. Inflows may include tributary streams, point-source
discharges, runoff from shoreline areas, and groundwater springs. Outflows may
include the lake outlet; groundwater discharges; and withdrawals for water
supply, irrigation, or other purposes. Major inflow and outflow streams should be
gaged directly. Indirect estimation procedures (for example, runoff coefficients)
can be used to quantify smaller streams. Precipitation and evaporation can be
derived from regional climatologic data. The CHANGE IN STORAGE accounts
for changes in surface elevation over the study period, which is sometimes sig-
nificant in reservoirs. This term is positive if lake volume increases over the study
period, negative otherwise.
Once the flow terms have been estimated and tabulated, the water balance
should be checked by comparing the total inflows (left side of equation) with
total outflows (right side). Major discrepancies may indicate an omission or es-
timation error in an important inflow or outflow term (such as unknown or poorly
defined streamflow or groundwater flow). Establishing water balances is relative-
ly difficult in seepage lakes because of the problems and expense of monitoring
groundwater flows. In any event, significant errors in the water balance may indi-
cate a need for further study of lake hydrology.
4-7
-------
To provide a complete accounting of the watershed, drainage areas should
also balance (that is, the sum of the tributary drainage areas plus the lake sur-
face area should equal the drainage area at the lake outlet).
Phosphorus Budget
The lake phosphorus budget (Fig.4-3) provides the cornerstone for evaluating
many eutrophication problems. The following terms are evaluated and typically
expressed in units of pounds per year:
INFLOW LOADING = OUTFLOW LOADING + NET SEDIMENTATION
+ CHANGE IN STORAGE
This equation summarizes fundamental cause and effect relationships linking
watersheds, lake processes, and water quality responses.
LAKE PHOSPHORUS BUDGET

PRECIPITATION
& DUSTFALL MIGRANT WATERFOWL

TRIBUTARY INFLOWS —, , I _*. WITHDRAWALS

DIRECT RUNOFF ^\ CHANGE IN STORAGE Y ^_+. SURFACE OUTFLOW
POINT-SOURCE
DISCHARGES

GROUNDWATER INFLOWS - ^ . ^
& SHORELINE SEPTIC TANKS ^~—* ^~*" GROUNDWATER OUTFLOWS

NET SEDIMENTATION

Figure 4-3.-Phosphorus budget schematic.
The INFLOW LOADING term is the sum of all external sources of phosphorus
to the lake, which may include tributary inflows, point sources discharging
directly to the lake, precipitation and dustfall, leachate from shoreline septic
tanks, other groundwater inputs, runoff from shoreline areas, and contributions
from migrant waterfowl. Estimation of individual loading terms is the most impor-
tant and generally most expensive step in the modeling process. Investments in
intensive monitoring programs to define and quantify major loading sources
usually pay off in terms of the quality and reliability of project results. Monitoring
of the lake itself is usually conducted during the same period so that loadings
can be related to lake responses.
Stream loadings, usually the largest sources, are estimated from streamflow
and phosphorus concentrations monitored over at least an annual period. Major
tributaries should be sampled just above the lake over a range of seasons and
flow regimes (including storm events) to provide adequate data for calculating
loadings. In large watersheds, it may be appropriate to sample at several
upstream locations so that contributions from individual point and nonpoint
sources can be quantified. Special studies may be required to estimate
groundwater input terms (for example, groundwater sampling and flow model-
ing, shoreline septic tank inventories). Loadings in runoff from shoreline areas
and from relatively small, unsampled tributaries can be estimated indirectly, as
discussed below. Loadings in precipitation and dustfall, usually relatively small,
can be estimated from literature values or regional sampling data.
4-8
-------
In many cases, indirect estimates of loading from a given stream or area can
be derived from information on watershed characteristics. This method is based
upon the concept that two watersheds in the same region and with similar land
use patterns and geology will tend to contribute the same loading of phos-
phorus per unit area. This permits extrapolation of data from one or more
monitored watersheds to others. "Export Coefficients" (Ibs phosphorus/acre-
yr) have been compiled for various land uses and regions (Chapter 2, see Table
2-1). The applicability of this method depends largely upon the quantity and
quality of regional export coefficient data for the land uses and watersheds
under study. This approach is much less costly than direct monitoring, but
generally less reliable. It is frequently used in preliminary studies (to get a rough
handle on the lake nutrient budget before designing and conducting intensive
monitoring programs) and for estimating loadings from small watersheds whose
contributions to the lake's total phosphorus budget are relatively insignificant.
The OUTFLOW LOADING term accounts for phosphorus leaving the lake in
surface outlet(s); withdrawals for water supply, irrigation, or other purposes; and
groundwater seepage. These are usually estimated by direct measurements of
flow and concentration, as described above for stream loadings. If the lake out-
flow is dominated by groundwater seepage, it will be very difficult to determine
the outflow loading term directly.
The NET SEDIMENTATION term accounts for the accumulation or retention
of phosphorus in lake bottom sediments. It reflects the net result of all physical,
chemical, and biological processes causing vertical transfer of phosphorus be-
tween the water column and lake bottom, as described in Chapter 2. For a given
loading, lake water quality will generally improve as the magnitude of the
sedimentation term increases because higher sedimentation leaves less phos-
phorus behind in the water column to stimulate algal growth. Because there are
several complex processes involved and these vary spatially and seasonally
within a given lake, it is generally infeasible to measure net sedimentation direct-
ly. Accordingly, this term is usually calculated by difference from the other terms
or estimated using empirical models of the type discussed in the next section.
The CHANGE IN STORAGE term accounts for changes in the total mass of
phosphorus stored in the lake water column between the beginning and end of
the study period. Such changes would reflect changes in lake volume, average
phosphorus concentration, or both. This term is positive if the phosphorus mass
increases over the study period, negative otherwise.
As formulated above, the water and phosphorus budgets provide important
descriptive information on factors influencing lake eutrophication. A useful for-
mat for presenting results of budget calculations is illustrated in Table 4-1, based
on data from Lake Morey, Vermont. The table provides a complete accounting
of drainage areas, flows, and loadings. The relative importance of various sour-
ces can be readily derived from the percentage calculations and accompanying
pie charts. The mean concentrations (ppb), runoff (ft/yr), and export (Ibs/acre-yr)
provide means for comparing the unit contributions from various watersheds of
different sizes. Often these values are sensitive to land uses, point sources, or
geologic factors. For example, the relatively high export value for Pine Brook
(.47 versus a range of .04-.21 Ibs/acre-year for the other watersheds) reflects
erodible soils. High export values for Aloha Camp and Bonnie Oaks Brooks
reflect inputs from camp sewage treatment systems.
Comparing the magnitudes of the individual loading terms provides a basis
for ranking sources and identifying possible candidates for watershed manage-
ment or point source control techniques. For example, the Lake Morey phos-
phorus budget (Table 4-1) clearly indicates that sewering of shoreline areas
would not be an effective means of reducing lake eutrophication because septic
tanks currently account for less than 1 percent of the total loading.
4-9
-------
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restoration technique such as sediment phosphorus inactivation (see Chapter 6)
may be appropriate for lake restoration.
4-11
-------
Lake Response Models
Having characterized water and phosphorus budgets under existing conditions,
response models can be used to evaluate existing lake conditions and to predict
changes in phosphorus, chlorophyll-a, and transparency likely to result from
changes in phosphorus loading. Several empirical models have been developed
for this purpose. These models are based on statistical analysis of monitoring
data from collections of lakes and reservoirs.
Models vary with respect to applicability, limitations, and data requirements.
The consultant's choice of appropriate models for a given lake or reservoir
should be based on regional experience and professional judgment. The con-
sultant should also consider how closely the impoundment characteristics (mor-
phometry, hydrology, lake versus reservoir) reflect the characteristics of the
lakes that were used to develop a model. It may be inappropriate, for example,
to apply a model developed in a study of Canadian natural lakes to an Alabama
reservoir with a very different set of conditions.
Eutrophication models are driven by three fundamental variables that are cal-
culated from impoundment morphometry, water budgets, and phosphorus
budgets:
(1) Pi = AVERAGE INFLOW PHOSPHORUS CONCENTRATION (PPB)

Total Phosphorus Loading (Ibs/yr)
— ______________________ ______
----- ------ -
Mean Outflow (acre-ft/yr)
OCQ
OLIO
This is the flow-weighted-average concentration of all sources contribut-
ing phosphorus to the impoundment. If there were no interactions with
bottom sediments, the average inflow, lake, and outflow phosphorus con-
centrations would be approximately equal. This basic measure of inflow
quality is the most important determinant of eutrophication response and
is the most frequent focus of long-term management efforts. It is sensitive
to watershed point and nonpoint sources.
Residence time: Com-
monly called the hydraulic
residence time-the amount
of time required to com-
pletely replace the lake's
current volume ofwaterwith
an equal volume of "new"
water.
(2) T = MEAN HYDRAULIC RESIDENCE TIME (YEARS)

Lake Volume (acre-ft)
Mean Outflow (acre-ft/yr)

This variable approximates the average length of time water spends in a
lake or impoundment before being discharged through the outlet. In other
terms, it equals the time required for the lake to refill if it were completely
drained. As residence time increases, interactions between the water
column and bottom sediment have greater influences on water quality.
For a given inflow concentration, phosphorus sedimentation usually in-
creases and lake phosphorus concentration decreases with increasing
residence time. At very short residence times (less than 1 -2 weeks), algae
may have inadequate time to respond to the inflowing nutrient supply.
4-12
-------
(3) Z = MEAN DEPTH (FEET)

Lake Volume (acre-ft)

Surface Area (acres)

Other factors being equal, lakes and impoundments with shallower mean
depths are generally more susceptible to eutrophication problems. Shal-
lower lakes have higher depth-averaged light intensities to support
photosynthesis and greater sediment/water contact, which can en-
courage nutrient recycling. Since they both increase with lake volume,
mean depth and hydraulic residence time are typically correlated.

Models differ with respect to how these variables are combined in equations
to predict lake or reservoir responses for nutrient loading.
One set of equations based on data from northern, natural lakes is presented
in Table 4-2 to illustrate modeling concepts. These are not necessarily the "best"
models to use in a given application, the choice of which should be left to the
lake consultant.

Table 4-2.—Typical phosphorus loading model equations for Northern lakes.

pi P Chl.-a

INFLOW ^PHOSPHORUS -» CHLOROPHYLL-a SECCHITRANSPARENCY
<1> (2) (3)

(1) A model for predicting lake phosphorus concentration was developed by Larsen and
Mercier (1976) and Vollenweider (1976):

P(ppb) = P,
1 + T5

This equation predicts that average lake phosphorus concentration, P, will increase
in proportion to the inflow concentration and will decrease with increasing hydraulic
residence time. At low residence times, phosphorus sedimentation is negligible and
the response is controlled primarily by inflow concentration.

(2) The simplest of the chlorophyll-a response models was developed by Carlson (1977).

Chi -a (ppb) = 068 P146

This equation is similar to others developed from northern lake data by Dillon and
Rigler (1974) and by Jones and Bachman (1978)

(3) A similar relationship was also developed by Carlson (1977) to predict Secchi disk
transparency:

Secchi (meters) = 7.7Chl-a~68

This equation is appropriate for lakes and reservoirs in which transparency is con-
trolled primarily by algae. It will overestimate transparency in impoundments with rela-
tively high concentrations of inorganic suspended solids, silt, or color.
Two of the equations are based on the Trophic State Index (TSI) developed
by Carlson (1977). This system, used by many States for classification purposes,
is essentially a rescaling of phosphorus, chlorophyll-a, and transparency
4-13
-------
measurements in units that are consistent with northern lake behavior (Fig.4-4).
The index provides a common frame of reference for comparing these measure-
ments. The scale is defined so that a decrease of index units corresponds to a
doubling of transparency.
PHYSICAL

APPEARANCE

>10% RISK
"DEFINITE ALGAE"

"HIGH ALGAE"

"SEVERE SCUMS-
RECREATION

POTENTIAL

>10% RISK
"MINOR AESTHETIC PROB"-

"SWIMMING IMPAIRED"

"NO SWIMMING"
OLIGOTROPHIC MESOTROPHIC EUTROPHIC HYPEREUTROPHIC

20 25 30 35 40 45 50 55 60 65 70 75 80
TROPHIC STATE
INDEX
TRANSPARENCY
(METERS)
CHLOROPHYLL-A
(PPB)
TOTAL
PHOSPHORUS (PPB)
15 1087654 3 215 1
05 0.3
0.5 1 2 3 4 5 7 10 15 20 30 40 60 80 100 150
5 7 10 15 20 25 30 40 50 60 80 100 150
Figure 4-4. - Carlson's Trophic State Index related to perceived nuisance conditions
(Heiskary and Walker, 1987). Length of arrows indicate range over which a greater than 10
percent probability exists that users will perceive a problem.
Carlson's index can be used to predict values of one variable from measure-
ments of another. For example, a lake with a measured mean transparency of
6.6 feet (2 meters) would have a TSI of 50. Based on the scales in Figure 4-4, a
mean chlorophyll-a of 7 ppb and a mean total phosphorus concentration of 23
ppb would also be expected for this lake. These predictions are approximate,
however (good roughly to within a factor of two, assuming that the lake under
study is typical of other northern lakes).
Various factors influence relationships among phosphorus, chlorophyll-a, and
transparency (Fig.4-1). Carlson's equations reflect relatively high chlorophyll-a
and transparency responses found in northern, natural lakes. Turbid, rapidly
flushed impoundments tend to have lower responses and less sensitivity to
phosphorus loading.
Heiskary and Walker (1987) describe a methodology for relating lake "trophic
state," as measured by phosphorus, chlorophyll-a, or transparency, to user-per-
ceived impairment in aesthetic qualities and recreation potential. The arrows in
Figure 4-4 indicate measurement ranges in which the risk of perceived nuisance
conditions (for example, "Swimming Impaired" or "High Algae") exceeds 10 per-
cent, based on surveys of Minnesota Lakes. These ratings may vary regionally.
Figure 4-5 provides additional perspectives on the relationship between im-
poundment phosphorus concentrations and eutrophication responses, as
measured by mean chlorophyll-a and transparency. The figure is based on
cross-tabulations of median total phosphorus, mean chlorophyll-a, and mean
4-14
-------
EPA National Eutrophication Survey
894 U.S. Lakes and Reservoirs
Probability Chlorophyll-A
1.0
Transparency
10 25 40 60 120>120 10 25 40 60 120>120

Total phosphorus interval maximum (PPB)
Trophic State

Oligotrophic
tvivi'3 Mesotrophic
\ZZZZ1 Eutrophic
•• Hypereutrophic
CHL-A
(PPB)

<4
4-10
10-25
>25
Transparency
(Meters)

>4
2-4
1-2
Figure 4-5.-Responses of mean chlorophyll-a and transparency to phosphorus.
transparency values from 894 U.S. lakes and reservoirs (U.S. Environ. Prot.
Agency, 1978). Phosphorus values are classified into six intervals (0-10, 10-25,
25-40, 40-60, 60-120, 120 ppb), and the probabilities of encountering mean
chlorophyll-a and transparency levels in Oligotrophic, mesotrophic, eutrophic,
and hypereutrophic ranges have been calculated for each phosphorus interval.
For example, if phosphorus is in the 25-40 ppb range, the probability of en-
countering a mean chlorophyll-a in the eutrophic range (10 ppb) is about .4, or
40 percent, and the probability of encountering a mean transparency less than
6.6 feet (2 meters) is about .75, or 75 percent. Variations in the response factors
such as depth, flushing rate, or turbidity (see Fig. 4-1) contribute to the distribu-
tion of chlorophyll-a and transparency that can be expected for a given phos-
phorus load.
Flushing rate: The rate at
which water enters and
leaves a lake relative to lake
volume, usually expressed
as time needed to replace
the lake volume with inflow-
ing water.
4-15
-------
Tracking Restoration Efforts
Figure 4-6 illustrates a type of "phosphorus loading diagram" often used to
depict modeling results (Vollenweider,1976). This diagram is developed by solv-
ing the equation for phosphorus concentrations from the Secchi depth of inflow-
ing waters and the hydraulic residence time (Equation 1 in Table 4-2.) The dotted
lines (representing phosphorus concentrations of 10, 25, and 60 ppb) are not
sharp boundaries of lake condition, but roughly delineate trophic state
categories based on average phosphorus concentrations. Corresponding
chlorophyll-a and transparency probabilities can be derived from Figure 4-5. The
object of the game is to move the lake away from the "HYPEREUTROPHIC"
(northeast) corner and toward the "OLIGOTROPHIC" (southeast) corner in
Figure 4-6, usually by reducing watershed point or nonpoint sources and
decreasing the average inflow phosphorus concentration (y-axis).

sr
Q.
O

O
o
in
ISPHORU!
u
0.
_j
i—
O
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o
U.
Z

IUUU

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i
O
a
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1 1

ONONDAGA
j*"
• ^^
LILLINONAH ^. "1
****\ —• -" WASHINGTON
P = 60 _--T-T"" t IJ ^"
LONG T • I ^
KEZAR SHAGAWA .,. •*] **\
„, • — "~ WAHNBACH *
P-25 — — "" "" ' 1 MOREY **
---"""" f { H „>-""
•-•
P = 10 — """"""
~" ^\
N.
x PREDICTED LAKE PHOSPHORUS (PPB)

I |
HYPER-EUTROPHIC
^ '
**
^
^^
^^ .
EUTROPHIC^ *• '

'MESOTROPHIC^ '
**
+

OLIGOTROPHIC

I
.01
.1 1 10
HYDRAULIC RESIDENCE TIME (YEARS)

LAKE VOLUME / OUTFLOW
100
Figure 4-6.-Restoration efforts tracked on Vollenweider's (1976) phosphorus loading dia-
gram.

The paths of eight documented restoration efforts are also plotted in Figure
4-6, based upon data summarized in Table 4-3. These case studies provide a
context for illustrating important modeling concepts. Figure 4-7 plots measured
mean phosphorus, chlorophyll-a, and transparency for each lake and time
period. These are compared with predicted values derived from the models in
Table 4-2. The predictions are driven by the inflow concentrations and hydraulic
residence times listed in Table 4-3. These comparisons illustrate model
capabilities to predict lake conditions before and after each restoration activity.
Figure 4-8 summarizes measured phosphorus budget information (inflow, in-
flow-lake, and lake concentrations) for each case and time period. The dif-
ference between the inflow and lake concentrations approximately reflects the
net influence of bottom sediments as a phosphorus sink (positive) or source
(negative) during each time period.
Each of the following sections discusses a particular case study.
4-16
-------
Table 4-3.—
in Chapter 4. These data were used to plot the progress of restoration efforts on the Vo.lenweider curve shown

LOCATION
IMPOUNDMENT TYPE
Lake Washington
Washington1
Natural Lake
Onondaga Lake
New York2
Natural Lake
Long Lake
Washington3
Reservoir
Shagawa Lake
Minnesota4
Natural Lake
Kezar Lake
New Hampshire5
Natural Lake
Lake Morey
Vermont6
Natural Lake
Wahnbach Reservoir
West Germany7
Reservoir
LakeLillmonah
Connecticut8
Reservoir
Sources ' Edmonson and Lehman (1981)
? Devan and EMler (1983) Walk.
1 Soltero and Nichols (1984)
4 Larsen and Malueg (1980)
DURATION ANDTYPE OF
RESTORATION ACTIVITY
1963-68 Point Source Diversion
1971 Detergent Ban & Sewer Repairs
1979-81 Point Source Treatment
1978 Point Source Treatment
1973 Point Source Treatment
1970 Point Source Treatment
1981 Point Source Diversion
1984 Hypolimnetic Alum Treatment
1986 Hypolimnetic Alum Treatment
1977 River Inflow Treatment
1 977 Point Source Treatment
5 Connor and Smith (1983 1986)

" Jones and Lee (1981)

OBSERVED WATER QUALITY RESPONSES HYDRAULIC MEAN
YEARS
1957
1963
1978
1970
1974
1985
1972-77
1978-82
1971-72
1974-78
1970
1981
1985
1981
1986
1 969-70
1978-79
1976
1977
Connor and Martin
am (1985) Smeltze

INFLOW P
(PPB)
94
155
48
3667
509
224
85
22
79
20
95
24
24
35
35
73
21
119
136
(1986)
r (1987)

LAKEP
(PPB)
26
62
19
2310
382
143
71
18
55
35
70
30
16
30
12
25
8
65
68

CHL-A
(PPB)
13
35
3
45
43
15
8
28
26
32
18
5
10
3
18
5
35
33

SECCHI RES. TIME DEPTH
(METERS) (YEARS) (FEET)
22 284 1080
1 0
64
21 0 28 39 4
1 2
0.9
019 47 9
19 070 187
24
10 0 13 92
1 4
30
44 1 93 27 6
60
30 1 70 59 0
60
1.1 008 390
1.6 014

SURFACE
AREA
21634
2889
5136
2272
180
543
558
1899

-------
a.
O
DC
O
120

too

20
[| I
. I. II
WASHINGTON ONONDAGAJ5 LONG SHAGAWA KEZAB MOREY WAHNBACH LILLINONAH

104 467 490 ^^_
Jl

H Ik, •,, K. I
WASHINGTON ONONDAGA/5 LONG SHAGAWA KEZAR MOREY WAHNBACH LILLINONAH
n
WASHINGTON ONONDAGA/5 LONG SHAGAWA KEZAR MOREY WAHNBACH LILLINONAH

I} OBSERVED RESPONSE | | PREDICTED RESPONSE
Figure 4-7.- Observed and predicted responses to restoration efforts.
Lake Washington, Washington: "You

Should Be So Lucky!"
Between 1957 and 1963, eutrophication progressed with increasing sewage
loadings from Metropolitan Seattle. Between 1963 and 1968, sewage discharges
were diverted out of the lake basin, reducing the total phosphorus loading to the
lake by 69 percent, relative to 1963. Observed and predicted conditions in 1978
reflect dramatic improvements in water quality that followed within a year or two
after the sewage diversion. Observed phosphorus concentrations agree well
with model predictions for each time period. Decreases in chlorophyll and in-
creases in transparency were somewhat more dramatic than predicted by the
models. Lake Washington is perhaps the most successful and fully documented
lake restoration project to date.

Onondaga Lake, New York: "Far Out. 93

Percent Is Not Enough."

Onondaga received primary treated sewage from Syracuse for many years. Bet-
ween 1970 and 1985, phosphorus loadings were reduced by over 93 percent as
a result of a phosphorus detergent ban, combined sewer repairs, and tertiary
treatment for phosphorus removal. Lake phosphorus levels responded in
proportion to loading reductions and in agreement with model predictions (Fig.
4-7). No significant improvements in chlorophyll-a or transparency were
achieved, however.
4-18
-------
The lack of algal response reflects the fact that pre- and postrestoration phos-
phorus levels were extremely high (exceeding 100 ppb; note the scale factor of 5
for this lake in Figs.4-7 and 4-8). Phosphorus usually does not limit algal growth
in this concentration range, particularly in deeper lakes. The chlorophyll model
(Equation 2 in Table 4-2) does not apply and substantially overpredicts algal
concentrations. Despite the substantial loading reductions as of 1985, Onon-
daga remained well within the hypereutrophic region of Figure 4-6 and on the flat
portion of the chlorophyll response curve shown in Figure 4-1.
8
Washington Onondaga/5 Long Shagawa Kezar Morey Wahnbach Lillmonah
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Washington Onondaga/5 Long Shagawa Kezar iVorey Wahnbach Lillmonah
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Washington Onondaga/5 Long Shagawa Kezar Morey Wahnbach Lillmonah

Figure 4-8.-Observed responses of phosphorus budget components to restoration efforts.

Onondaga illustrates the fact that some lakes subject to point-source phos-
phorus discharges may be susceptible to nuisance algal growths, even with ter-
tiary treatment to remove phosphorus. Although chlorophyll and transparency
did not respond, the disappearance of severe blue-green algal blooms following
the loading reductions was a significant water quality improvement.
Why didn't Onondaga Lake respond like Lake Washington? It started off in
much worse shape (Fig. 4-6). Onondaga has much shorter hydraulic residence
time (.28 versus 2.8 years) and, therefore, less opportunity for phosphorus
sedimentation. The loading plot (Fig. 4-6) essentially captures the relative
responses of these two lakes to restoration efforts.
4-19
-------
Long Lake, Washington: "What's This?

Reservoir Restoration?"

Beginning in 1978, tertiary treatment of sewage from Spokane reduced the
average seasonal phosphorus loading to this 22-mile-long reservoir on the
Spokane River by 74 percent. This impoundment has a relatively short hydraulic
residence time (.19 years, or 70 days). Accordingly, the inflow and reservoir
phosphorus concentrations are similar, and the sedimentation term is relatively
small (Fig. 4-8). Reservoir phosphorus levels responded roughly in proportion to
the loading. Mean chlorophyll-a concentrations were reduced by 45 percent and
were apparently less sensitive to the phosphorus loading reductions than
predicted by Equation 2 in Table 4-2. Northern lake models (such as Equation 2)
tend to overestimate chlorophyll-a sensitivity to phosphorus in some reservoirs
because of effects of algal growth limitation by flushing and light (Walker,
1982,1985).
Shagawa Lake, Minnesota: "The Little

Lake That Couldn't."

During 1973, external phosphorus loadings to this northern Minnesota lake were
reduced by 75 percent via point source treatment. Although average lake phos-
phorus levels during ice-free seasons were reduced by 35 percent, mean
chlorophyll-a and transparency did not respond according to model predictions
(Fig. 4-7). The lack of response has been attributed to phosphorus releases from
bottom sediments. These releases reflect historical loadings and the high sus-
ceptibility of this relatively shallow lake to hypolimnetic oxygen depletion and
wind mixing. The fact that lake phosphorus exceeded the inflow concentration
during the postrestoration period (Fig. 4-8) is indicative of sediment phosphorus
release.
Despite the fact that the phosphorus loading diagram (Fig. 4-6) places
Shagawa Lake at the oligo-mesotrophic boundary following load reductions,
mean chlorophyll-a concentrations remained in the hypereutrophic range during
the first few years following loading reductions. Over time, the rate of phos-
phorus release from bottom sediments may eventually decrease and permit the
lake to respond to the change in loading. This case points out the fact that load-
ing models of the type demonstrated here do not account for unusually high
sediment phosphorus release rates, which may defer lake responses to changes
in external loading.
Kezar Lake, New Hampshire: "The Little
Lake That Could (With a Little Help)," Or
"Shagawa Revisited ..."
This shallow, rapidly flushed lake was subject to a municipal sewage discharge
and in hypereutrophic condition for many years. Following installation of phos-
phorus removal facilities in 1970 and, eventually, complete elimination of the dis-
charge in early 1981, the external loading was reduced by about 75 percent. Like
Shagawa, the lake phosphorus concentration exceeded average inflow con-
centration during the initial period following loading reduction (Fig. 4-8). Kezar
4-20
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Lake (maximum depth = 27 feet) was thermally stratified in 1981. Significant ac-
cumulations of phosphorus released from thick, phosphorus-rich bottom sedi-
ments accompanied depletion of oxygen from the hypolimnion. Surface algal
blooms (chlorophyll-a = 60 ppb) were experienced during August 1981 and
were apparently triggered by escape of hypolimnetic phosphorus into the mixed
layer.
Because of sediment phosphorus releases, responses of lake phosphorus,
chlorophyll-a, and transparency to the 1981 sewage diversion were less
dramatic than predicted by the models (Fig. 4-7). In 1984, a hypolimnetic alum
treatment was conducted to address the sediment nutrient release problem.
Monitoring data from 1985 indicate that phosphorus, chlorophyll-a, and
transparency levels responded in agreement with model predictions following
the alum treatment. This case illustrates use of both watershed (point source
control) and in-lake restoration (alum treatment) techniques to deal with a lake
problem. Decreases in transparency following 1985 indicate that the book is not
yet closed on Kezar Lake, however.
Lake Morey, Vermont: "Strange Mud..."

Morey is a resort lake sheltered in the mountains of eastern Vermont. Aside from
the shoreline, the watershed is largely undeveloped. From the late 1970's to
1985, severe algal blooms and user complaints were experienced at increasing
frequency. Summer mean chlorophylls concentrations ranged from 8 to 30
ppb, transparencies ranged from 2 to 5 meters, and spring phosphorus con-
centrations ranged from 17 to 48 ppb. These variations in water quality could not
be explained by changes in land use, other watershed factors, or climate. Peak
algal concentrations were usually found in the metalimnion and were supplied
by phosphorus released from bottom sediments during periods of summer and
winter anoxia. The hypolimnion was relatively thin (mean depth = 7 feet) and
covered approximately 59 percent of the lake surface area. Bottom waters lost
their dissolved oxygen early in June and remained anaerobic through fall over-
turn.
A 2-year intensive study indicated that large quantities of phosphorus were
stored in the lake water column and sediments. At peak stratification in August
1981, for example, the total mass of phosphorus in the water column was about
five times the annual phosphorus loading from the watershed. Phosphorus
balance calculations (see Table 4-1) indicated that the lake inflow and outflow
concentrations were approximately equal, despite the relatively long hydraulic
residence time of 1.93 years. Equation 1 (Table 4-2) predicts that a lake with this
residence time should trap 58 percent of the influent phosphorus. Study results
indicated that Lake Morey was particularly susceptible to phosphorus recycling
from bottom sediments because of its shape (broad, thin hypolimnion suscep-
tible to rapid oxygen depletion) and iron-poor sediments (Stauffer,1981).
Model predictions for the Lake Morey prerestoration period were substantial-
ly below observed values of phosphorus and chlorophyll-a (Fig. 4-7). This
reflects the fact that phosphorus retention capacity was unusually low. Ob-
served transparency was higher than predicted, however, because of the ten-
dency for algae to concentrate in the metalimnion, below the mixed layer where
transparencies were measured.
Because the phosphorus budget indicated that the Morey's problems were
primarily related to internal recycling and not to watershed loadings, a hypolim-
netic alum treatment was conducted during early summer of 1986. The treat-
ment reduced average phosphorus and chlorophyll-a concentrations during the
period following treatment down to levels that were consistent with model
4-21
-------
predictions. Despite no significant changes in external loadings, the alum treat-
ment apparently restored Lake Morey to a mesotrophic status, consistent with
its position on the phosphorus loading diagram (Fig. 4-6).
The longevity of the treatment remains to be evaluated through future
monitoring. This is an example of how phosphorus budgets can be used to diag-
nose lake problems, regardless of whether or not the solutions involve reduc-
tions in external loading. Sewering of shoreline areas (a restoration activity
previously proposed and on the drawing boards for Lake Morey) would have
had little impact.
Wahnbach Reservoir, Germany: "When

All Else Fails ..."

Wahnbach Reservoir, a water supply for Bonn, Germany, was subject to high
phosphorus loadings from agricultural runoff and municipal point sources during
the period prior to 1977. The resulting severe blooms of blue-green algae that
developed in the reservoir caused major problems for the water supply. For
various reasons, the loadings from the watershed were largely uncontrollable. In
response to this problem, a detention basin and treatment plant were con-
structed at the major inflow to the reservoir in 1977. The treatment plant was
designed to remove more than 95 percent of the phosphorus inflow via sedimen-
tation, precipitation, flocculation with iron chloride, and direct filtration. Opera-
tion of this plant reduced the average inflow phosphorus concentration to the
entire reservoir by about 71 percent.
As illustrated in Figures 4-6 and 4-7, the inflow treatment restored Wahnbach
Reservoir from eutrophic to oligotrophic status during 1978-1979. Observed and
predicted lake phosphorus concentration dropped below 10 ppb. Chlorophyll-a
concentrations are consistently overestimated by the model, although the rela-
tive reduction in chlorophyll-a is correctly predicted. This relatively extreme and
costly restoration measure was justified in relation to the severe impacts of
eutrophication on drinking water quality and water treatment economics.
Lake Lillinonah, Connecticut: "You Can't

Fool Mother Nature ..."

Data from this 10-mile impoundment on the Housatonic River in Connecticut il-
lustrate the sensitivity of some reservoirs to hydrologic fluctuations. During 1977,
phosphorus removal was initiated at a municipal point source above the reser-
voir. This program reduced phosphorus loading from the point source by 51 per-
cent and reduced total loading to the reservoir by 8 percent during 1977.
Compared to the case studies discussed above, this loading reduction was
relatively small, and a major change in reservoir water quality would not be
anticipated. In fact, observed and predicted phosphorus and chlorophyll-a con-
centrations were slightly higher during 1977 (Fig. 4-7). The concentrations in-
creased primarily because the flow through the reservoir decreased by about 43
percent during 1977. As indicated by Equation 1 (see Table 4-2), the average in-
flow concentration is the most important variable determining phosphorus
predictions, particularly in reservoirs with low hydraulic residence times. Inflow
concentration is determined from the ratio of loading to outflow. The inflow con-
centration increased by 14 percent in 1977 because the small decrease in load-
ing was more than offset by the decrease in flow.
4-22
-------
For both time periods, the models overestimate reservoir phosphorus and
chlorophyll-a concentrations and underestimate transparency. Apparently,
phosphorus sedimentation in the Lillinonah was somewhat greater than
predicted by Equation 1. This is not unusual for long and narrow reservoirs with
high inflow phosphorus concentrations (Walker, 1982,1985). The loading plot
(Fig. 4-6) correctly predicts a hypereutrophic status for the Lillinonah during
both monitoring years.
Monitoring over a longer time period that includes years with flows similar to
those experienced during 1976 would be required to track the response of the
reservoir to the phosphorus loading reduction. Because the loading reduction is
relatively small, impacts may be difficult to detect in the context of year-to-year
variations. More substantial reductions in upstream point or nonpoint loadings,
or both, would be required to restore the reservoir to a eutrophic or mesotrophic
level.
4-23
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CHAPTER 5
Managing the Watershed
-------
CHAPTER 5
MANAGING THE WATERSHED
Introduction
Lake condition can be greatly influenced by watershed drainage. Since this is
so, it should be possible to begin lake restoration outside the lake, on the land.
An entire body of land practices is aimed at exactly that result; these techniques
are called best management practices. The last half of this chapter deals explicit-
ly with commonly accepted best management practices. These practices
originated in the field of agriculture, mainly to prevent soil loss.
Another central concept that this chapter reemphasizes is that lake water
quality is critically linked to the quality of incoming water. This chapter begins
with a discussion of water entering the lake both from specific discharge outlets
(point sources) and from generalized (nonpoint) sources.
The importance of the lake and watershed relationship cannot be overem-
phasized. While this Manual often uses the term lake system, it may be useful to
keep in mind that the lake is a system within a larger system, the watershed. The
emphasis in this chapter is on management practices that are appropriate for
lake homeowners, lake associations or districts, and small lake communities.
The Lake-Watershed

Relationship
Muddy waters, decreased depth, rapid filling from silt, aquatic weeds, algal
blooms, and poor fishing are typical problems of many lakes. Very often, to find
the cause it is necessary to look away from the lake to the surrounding land.
As Chapters 2 and 3 pointed out, the watershed contributes both the water re-
quired to maintain a lake or stream and the majority of the pollutant loads that
enter the lake. Effective lake management programs, thus, must include water-
5-1
-------
5-2
shed management practices. Trying to solve lake problems without correcting
the source or cause of the problem is not only shortsighted, it rarely works.
Pollutant loads to the lake can be contributed from the watershed as either
point sources or nonpoint sources. Point sources arise from a definite or distinct
source such as a wastewater (sewage) treatment plant, industrial facility or
similar source that discharges through a pipe, conduit, or similar outlet. They are
relatively easy to identify by tracing the discharge back to a specific source.
Point sources were traditionally considered to be the primary sources of pollu-
tion to waterbodies. This is no longer true for most lakes. Harder-to-identify and
harder-to-control nonpoint sources are more likely to be the principal con-
tributors of nutrient and sediment loads.
Point sources are usually controlled through wastewater treatment facilities
and State and Federally regulated permits such as the National Pollutant Dis-
charge Elimination System (NPDES).
Nonpoint sources, by contrast, do not originate from a pipe or single source.
Silt, nutrients, organic matter, and other pollutant loads are distributed over a
relatively broad watershed area. When water runs over land surfaces and picks
up these materials, they have the potential to enter the lake. They may be carried
directly to the lake with runoff or travel via a tributary stream or groundwater sys-
tem before entering the lake. Water running off a lawn or driveway during a
heavy rain is a common sight - this is nonpoint source runoff. Although non-
point source loadings can occur anywhere in the watershed, some land uses
such as agriculture, construction, and city streets contribute higher nonpoint
pollutant loads than other land uses such as forests and other highly vegetated
areas.
It is not always easy to distinguish a point source from a nonpoint source. For
example, parking lot runoff is considered a nonpoint source, but the runoff typi-
cally enters the lake or stream through a drain pipe or culvert. In this chapter,
point sources will be defined as homes, factories, other industrial concerns, was-
tewater treatment plants, and similar structures that discharge wastewater
through a pipe. For regulatory purposes, wastes from homes on septic systems
are considered nonpoint sources. In this chapter we discuss home wastewaters
with point sources since the discharge is discrete and easily identifiable. Non-
point sources will include all other types of pollutant loadings to the lake or
stream including lawns, driveways, subdivision roads, construction sites,
agricultural areas, forests, and other widespread sources.
Point Sources
Wastewaters from industrial, municipal, and household sources can be highly
enriched in organic matter, bacteria, and nutrients. Wastewater pollutants can be
extremely harmful to lake water quality, even when toxics or pathogens are not
involved. For example, when incoming water is high in organic matter, the bac-
teria that decompose organic matter can consume the lake's dissolved oxygen
supply more quickly than it can be replenished. The danger of this is especially
strong in thermally stratified lakes, where hypolimnetic oxygen may be totally
depleted. These oxygen depletions can lead to fishkills, odors, and noxious con-
ditions.
As organic matter decomposes, it can also contribute additional nutrients to
the water. The purpose of wastewater treatment is to remove the majority of the
oxygen-demanding matter, bacteria, and nutrients.
Most wastewater treatment plants have low discharge rates. Over 75 percent
of all publicly owned treatment plants discharge less than 1 million gallons per
day (mgd). Sewage treatment ponds or lagoons - the most common type of
-------
wastewater treatment facilities - typically have discharge rates less than 1 mgd.
These low discharge rates, however, do not mean the nutrient or organic loads
from these systems have an insignificant effect on lakes and streams.
At just 10-50 ppb total phosphorus concentration in the water, some lakes
may develop algal blooms, murkiness, and other problems. The average total
phosphorus concentration of wastewater treatment plant discharges is about
100 to 500 times greater than this. In many streams, wastewater discharges may
dominate streamflow during the dry summer period when total flow is lower than
usual. Also, at the higher summertime water temperatures, water cannot hold as
much dissolved oxygen as it does during the cooler periods of the year.
The combination of high, oxygen-demanding organic loads and lower than
normal dissolved oxygen levels is stressful enough in itself. The problem is com-
pounded when these high-organic, low-oxygen conditions coincide with the
peak growing season for algae and macrophytes. The incoming nutrients will act
as a fertilizer, encouraging excessive algal and macrophyte growth, which will
place additional stress on the dissolved oxygen supply as these plants decom-
pose.
Natural areas such as wetlands around a lake have occasionally been used
for advanced wastewater treatment because they can function as a biological fil-
ter to remove silt, organic matter, and nutrients from an inflowing stream to the
lake and improve lake quality. Wetlands, however, can also contribute organic
matter and nutrients to lakes under some conditions. Nutrients released from
wetlands can fertilize algal growth and contribute to lake problems. Whether a
wetland serves as a source or filter for nutrients and organic matter is an area
that needs better understanding and study.
The Federal Clean Water Act established the National Pollutant Discharge
Elimination System to regulate the discharge of nutrients and organic matter
from wastewater treatment facilities and provides financial incentives and
authorizes punitive actions to encourage the improvement of these facilities.
These facilities are regulated by the State water pollution control agency or by
EPA. Information on permitted facilities discharging into a lake or into streams
entering a lake can be obtained by contacting the State water pollution control
agency. If a problem appears to exist with a local treatment plant discharge, this
agency or the State health department should be notified.
Wastewater Treatment

Choosing the Scale of the System
If point sources are the most important contributor of organic matter, bacteria,
and nutrients, good wastewater treatment will be critical to protecting the lake.
The better the system is at removing organic matter, bacteria, and nutrients, the
fewer algal blooms, aquatic weeds, and odors will occur in the lake. Regardless
of the treatment system, however, all treatment systems require proper design,
operation, and maintenance. These requirements vary among treatment sys-
tems, but no system can be installed and then ignored. Systems must be main-
tained.

Municipal Systems
Typical waste treatment systems for larger cities and municipalities include a
conventional sewer system leading to a treatment facility such as an activated
5-3
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sludge treatment system. Primary wastewater treatment uses screens and
sedimentation (settling) to remove the larger floating and settleable organic
solids. Organic matter dissolved in the wastewater can still exert considerable
oxygen demand, however, so secondary treatment is used to reduce this
oxygen demand before the wastewater is discharged into the lake or stream.
Secondary treatment uses biological and chemical processes to remove 80-95
percent of the organic matter in the wastewater. Primary and secondary treat-
ment, however, do not significantly reduce dissolved nutrient (nitrogen and
phosphorus) concentrations.
Total phosphorus concentrations in untreated domestic wastewater are
reduced about 4 percent by primary treatment and about 12 percent using
secondary treatment. Total nitrogen has a higher removal rate, about 40 percent
of the total nitrogen removal with primary treatment and about 58 percent
removal with secondary treatment. This means, however, that about half the total
nitrogen and almost all the total phosphorus stays in the wastewater after secon-
dary treatment.
Another level of treatment tertiary or advanced treatment is required to sig-
nificantly reduce nutrient concentrations in the wastewater. Several tertiary treat-
ment procedures are available and more are being studied, but this level of
treatment is relatively expensive so it has not been applied to the same extent as
secondary treatment.
The best procedure for handling wastewater discharges to a lake is to divert
discharges away from the lake, out of the watershed. Lake Washington, dis-
cussed at the end of this chapter, is a classic example of how lake quality can
improve following point-source diversion. Another approach that has been used
when diversion is not possible is dilution or flushing. This requires a relatively
large source or supply of high-quality (low in nutrients and organic matter) water
to dilute the wastewater discharge and increase the flushing through the lake
(Welch and Tomasek, 1980). These procedures have been used primarily
with municipal wastewater treatment plants.
Normally, conventional treatment systems are not the best alternative for
small communities and individual homeowners. Conventional treatment plants
include systems such as activated sludge, bio-filters, contact stabilization, se-
quencing batch reactors and land treatment, and large-scale lagoons. More
detailed information and fact sheets can be found in the EPA Innovative and Al-
ternative Technology Assessment Manual (EPA No. 430/9-78-009, published in
February 1980).
Conventional treatment plants generally are complicated mechanical sys-
tems. They typically use large amounts of energy and are costly for small com-
munities to build. In addition, they require skilled operators to run and maintain
them. Wastewater is collected in most conventional systems by gravity, but the
cost per household of gravity sewers is high in small communities and increases
greatly in rural areas or wherever the ground is hilly, rocky, or wet.

Small-Scale Systems

Several small-scale treatment plants and designs are available for a small city,
town, or village. Even smaller-scale treatment systems exist that are suitable for
the lake homeowner or lake association. The choices can range from individual
on-lot systems to larger onsite treatment and collection systems servicing
several homes or small communities (Table 5-1). Characteristics of these treat-
ment systems, including their status, application, reliability, limitations, cleaning,
and treatment side effects are described in more detail in Appendix C.
5-4
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Table 5-1.—Examples of small-scale treatment plants and designs

EXAMPLE REMARKS~
Septic Tank
2. Septic Tank Mound System
3. Septic Tank - Sand Filter
4. Faculative Lagoon
5. Oxidation Ditch
6. Trickling Filter
7. Overland Flow Treatment
A septic tank followed by a soil absorption bed is
the traditional onsite system for the treatment and
disposal of domestic wastewater from individual
households or establishments. The system consists
of a buried tank where wastewater is collected and
scum, grease, and settleable solids are removed by
gravity and a subsurface drainage system where
wastewater percolates into the soil.

Can be used as an alternative to the conventional
septic tank-soil absorption system in areas where
problem soil conditions preclude the use of subsur-
face trenches or seepage beds.

Surface discharge of septic tank effluent. Can be
used as an alternative to the conventional soil
absorption system in areas where subsurface
disposal contain an intermediate layer of sand as
filtering material and underdrains for carrying off the
filtered sewage.

An intermediate depth (3 to 8 feet) pond in which
the wastewater is stratified into three zones. These
zones consist of an anerobic bottom layer, and
aerobic surface layer, and an intermediate zone.

An activated sludge biological treatment process.
Typical oxidation ditch treatment systems consist of
a single or closed loop channel 4 to 6 feet deep,
with 45° sloping sidewalls. Some form of preliminary
treatment such as screening, comminution, or grit
removal normally precedes the process. After
pretreatment, the wastewater is aerated in the ditch
using mechanical aerators that are mounted across
the channel.

The process consists of a fixed bed of rock media
over which wastewater is applied for aerobic biolog-
ical treatment. Slimes form on the rocks and treat
the wastewater. The bed is dosed by a distributor
system, and the treated wastewater is collected by
an underdrain system.

Wastewater is applied by gravity flow to vegetated
soils that are slow to moderate in permeability and
is treated as it travels through the soil matrix by
filtration, adsorption, ion exchange, precipitation,
microbial action and also by plant uptake. An
underdrainage system serves to recover the
effluent, to control groundwater, or to minimize
trespass of wastewater onto adjoining property by
horizontal subsurface flow.
On-Lot Septic Systems
On-lot systems refer to individual home sewage-disposal systems. The most
common on-lot system is the septic tank and drain field (Fig. 5-1). The septic
tank provides primary treatment by trapping solids, oil, and grease that could
clog the drain field. The tank stores sludge (solids that settle to the bottom)
and scum, grease, and floating solids until they can be removed during regular
5-5
-------
Inspection
Building paper
/W-i^C^A-V^wJVjV-V*
;i /• i-ij i iiCp-rA v&
^ i j i i j i jlra^yr^v r>^

•Disposal field section
Septic tank cross section.
Figure 5-1.-Septic tank and drain field.
septic tank cleaning (every 2-4 years, depending on use). Solids and liquids in
the tank are partially decomposed by bacteria. The wastewater that remains
after solids are thus removed flows out of the septic tank and into the drain field
tiles where it seeps into the soil. The soil filters this partially treated sewage, and
bacteria associated with the wastewater allow decomposition to continue.
As the wastewater flows through the drain field, phosphorus can be reduced
by adsorption to soil particles, but nitrogen is primarily reduced by biological
processes. Bacterial decomposition in the drain field reduces the oxygen
demand of this wastewater before it enters the lake or groundwater.
Some bacteria also convert nitrogen as ammonia to nitrate in the drain field.
While this reduces oxygen demand in the water, nitrate tends to move with the
water, eventually entering the lake in the groundwater. Ammonia and nitrate are
fertilizers, and encourage algal growth.
Septic systems can be effective in removing organic matter, bacteria, and
nutrients if properly designed and maintained. They only work, however, if the
proper site conditions exist. Many lakeside lots are inappropriate for septic sys-
tems, and lake problems have conclusively been associated with septic system
failure. Conditions that prevent or interfere with proper septic system function in-
clude unsuitable soils, high water tables, steep slopes, and underdesign or im-
proper use. Many of these conditions occur around lakes and can make lakeside
lots unsuitable for septic systems.
Soil plays a key role in the septic system. Tightly bound and poorly drained
soil types (clays) are not effective filters. At the other extreme, gravel is also a
poor filter because the wastewater drains through it so rapidly that little treat-
ment takes place.
Treatment is also prevented when the soil is too wet. Septic systems depend
upon good contact between the wastewater and relatively dry soil particles so
that the soil can adsorb nutrients as the wastewater passes through the system.
Saturated soils cannot adsorb nutrients well. Soils that drain very slowly may be
chronically saturated and the system, therefore, inoperative much of the time. In
5-6
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a poorly drained soil, the wastewater is also likely to surface and run directly to
the lake. A streak of especially green grass growing over the drain field indicates
that wastewater nutrients are fertilizing the lawn on the way up. High
groundwater tables can also prevent treatment by periodically flooding the drain
system. Steep slopes cause either rapid flow-through or surfacing of was-
tewater.
Frequently a septic problem can be traced to improper use and subsequent
malfunction. These problems commonly arise from underdesign, that is, too
small a tank or an inadequate drain field. Other problems are caused by serving
more people than the system was designed for, using improper washing
products, following a poor septic tank maintenance schedule, and putting solids
in the system (garbage disposal). Every health department or environmental
agency will have a good reference on the functioning and design of septic sys-
tems. EPA also has a design manual for onsite wastewater treatment and dis-
posal systems that is available (U.S. Environ. Prot. Agency, 1980b).
Alternative on-lot wastewater treatment techniques such as mound systems
(Fig. 5-2) and sand filters (Fig. 5-3) are available that may be more suitable for
many lakeside properties. These systems use the septic tank for solids removal,
but not the typical soil drain field.
Figure 5-2.-Mound Systems.

The mound system is suitable for rocky or tightly bound soils or areas with a
high water table. Instead of a drain field, a mound is created with fill material. The
wastewater from a septic or aerobic tank is allowed to seep through the soil in
the mound, which provides the treatment (Fig. 5-2).
A sand filter system can also be used where soils are unsuitable for conven-
tional drain fields. A 2 to 3-foot bed of sand is installed in or above ground to fil-
ter wastewater as it is released from the septic tank. The filtered wastewater can
be disposed through the soil as in a conventional septic drain field (Fig. 5-3).
Septic tank

Recirculation tank
Chlorinator
(optional)
Stream
discharge
Figure 5-3.- Sand Filters.
5-7
-------
Mound and sand filter systems represent only minor modifications to the typi-
cal septic system. They do not require major construction or substantially in-
crease cost. However, effluent from these systems can still enter the lake if the
groundwater movement is toward the lake. For any on-lot system, very careful
attention must be paid to the conditions of the site, the suitability of the system
for treating the waste, and to providing proper maintenance of the system.
Holding tanks, with or without chemical treatment, can eliminate the dis-
charge problem. Because holding tanks must be pumped on a regular basis to
remove the wastewater, they are not as convenient as conventional systems, but
for cottages or homes that receive limited weekend use, they can be an effective
alternative to other treatment techniques and reduce local lake problems.
As with the septic tank/drain field system, soil characteristics, groundwater
tables, usage conditions, slope, and other factors can influence the selection,
design, and operation of alternative on-lot treatment methods. Local health or
water pollution control agencies can assist the property owner in evaluating
these conditions and selecting the appropriate treatment system. The important
point is that alternative treatment technology to conventional septic systems is
available and should be evaluated.
Community Treatment

Facilities
For communities where existing sewage treatment facilities are adequate and
available, the solution is simply to tie into the public sewer system. Conventional
sewers are usually by far the major capital cost item of a wastewater system.
However, alternative sewer system designs are available that are much cheaper
than conventional systems but can still be tied into the public sewer system.
These sewers are smaller in size and are installed at shallow depths. They have
no manholes and fewer joints, which reduces rain and groundwater intrusion
into the sewer, thus reducing the treatment plant capacity required to treat this
additional water.
Three general types of alternative sewer systems might be much better for
small communities or individual homeowners when a major municipal or
regional facility already exists and has available capacity. In the first type, small-
diameter gravity sewers carry septic tank effluent away from the home. The
pipes, which are usually plastic, can be small (4-inch diameter) and placed at
less slope than a conventional sewer. Operation and maintenance requirements
are low.
Pressure sewer systems - the second type - use a small pump at eacn
house to move wastewater under pressure through small diameter plastic pipes
to a treatment facility or a larger interceptor sewer (Fig. 5-4).
The third general type is a vacuum sewer system (Fig. 5-5) that draws
wastewater from each home through small collector pipes to a central collection
station by vacuum. Wastewater entry into the system is controlled by vacuum
valves at each home or at groups of homes. The vacuum collection station
houses a pump that then delivers the collected wastewater to either the treat-
ment facility or an interceptor sewer. Because of their limited ability to lift waste-
water, vacuum sewers are best suited to flat areas where gravity sewers would
be too expensive.
In many communities, however, small-scale treatment is the only feasible ap-
proach, but site conditions prohibit the use of on-lot systems. Where lot sizes or
soil conditions are not suitable for onsite systems, cluster systems can be used
5-8
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2"-12" Plastic
Pressure Main
•Dwelling
1"-2" Plastic
Service Piping
Ball or
Gate Valve
—A—,
Septic
Tank
Effluent Pump
Check Valve

'Pumping
Chamber
Figure 5-4.-Pressure sewer systems.
Vacuum
Pump
Sewage
Buffer
Volume
Interface
Valve
3"-6" Plastic
Vacuum Mains
Transport Pockets
To Treatment
Facility
Sewage
Pump
Figure 5-5.-Vacuum sewer system.

(Fig. 5-6). Here, wastewater is conveyed by small-diameter sewers to a neigh-
borhood drainfield, mound, or sand filter. Construction and operating costs for
onsite or cluster systems are usually low, and the systems can be very simple to
operate. The key to their success is an efficient organization to manage their
operation and maintenance.
Some treatment systems are particularly appropriate for small communities.
Among the simple and reliable centralized treatment systems that are well suited
to small community situations are ponds, lagoons, trickling filters (Fig. 5-7),
oxidation ditches and overland flow treatment (Fig. 5-8). These systems are
described in more detail in Appendix C including their advantages, disad-
vantages, maintenance, and cost. All of these well-established methods provide
standard or better levels of treatment. In general, they cost less to build and run
than the common method of treatment called activated sludge. They also use
less energy and are easier to operate and maintain. When a community is start-
ing to plan a wastewater project, it should select an engineer who has ex-
5-9
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CLUSTER SEPTIC SYSTEM
Figure 5-6.-Cluster sewer system.

perience with these small community technologies. If the ongoing project did
not consider these technologies, a reevaluation of alternatives might be in order.
Information on particular systems appropriate for small communities can be ob-
tained from local contractors specializing in wastewater treatment, the local or
State health departments, water pollution control agencies, or EPA. EPA has
several excellent publications available, including their Innovative and Alternative
Technology Assessment Manual (EPA No. 430/9-78-009).
Figure 5-7.-Trickling filter.
5-10
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EVAPOTRANSPIRATION

GRASS AND VEGETATIVE LITTER

ROUNDOFF COLLECTION

SHEET FLOW
Figure 5-8.-Overland flow system.
Water Conservation to

Reduce Lake Problems
With a lake nearby, conserving water might not seem critical. Reducing water
usage, however, also reduces wastewater discharges. Water saving devices
such as flow-reducing showerheads and water saving toilets (or just using less
water in the tank) can cut household wastewater flows by as much as 25 percent
(U.S. Environ. Prot. Agency, 1981). Table 5-2 lists several water conservation
procedures. These procedures were taken from a bulletin issued by the local
Arkansas Cooperative Extension Service (U.S. Dep. Agric. 1984). The Extension
Service offices in each county have more information on this and other topics
that may be of interest to the lake homeowner and manager. Most of these pro-
cedures are very simple, even obvious, but the water they conserve can permit
smaller wastewater treatment facilities if these procedures are followed in many
homes around the lake. Even if a smaller treatment facility is not possible, reduc-
ing water use can lower day-to-day operating costs for expenses such as treat-
ment chemicals and utilities.
Water conservation is particularly appropriate in cases where existing treat-
ment capacity is limited or near the maximum. If a community is connected to a
regional sewer system, conservation measures can be effective in reducing
treatment charges, which are usually based on the volume of sewage treated.
This volume, in most cases, is monitored through water meter readings, and the
treatment charge is prorated on a household water usage basis.
Water conservation, then, not only costs less in the long run but also reduces
the potential loading of organic matter and nutrients to the lake, partly as a result
of reduced wastewater discharges. More careful usage may also lower nonpoint
source loadings from activities such as watering lawns.
5-11
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Table 5-2.—Conscientious use of water can prevent excess run off and reduce
the volume of waste water treated, both of which help protect lake
water quality

WATER CONSERVATION TECHNIQUES
• Inspect the plumbing system for leaks.
• Install flow control devices in showers.
• Turn off all water during vacations or long
periods of absence.
• Check the frequency with which home
water softening equipment regenerates
and backwashes. It can use as much as
100 gallons of water each time it does this.
• Insulate hot water pipes to avoid having to
clear the "hot" line of cold water during use.
• Check all faucets, inside and out, for
drips. Make repairs promptly. These
problems get worse—never better.
• Reduce the volume of water in the toilet
flush tank with a quart plastic bottle filled
with water (bricks lose particles, which
can damage the valve).
• Never use the toilet as a trash basket for
facial tissues, etc. Each flush uses 5 to 7
gallons of water. Items carelessly thrown in
could clog the sewage disposal problems.
• Accumulate a full laundry load before
washing, or use a lower water level setting.
• Take showers instead of baths.
• Turn off shower water while soaping body,
lathering hair, and massaging scalp.
• Bottle and refrigerate water to avoid
running excess water from the lines to get
cold water for meals. Shake bottle before
serving to incorporate air in the water so
that it doesn't taste flat.
• To get warm water, turn hot water on first;
then add cold water as needed. This is
quicker this way and saves water, too.
• Wash only full loads of dishes. A dish-
washer uses about 9 to 13 gallons to
water per cycle.
• When washing dishes by hand, use one
pan of soapy water for washing and a
second pan of hot water for rinsing.
Rinsing in a pan requires less water than
rinsing under a running faucet.
• Use rinse water—"gray water"—saved
from bathing or clothes washing to water
indoor plants. Do not use soapy water on
indoor plants. It could damage them.
• Vegetables requiring more water should
be grouped together in the garden to
make maximum use of water applications.
• Mulch shrubs and other plants to retain
moisture in the soil longer.
Spread leaves, lawn clippings, chopped
bark or cobs, or plastic around the plants.
Mulching also controls weeds that com-
plete with garden plants for water.
Mulches should permit water to soak into
the soil.
• Try "trickle" or "drip" irrigation systems in
outdoor gardens. These methods use 25
to 50 percent less water than hose or
sprinkler methods. The tube for the trickle
system has many tiny holes to water
closely spaced plants. The drip system
tubing contains holes or openings at
strategic places for tomatoes and other
plants that are more widely spaced.
• Less frequent but heavier lawn watering
encourages a deeper root system to
withstand dry weather better.
• Plan landscaping and gardening to
minimize watering requirements.
•When building or remodeling, consider:
—Installing smaller than standard bath
tubs to save water.
—Locating the water heater near area
where hottest water is needed—usually
in the kitchen/laundry area.
5-12
How to Assess Potential

Sources
Consider the relative importance and contributions of point sources and non-
point sources to the lake. Preparing a water and nutrient budget as discussed in
Chapter 3 and described in Chapter 4 is an essential beginning.
The watershed to lake surface area ratio is also important. This ratio can indi-
cate whether point or nonpoint sources are likely to dominate water quality. This
ratio is quite simple to calculate: Lake area ratio equals the watershed area
divided by lake area (computed in acres). If the watershed is small, local point
-------
sources and septic tank drainage are probably quite important. As the water-
shed to lake surface ratio increases, these sources might still be important, but
nonpoint sources also must be considered.
Assessing Point and

Domestic Wastewater Sources
With an existing on-lot system, the first step is to contact the local or State health
department or water pollution control agency to determine whether the system
is operating satisfactorily. If it is, finding out how to maintain the system in good
condition is all that is necessary. If the system is not working well, however, cor-
recting the malfunction will be necessary. The agency that checked the system
can provide advice and referrals for further information and may even offer ser-
vices to correct treatment system problems.
When considering installing an on-lot system, the individual homeowner or
community should contact the local city or county agent and find out what or-
dinances may exist for minimum setbacks from the lake, mandatory wastewater
treatment, or other requirements.
If it is absolutely necessary for a community treatment system to discharge to
the lake, it is important to determine whether the additional phosphorus loading
will promote algal problems. Chapter 4 describes methods to evaluate this, but it
is strongly recommended that wastewaters not be discharged directly to a lake.
A community treatment system may already be discharging into the lake or
into a stream that enters the lake; however, information on whether it does and
whether it meets its permit requirements is available from the local or State water
pollution control agency. When a community system does discharge directly to
the lake or incoming stream, it is important to check the discharge area during
the summer for problems such as algal blooms, turbid water, or other condi-
tions. The permit for each treatment facility is periodically available for public
review and comment before being reissued. If it appears that problems are oc-
curring in the lake, the local water pollution control agency should be notified of
the potential problem.
Nonpoint Sources
The importance of nonpoint sources of pollution became apparent as municipal
and industrial point sources were controlled. In many cases, projected reduc-
tions in nutrients and improvements in water quality were not reached. Agencies
responsible for lakes and streams attempted to find out why. Point sources,
which had been perceived to contribute to the majority of water quality
problems, had masked nonpoint source pollution problems. Once point sources
were subjected to corrective actions, the importance of nonpoint sources be-
came apparent. Only by stepping away from the narrow viewpoint (that point
sources caused nearly all water quality problems) were water quality managers
able to see the lake and watershed as an integrated system being affected by
diverse sources of pollutants.
By approaching the management of lakes and streams from a broader
perspective, water managers and scientists found that in many systems non-
point sources were equal to or greater than point-source contributions and, in
general, nonpoint sources were major contributors of sediment organic matter
5-13
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and nutrients to a lake. Although the nutrient concentrations in runoff waters or
the amount of nutrients adsorbed to the sediments were not as great as the
nutrient concentrations in a point source, the total load (concentration times
flow) can be substantial and far exceed point-source contributions.
Cultural Sources of

Sediments, Organic Matter,

and Nutrients
Figure 5-9 illustrates a typical lakeside scene from the window of a lakeside
home. Many sources of nutrients and sediments to the lake are depicted:

• Flower and vegetable gardens - contribute nutrients, sediments, and
pesticides if not properly managed

• Septic tank systems - contribute nutrients and bacteria

• A well-manicured lawn - contribute nutrients (fertilizers) and herbicides
Although not illustrated, car maintenance can contribute nutrients to a lake
from wash water and oil slicks from improperly dumped motor oil. The very
presence of people on a lake conducting day-to-day activities is in part respon-
sible for nutrients and sediments that accumulate in the lake.
ROAD . •^•>>^*iiJ4:M
RUNOFF .
... . SHORELINE EROSION
FERTILIZERS &
PESTICIDES
5-14
Figure 5-9.-Watershed activities as seen from individual homesite.

These examples are of pollutants that occur off an individual lot. Even if the in-
dividual contribution is insignificant, the cumulative contribution from all the in-
dividual lots surrounding a lake could be significant. In addition, it is very
important that homeowners living near the lake exhibit concern for their own pol-
lution if they wish to convince others in the watershed to improve their habits.
-------
As explained earlier, nonpoint sources are likely to be important in large
watersheds. A common method to determine the relative importance of various
sources of nutrients and sediments to a lake is to determine the area of the
watershed in relation to the area of the lake. For example, if there are 100 acres
in the watershed and the surface area of the lake is 100 acres, then the water-
shed to lake surface area ratio is 1 to 1 (also represented as 1:1). In small water-
sheds (for example, a 1:1 ratio), the local sources of organic matter and
nutrients, such as septic systems and runoff from lawns and gardens carrying
nutrients, might represent the primary contributors of pollutants to the lake.
Referring back to Figure 5-9, additional sources were illustrated across the
lake. Construction activities can be significant sources of sediments, especially
during rainstorm events. Runoff from roads are additional sources of nutrients,
sediments, and heavy metals.
As the watershed to lake surface area ratio becomes larger, other sources of
pollutants such as agricultural runoff carrying animal wastes (organic matter),
soil, and nutrients become increasingly important. Urban runoff from streets,
storms, and rooftops will become significant sources of sediment, organics (oils
and greases), nutrients, and heavy metals to lakes. Silvicultural activities also will
become increasingly important as sources of sediments. In large watersheds,
the contribution from urban, silvicultural, and agricultural areas are generally
more significant than those from lakeshore homes.
What are Best Management

Practices?
Before a discussion is initiated on how to restore a lake, background on techni-
ques available to improve water quality must be developed.
The lake association or local residents have a number of options available to
improve the water quality of the lake. They range from picking up litter around
the lake to the implementation of best management practices (BMPs) in the
watershed. Best management practices have been developed for agricultural,
silvicultural, urban, and construction activities. Agricultural practices, for ex-
ample, have been developed for cropland, pastures, barnyard or manure
management, and pesticide control. Silvicultural practices have been developed
for activities such as road construction in timberlands, timber harvest techni-
ques, regenerating forest lands cut or killed by disease or fire, and the use of
pesticides. Urban practices have been designed to keep city streets and road-
sides clean, while construction practices were developed for erosion and runoff
control.
In general, these best management practices were not designed with water
quality protection as a goal, but rather to maintain productivity on the land,
reduce costs of pesticides and fertilizers, or prevent lawsuits because of mud
slides or flooding on neighboring properties. Regardless of their original intent,
many of these practices are useful in lake restoration projects.
Managers of lakes and streams focus on best management practices to con-
trol four primary, interactive processes: (1) erosion control, (2) runoff control, (3)
nutrient control, and (4) pesticide or toxic controls. These processes are highly
interactive because runoff control, for example, offers benefits for reducing sedi-
ments, nutrients, and pesticide contamination in lakes and streams. Control for
other factors, however, may still be necessary. Runoff control, for example, may
minimize water erosion, but wind erosion may account for 10-14 tons of soil loss
per acre every year from croplands in some of the Great Plains States.
5-15
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Table 5-3 lists various best management practices applied during different
land use activities. Definitions and explanations as to their effectiveness, capital
costs, longevity, confidence, adaptability, potential effects, and concurrent land
management practices can be found in Appendix D. In this analysis effective-
ness refers to how well a practice reduces sediments, organic matter, nitrogen,
phosphorus, and runoff. Capital costs refers to the costs that would be incurred
by the farmer, forester, contractor, or municipality to implement the best
management practice. Operational and maintenance costs refers to those costs
required to keep the best management practice working properly.
Table 5-3.—A list of Best Management Practices applied during different
land use activities.
BEST MANAGEMENT PRACTICES
AGRICULTURE
CONSTRUCTION
Conservation Tillage
Contour Farming
Contour Stripcropping
Integrated Pest Management
Range and Pasture Management
Crop Rotation
Terraces
Animal Waste Management
Fertilizer Management
Livestock Exclusion

URBAN
Porous Pavements
Flood Storage
Street Cleaning

SILVICULTURE
Ground Cover Maintenance
Road and Skid Trail Management
Riparian Zone Management
Pesticide/Herbicide Management
Nonvegetative Soil Stabilization
Disturbed Area Limits
Surface Roughening

MULTICATEGORY
Streamside Management Zones
Grassed Waterways
Interception or Diversion Practices
Streambank Stabilization
Detention/Sedimentation Basins
Vegetative Stabilization
Longevity is either short term or long term. For this discussion, short term
means the practice is good only for a year or season. Long-term practices are
those that last longer than 1 year. The terminology is not clear-cut because
some practices have to be applied every year but are considered to be long term
because the implementation of the practice is not designed to provide instant
results. An example is conservation tillage. In conservation tillage, plant residue
is left on the field after harvest. When a conservation tillage practice is initiated,
the farmer does not expect to have significant results in the first year but will be
able to maintain or protect the productivity of the land over the long haul. The
benefits the lake receives are also not noticeable in the first year but will be per-
ceived over a period of years.
Confidence is based upon how consistently a best management practice
works in reducing a problem. One might have little confidence in a best manage-
ment practice that works only on a hit or miss basis. In many cases, the scientific
evidence is not yet available to assess the confidence associated with a given
best management practice.
When a best management practice can be used in a variety of geographic
areas and situations, it is considered to be adaptable. For example, the adap-
tability of conservation tillage is ranked as good instead of excellent because it is
limited in Northern States that experience late, cool springs or in heavy, poorly
drained soils, even though it can be applied in a variety of geographic areas.
5-16
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Potential treatment side effects refers to the possibility of causing another
problem by treating the problem of immediate interest. For example, even
though the use of conservation tillage can reduce soil erosion, runoff, and
nutrient losses, the increased use of chemicals may lead to groundwater pollu-
tion.
When a best management practice is applied, there is generally a supporting
best management practice that will increase the effectiveness of the primary
practice. In the case of implementing a conservation tillage program, a fertilizer
management and integrated pesticide management program should also be in-
itiated as a supporting practice.
Lake Restoration Begins in

the Watershed
The best place for any lake association to start a restoration project is in its own
backyard. There are a number of actions individual lake homeowners can in-
itiate, for example:

• Collecting the litter tossed in yards and along the roads.

• Leaving the grass or shrubs up to the lakeshore or along roads uncut to
act as a buffer strip to reduce nutrient and sediment loads to a lake.

• Modifying agricultural best management practices for flower or vegetable
gardens. Although agricultural best management practices were
designed for large fields (40-1,000 acres), they can be scaled to
backyard plots.

• Adopting a form of conservation tillage, integrated pest management,
and fertilizer management. Leaving after-harvest vegetable crop residue
in gardens can minimize local sources of nutrients, organic matter and
sediments.

During the growing season, integrated pest management and fertilizer
management may be appropriate. Integrated pest management is a practice
that considers the best timing dosage and handling of pesticides for maximum
effectiveness with minimal waste or overuse. Other considerations include
selecting resistant vegetable varieties, optimizing vegetable/flower planting time
rotating plants, and using biological controls. Local Extension agents are good
reference sources to determine resistant plant variety locally suitable.
Fertilizer management considers the proper time to spread a fertilizer and the
proper amount to optimize plant growth with minimal impact on the lake. Fer-
tilizer and pesticide management actually save money because the proper
amount of fertilizer or pesticide is applied when it does the most good This
reduces both the amount and the number of times fertilizers and pesticides need
to be used. Again the local Extension agent can be of assistance In addition
Soil Conservation Service (SCS) personnel can provide information on locally
dominant soil types and assist in determining the appropriate amount and type
of fertilizer.
Once lake homeowners have initiated best management practices on their
own lots, it is time to start moving outward into the watershed. By working
together, lakeshore property owners can accomplish a number of small projects
that will help reduce nutrient and sediment loads to a lake. For example
eliminating curbs and gutters allows the road runoff to proceed over grassed
areas that will filter sediments and utilize the nutrients. Best management
5-17
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practices that could be applied include vegetative stabilization, grassed water-
ways, streamside management zones, streambank stabilization, and deten-
tion/sedimentation basins. These practices, described in Appendix D, all help
reduce the input of organic matter, silt, and nutrients to the lake.
In a streamside management zone, the natural vegetation is maintained be-
side the stream. If vegetation has been removed, it should be replanted. Planting
erosion-resistant grasses in natural or constructed drainage channels to make a
grassed waterway is another practice that lake associations might encourage. In
concept, vegetative stabilization is similar to grassed waterways and streamside
management zones, using erosion-resistant plants or plants that are known to
stabilize soil in erosion-sensitive areas such as steep slopes. If a stream entering
the lake has currents that are eroding banks, however, vegetation may not suf-
fice. Another project that a group might initiate is streambank stabilization where
a layer of carefully graded rocks (rip rap) is placed over the area of erosion. In
some cases, a blanket of nonvegetative fiber or layer of sand must be placed
before rip rapping. The area may also require detention/sedimentation basins
designed to slow runoff for a short time and to trap heavier sediment particles.
Additional information is available from the SCS and local drainage improvement
districts or land improvement contractors.
With a large watershed, the tasks facing the lake association become more
complex. Now the organization has to work with property owners who may not
live near the lake, private contractors, municipalities (such as zoning commis-
sions), and county planning agencies that may or may not be concerned about
the lake. In some cases local ordinances or zoning regulations might need to be
passed to regulate construction or other land use activities. The lake organiza-
tion may require that construction areas implement best management practices
such as nonvegetative soil stabilization, disturbed area limits, and surface
roughening.
Nonvegetative soil stabilization includes actions such as covering disturbed
areas with mulches, nettings, crushed stone, chemical binders, and blankets or
mats. This best management practice is a temporary measure that should be
used until a long-term cover is developed.
The best management practice known as disturbed area limits is nothing
more than a common sense approach to minimize the area disturbed by the
construction activity. If vegetation is removed, surface roughening can be ap-
plied on the exposed soil. Conventional construction equipment is used to
scarify, or groove, the soil along the contour of a slope. In practice, the grooves
spread the runoff horizontally and increase the time for water to soak into the
ground.
As the watershed to lake surface area becomes larger, the task of watershed
management becomes more expensive and more complex. It is important to
realize that not all areas of the watershed are equally important and to identify
those that are critical contributing areas so that available funds can be op-
timized. A critical area is one that contributes excessive amounts of soil and
nutrients to the lake or a stream course that enters the lake. How to delineate
these areas is discussed in Chapter 3 on Problem Identification. An educational
program on watershed management should also be considered. The only
reason some individuals contribute nonpoint source loads to lakes is their lack of
awareness of the impact of their actions. Educational approaches are critical in
successfully implementing a management plan (see Chapter 8).
Any one or all of the best management practices listed in Table 5-3 and in Ap-
pendix D may be applicable in the lake's watershed. The best approach is to tar-
get those areas that are concentrating the most significant sediment, organics,
or nutrient loads. This may entail starting a modest monitoring program as dis-
cussed in Chapter 8.
5-18
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The practices just discussed addressed the actions a lake association can
take around the lake. To maintain these practices and protect lake quality might
require the use of regulations, zoning, or ordinances. These regulatory proce-
dures can be effective tools for lake and watershed management and are dis-
cussed in Chapter 9.
Guidelines and
Considerations
Controlling nonpoint sources and identifying the most feasible alternatives can
be considered as a seven-step process. These steps include:
Step 1. Form a lake association or lake district: Several voices have more
strength than one. The North American Lake Management Society is an or-
ganization that can help organize a lake association. Some States have already
formed a Federation or Congress of Lake Associations. Members from other
lake associations can be a good source of information.
Step 2. Identify potential problem sources: Start with the lake homeowners
and then move around the lake and out into the watershed. This is the first step
to define the extent of the problem. Refer to Chapter 3.
Step 3. Identify Critical Areas: Critical areas are those areas that are con-
tributing a majority of the sediments and nutrients to the lake. Not all areas
necessarily contribute equally to lake problems. Refer to Chapter 3. Part of iden-
tifying a critical area is common sense. If a farmer is plowing up to the edge of a
stream, a feedlot is located on a stream or lake, or a clearcut is located close to
a stream, those areas become potential candidates for critical areas. In many
cases, the lake association will not be able to directly correct watershed
problems created by agricultural, urban, or silvicultural activities. Ordinances or
local zoning regulations might be necessary (see Chapter 9).
Step 4. Initiate watershed management practices: Common best manage-
ment practices were explained earlier, and it was stated that they were initially
developed for purposes besides water quality improvement. The intent of this
document is to develop in lake associations and lake homeowners an apprecia-
tion of the relationship between the lake and the watershed. Generally no one
practice is adequate by itself, and many practices must be integrated.
Step 5. Determine allocation of resources: A lake association or lake dis-
trict will in all likelihood be limited by resources. The best place to start in any
watershed management program is in the association's own backyard. Many of
the best management practices considered for agricultural, urban, or silvicul-
tural activities are applicable in the lake homeowner's backyard on a reduced
basis. Buffer strips around the lake are just as applicable to a homeowner as to a
farmer, as are fertilizer management, pesticide management, conservation til-
lage, street cleaning, or nonvegetative soil stabilization. The association can
eliminate curbs and gutters and allow runoff from stormwater to filter through
buffer strips along roadways. A common sense approach is the key, and a lake
association will probably be more effective in the upper watershed if they correct
their own problems first.
Step 6. Investigate regulations and zoning: Consider regulations or zoning
time and space to resolve lake problems both of land use and lake users (see
Chapter 9). A lake problem is a limitation on a desired use. In some instances,
other lake uses and users are the problems. Some uses will not be compatible in
all lakes, so it is important to decide which lake uses have the greatest priority
5-19
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and manage to achieve these uses. Regulations can assist in achieving these
uses.
Step 7. Employ tools in combination: Consider an integrated program of
watershed management and in-lake restoration. To develop an effective lake
management plan, all the available tools should be considered, and the ap-
propriate ones incorporated in the plan. The next chapter discusses the third leg
of the lake management triangle-lake restorations.
Examples of Point and
Nonpoint Improvement
Projects
Lake Washington: Point-Source

Diversion

Lake Washington is considered to be a classic example of water quality improve-
ment with the diversion of sewage. In 1958 the public voted to divert sewage
from Lake Washington, but the first diversion did not take place until 1973, and it
took 5 more years to complete the system. With the first diversion, which
stopped about 28 percent of the effluent, the lake stopped deteriorating, and
during the 5-year diversion period the lake showed signs of recovery. Between
1967 and 1968 the change in water quality took place rapidly. Edmondson
(1972) reported that the content of phosphorus in the surface waters decreased
about a fourth of its maximum value, microscopic plants decreased, and
transparency increased (see Chapter 4).
Annabessacook Lake, Cobbossee Lake,

and Pleasant Pond: Point-Source
Diversion/Nonpoint Source Waste

Management/in-Lake Treatments
Annabessacook Lake is an example of a hit or miss approach to lake restoration.
For years, the lake was considered to be the most polluted lake in Maine. From
1964 to 1971 residents attempted to solve their algae problems with copper sul-
fate, but each year the effectiveness became shorter and resistant algae
predominated. In 1969 steps were taken to divert sewage from the lake. The
diversion resulted in an improvement, but algae growth continued to be a
nuisance. To accelerate recovery hypolimnetic aerators were installed, but there
was no positive response.
5-20
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After over 30 years of frustration in attempts to improve water quality in the
chain of lakes (Annabessacook Lake, Cobbossee Lake, and Pleasant Pond),
lakeshore property owners, local officials, and concerned citizens formed the
Cobbossee Watershed District, which was to serve as a quasi-governmental
agency similar to a school district or sewer authority. Through their taxing
authority, a Federal water quality management (208) planning grant, and the
Agricultural Stabilization and Conservation Service, they were able to conduct a
formal study of nonpoint sources of pollution to formulate a comprehensive res-
toration plan.
In Pleasant Pond, agriculture was found to be the dominant source of phos-
phorus nonpoint pollution and the second leading cause in Annabessacook and
Cobbossee Lakes. Lake sediments were the primary source in Annabessacook
Lake. After careful consideration, a two-pronged approach was taken. An
agricultural waste management program was undertaken in the watershed and a
nutrient inactivation was applied to the lake. The major agricultural activities in
the watershed were dairy and poultry farming, and it was a widespread practice
to spread manure on frozen ground and snow. Therefore, to implement a waste
management program, a storage capacity for 6 months of accumulated manure
was necessary.
By using animal waste management (storage during winter months) and alum
(aluminum sulfate) plus sodium aluminate to inactivate phosphorus, the total
phosphorus loads were reduced approximately 45 percent. From the lake users
viewpoint the improvement in water clarity has been a positive benefit (U.S.
Environ. Prot. Agency, 1980a).
East and West Twin Lakes: Septic Tank

Diversion

The results of septic tank diversion and alum treatment were part of a research
project (Cooke et al. 1978) funded by the U.S. Environmental Protection Agen-
cy. This study is included as an example because it demonstrates that septic
tanks can affect a lake even when sited in ideal soil.
Prior to septic tank diversion, fecal coliform levels ranged from too numerous
to count to 260 colony forming units/100 ml. The standard for fecal coliform
colony forming units is 200/100 ml, and levels above this limit resulted in the
lakes being closed to contact recreation. After diversion, fecal coliform levels
quickly reformed to near zero levels in groundwater, streams, and lakes. Al-
though the septic systems were sited in soils presumably ideal, Cooke et al.
(1978) found perched water tables in the leach field. They assumed the perched
water table was the result of organic material clogging the leach field and reduc-
ing permeability. This situation allowed nutrient-rich and fecal material to be
washed from the lawns to ditches and streams that entered the lakes.
A concurrent decrease in phosphorus concentrations was not observed be-
cause the lakes continued to receive untreated storm flow and runoff from
diverse nonpoint sources typical of eutrophic lakes. Cooke et al. (1978) con-
cluded that the diversion of septic tanks did prevent the situation from becoming
worse and potentially reaching a point where all recreation would have to cease.
5-21
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CHAPTER 6
Lake and Reservoir
Restoration and
Management
Techniques
-------
CHAPTER 6

LAKE AND RESERVOIR

RESTORATION AND

MANAGEMENT TECHNIQUES

Introduction

This chapter covers the major restoration and management techniques that are
used within lakes and reservoirs. Somewhat like prescriptions for treating lake
ailments, these techniques have benefits, side effects, and limitations. All have
demonstrated and proven value, but none is suitable for every lake, for an all-in-
clusive range of problems, or even for a specific problem under varying cir-
cumstances.
With that warning delivered, what can the reader expect to gain from this
chapter? Its threefold objective is to help the reader

• Understand the limits of lake and reservoir restoration and management
methods

• Ask the critical questions involved in choosing the most appropriate
procedure

• Become familiar with the various methods with regard to their basic
ecological principles, their mode of action, their effectiveness and
potential negative impacts, and - where known - their costs

The Principles of Restoration

The lake user needs to consider two important ideas regarding lake protection
and restoration before proceeding to study and select methods appropriate to
any particular lake or reservoir:
6-1
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First, in the long term, the condition of a waterbody is dictated primarily by the
quality and quantity of water entering it. While there can be qualifications to this,
including effects offish, sediment release of nutrients, and basin shape, it is clear
that nearly all restoration procedures will be overwhelmed by continued high in-
comes of silt, organic matter, and nutrients. Protection and watershed manage-
ment (see Chapter 5) are therefore paramount to restoration.
Second, lake restoration is, by definition, the use of ecologically sound prin-
ciples to attempt to bring about long-term improvement in lake or reservoir con-
dition (Cooke et al. 1986).
Restoration techniques can be divided into three general groups, based upon
the ecological principles behind them:
1. Control of plant growth through control of factors such as light or nutrients,
or substrate (sediments)
2. Improvement of conditions for certain organisms that are capable of con-
trolling excessive vegetation biologically
3. Removal of nuisance organisms or sediments
Lake restoration does not include symptomatic treatments such as an her-
bicide or algicide application, although these chemicals can form an important
part of a vegetation management program. Such programs are not restorative
because they do not treat the causes of excessive vegetation and therefore must
be frequently reapplied. Furthermore, some of them are associated with un-
desirable side effects.
Costs are a very important consideration, as well. The more management-
and symptom-oriented the technique, the greater the likelihood that the long-
term benefit-to-cost ratio will be poor. While a restoration-oriented technique
usually costs more at the outset, restoration lasts. It is hardly wise to consider a
restoration program that provides at least 10 years' worth of benefits to be "ex-
pensive" compared to a management "bargain" that has to be repurchased 10,
20, or 30 times in the same span without ever solving the real problem.
Some readers will be aware of products or procedures not mentioned here.
Ultimately, some of these could prove to be effective and have minimal un-
desirable side effects. As these techniques are thoroughly tested and proven to
be effective, they will be added to this chapter. Only techniques that have been
fully described in the open scientific literature are listed in this Manual. Lake
managers should always ask for scientific documentation regarding a proce-
dure or technique, especially one not described here, and should never
hesitate to discuss it with a lake restoration expert not financially involved in its
sale or installation.

Are Protection and Restoration

Possible?

Some eutrophic lakes and most reservoirs probably cannot be restored. Either
they cannot be protected or the users' expectations are not consistent with
achievable conditions. An estimation of the degree to which a waterbody can be
improved is one of the functions of the diagnostic/feasibility study (Chapter 3),
which answers questions relating to sources of nutrients, silt, and organic matter
loadings, and the present condition of the lake. For example, if the primary
source stream is of poor quality and it is not feasible or practical to improve it,
protection will be impossible. For another example, reducing nutrient loading
won't cure a weed problem if the nutrients already in the lake's sediments are
capable of sustaining it. A diagnostic/feasibility study will forewarn the lake
manager of these possibilities.
6-2
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Reservoirs are extremely difficult to protect and therefore to restore. As
described in Cooke et al. (1986) and Cooke and Kennedy (1988), reservoirs
have features not usually found with natural lakes and which can interfere with
any restoration project. Reservoirs usually have a very large drainage basin,
possibly covering several social or political units, and often with extensive areas
of nonpoint source discharges, making loadings very high and the probability of
improvement in stream quality low. As noted in Chapter 2, reservoirs are usually
dominated by a single, high-volume, source stream. This stream may not only
carry a heavy load of silt, organic matter, and nutrients but may also wash out
reservoir restoration treatments such as phosphorus inactivation, or reintroduce
undesirable organisms. Reservoirs can also have extensive areas of shallow
water with dense weed beds and high sediment nutrient release rates. It may be
possible, however, to improve an embayment of a reservoir.
The current uses of the lake or reservoir, or those planned for it, may be in-
compatible with the implementation of some restoration techniques, or may be
inconsistent with achievable improvements. For example, potable water sup-
plies must be treated with very great care. Not only are most herbicides banned
from water supplies, but some restoration procedures such as sediment removal
may require expensive, special equipment in order to protect raw potable water
quality.
Sometimes, limited, specialized uses of a lake or reservoir can make restora-
tion more likely. For example, weed control alone might suffice for a boating-
fishing-water skiing lake if algal blooms do not interfere with these uses. The
answer might be found in a management program of harvesting or herbicide
treatment. If the lake is also used for swimming, however, in-lake restoration
work and an expensive stream diversion project might become necessary.
Some lakes have always been highly productive, and no amount of money or
effort will make these waterbodies crystal clear and free of algae, weeds, and
shoals. Some geographic areas, or "ecoregions," have richer, more erodible
soils and higher annual precipitation. Loading to lakes of these regions, even
without cultural influences, will be high. Therefore, the goals of lake restoration
must be realistically set to limits imposed by natural background incomes of
substances and to the chemistry of lake sediments.
A factor often overlooked by lake users who desire restoration is the shape of
their lake's basin. Most lakes are small and shallow and thus offer ideal condi-
tions for plant growth. These lakes may be dominated by weed-choked areas;
their low volume may do little to dilute nutrient loading; and their sediments may
offer a rich supply of nutrients to rooted macrophytes. While some of these lakes
can respond well to restoration efforts, a combination of procedures may be re-
quired. In other lakes, such as those that average less than 7 feet deep, the costs
of deepening might be prohibitive, and other techniques might provide primarily
symptomatic relief at high cost.
The word restoration therefore must be considered in light of both what is
desired by the lake or reservoir users and what is possible. In many cases, con-
tinual maintenance work, in addition to the restoration procedure, will be re-
quired to maintain the desired water quality. And often the route to long-term
improvement will extend over several years while diagnostic/feasibility studies
are under way and restoration procedures are successively tested and imple-
mented. In all cases, whether involving lakes in which long-term improvement is
predicted or lakes in which it is impossible, an adequate diagnosis/feasibility
study is necessary to provide a rational basis for decisions prior to beginning
one or more in-lake restoration/management procedures.
6-3
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Lake and Reservoir

Restoration and Management

Techniques

Most of the techniques to manage and improve lakes and reservoirs were sug-
gested years ago. But only in the last decade have we accumulated enough well-
documented experiences to evaluate them. Much of this evaluation research
was supported through the U.S. EPA's Clean Lakes Program and by research
grants in basic and applied limnology from the U.S. EPA, the National Science
Foundation (NSF), and several other governmental and private agencies and
corporations. The much-needed further development of our knowledge of lakes
and reservoirs will require continued support by these organizations.
Five types of lake or reservoir problems are frequently encountered by lake
users. These are (1) nuisance algae; (2) excessive shallowness; (3) excessive
rooted plants ("weeds" or macrophytes) and their attached algae mats; (4)
drinking water taste, odor, color, and organics; and (5) fishing quality. For each
of these major problem areas, several in-lake techniques have been found to be
effective, long-lasting, and generally without significant negative impact when
used properly. These procedures will be described, under the appropriate
problem, with regard to their underlying ecological principles and mode(s) of ac-
tion, effectiveness (including brief case histories), potential negative impacts,
and additional benefits and costs. The reader will be referred to further reports in
the basic scientific literature. The less well-studied or less effective procedures
will also be briefly described.
Finally, Tables 6-1 and 6-7 will summarize these techniques in a matrix that
presents a qualitative evaluation of each for control of algae and macrophytes.
This evaluation represents the consensus of some lake and reservoir manage-
ment experts who have ranked these techniques with regard to short- and long-
term effectiveness, costs, and potential negative impacts. These matrices can be
used to aid in making decisions about the appropriate in-lake technique.

Basic Assumptions

It is very important for the reader to remember that the following discussions of
in-lake technique effectiveness, except where explicitly stated, always assumes
that the loadings of nutrients, silt, and organic matter to the lake or reservoir
have already been controlled. Most in-lake procedures will be quickly over-
whelmed by continued high income of substances. To repeat the lesson of
Chapter 5, the lake and watershed are coupled. In-lake programs can comple-
ment watershed efforts, as well. Algae, turbidity, and sedimentation problems,
for example, may persist despite load reductions or diversion projects unless an
in-lake procedure is also used.
As for restoration and management techniques that are not mentioned in this
Manual, in nearly every case, these procedures have not been described in the
open scientific literature and therefore have not had the benefit of testing, dis-
cussion, explanation, and criticism that is so vital to the development of techni-
ques of proven effectiveness and minimal negative impact. Caution should be
exercised in the use of a procedure not listed here.
6-4
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Problem I: Nuisance Algae

Biology of Algae

Algae can become serious nuisances in all aquatic habitats. In lakes and reser-
voirs two growth forms are most troublesome: mats of filamentous algae as-
sociated with weed beds, and free-floating microscopic cells, called
phytoplankton, which form green scum on the water surface and contribute to
taste and odor problems in drinking water. Algae reproduce almost exclusively
through cell division. When growth conditions are ideal (warm, lighted, nutrient-
rich), algae multiply rapidly and reach very high densities ("blooms") in a few
days.
The factors that control the abundance of phytoplankton, including blue-
green algae, form the basis for attempts to manage and limit them. Frequently
the quantity of algae in a lake can be shown to be directly related to the con-
centration of an essential plant nutrient. In many cases this element is phos-
phorus. Sometimes the lake and watershed can be manipulated to make
phosphorus concentration low enough to limit algal growth. Some restoration
techniques therefore concentrate on controlling the income of phosphorus or on
curtailing phosphorus release and cycling within the lake. Compared to phos-
phorus, other essential plant nutrients such as carbon and nitrogen are very dif-
ficult to manipulate to control algal growth. Other factors important to algal
growth can be manipulated to produce long-term control. Light may be limiting
to growth, when nutrients are very abundant, and can be manipulated to
produce long-term control, sometimes by artificially circulating cells into deep,
dark water. In other cases, particularly where nutrients cannot be manipulated,
control can be achieved by enhancing grazing on cells by animals. All of these
procedures, and others, will be described in the following paragraphs.
Filamentous algae are very difficult to control. With the exception of algicide
applications, procedures to accomplish this are often associated with proce-
dures to control weeds and, therefore, will be discussed in the macrophyte sec-
tion.
Algae/Techniques with

Long-Term Effectiveness

Phosphorus Precipitation and
Inactivation

• PRINCIPLE. The release of phosphorus stored in lake sediments can be so
extensive that algal blooms persist even after incoming phosphorus has been
significantly lowered, as seen in the Shagawa Lake example in Chapter 4. Phos-
phorus precipitation removes phosphorus from the water column. Phosphorus
inactivation, on the other hand, is a technique to achieve long-term control of
phosphorus release from lake sediments by adding as much aluminum sulfate
to the lake as possible within the limits dictated by environmental safety (see
Potential Negative Impacts).
6-5
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These two techniques are used after nutrient diversion. Both attempt to keep
phosphorus concentration in the water column low enough to limit algal growth.

• MODE OF ACTION. Iron, calcium, and aluminum have salts that can com-
bine with (or sorb) inorganic phosphorus or remove phosphorus-containing par-
ticulate matter from the water column as part of a floe. Of these elements,
aluminum is most often chosen because phosphorus binds tightly to its salts
over a wide range of ecological conditions, including low or zero dissolved
oxygen. In practice, aluminum sulfate (alum) or sodium aluminate is added to
the water, and pin-point, colloidal aggregates of aluminum hydroxide are
formed. These aggregates rapidly polymerize and grow in size into a visible,
brownish floe or precipitate that settles to the sediments in a few hours, carrying
phosphorus sorbed to its surface and bits of organic and inorganic paniculate
matter in the floe. After the floe settles to the sediment surface, the water will be
very clear. If enough alum is added, a layer of 1-2 inches of aluminum hydroxide
will cover the sediments and prevent phosphorus from entering the water
column as an "internal load" (Chapter 2). In many lakes, assuming sufficient
diversion of external nutrient loading, this will mean that algal cells will become
starved for this essential nutrient. In contrast, some untreated lakes, even with
adequate diversion of nutrients, will continue to have algal blooms that are sus-
tained by sediment nutrient release. Good candidate lakes for this procedure are
those that have had nutrient diversion and have been shown, during the diag-
nostic/feasibility study, to have high internal phosphorus release. Impoundments
are usually not good candidates because of an inability to limit nutrient income.
Treatments of lakes with low doses of alum may effectively remove phosphorus
(called phosphorus precipitation), but may be inadequate to provide long-term
control of phosphorus release from lake sediments (phosphorus inactivation).
Dissolved inorganic phosphorus, the phosphorus form that many believe
algae use for growth and reproduction, sorbs tightly to this floe. After the floe
falls to the sediment surface, it appears to continue to sorb phosphorus as it
slowly settles and consolidates with the sediments, and in this way acts as a
chemical barrier to phosphorus release from the sediments.

• EFFECTIVENESS. This procedure has proven to be highly effective and
long-lasting in thermally stratified natural lakes, especially where an adequate
dose has been given to the sediments and where sufficient diversion of nutrient
incomes has occurred. There has been almost no experience in using this pro-
cedure in reservoirs. In reservoirs, adequate nutrient diversion is very difficult,
and therefore treatment effectiveness might be very brief; in addition, high flows
may wash the floe out or quickly cover it with another layer of nutrient-rich silt.
Case histories have been extensively documented in Cooke and Kennedy
(1981, 1988) and Cooke et al. (1986). Successful treatments have been made to
large, deep lakes as well as to the more common smaller ones and farm ponds.
Treatment longevity has extended beyond 10 years in some cases and to 5
years in many. Shallow, nonstratified lakes appear to have shorter periods of ef-
fectiveness of the treatment than stratified lakes and thus have not proven to be
ideal candidates for alum treatment. In some cases the phosphorus-sorbing floe
layer has become covered with new, phosphorus-rich sediments.
Typical lake responses to alum treatment include

• sharply lowered phosphorus concentrations

• greatly increased transparency (and improved conditions for weeds)
• algal blooms of much reduced intensity and duration
6-6
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• POTENTIAL NEGATIVE IMPACTS. The addition of aluminum salts to lakes
has the potential for serious negative impacts, and care must therefore be exer-
cised with regard to dose. The potential for toxicity problems is directly related
to the alkalinity and pH of the lake water. pH and alkalinity must be determined in
the diagnostic studies (see Chapter 3) before this treatment is implemented.
When alum or aluminum sulfate (Ala(SO4)3 ' 14 HaO) is added, aluminum
hydroxide (AI(OH)s) is readily formed in water at pH 6 to 8. This compound is the
visible precipitate or floe described earlier. However, pH and alkalinity of the
water will fall at a rate dictated by the initial alkalinity or buffering capacity of the
water. In soft water, only very small doses of alum can be added before alkalinity
is exhausted and the pH falls below 6. At pH 6 and below, AI(OH)2 and dissolved
elemental aluminum (Al+3) become the dominant forms. Both of these can be
toxic to lake species. Well-buffered, hard-water lakes are therefore good can-
didates for this type of lake treatment because a large dose can be given to the
lake without fear of creating toxic forms of aluminum. Soft-water lakes must be
buffered, either with sodium aluminate or carbonate-type salts, to prevent the
undesirable pH shift and to generate enough AI(OH)3 to control phosphorus
release. Dose is therefore lake-specific. Details of dose determination can be
found in Cooke et al. (1986).
Another potentially negative effect of phosphorus inactivation is the sharp in-
crease in water transparency, which may allow an existing weed infestation to
spread into deeper water.

• COSTS. Phosphorus inactivation, the addition of alum to lake sediments for
long-term control for phosphorus release, will have a high initial cost. For ex-
ample, at West Twin Lake, Ohio, a 40-acre (16-ha) area of lake sediments was
dosed with 100 tons of alum (Cooke et al. 1982). At current prices, that would
cost about $14,000. However, labor is the real cost and is determined by the
amount of chemical to be added (Cooke et al. 1986). More rapid, less expensive
application systems are under development. It should be noted that phosphorus
inactivation is a long-term treatment so that costs are amortized. Peterson
(1982a) has shown that on this basis, phosphorus inactivation is apparently less
costly than sediment removal for nutrient and algal control. If a dose sufficient to
simply remove phosphorus from the water column is used, initial costs could be
much lower, but long-term effectiveness may be sharply reduced.

Sediment Removal

• PRINCIPLE. The release of algae-stimulating nutrients from lake sediments
can also be controlled by removing the layer of the most highly enriched
materials. This may produce significantly lower in-lake nutrient concentrations
and less algal production, assuming that there has been adequate diversion or
treatment of incoming materials.

• MODE OF ACTION. Several types of dredging equipment exist for use in
varying circumstances (Cooke et al. 1986). A hydraulic dredge equipped with a
cutterhead is the most common choice. In this design, the cutter loosens sedi-
ments that are then transported as a slurry of 80-90 percent water through a
pipeline that traverses the lake from the dredging site to a remote disposal area.
Figures 6-1 and 6-2, from Barnard (1978), illustrate the typical dredge and its
side-to-side path across the lake.
Other types of dredges, including the grab-bucket design, are used in special
situations.
6-7
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FLOATING LINE
. SPUD WELLI
•• SPUD
ENGINE HOUSE LEVER ROOM
MAIN PUMP x HOIST ., -
C^' *
HULL
Figure 6-1.-Configuration of a typical cutterhead dredge (from Barnard, 1978).
DREDGE
PORT SWING WIRE
B © D
0C
WINCH
ADVANCE

-SPUD (DOWN)
FRONT
D

WINDROW

STARBOARD SWING WIRE
Figure 6-2.-Spud-stabbing method for forward movement, and resultant patterns of the cut
(from Barnard, 1978).

Normally, a permit from the U.S. Army Corps of Engineers will be required
before dredging can commence, even if a private lake is involved.

• EFFECTIVENESS. Sediment removal to retard nutrient release can be highly
effective. A good example is that of Lake Trummen, Sweden, where the upper
3.3 feet of sediments were extremely rich in nutrients. This layer was removed,
increasing lake mean depth from 3.6 feet to 5.76 feet, and disposed of in diked-
off bays or upland ponds. Return flow from the ponds was treated with alum to
6-8
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remove phosphorus. The total phosphorus concentration in the lake dropped
sharply and remained low for 9 years (Fig. 6-3). Other case histories have been
described by Peterson (1982b) and Cooke et al. (1986). While removing the en-
tire nutrient-rich layer of sediment can control algae, dredging is most frequently
done to deepen a lake or to remove and control macrophytes (see the section in
this chapter on Macrophyte Control Techniques).

TOTAL PHOSPHORUS, MG V1
1.0 -
0.5 -
Figure 6-3.-Total phosphorus concentration in Lake Trummen, Sweden, before and after
dredging (courtesy of Gunnar Anderson, Department of Limnology, University of Lund, Swe-
den). Shaded line indicates period of dredging.

• POTENTIAL NEGATIVE IMPACTS. The potential for serious negative im-
pacts on the lake and surrounding area is very high. Many of these problems are
short-lived and can be minimized with proper planning. Among the most serious
environmental problems is the failure to have a disposal area of adequate size to
handle the high volume of turbid, nutrient-rich water that accompanies the sedi-
ments. Unless the sediment water slurry can be retained long enough for
evaporation, the runoff water will be discharged to a stream or lake. Turbidity,
algal blooms, and dissolved-oxygen depletions may occur in the receiving
waters. These problems may also develop in the lake during the dredging opera-
tion itself, but this is usually temporary.
Finally, an analysis of the sediments for the presence of heavy metals (par-
ticularly copper and arsenic, both of which have been extensively used as herb-
icides), chlorinated hydrocarbons, and other potentially toxic materials should
be carried out prior to dredging. Special precautions, some of them expensive,
will be required if these substances are present in high concentrations. Chapter
8 describes implementation procedures and permit procedures, which are criti-
cal to the success of a dredging project.
While the potential for negative impacts is high, proper dredge selection and
disposal area design will minimize them.

• COSTS. Sediment removal is expensive. Peterson (1981) reported a cost
range of $0.18 cubic yard (yd3) to $10.71 yd3 ($ 1975) for 64 projects, and found
that costs from $0.95 to $1.33 (in 1975 dollars) were common and could be con-
sidered "reasonable" for hydraulic dredging. Dredging costs are highly variable,
depending upon site conditions, access, nature of the sludge, and other factors.
In addition, the costs Peterson (1981) reported do not include disposal,
transport, or monitoring costs. Peterson (1982a) concludes that phosphorus in-
activation is somewhat less expensive than sediment removal as a method to
control nutrient release.
6-9
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Dilution and Flushing
• PRINCIPLE. Lake waters that have low concentrations of an essential
nutrient are unlikely to exhibit algal blooms. While the ideal is to divert or treat
nutrient-rich waters before they empty into the lake, it is possible to lower the
concentration of nutrients within the lake and to flush out algal cells by adding
sufficient quantities of nutrient-poor water from some additional source (dilu-
tion). High amounts of additional water, whether low in nutrients or not, can also
be used to flush algae out from the lake faster than they grow.

• MODE OF ACTION. Phosphorus is often the nutrient that limits algal growth.
Its concentration in the lake water is a function of its concentration in incoming
water, the flushing rate or residence time of the lake or reservoir, and the net
amount lost to the sediments as particles settle during water passage through
the system. When water that is low in phosphorus is added to the inflow, the ac-
tual phosphorus loading will increase, but the mean phosphorus concentration
will decrease, depending upon initial flushing rate and inflow concentration. Con-
centration will also be affected by the degree to which loss of phosphorus to
sediments decreases and counters the dilution. Uttormark and Hutchins (1980)
conclude that lakes with low initial flushing rates are poor candidates because
in-lake concentration could increase unless the dilution water is essentially
devoid of phosphorus. Internal phosphorus release could further complicate the
effect.
Dilution also produces washout of cells. These facts point out the need for a
water and nutrient budget, as well as a study of basin volume, before prescribing
a procedure such as this one.
Flushing can control algal biomass by cell washout. The flushing rate must be
near the cell growth rate to be effective. Flushing rates of 10-15 percent of the
lake volume per day are believed to sufficient (Cooke et al. 1986).

• EFFECTIVENESS. Very few documented case histories of dilution or flush-
ing exist, in part because additional water is not often available, especially water
that is low in nutrients. The best documented case of dilution is that of Moses
Lake, Washington (Welch and Patmont, 1980; Cooke et al. 1986), where low-
nutrient Columbia River water was diverted through the lake. Water exchange
rates of 10-20 percent per day were achieved, and dramatic improvements in
transparency and algal blooms occurred. Effectiveness of this method is very
high.

• POTENTIAL NEGATIVE IMPACTS. Outlet structures must be capable of
handling the added discharge, and the increased volume released downstream
could have negative effects. Water used for dilution or flushing should be tested
before it is introduced to the lake or reservoir to be sure that no toxics are
present.

• COSTS. Costs will vary greatly from site to site, depending upon the need for
pumps, extensive engineering, outlet structure repair, and the proximity of the
new water.
6-10
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Algae/Additional Procedures

for Control

None of these techniques is considered to be completely ineffective. However,
none is well enough understood or has produced enough positive results to be
considered an established and effective, long-term procedure. This group of
techniques will be briefly described here, and the reader contemplating their use
is referred to Cooke et al. (1986) and Cooke and Kennedy (1988) for detailed dis-
cussions of case histories and negative environmental impacts.

Artificial Circulation

The objective of artificial circulation is to eliminate thermal stratification, or to
prevent its formation, through the injection of compressed air from a pipe or
ceramic diffuser at the lake's bottom. The rising column of bubbles, if sufficiently
powered, will produce lake-wide mixing at a rate that will eliminate temperature
differences between top and bottom waters. Control of algal blooms may occur,
possibly through one or more of these processes:
1. In light-limited algal communities, mixing to the lake's bottom will increase
a cell's time in darkness, leading to reduced net photosynthesis.
2. The introduction of dissolved oxygen to the lake's bottom may inhibit phos-
phorus release from sediments, curtailing this internal nutrient source.
3. Rapid circulation and contact of water with the atmosphere, as well as the
introduction of carbon dioxide-rich bottom water during the initial period of
mixing, may increase the water's carbon dioxide content and lower pH, leading
to a shift from blue-green algae to less noxious green algae.
4. Zooplankton that consume algae may be more difficult for sight-feeding
fish to prey upon when mixed to the lake's bottom. If this improves zooplankton
survival, consumption of algal cells may also increase.
Highly variable results from case to case have occurred. In most instances
problems with low dissolved oxygen (which can occur with deep discharge
dams, for example) have been solved. In about half the cases, and where very
small temperature differences from top to bottom have been maintained all sum-
mer, algal blooms have been reduced (see reviews by Pastorok et al 1981-
Cooke et al. 1986). In other cases, phosphorus and turbidity have increased and
transparency has decreased.
Failure to achieve the desired objective may be caused by lake chemistry or
equipment. Lorenzen and Fast (1977) conclude that to adequately mix a lake an
air flow of at least 1.3 cubic feet per minute (1.3 ft3/min) per acre of lake surface
is required to maintain oxygen within the lake. Underdesign is a major cause of
failure for this technique. This is a highly specialized area, and the system should
be designed by a professional who is experienced in artificial circulation Correct
air flow pressure depends on site conditions. Algae control may also depend on
a particular lake's water chemistry.
Costs are low, and will primarily be for the compressor and installation of
pipes and diffuser.
6-11
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Hypolimnetic Aeration
Hypolimnetic aeration is different from artificial circulation in objective and
operation. Artificial circulation employs a curtain of bubbles to achieve complete
mixing and isothermal conditions, but hypolimnetic aeration most commonly
employs an airlift device to bring cold hypolimnetic (the deep, stagnant water
layer) water to the surface of deep lakes. The water is aerated by contact with
the atmosphere, some gases such as carbon dioxide and methane are lost, and
then the water is returned to the hypolimnion (Figs. 6-4 and 6-5). There is no in-
tention to destratify the lake.
: IRON PIPE
Figure 6-4.-Destratification system installed at El Capitan Reservoir, California (from Loren-
zen and Fast, 1977).
A common use of this procedure is to maintain a cold-water fishery in a lake
where the hypolimnion is normally oxygen-free. Another use is to eliminate taste
and color problems in drinking water w!*ridrawn from a cold hypolimnion. This is
done by introducing oxygen, which v produce chemical conditions that will
favor precipitation of iron and manganese, the elements most often associated
with color in drinking water. Also, the procedure could be used to improve the
quality of water discharged downstream from a hypolimnetic discharge.
There is little documentation of its successful use in control of nuisance algae,
although there is evidence that hypolimnetic aeration can control phosphorus
release from lake sediments by promoting its combination with iron. Iron addi-
tions to the hypolimnion during aeration could enhance phosphorus removal
and thereby control internal phosphorus release. Hypolimnetic aeration could
become a type of phosphorus inactivation procedure under high oxygen-high
iron conditions, and in this way perhaps promote some control of algae.
Hypolimnetic aerators need sufficiently a large hypolimnion to work properly;
consequently, their use in shallow lakes and reservoirs should be viewed with
great caution.
6-12
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Figure 6-5.-Aqua Technique's Umno partial air-lift hypolimnetic aerator. The arrows indi-
cate the direction of air flow. (Courtesy of Aqua Technique).

Costs of hypolimnetic aeration are dictated by the amount of compressed air
needed (a function of hypolimnion area, the rate of oxygen consumption in the
lake, and the degree of thermal stratification). A procedure for calculating this is
presented in Cooke et al. (1986).
Hypolimnetic Withdrawal

The cold, deep layers of a thermally stratified eutrophic lake or reservoir may
have higher nutrient concentrations than upper layer waters. Any vertical
entrainment of this water to the epilimnion will introduce nutrients to it and pos-
sibly trigger an algal bloom. This can happen naturally as the lake's epilimnion
thickens during the summer, during the passage of a cold front, and during
spring and fall turnover periods. The objective of hypolimnetic withdrawal is to
6-13
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remove this nutrient-rich, oxygen-free water either through a deep outlet in the
dam or by a siphon, thereby accelerating the lake's phosphorus loss, resulting in
a decrease in phosphorus concentration in surface waters.
There are few documented case histories of this procedure (reviewed in
Cooke et al. 1986; Nurnberg, 1987). Gachter (1976) describes a very successful
project with a small, Swiss lake where phosphorus and nitrogen concentrations
declined, dissolved oxygen and transparency increased, and blue-green algal
blooms decreased following withdrawal.
Serious negative impacts are possible. The discharge water may be of poor
quality and may require aeration or other treatment. State or Federal regulatory
agencies may require a permit to discharge this water. Also, hypolimnetic
withdrawal could produce thermal instability and thus destratification, which
could introduce nutrient-rich, anoxic water to the epilimnion. An algal bloom
could ensue. Negative effects to biota appear to be unlikely.
Costs should be comparatively low and would involve a capital outlay for
pump, pipe, and an aeration device.
Sediment Oxidation

This is a new and highly experimental procedure (Ripl, 1976), and few case his-
tories exist. The objective of the procedure is to decrease phosphorus release
from sediments, as with phosphorus inactivation. Iron as ferric chloride is added
to sediments, if they are low in iron, to enhance phosphorus precipitation. Lime
is also added to bring sediment pH to 7.0-7.5, the optimum pH for denitrification.
Then calcium nitrate is injected into the top 10 inches of sediments to promote
the oxidation or breakdown of organic matter and denitrification. The entire pro-
cedure is often called RIPLOX after its originator (Ripl, 1976).
Lake Lillesjon, a 10.5-acre Swedish lake with a 6.6 foot mean depth, was the
first to be treated, at a cost of $112,000. Most costs were for equipment develop-
ment and the preliminary investigation. Chemical costs were about $7,000. The
treatment lowered sediment phosphorus release dramatically and lasted at least
2 years. A portion of a Minnesota lake was treated, but high external loading
overwhelmed its effects. No negative impacts have been reported.

Food Chain Manipulation

A developing body of evidence supports the conclusion that the amount of algae
in the open water of a lake or reservoir might be controlled as much by
zooplankton grazing as by the quantity of nutrients. Zooplankton are micro-
scopic, crustacean animals that can, as a community of several species, filter up
to the entire epilimnion each day as they graze on algae, bacteria, and bits of or-
ganic matter. They are found in every lake and reservoir. The most efficient
grazers, which remove more particles over the widest range of particle sizes, are
the largest sized zooplankton species. These large zooplankton, however, are
preferentially eaten by fish, including the fry of nearly every fish species and the
adults of bluegill, pumpkinseed, perch, alewives, and others. In lakes dominated
by adults of species such as largemouth bass, walleye, and northern pike, large-
bodied zooplankton are more likely to survive and grazing on algae can be very
high. Conversely, lakes dominated by small panfish have the possibility of in-
tense feeding on zooplankton and may have severely reduced grazing on algae
and thus more extensive algal blooms. This type of algal control by animals in
the food chain is "top down" control and differs fundamentally from our usual
conception of algal control through nutrient limitation. Figures 6-6 and 6-7 are
pictorial models of these food web interactions.
6-14
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PISCIVOROUS
FISH
r
EAT
1-2 FT
PLANKTIVOROUS
FISH
"-1 FT
EAT
ZOOPLANKTON
T
EAT
1/10 IN
ALGAE
r
MICROSCOPIC
USE

NUTRIENTS
NUTRIENTS
RECYCLE

A
BENTHIC
ORGANISMS
Figure 6-6.-The aquatic food chain.
6-15
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Comparison of Top-down Effects on Food Chain
Low predator biomass
^-
i
High zooplankton
feeders biomass
Low zooplankton
biomass
High phytoplankton
biomass
• Low Secchi depth
• HighpH
• Stressed 02 supply
High predator biomass
1
Low zooplankton
feeders biomass
L
High biomass of
large-bodied zooplankton
Role of
carnivorous
zooplankton
uncertain
Low biomassl I Possibly high
of small | biomass of
j phytoplankton 11 large, colonial
t 11 phytoplankton
Role of
nutrient load
and
hydrophysical
conditions
uncertain
• High Secchi depth
• Normal or high pH
• Normal or extreme
values
Figure 6-7.-Hypothetical scheme showing the connections involved in biomanipulation.
6-16
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Shapiro et al. (1975) have defined biomanipulation as the procedure of en-
hancing grazer control of algae by eliminating zooplankton-eating fish through
the use of fish poisons or fish winterkill, or by adding enough predators to limit
the consumption of beneficial zooplankton by small fish. With such manipula-
tions, it might be possible to improve a lake without an expensive nutrient diver-
sion. However, it should be noted that a simple addition of predatory fish, such
as walleyes, may not be sufficient to produce any measurable control of algae.
This might be true in very large eutrophic lakes. As well, mortality among added
fish could be high. The evidence of the beneficial effects of controlling the den-
sity of stunted panfish is sound enough to warrant projects involving lake users
in the control or removal of small fish, especially on small lakes.
Other conditions in addition to heavy grazing by fish might reduce
zooplankton grazing on algae. An oxygen-free hypolimnion, common in
eutrophic lakes, eliminates this zone as a daytime refuge of zooplankton from
sight-feeding fish and thus enhances zooplankton mortality. An aeration device
might eliminate this problem. Another cause of zooplankton mortality, as
pointed out by Shapiro (1979), is from the toxic effects of pesticides that enter
the lake with agricultural runoff. The use of copper sulfate for temporary algal
control can also produce significant zooplankton mortality at doses far below
those needed for algal control. Severe mortality of zooplankton could explain
the common "rebound" of algae following a copper treatment.
An extensive review of the evidence about this method of algae control is
found in Cooke et al. (1986) and Cooke and Kennedy (1988). Figure 6-7, from
Benndorf et al. (1984), summarizes biomanipulation. This method may be one of
the few alternatives for lakes where nutrient diversion is not feasible. It means
that removal of those "trophy" bass and northerns by fishermen makes little
ecological sense where clear water is desired. It also makes poor ecological
sense to stock a lake with zooplankton-eating fish such as gizzard shad where
clear water is desired. Food web manipulation is probably not feasible in reser-
voirs because undesirable fish may be continually introduced.
Another type of biomanipulation that could improve lake transparency is to
eliminate fish such as the common carp or bullheads that are bottom browsers.
Browsing has been shown to release significant amounts of nutrients to the
water column as these fish feed and digest food. Removing such fish, however,
is exceedingly difficult since they are tolerant of very low levels of dissolved
oxygen and high doses of fish poisons.
Costs of biomanipulation are not known. Fish poisons are expensive and in
many cases would entail an expensive cleanup of dead fish. The cost of restruc-
turing a food web through enhancement of a predatory fish population will, of
course, be specific to each lake. Because of the high interest in fish and fishing
at most lakes, significant volunteer labor and expertise might be available. State
fish and game personnel would be an excellent resource for stocking densities
and species likely to survive in any given area.

Algicides

Copper sulfate (CuSC-4) is the most widely employed algicidal chemical. It is
registered for use in potable waters, although restrictions apply in some States.
Simazine is also extensively used to control algae.
Copper inhibits algal photosynthesis and alters nitrogen metabolism. In prac-
tice, copper sulfate is applied by allowing granules placed in burlap or nylon
bags to dissolve as they are towed behind a boat. In alkaline waters (150 mg
CaCOa (calcium carbonate) per liter, or more) or in waters high in organic mat-
ter, copper can be quickly lost from solution and thus rendered ineffective. In
these cases, a liquid chelated form is often used. This formulation allows the
6-17
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copper to remain dissolved in the water for a period long enough to kill algae.
Both planktonic algae, including nuisance blue-green species, and species form-
ing filamentous mats in weed beds will be killed by doses of 1 -2 mg CuSCWL
(0.8 milligrams of copper per liter (mg Cu/L)).
Copper sulfate is often effective, although the response may be brief and re-
quire additional applications. There are several undesirable impacts, and it is in
no way a lake restoration agent since no causes of the problem are addressed.
Negative impacts include toxicity to fish and the occurrence of dissolved
oxygen depletions when overly large areas are treated within a short period of
time. Hansen and Stefan (1984) have provided one of the very few examinations
of the long-term ecological consequences of the addition of a toxic substance to
a lake for the purpose of short-term relief from algal blooms. They report that 58
years of copper sulfate use in a group of Minnesota lakes, while effective at times
for the temporary control of algae, have produced dissolved oxygen depletions,
increased internal nutrient cycling, occasional fishkills, copper accumulation in
sediments, increased tolerance to copper by some nuisance blue-green algae,
and undesirable effects to fish and the fish-food community. They conclude that
short-term control (days) of algae has been traded for long-term degradation of
the lakes.
Costs of algicides are related to dose, to longevity of effect, and to applicator
fees. The usual dose of granular copper sulfate for control of planktonic algae is
about 5.4 Ibs per acre-foot of water. An acre-foot is an acre of water 1 -foot deep.
The most commonly used chelated products are applied at 0.6 gallons per acre-
foot. The price for chemicals in 1986 was about $5.15 per acre-foot for granular
copper sulfate at a dose of 5.4 Ibs per acre-foot, and $20.10 per acre-foot of a
chelated product at a dose of 0.6 gallons per acre-foot. Application procedures
are more rapid for the liquid chelated form, and there have been claims that its
effect on algae will last longer than granular copper sulfate, suggesting that an-
nualized costs for use of the chelated form, especially in hard-water lakes, may
be similar to the granular form. Fees of the licensed, insured applicator are not
included here.
Algae/Summary of
Restoration and Management
Techniques
Table 6-1 summarizes the procedures described in the preceding sections.
Qualitative evaluation of the procedures with regard to short- and long-term ef-
fectiveness, costs, and potential negative impacts are presented. These judg-
ments are the consensus of a panel of 12 lake and reservoir restoration experts.
Problem II: Excessive

Shallowness
The incomes of silt and organic matter from agricultural erosion, construction,
shoreline collapse, urban drainage, and other sources can rapidly increase the
area of very shallow water. Not only can this interfere with recreational activities
6-18
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Table 6-1.—Comparison of lake restoration and management techniques for
control of nuisance algae
TREATMENT (ONE APPLICATION)
Phosphorus Inactivation
Dredging
Dilution
Flushing
Artificial Circulation
Hypolimnetic Aeration
Sediment Oxidation
Algicides
Food Chain Manipulation
Rough Fish Removal
Hypolimnetic Withdrawal
SHORT/
TERM
EFFECT
E
F
G
F
F
F
G
G
G
G
G
LONG/
TERM
EFFECT
E
E
G
F
?
7
E
P
9
P
G
NEGATIVE
COST
G
P
F
F
G
G
F
G
E
E
G
EFFECTS
F-G
F-G
G
G
F
F
?
P
9
9
F
E = Excellent F = Fair
G = Good P = Poor
such as boating, but shallow, nutrient-rich sediments are ideal areas for growth
of nuisance aquatic plants.
Details about sediment removal were provided in an earlier section in this
chapter. This procedure is the only practical way to bring about lake or reservoir
improvement when shoaling is a problem, and dredging has therefore become
one of the most frequently prescribed techniques. A properly designed feasibility
study of the lake and the disposal sites is an essential first step, and in nearly all
cases a permit from the U.S. Army Corps of Engineers will be required. Dredging
projects are expensive, and have the potential for severe negative impacts un-
less correctly designed, but they are often highly effective. Continual incomes of
silt will return the lake to its predredged condition, and therefore silt sources
should be controlled.
Problem III: Nuisance Weeds

(Macrophytes)

Biology of Macrophytes

Overabundant rooted and floating plants are a major nuisance to lake and reser-
voir users. In extreme cases, particularly in ponds and in shallow, warm, well-
lighted lakes and waterways of the Southern United States, weeds (sometimes
called macrophytes) can cover the entire lake surface. Weeds obviously inter-
fere with recreation and detract from aesthetic values of a lake. They can also in-
troduce significant quantities of nutrients and organic matter to the water
column, perhaps stimulating algal blooms and raising dissolved oxygen con-
sumption.
Macrophytes are generally grouped into classes called emergents (repre-
sented by cattails), floating-leaved (water lilies), and submergents (pondweeds),
plus the mats of filamentous algae that develop in weed beds. Understanding
the factors that control weed growth is the first step in controlling weeds.
Macrophytes reproduce both by the production of flowers and seeds and by
asexual propagation from fragments and shoots extending from roots. Growth
rates of macrophytes can be very high.
6-19
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Available light is a very significant factor in where the weeds will grow and
how profusely. Submergent plants will grow profusely only where underwater il-
lumination is sufficient. Steep-sided lakes therefore support a much smaller
development of common nuisance weeds because most of the sediments are
too dark or too deep. Similarly, turbid lakes and reservoirs are unlikely to have
dense beds of submerged plants. Thus high silt incomes to a lake can create a
favorable weed habitat as the lake fills in, unless the silt loading also creates
severe turbidity. Significant reductions in algal blooms can also enhance light
penetration and allow weeds to grow better.
Since most macrophytes obtain their nutrients via roots, they can therefore be
abundant in lakes in which nutrient concentration of the water column has been
reduced through diversion. When the sediments are either highly organic or
highly inorganic (sand), macrophyte growth may be poor because it is more dif-
ficult for roots to obtain nutrients in these sediment types. In these two extremes,
emergent plants may replace submergents because their more extensive root
systems are better adapted to these conditions. Further discussions of these
ideas regarding macrophyte biology can be found in Barko and Smart (1986)
and Duarte et al. (1986).
No native animals have been found that graze on macrophytes at rates suffi-
cient to control them. Biological controls therefore are confined to exotic
animals.
Short-term management of macrophytes through cutting or herbicides has
been practiced for years. The development of ecologically sound procedures to
produce long-term control has lagged far behind, in part because we have, until
recently, understood very little about macrophyte physiology and the environ-
mental factors that control their growth. The following paragraphs briefly
describe the procedures known to produce long-term control. Since short-term
management techniques are likely to continue to be used, for example during
implementation of a longer term treatment, these are described in a separate
section.
Macrophytes/Long-Term

Control Techniques

Sediment Removal and Sediment Tilling

• PRINCIPLE. Sediment removal can limit submerged weed growth through
deepening, thereby producing light limitation, or by removing favorable sedi-
ments to growth and leaving sand. Both dredging and rototilling can limit plants
through removal of roots.

• MODE OF ACTION. Sediment removal was described in some detail in ear-
lier paragraphs on algal control. The amount of sediments removed, and hence
the new depth and associated light penetration, is critical to successful long-
term control of rooted, submerged plants. There appears to be a direct relation
between water transparency, as simply determined with a Secchi disk, and the
maximum depth of colonization (MDC) by macrophytes. Canfield et al. (1985)
6-20
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provide these equations to estimate MDC in Florida and Wisconsin from Secchi
disk measurements:

STATE EQUATION
Florida log MDC = 0.42 log SD + 0.41
Wisconsin log MDC = 0.79 log SD + 0.25
where SD = Secchi depth in meters

For example, suppose the Secchi transparency of a Florida lake is usually
about 6 feet. How far from shore can we expect to find rooted macrophytes (the
MDC)? A hand-held calculator can be used to obtain the answer and to suggest
how deep near-shore areas would have to be to have minimal quantities of
rooted, submerged macrophytes. In this case, transform 6 feet to meters (feet x
0.305 = meters). This will be 1.83 meters. The log of 1.83 is 0.26. Then substitute
this in the equation for a Florida lake, as follows:

log MDC = (0.42xlog1.83) + 0.41
= (0.42x0.26) + 0.41
= 0.52

To obtain depth (MDC) in meters use the calculator to find the antilog of
0.52 = 3.31 meters. To convert meters to feet, multiply this answer by 3.28
= 10.9 feet. This means that for a Florida lake with a Secchi disk transparency of
about 6 feet, we would expect some submerged weeds in 11 feet of water and
more weeds in progressively shallower water. In this example, very large
amounts of sediments might have to be removed in order to create large areas
of the lake with depths of 10-11 feet. Examination of a bathymetric map (Chapter
3) will indicate whether this is the case. The equation also indicates that actions
that greatly improve water clarity, such as erosion control or phosphorus inac-
tivation, may enhance weed distribution and abundance.
Rototilling and the use of cultivation equipment are newer procedures
presently under development and testing by the British Columbia Ministry of En-
vironment (Newroth and Soar, 1986). A rototiller is a barge-like machine with a
hydraulically operated tillage device that can be lowered to depths of 10-12 feet
(3-4 meters) for the purpose of tearing out roots. Further descriptions are found
in Cooke et al. (1986). Also, if the water level in the lake can be drawn down, cul-
tivation equipment pulled behind tractors on firm sediments can achieve 90 per-
cent root removal.

• EFFECTIVENESS. The use of sediment removal for long-term control of
macrophytes is effective when the source of sediments is controlled. Dredging
below the lake's photic zone will prevent macrophyte growth. The cost of dredg-
ing, however, often places the use of this technique in doubt.
Newroth and Soar (1986) reported that rototilling to remove watermilfoil is as
effective as three to four harvesting operations.

• POTENTIAL NEGATIVE IMPACTS. The negative impacts of sediment
removal have already been discussed under algal control.

• COSTS. Costs were described earlier under algal control.
Newroth and Soar (1986) have studied costs of the rototiller and amphibious
cultivator and found them to be similar to herbicides and harvesting, but opera-
tion speed is slower.
6-21
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Water Level Drawdown

• PRINCIPLE AND MODE OF ACTION. Exposing sediments to prolonged
freezing and drying provides an opportunity to carry out several management
procedures. Some rooted plant species are permanently damaged by these
conditions and the entire plant, including roots and perhaps seeds, is killed if ex-
posed to freezing for 2-4 weeks. Other species, however, are either unaffected or
enhanced. Drawdown also allows repair of dams and docks, fish management,
sediment removal, and installation of sediment covers to control plant growth.

• EFFECTIVENESS. Cooke et al. (1986) summarize the responses of 74
aquatic plants to drawdown. Table 6-2 lists the responses of some common
species.
Many case histories exist, and they illustrate three important facts:
1. Freezing and desiccation are required; wet, cold lake sediments, or wet
sediments covered with snow may have little negative effect on plants.
2. The technique is species-specific.
3. Successful drawdown-freezing operations should be alternated every 2
years with no drawdown so that resistant species do not become firmly estab-
lished.

Table 6-2.—Responses of common aquatic plants to drawdown
DECREASE
Coontail (Ceratophyllum demersum)
Brazilian elodea (Elodea = Egeria densa)
Milfoil (Myriophyllum spp.)
Southern naiad (A/ay'as guadalupensis)
Yellow Water Lily (Nuphar spp.)
Water Lily (Nymphaea odorata)
Bobbin's Pondweed (Potamogeton robbinsii)

INCREASE
Alligator Weed (Alternanthera philoxeroides)
Hydrilla (Hydrilla verticillata)
Bushy Pondweed (A/a/as flexilis)

VARIABLE
Water Hyacinth (Eichhornia crassipes)
Common Elodea (Elodea canadensis)
Cattail (Typha latifolia)

Two case histories illustrate these points. Beard (1973) describes winter draw-
down of Murphy Flowage, Wisconsin. Before drawdown, 75 acres were closed in
spring and summer to fishing because of a dense infestation of pondweeds
(Potamogeton robbinsii, P. amplifolius), coontail, Eurasian watermilfoil, and
water lily. Drawdown opened 64 acres, and although some resistant plants in-
creased, fishing improved. Geiger (1983) used winter drawdown in an attempt to
control Eurasian watermilfoil in an Oregon lake. The mild, wet winter of the
Pacific Northwest did not provide sufficient freezing, and the weeds increased
and had to be treated with 2,4-D.

• POTENTIAL NEGATIVE IMPACTS. Algal blooms have occurred after some
drawdowns. The causes are unclear, but may be related to nutrient release from
sediments or to an absence of competition from weeds. The most significant
6-22
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problem with drawdown can be loss of use of the lake during the time it is drawn
down.
Drying and freezing can sharply reduce the abundance of benthic inver-
tebrates essential to fish diets. Also, an oxygen depletion in the remaining water
pool can occur, leading to a fishkill. Dissolved oxygen should be monitored in
small-volume systems, and an aerator should be installed if needed.

• COSTS. If the lake is controlled by a dam with drawdown capability, expen-
ditures will be minimal. Additional costs are associated with loss of use of the
lake.

Shading and Sediment Covers

The use of dyes in the water and coverings on the water surface to limit the light
available to plants and the application of plastic sheets over the sediments to
stop plant growth are prompted by the well-known facts that rooted plants re-
quire light and cannot grow through physical barriers. Applications of silt, sand,
clay, and gravel have also been used, although plants sooner or later can root in
them.
Sediment covering materials, such as polyethylene, polypropylene,
fiberglass, and nylon can be used in small areas such as dock spaces and swim-
ming beaches to completely terminate plant growth. Large areas are not often
treated because the costs of materials and application are high.

• EFFECTIVENESS. Case histories of the use of sediment covers are
described in detail in Cooke (1980), Cooke et al. (1986), and Cooke and Ken-
nedy (1981). Engel (1982) lists these advantages to their use:
1. Use is confined to a specific area.
2. Screens are out of sight and create no disturbance on shore.
3. They can be installed in areas where harvesters and spray boats cannot
reach.
4. No toxics are used.
5. They are easy to install over small areas.
And these disadvantages:
1. They do not correct the cause of the problem.
2. They are expensive.
3. They are difficult to apply over large areas or over obstructions.
4. They may slip on steep grades or float to the surface after trapping gases
beneath them.
5. They can be difficult to remove or relocate.
6. They may tear during application.
7. Some materials are degraded by sunlight.
8. A permit may be required.

Successful use is related to selection of materials and to the quality of the ap-
plication. The most effective materials are gas-permeable screens such as
Aquascreen (fiberglass), polypropylene, Dartek (nylon), and to a lesser extent,
common burlap. Polyethylene and synthetic rubber trap gases beneath them.
Proper application requires that the screens be placed flush with the sediment
surface and staked or securely anchored. This is difficult to accomplish over
heavy plant growth, making spring or during winter drawdown ideal times for ap-
6-23
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plication. Scuba divers are used for application in deep water, greatly increasing
costs. Depending upon siltation rate, sediment covers will accumulate deposits
on them, which allows plant fragments to root. Screens then must be removed
and cleaned. Details of application procedures are found in Cooke et al. (1986)
and Cooke and Kennedy (1981).
Surface shading has received little attention. Polyethylene sheets, floated on
the lake surface, were used by Mayhew and Runkel (1962) to shade weeds. They
found that 2-3 weeks of cover were sufficient to eliminate all species of
Potamogeton for the summer if the sheets were applied in spring before plants
grew to maturity. Coontail was also controlled but Chara was not. This proce-
dure may be a useful alternative to traditional methods of weed control in small
areas such as docks and beaches.
Dyes have been applied to small areas such as ponds to light-limit algae and
weeds.

• POTENTIAL NEGATIVE IMPACTS. Negative features of sediment covers
appear to be few. Benthic invertebrates may be eliminated (Engel, 1982), but dis-
solved oxygen depletions have not been a problem.

• COSTS. Table 6-3, modified from Cooke and Kennedy (1981), summarizes
costs of some sediment-covering materials. These costs do not include applica-
tion fees.

Table 6-3.—Characteristics of some sediment covering material (revised from
Cooke and Kennedy, 1988)
SPECIFIC APPLICATION GAS
MATERIAL GRAVITY COST DIFFICULTY PERMEABILITY COMMENTS
1. Black 0.95 $1,860/acre High Impermeable Poorchoiceof
Polyethylene materials-easily
dislodged;
"Balloons"

2. Polypropyl 0.90 $3,240/acre Low Permeable Effective
(Typar)

3. Fiberglass- 2.54 $8,700/acre Low Permeable Effective
PVC (Aqua-
screen)

4. Nylon >1.0 $3,240/acre Moderate Impermeable Effective if vented

(Dartek)

5. Burlap <1.0 $1,375/acre Moderate Permeable Effectiveupto
1 season; rots
Biological Controls
• PRINCIPLE. Significant improvement in our future ability to achieve lasting
control of nuisance aquatic vegetation in many areas of North America may
come from use of plant-eating or plant pathogenic biocontrol organisms, or from
a combination of current procedures such as harvesting, drawdown, and herb-
icides with these organisms. Biological control has the objective of achieving
long-term control of plants without introducing expensive machinery or toxic
chemicals.
6-24
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MODE OF ACTION
GRASS CARP (Ctenopharyngodon idella Val.): Grass carp are an exotic
fish (imported originally from Malaysia to the United States in 1962)
known to be voracious consumers of macrophytes. They have very high
growth rates (about 6 Ibs, or 2.5 kg, per year at the maximum rate; Smith
and Shireman, 1983). This combination of catholic diet and high growth
rate can produce control, or more likely, eradication of plants within
several seasons.
Grass carp do not consume aquatic plant species equally readily.
Generally, they avoid cattails, spatterdock, and water lily. The fish prefer
plant species that include elodea, pondweeds (Potamogeton spp.), and
hydrilla. Low stocking densities can produce selective grazing on the
preferred plant species while other less preferred species, including mil-
foil, may even increase. Overstocking, on the other hand, will produce
weed eradication. Feeding preferences are listed in Nail and Schardt
(1980), Van Dyke et al. (1984), and Cooke and Kennedy (1981).

INSECTS: Six insect species have been imported to the United States
under quarantine and have received U.S. Department of Agriculture ap-
proval for release to U.S. waters. These insects are confined to the waters
of Southern States and are specific to the control of alligatorweed and
water hyacinth. At present, neither exotic nor native insects are used
against Northern plants.
These six species have life histories that are specific to the host plants
and are therefore confined in their distribution to infested areas. They are
also limited in range by the cold weather of States north of Georgia-North
Carolina.
Their reproductive rates are slower than their target plants. Therefore,
control is slow, although it can be enhanced by integrated techniques
wherein plant densities are reduced at a site with harvesting or herbicides,
and insects are concentrated on the remaining plants.
EFFECTIVENESS
GRASS CARP: The use of grass carp is operational in several States (for
example, Florida, Texas, Arkansas), although they remain banned for
public and private use in many States. They are undergoing thorough
evaluation throughout the United States, especially the sterile triploid
variety. Most studies have found that the fish are exceptionally effective in
reducing or eliminating nuisance vegetation, although there have been
undesirable side effects. Two case histories illustrate their use.
Martyn et al. (1986) describe the introduction of diploid (able to
reproduce) grass carp into Lake Conroe, Texas, a water supply impound-
ment for Houston. Submersed weeds occupied about 44 percent of the
20,000 acres at maximum infestation. Most plants were hydrilla (Hydrilla
verticillata), although milfoil and coontail were also abundant. Between
September 1981 and September 1982, 270,000 grass carp, 8 inches or
longer, were introduced. By October 1983, all submersed plants were
gone. Associated with this eradication was an increase in algae, a
decrease in transparency, and an increase in open-water fish species as-
sociated with plankton. Fish associated with weed beds declined.
Van Dyke et al. (1984) have reported on the effects of diploid grass
carp stocking in three central Florida lakes and one reservoir. Hydrilla was
eliminated for 6 years and may have been eradicated from the lakes. Few
rooted plants remain. Illinois pondweed (P. illinoiensis) was eliminated
6-25
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from the reservoir, and milfoil was greatly reduced. Control in all four sites
was slowly achieved but has been long-lasting. Eurasian watermilfoil has
returned to the reservoir, apparently because carp escaped.
Grass carp have not been successful weed management agents in the
sense that small numbers could be stocked to achieve a partial elimina-
tion of plants. Shireman et al. (1983) attempted to do this in Lake Pearl,
Florida, by stocking carp at low densities and using some herbicides on
an infestation of hydrilla. Carp were stocked at increasing rates over a 2-
year period while herbicide additions continued. After 2 years, a carp den-
sity was finally reached that had an impact on the plants, and then
eradication occurred. Stocking rates appear to vary geographically, with
the type, diversity, and coverage of plants, and with the management
goal. A detailed discussion of stocking rates and food preferences is
found in Cooke and Kennedy (1988), and State fisheries personnel can be
an excellent source of information. Lake homeowners and managers are
strongly advised not to stock a lake unless competent technical advice
about your specific lake has been obtained. State fisheries personnel
should be contacted prior to stocking because this practice is not legal in
all States (see Table 6-4).
Further descriptions of case histories can be found in Cooke et al.
(1986) and Cooke and Kennedy (1988).

Table 6-4.—State regulations on possession and use of grass carp (modified from
Allen and Wattendorf, 1987)

A. Diploid (able to reproduce) and Triploid (sterile) permitted
Alabama Hawaii Kansas Oklahoma
Alaska Iowa Mississippi New Hampshire
Arkansas Idaho Missouri Tennessee

B. Only 100% Triploids permitted
California Illinois New Jersey South Carolina
Colorado Kentucky New Mexico South Dakota
Florida Montana North Carolina Virginia
Georgia Nebraska Ohio West Virginia

C. 100% Triploids permitted for research only
NewYork Louisiana Oregon Wyoming

D. Grass Carp prohibited
Arizona Maryland North Dakota Utah
Connecticut Massachusetts Pennsylvania Vermont
Delaware Michigan Rhode Island Washington
Indiana Minnesota Texas Wisconsin
Maine Nevada

INSECTS: Insects have proven to be highly effective controls of alligator-
weed and water hyacinth. For example, Sanders and Theriot (1986) report
that the water hyacinth weevil (Neochetina eichhorniae) has been respon-
sible for at least a 50 percent decrease in the water hyacinth distribution in
Louisiana since 1974. Insect control has been particularly effective when
combined with another plant management technique. Two case histories
illustrate this point.
Center and Durden (1986) studied the effect of the water hyacinth
weevil in a Florida canal. When a canal section was harvested at the peak
of the growing season, both water hyacinths and weevils were severely
reduced. Subsequent plant growth was much greater than the weevil
population, and control was greatly delayed. Another section was
sprayed with 2,4-D at season's end, allowing plants and weevils to
6-26
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recover simultaneously. Insect control occurred more rapidly. Chemical
or mechanical control, along with insects, will be more effective if done in
early fall or winter to minimize interference with the insect.
Haag (1986) studied a Florida pond that was 100 percent covered with
water hyacinth. Weevils (N. eichhornia and N. bruchi) were present in
small numbers. About 20 percent of the pond was isolated with a barrier
while the rest was sprayed with 2,4-D in monthly increments of 25 percent
of the remaining pond area. Weevil density slowly increased in the iso-
lated area and by the following year exerted 100 percent control of water
hyacinth in the entire pond. Eradication allowed alligatorweed to invade,
but its spread was checked by the alligatorweed flea beetle, Agasicles
hygrophila.
This work supports the conclusion that weed eradication with herb-
icides, a common strategy, will also eliminate the insects and allow a
prompt return of the weeds. By leaving a reservoir of weeds and by "herd-
ing" the insects to it, sufficient insect density is achieved to produce
longer term weed control.
• POTENTIAL NEGATIVE IMPACTS
GRASS CARP: Grass carp can produce a major change in the structure
of a lake or reservoir, particularly when macrophytes are eradicated.
Eradication of plants is almost certain if overstocking occurs. Increases in
nutrient concentrations, blue-green algal blooms, turbidity, and changes
in fish communities have been commonly reported (Cooke et al. 1986;
Cooke and Kennedy, 1988). The long-term consequences of plant
eradication are very poorly understood.
The introduction of grass carp into hydrologically open systems
(reservoirs, man-made ponds) has raised important questions about es-
cape and reproduction in habitats where vegetation is desirable. While
environmental requirements for successful reproduction are stringent and
were once believed to be an adequate barrier to their multiplication in
North American waters, grass carp have apparently reproduced in the
United States. More recently, sterile triploid grass carp have been
developed and are the only type of grass carp permitted in many States.
While their reproduction is not possible, their escape in large numbers
from a hydrologically open system, such as a reservoir, can still pose a
significant threat to a downstream habitat where aquatic vegetation is
desired.
INSECTS: Significant negative environmental impacts of insects have not
been observed, except for changes in aquatic habitats associated with
macrophyte elimination.

• COSTS. Cost comparisons for biological controls are generally not yet avail-
able for biological controls, but these methods do appear to be far less costly
than the traditional alternatives of chemical or mechanical treatments. These lat-
ter techniques, in addition to the costs of equipment, materials, labor, and in-
surance, must be reapplied frequently. Shireman (1982) and Shireman et al
(1985) report that $117,232 had been spent on endothal for the temporary con-
trol of hydrilla in Lake Baldwin, Florida. The hydrilla problem was eliminated with
grass carp at a cost of $8,499 ($43 per acre). Unlike herbicide or harvesting
treatments, the grass carp exert control for many years with one treatment, so
that costs are amortized. Byway of comparison, harvesting costs in Florida can
easily be $1,000 per acre while chemical costs in Florida range from $200 to 400
6-27
-------
per acre (Cooke and Kennedy, 1988). Harvesting and herbicide costs in Nor-
thern climates are essentially the same. Also, Shireman (1982) points out that in
1977, the cost of chemical treatment of 37,000 acres of hydrilla in Florida was
$9.1 million; the cost of grass carp to provide long-term control would have been
about $1.71 million if stocked at a density of 14 fish of 8 inches or longer per
acre.
Macrophytes/Techniques with

Shorter-Term Effectiveness

Harvesting

• PRINCIPLE. Harvesting is a procedure to cut and remove nuisance rooted
plants and associated filamentous algae. Unlike herbicide applications where
plants are left in the lake to die, decompose, and release nutrients and organic
matter, harvesters may have some restorative value in lakes with dense infesta-
tions and low external loading because these materials are removed. Some
potable water supply systems use them to reduce the release of organics,
which, when chlorinated in the treatment plant, produce potentially carcinogenic
molecules such as trihalomethanes (THM's). Harvesters can clear an area of
vegetation without the posttreatment waiting period associated with herbicides
and without significant danger to nontarget species.

• MODE OF ACTION. The typical harvester is a highly maneuverable, low-draft
barge designed with one horizontal and two vertical cutter bars, a conveyor to
remove cut plants to a hold on the machine, and another conveyor to rapidly un-
load plants (Fig. 6-8). Some manufacturers sell shore conveyor units to assist
loading from harvester to truck and high-speed barges to carry cut plants from
the harvester to shore. Harvesters vary in size and storage capacity from about
200 ft (6 m3) of cut vegetation to 800 ft3 (23 m3). Cutting rates range from about
0.2 to 0.6 acres per hour, depending on machine size. The barge itself can be
very useful with other like improvement procedures, including applying alum.
Primary power source
2 cylinder deutz diesel
Operator console

Cutting bed rams
Vertical sickle bar
cutters
Figure 6-8.-The Aquamarine Corporation's H650 harvester. (Courtesy of the Aquamarine
Corporation).
6-28
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Weed disposal is usually not a problem, in part because lakeshore residents
and farmers often will use the weeds as mulch and fertilizer. Also, since aquatic
plants are more than 90 percent water, their dry bulk is comparatively small.

• EFFECTIVENESS. Most harvesting operations are successful in producing
at least temporary relief from nuisance plants and in removing organic matter
and nutrients without the addition of a potentially deleterious substance. Plant
regrowth can be very rapid (days or weeks), especially in Southern waters
where midsummer growth rates of water hyacinth can exceed the rate at which
they can be harvested. Several case histories illustrate this.
A bay of LaDue Reservoir (Geauga Co., Ohio) was harvested in July 1982,
using the traditional method in which the operator treats the weed bed like a
residential lawn and simply mows the area. Stumps of Eurasian watermilfoil
plants, about 0.5-3 inches in height, were left, and complete regrowth occurred
in 21 days. In contrast, Conyers and Cooke (1983) and Cooke and Carlson
(1986) have found that the slower method of lowering the cutter blade about 1
inch into the soft lake mud will produce season-long control of milfoil by tearing
out roots. Of course this cutting technique is of little value where sediments are
very stiff and in deeper water where the length of the cutter bar (usually 5-6 feet)
cannot reach the mud. When only plant tops are cut, regrowth may be rapid.
There is evidence of a carry-over effect (less growth in the subsequent year),
especially if an area has had multiple harvests in one season.
Some weed species are more sensitive to harvesting than others. Nicholson
(1981) has suggested that harvesting was responsible for spreading milfoil in
Chautauqua Lake, NY, because the harvester spreads fragments of plants from
which new growths can begin. On the other hand, he considers Potamogeton
spp., another nuisance plant, to be far more susceptible because these species
emphasize sexual reproduction and regenerate poorly from fragments. Harvest-
ing therefore could mean that milfoil could replace Potamogeton.
There are few data on the actual restorative effects of harvesting, in the sense
of removing significant amounts of nutrients or in reducing the release of
nutrients and organic matter to the water column. If nutrient income is moderate
and weed density is high, as much as 40-60 percent of net annual phosphorus
loading could be removed with intense harvesting. This would be a significant
nutrient removal in many cases. Milfoil may be a large contributor of phosphorus
to the water column throughout the summer (Smith and Adams, 1986), strongly
suggesting that removing this plant through harvesting could curb this source of
nutrients to algae. An herbicide application would leave the plants to decom-
pose and release nutrients and organic material to the water column. On the
other hand, harvesting itself can increase water column phosphorus concentra-
tion either through mechanical disturbance of sediments or by enhancing condi-
tions for phosphorus release from sediments (Cooke and Carlson, 1986).
Effective use of a harvester to manage aquatic plants and to minimize
regrowth during the season includes the purchase of a machine of sufficient size
to handle the affected areas, the use of proper cutting techniques, and the siting
of disposal areas nearby the areas to be harvested.

• POTENTIAL NEGATIVE IMPACTS. Cooke et al. (1986) and Cooke and Ken-
nedy (1988) have listed some of the possible negative effects of harvesting:
1. Cutting and removing vegetation can be energy- and labor-intensive and
therefore costly.
2. Only relatively small areas can be treated per unit time, which may create
lake user dissatisfaction.
3. A high capital outlay for equipment is required.
6-29
-------
4. Plants may fragment and spread the infestation.
5. Small fish may be removed.
6. Operating depths are limited.
7. Favorable weather is required.
8. Machine breakdown can be frequent, especially if an undersized piece of
equipment is purchased.

• COSTS. Harvesting costs in the Midwest have ranged from $135 to $300 per
acre when costs from extreme situations are omitted (Table 6-5), making the
technique somewhat less costly than herbicide treatments. Costs in Florida have
exceeded $1,000 per acre. Costs of a particular project will relate to machine
cost, labor, fuel, insurance, disposal charges, and the amount of downtime. Es-
timates of manpower time and costs can be obtained from the HARVEST model
developed by the U.S. Army Corps of Engineers (Hutto and Sabol, 1986), which
runs on a personal computer. The program is available from Program Manager,
Aquatic Plant Control Research Program, Environmental Laboratory, Waterways
Experiment Station, Vicksburg, MS 39180.

Table 6-5.—Cost comparisons, in 1987 dollars, of three symptomatic treatments
for nuisance aquatic weeds (Florida data for grass carp)
PROCEDURE COSTRANGE
Harvesting
Midwest $135-300 per acre
Florida $300-5,000 per acre

Herbicides
Midwest $200-400 per acre
Florida $200-400 per acre

Grass Carp* $85 per acre
(cost is also amortized due to
long-term effectiveness)
'12 inch or greater fish, stocked at 14-20 per acre
Herbicides

• PRINCIPLE AND MODE OF ACTION. Poisoning nuisance aquatic weeds is
perhaps the oldest and most widely used method to attempt their management.
Few alternatives to herbicides existed until recently. The pesticide industry has
grown and has been more carefully regulated so that some of the most
dangerous and toxic herbicides, such as sodium arsenite, have been replaced
with chemicals that have much lower toxicity to nontarget biota and leave
degradable residues.
An herbicide treatment can be an effective short-term management proce-
dure to produce a rapid reduction in vegetation for periods of weeks to months.
Pesticide use cannot be equated with lake restoration, since causes of the weed
problem are not addressed nor are nutrients or organic matter removed. Plants
are left to die and decompose. New plants will shortly regrow, sometimes to den-
sities greater than before.
6-30
-------
The use of herbicides remains controversial and emotion-charged, in part be-
cause they have been promoted as, and confused with, restoration procedures,
and in part because their positive and negative features have been poorly under-
stood by both proponents and opponents. For example, as carefully pointed out
by Shireman et al. (1982), herbicide treatments are presently the only means of
opening the vast acreage of water infested with the exotic water hyacinth (Eich-
horniae crassipes) in Florida and other Southeastern States. This is a case in
which chemicals for management are a necessity until some other more long-
term control can be established. Their broad-scale use in other climates, often
for the purpose of seasonal eradication of weeds, is more controversial, espe-
cially since equally cost-effective alternatives have smaller environmental im-
pacts. Many opponents of herbicides fear their effects on fish and fish-food
organisms. Some chemicals can be toxic at high doses, but most have low
toxicity to aquatic organisms. The impacts of herbicides on humans is poorly
understood, and there is almost no information on the long-term ecological con-
sequences of their use.
Lake managers who choose herbicidal chemicals need to exercise all proper
precautions. As shown in Table 6-6, some chemicals are specific to certain
species, and therefore a careful identification of the nuisance plants is needed.
Users should follow the herbicide label directions exactly, use only an herbicide
registered by the U.S. EPA for aquatic use, wear protective gear during applica-
tion, and be certain to protect desirable plants. Most States require applicators
to be licensed and to have adequate insurance. Among the important factors to
be considered before adopting a management program with herbicides are the
following questions:
1. What is the acreage and volume of the area(s) to be treated? Proper
dosage is based upon these facts.
2. What plant species are to be controlled? This will determine the herbicide
and dose to be used.
3. What will the long-term costs of this decision be? Herbicides must be reap-
plied annually or in some cases, 2-3 times per season.
4. How is this waterbody used? Many herbicides have restrictions (days) on
water use, following application.
5. Is the applicator licensed and insured, and has a permit been obtained
from the appropriate regulatory body?
There are several useful and well-written reference manuals to facilitate plant
identification and the determination of the proper chemical and its dose. These
include (1) Aquatic Weeds. 1979. Fisheries Bulletin No. 4, Department of Con-
servation, Springfield, IL 62706; (2) Submersed Aquatic Weeds and Algae
Guide. 1984. Pennwalt Corp., Three Parkway, Philadelphia, PA 19102; and (3)
How fo Identify and Control Water Weeds and Algae. 1979. Appl ied Biochemists,
Inc., Mequon, Wl 53902.
• EFFECTIVENESS. Table 6-6 lists some aquatic weeds and the herbicides
known to control them. The following paragraphs briefly describe each com-
monly used herbicide.
Diquat. The effectiveness of diquat is inactivated in turbid water due to its
sorption to particles. It does not persist in the water but can remain toxic in lake
sediments for months. Many users combine it with copper sulfate, producing a
potent, broad-scale herbicide-algicide. The reader is cautioned to note the toxic
features of copper, described in an earlier section.
Endothall. Endothall is sold in several formulations: liquid (Aquathol K),
granular dipotassium salt (Aquathol), and the di (N, N-dimethylalkylanine) salt
6-31
-------
Table 6-6.—Common aquatic weed species and their responses to herbicides
(adapted from Nichols, 1986)

EMERGENTSPECIES
Allernantherca philoxeroides
(alhgatorweed)
Dianthera americana
(water willow)
Glyceria borealis
(mannagrass)
Phragmites spp (reed)
Ranunculus spp (buttercup)
Sagittaria sp (arrowhead)
Scirpus spp (bulrush)
Typha spp (cattail)
FLOATING SPECIES
Brasen/a schreberi
(watershield)
Eichhorniae crassipes
(water hyacinth)
Lemna minor (duckweed)
Nelumbo lutea
(American lotus)
Nuphar spp (cowlily)
Nymphaea spp (waterlily)
SUBMERGED SPECIES
Ceratophyllum demersum
(coontail)
Chara spp (stonewort)
Elodea spp (elodea)
Hydrilla verticillata
(hydrilla)
Myriophyllum spicatum
(milfoil)
Najas flexilis (naiad)
Najas guadalupensis
(southern naiad)
Potamogeton amplifolius
(large-leaf pondweed)
P. crispus
(curly-leaf pondweed)
P. diversifolius (waterthread)
P. natans
(floating leaf pondweed)
P. pectinatus
(sago pondweed)
P. illinoiensis
(Illinois pondweed)
DIQUAT

YES

NO
NO
YES

YES1

YES
NO

NO
NO

YES

NO2
YES

YES

YES
YES

?
YES

NO
YES

YES

ENDOTHAL

NO
NO
NO

NO
NO

YES

NO2
?

?
?

YES
YES

YES

2,4-D

YES

YES
YES
YES
?

YES

NO
7

YES
?

YES

NO2
NO

YES

NO
NO

NO
YES

GLYPHOSATE
(RODEO)

YES

YES
YES

NO2 NO2

FLURIDONE
(SONAR)

YES

YES
YES
9

YES

YES
YES

YES

YES
YES

YES

YES
YES

YES

YES = Controlled
BLANK - Information unavailable
NO = Not Controlled
9 - Questionable Control
1 plus chelated copper sulfate 2 controlled by copper sulfate
Sources Anonymous, 1979, Arnold, 1979, Gangstad, 1986, McCowen et al, 1979, Nichols, 1986, Pennwalt Corp , 1984,

Schmitz, 1986
6-32
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(Hydrothal) in liquid and granular forms. Effectiveness can range from weeks to
months. The potassium salt forms have been shown to persist in the water for 2
to 46 days.
2,4-D. 2,4-D is sold in liquid or granular forms as sodium and potassium salts,
as ammonia or amine salts, and as an ester. Doses of 18-36 Ibs per acre are
usual for submersed weeds, most often of the dimethylamine (DMA) salt or the
butoxyethanolester (BEE). This herbicide is particularly effective against
Eurasian watermilfoil (granular BEE applied to roots early in the season) and
against water hyacinth (a foliage spray). 2,4-D has a short persistence in the
water but can be detected in the mud for months.
Glyphosate. This herbicide, known as Rodeo, is effective against floating
leaves and emergent aquatic plants but not against submersed species.
Fluridone. Fluridone (Sonar) is sold in liquid and pellet formulations as an
herbicide for emersed and submersed weeds. It is a persistent compound and
will not exert effect until 7-10 days after application. Control may be evident for
an entire season. Sediments may remain toxic to plants for more than a year.
Label registration restrictions on water use following treatment are very im-
portant and should be followed carefully regardless of the herbicide chosen.
Each State has its own regulations as well.
• POTENTIAL NEGATIVE IMPACTS. Many, but not all, nontarget aquatic or-
ganisms appear to have high tolerances to the herbicides just discussed. Diquat
is a notable exception because of its toxicity to some Crustacea, a staple of fish
diets.
The primary environmental impacts include release of nutrients to the water
column and consumption of dissolved oxygen during plant decomposition.
Algal blooms, dissolved oxygen depletions, and nutrient release from sediments
can follow a treatment. Another significant problem is that a species unaffected
by the herbicide may replace the target species. Chara and Potamogeton often
invade a treated area. When a target weed is replaced by an algal bloom or a
resistant weed, another chemical may have to be used, making herbicide treat-
ment even more expensive.
Shireman et al. (1982) caution that these lake or pond characteristics almost
invariably produce water quality changes following treatment with an herbicide
for weed control:
1. High water temperature
2. High plant biomass to be controlled
3. Shallow, nutrient-rich water
4. High percentage of the lake's area to be treated
5. Closed or nonflowing habitat
Competent applicators will be cautious in treating a lake with these condi-
tions.
There has been a long-standing debate over the effects of 2,4-D on humans.
An apparent resolution has been published that establishes that men exposed to
2,4-D and/or 2,4,5-T for more than 20 days per year have a sixfold increased risk
of non-Hodgkins' lymphoma (Hoar et al. 1986).
• COSTS. Herbicide treatments are costly for what they accomplish. They
produce no restorative benefit, show no carry-over of effectiveness to the follow-
ing season, and may require several applications per year. The short-term
benefit-cost ratio can be desirably high, but the long-term benefit-cost ratio is
likely to be very low.
6-33
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Their ranges of per-acre costs for harvesting and herbicide treatments are
similar, but grass carp are significantly less than either (Table 6-5). It should be
recalled, however, that harvesters remove nutrients and organic matter (a poten-
tial source of THM precursors and of dissolved-oxygen consumption) and can
have a carry-over effect to subsequent seasons.
One study of harvesting and herbicide (Diquat and copper sulfate) costs
showed that harvesting was more expensive only in the initial year when the
machinery was purchased. In the following years, maintenance, operation, in-
surance, and weed disposal costs were lower than costs for chemicals alone.
Harvesting, in this case history, cost $115 per acre and herbicides cost $266 per
acre, so that over a 5-year period, not including herbicide price inflation or ap-
plicator fees, the use of chemicals would have been 2.6 times more expensive
than harvesting and without the benefits of nutrient and organic matter removal
(Conyers and Cooke, 1983)
Shireman (1982) has compared the costs of chemical and biological (grass
carp) control of hydrilla in Florida. A chemical treatment of 37,000 acres in 1977
cost $9.1 million, whereas a grass carp introduction would have cost $1.71 mil-
lion. Of course the grass carp exert control slowly while herbicides provide
prompt, though short-term relief.
Table 6-5 provides regional cost ranges which could be expected for her-
bicides. Variations in costs are brought about by size of area to be treated, den-
sity of the infestation, species, and problems unique to a particular lake.
Macrophytes/Summary of

Restoration and Management

Techniques
Table 6-7 is a summary of the procedures described in this section. Qualitative
evaluations about short- and long-term effectiveness, costs, and potential for
negative side effects are presented. These judgments are the consensus of 12
lake and reservoir restoration experts.

Table 6-7.—Comparison of lake restoration and management techniques for
control of nuisance aquatic weeds
TREATMENT SHORT/TERM
ONE APPLICATION EFFECT
Sediment Removal
Drawdown
Sediment Covers
Grass Carp
Insects
Harvesting
Herbicides
E
G
E
P
P
E
E
LONG/TERM
EFFECT
E
F
F
E
G
F
P
COST
P
E
P
E
E
F
F
CHANCE OF
NEGATIVE EFFECTS
F
G
E
F-G
E
F-G
P
E - Excellent F = Fair G = Good P = Poor
6-34
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Problem IV: Eutrophic

Drinking Water Reservoirs

Nature of the Problem

Those who drink water from surface water supply reservoirs often detect un-
pleasant tastes, odors, and color. They may be unaware of more serious
problems that are unknown to the user, but are of concern to potable water
treatment plant managers, and State and Federal EPA officials: the presence of
potentially toxic materials in finished water. Toxic material can enter drinking
water supplies directly by runoff from the land (for example, herbicides). They
can also be created in the finishing process when treatment plant chemicals in-
teract with organic molecules in the raw water to form potentially dangerous
compounds such as trihalomethanes, or THM's.
Many of the problems in potable water treatment are caused by eutrophic
conditions in the water supply reservoir. Poor taste and odor are associated with
algal blooms. Some of these algae, the blue-greens, produce toxins lethal to
domestic animals and may be linked to certain summer illnesses in humans.
Colored water is usually caused by a high concentration of iron and man-
ganese in the raw water. This occurs when the raw water intake is deep and
withdraws oxygen-free hypolimnetic water. THM's are a class of organic
molecules — chloroform is in this class — that are produced through an interac-
tion between the disinfectant (chlorine) added to raw water to kill microbes, and
certain organic molecules in the raw water. The organic molecules come from
the watershed, primarily in the form of plant decay products, and from weeds
and algae in the reservoir. THM's are believed to be carcinogenic. The U.S. EPA
has set an upper average amount (0.1 ppm), past which finished water should
not go.
Other eutrophication-related problems in water supply systems include a
gradual loss of water storage as silt deposits increase, rapidly escalating costs
connected with increased chemical use to clean the raw water, and such in-
plant problems as clogged filters.
Water Supply Reservoir Management

The traditional approach to improving drinking water quality is to upgrade the in-
plant treatments. Sometimes this is effective, particularly where the water supply
is in good to very good condition. In other cases, the modifications of the plant
required to remove organics are exorbitant. Granulated active carbon (GAC) is
the most likely process to be added, and this might cost a modest sized city $20
million in capital costs plus $1 million annually for operation.
The better the incoming water, the less it will cost to finish. Ultimately, water-
shed and reservoir protection and restoration may be less costly than extensive
in-plant modifications. As already pointed out, however, reservoirs are very dif-
ficult to protect because their drainage basins are often large relative to reservoir
area and usually include several political and economic units. The city or con-
trolling authority may have to embark on a long-term effort to buy land, en-
courage or subsidize wastewater treatment plant upgrades, and help land users
to employ modern agricultural practices.
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One alternative or an addition to drainage basin management is the use of
chemicals such as alum in the river to strip phosphorus from the water before it
enters the reservoir. This can involve a detention basin, or the addition of a
chemical to the stream (Cooke and Carlson, 1986).
Another option is to divert river water into a smaller, square-sided, weedless
basin, where silt deposition and additions of flocculent could occur. Wahnbach
Reservoir, an example of this, was described in Chapter 4. The basin can be pe-
riodically drained and dredged.
Water supply reservoirs near highways, railroads, and within industrial areas
are vulnerable to accidental spills of toxic materials. Few are protected or
prepared for this. The side basin described above, built large enough to hold a 3-
5 day supply, could also serve as an emergency raw water supply.
Theoretically, most of the techniques described earlier in this chapter could
be used to improve water quality, or to actually restore the reservoir after poor
quality waters are diverted. In practice, however, restoration techniques are not
easily applied to reservoirs because of their size and the difficulty of reducing
loadings. The following paragraphs list drinking water quality problems and pos-
sible in-reservoir solutions.

Color

Iron and manganese appear in oxygen-free raw water. Two solutions are com-
mon: using a hypolimnetic aerator or elevating the intake from the hypolimnion
to the epilimnion. Drawing water from the epilimnion can introduce taste and
odor, and the aerator could destratify a shallow reservoir, triggering an algal
bloom.

Taste and Odor

Algal blooms, particularly blue-green algae, not only can impart an unacceptable
taste and odor but can also increase the demand for treatment chemicals and
decrease filter runs. There are few solutions if nutrient diversion is not adequate.
Artificial circulation could reduce productivity of algae in deep reservoirs, but is
unlikely to be effective in shallow ones. Sediment removal and especially phos-
phorus inactivation, both procedures to curtail sediment nutrient release, will be
eventually overwhelmed by high loading, but offer the possibility of improvement
for several years. Copper sulfate, an algicide, can be used for short-term relief,
but applications are often followed by more severe blooms and by release of
substances that add to THM production.

Loss of Storage Capacity

This problem can only be solved through silt removal and curtailment of silt in-
come. A stringent permitting process may be imposed by the U.S. Army Corps
of Engineers if dredging is chosen because the reservoir is a potable water sup-
ply.

Trihalomethane Production

A search for sources of organic THM precursor molecules in the drainage basin
must be undertaken, followed by appropriate land management to curtail their
generation. Marshes are known to be important sources. A substantial fraction of
the organics can come from sediments, weeds, and algae, strongly suggesting
that in-reservoir management of these plants could produce a significant
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decrease in THM production. Harvesting would be an effective procedure.
Another possibility is to add clean well water to the raw water at the intake in
order to dilute it.
Problem V: Fish Management

Nature of the Problem

Most lakes and reservoirs are used to some extent for fishing, and many (ac-
cording to fishermen) are considered unsatisfactory. Problems with fishing
usually fall into these categories:
1. Conflicts between users - including high fishing pressure
2. Overabundance and population imbalances - especially of "stunted"
fish or undesirable species
3. Survival - including poor reproduction and die-off of desirable species
User conflicts are not trivial. Chapter 9 addresses the problem of regulating
these conflicts.
Fish production is directly related to lake fertility. Unfortunately, the nutrient-
rich water that favors high fish biomass may also promote algal blooms repug-
nant to swimmers. High fishing pressure can both degrade fishing quality and
limit the use of the lake for other purposes, including high-speed boating. Fisher-
men often complain that a lake is "fished out" or has too many little fish or too
many "trash" species. This leads to vocal demands for restocking, a process
that is likely to have only short term benefits.
Improvement of a lake or reservoir for fishing requires fish management. Ben-
nett (1970), citing Leopold (1933), defines fish management as "the art and
science of producing sustained crops of wild fish for recreational and commer-
cial uses." Competent programs include a diagnostic study and then implemen-
tation of management options that are ecologically sound and within financial
constraints.
Diagnosis and Management

Just as with lake restoration, a diagnosis of the condition of the fish community
is the first step in a fish management program. For most situations, this involves
fish sampling to provide an assessment of the lake's present fish population.
Various sampling methodologies and strategies are available, the specific ap-
proach being dependent upon the region in the country where the lake is lo-
cated, the type of fish to be sampled, the purpose of the sampling, and the
characteristics of the particular lake. Before attempting to diagnose fishery con-
dition, a consultation with State or local fisheries professionals is strongly
recommended.
Fisheries management, as described earlier, is often an integral part of a lake
restoration plan. It is important to remember that lake ecosystems are complex
and highly interconnected. Fishermen may urge a lake manager to stock
predators, such as walleye, muskie, or bass to improve fishing or even a lake's
water quality. However, corrective stocking frequently fails. Often the lake is at
or near its productive capacity. Game fish fry stocked in a poor quality lake may
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not survive the many sources of mortality, including intense predation. The
stocking of significant numbers of older fish is expensive and the animals are
more difficult to obtain. High fishing pressure can quickly reduce their numbers
once stocked. Similarly, some lake managers have heeded advice to stock
forage species, such as shad, only to discover later that shad grazing on
zooplankton was sufficient to permit algal bloom (see the section on biological
controls in this chapter) and their reproduction exceeded predation on them.
There are several valuable sources of information about fish management.
Each State has a fisheries unit that can provide important guidelines specific to
that geographic area.
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CHAPTER 7
Hypothetical Case Study
-------
CHAPTER 7
HYPOTHETICAL CASE STUDY
Purpose of Case Study
Armed with all the explanations, guidance, instructions, and information in the
preceding chapters, could a lake user or lake association group "do lake
management?" The answer is yes; these associations are the driving force be-
hind the many lake restoration and management programs in the United States.
They may hire experts, but the burden of making the critical decisions and bear-
ing the responsibility for organizing and sustaining a restoration program is typi-
cally borne at the grass roots level. The hypothetical case study in this chapter
illustrates how a lake management or restoration program is carried out. This
case study integrates the information and material from the previous sections,
including problem definition, in-lake restoration techniques, watershed manage-
ment, data analysis, and the evaluation and selection of management alterna-
tives.
Lynn Lake — a hypothetical waterbody — suffers from excessive algae,
aquatic weeds, and siltation. Like most lakes that are managed and restored to
good condition by involved citizens, Lynn Lake is extremely popular locally. It is
not one of the largest or most important lakes in the State, or even well-known
outside the State. Restoration will take major effort and a considerable dedica-
tion of local citizens — but it can be done. The rest of the case study will
demonstrate how this is accomplished.
Lynn Lake - A Case Study
Lynn Lake is located completely in Kent County. A county park is located on the
western side of the lake, but the entire perimeter is accessible to the public. The
lake is used heavily for fishing, swimming, and boating; well-used jogging and
walking trails circle the lake. Swimming is often prohibited because of high levels
of algae and bacteria. Boating is impaired by macrophytes that cover 50 percent
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of the lake. Siltation of the inlet areas of the lake has also limited the use of these
areas for boating. Lynn Lake (Fig. 7-1) has two major tributaries: Kimmel Creek
and Tag Run. The City of Middletown is located on Kimmel Creek and has a
secondary wastewater treatment plant that discharges to the creek. Upstream of
Middletown is Blue Ridge, a 200-unit subdivision that is presently under con-
struction. Tag Run, the other tributary, is surrounded mostly by wetlands, ponds,
and undeveloped land.
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Problem Definition
Because of concern over the declining condition of the lake, the county col-
lected several water samples and analyzed them for nutrients (phosphorus and
nitrogen) and algae. The results indicated that the lake has high levels of phos-
phorus and nuisance blue-green algae. County officials decided to conduct a
survey over the July 4th weekend to ask residents what problems they had ob-
served and to gage the degree of concern and potential support for restoring the
lake to better condition. The survey questions shown in Table 7-1, were asked to
residents who used the lake over the holiday weekend. Interest in the lake
proved high because 70 percent of the households in the Lynn Lake basin

Table 7-1.—Public Opinion Questionnaire.

1 How often do you visit Lynn Lake?
2. How far do you travel to visit Lynn Lake?_
3. When you visit Lynn Lake, what activities do you participate in?
D Picknicking D Jogging D Swimming
D Walking D Boating D Other
4. Since Lynn Lake appears to be suffering from excessive algae, aquatic weeds and
siltation, do you support a lake restoration program that would include a study of the
lake and the implementation of a program to eliminate the lake problems?
D Yes D No H Undecided

1. How often do you visit Lynn Lake?
TIME PERCENT
Daily 3
Weekly 32
Monthly 56
Annually 9

2. How far do you travel to visit Lynn Lake?
MILES PERCENT
0-12 29
2-5 33
5-10 36
>10 2

3. When you visit Lynn Lake, what activities do you participate in?
78 Picknicking 32 Jogging 2_ Swimming
59 Walking 61 Boating Other Model Boats: 1
Necking: 1
4. Since Lynn Lake appears to be suffering from excessive algae, aquatic weeds and
siltation, do you support a lake restoration program that would include a study of the
lake and the implementation of a program to eliminate the lake problems?
100% Yes 0% No 0% Undecided

5. Restoration of Lynn Lake will require the expenditure of County funds. Partial funding of
the restoration program may be obtained from a State or Federal grant. Realizing this,
do you still support the implementation of a lake restoration program for Lynn Lake?
98 Yes, only if State or Federal funds are available to offset the cost of the program
94 Yes, even if only County funds are used
2 No 0 Undecided
runoff from new construction (especially the Blue Ridge Development), erosion
from farmland, and nutrients leaching from failing septic systems. They also sug-
gested that erosion from roadway construction and maintenance being per-
formed by the State Highway Department was contributing to the sedimentation
problem. Several lake users indicated that the shoreline was sloughing in a few
areas. Green algal scums and weeds, however, were universally agreed to be
the major problem.
At the end of the meeting, the county formally formed a special committee to
investigate the possibility of restoring Lynn Lake. The committee was made up of
the County Engineer, the Director of the County Planning Department, the Direc-
tor of Middleton Public Works, and four interested lake users. The County Com-
missioners also approved a motion to hire a consultant if help could not be
found through the county staff or State office first. It was agreed that the special
committee would seek out recommendations of firms capable of helping with the
restoration project, review qualifications, and recommend a consultant.
In the next month, members of the special committee sought information and
sources of help in lake restoration. They asked the State Water Control Board
and the State Health Department whether any programs existed that could be
used to study or restore Lynn Lake. Since no State program or funding dedi-
cated to lake preservation or management existed, the committee asked for
general information on lake restoration and as much guidance as possible. A
staff member of the State Water Control Board was able to give them names of
lake associations and municipalities in the State that were involved in lake res-
toration. The committee contacted them to find out how they had carried out
their projects and who they might recommend as a consultant. One member of
the special committee was also a member of the North American Lake Manage-
ment Society (NALMS). The special committee called the NALMS office in
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Washington, DC, and asked for help. They ordered a booklet on lake restoration
and explained the types of problems Lynn Lake was having. The NALMS office
sent a list of consultants in Lynn Lake's area who specialized in lake restoration
and a list of NALMS members who had agreed to help lake associations and
municipalities with general questions such as how to find help and how to estab-
lish a public information program to support the work.
The committee contacted lake associations and municipalities in the State
that had begun restoration projects and asked them who they had used to carry
out the work, how they had paid for it, what to expect, what the consultant had
done for them, how much the program had cost, whether it had been effective
and whether they were satisfied with the results.
At the next meeting, the special committee reported its findings. The commit-
tee voted to initiate a lake restoration program that would include the followino
activities: a
1. Forming a Lake Restoration Advisory Committee
2. Selecting a consultant to perform the lake study, evaluate the management
alternatives, assist in implementing the restoration program, and help the as-
sociation find funding to support the work and prepare any grant application
packages
3. Developing a detailed work plan
4. Submitting a grant application to the EPA for a Phase I Diagnos-
tic/Feasibility Study
5_ Performing a study of Lynn Lake that would quantify the problems and
problem sources and result in the development of a comprehensive lake and
watershed management program
6. Submitting a grant application to EPA for a Phase II Lake Restoration
Program if Lynn Lake qualified for a Phase I grant
7. Implementing the restoration program
Lake Restoration Advisory

Committee
The first step in the restoration program was to form an advisory committee that
would be responsible for providing direction throughout the program. A commit-
tee representing the various interests in the watershed was formed and con-
sisted of representatives from the following municipalities, agencies and
groups:
Friends of Lynn Lake - a fund-raising organization
Lynn Lake Fishing Club
Kent County
The Kent County Homebuilders Association
Kent County Soil and Water Conservation District
U.S. Soil Conservation Service (SCS)
Middletown Sewer Authority
State Water Control Board
State Health Department
State Highway Department
East Kent Garden Club
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Responsibilities of the Lake Restoration Advisory Committee included:

• Reviewing consultant qualifications and recommending a consultant to
the County Commissioners
• Providing direction throughout the project by frequently meeting with the
consultant
• Reviewing the consultant's work including data analysis, conclusions,
and recommendations
• Obtaining public input to the proposed management alternatives

• Approving the final lake and watershed management plan prepared by
the consultant
• Recommending the acceptance and implementation of the management
plan to the County Commissioners
• Assisting in the implementation of the lake and watershed management
plan.
Consultant Selection
Since no one involved in the project was experienced in lake studies and res-
toration, the county decided to retain a consultant to assist them in developing a
lake restoration program. Realizing that they would be applying for Federal
funds from the EPA's Clean Lakes Program, they followed the Federal procure-
ment guidelines provided in 40 CFR Part 33 - "Minimum Standards for Procure-
ment Under EPA Grants." The county decided to use the negotiation method of
procurement. The Advisory Committee mailed requests for qualifications to eight
firms, reviewed the qualifications, and interviewed three firms. They asked each
firm to indicate its specific experience in several of the lake management areas,
as listed in Chapter 3.
The Committee selected a consultant who demonstrated the necessary
qualifications and experience, especially the successful completion of projects
involving algae and weed problems similar to those experienced at Lynn Lake.
The consultant was selected to provide the following services:
1. Develop a detailed work plan that would meet all requirements of an EPA
Phase I Diagnostic/Feasibility Study
2. Develop a Phase I grant application
3. Perform a diagnostic study, with or without Clean Lakes funding
4. Assist in the selection of a cost-effective restoration program
5. Develop a grant application for the Phase II Lake Restoration Program if
Lynn Lake appears to be eligible for such funding
6. Design in-lake and watershed management practices
7. Implement the restoration program
By including all of these tasks in the consultant selection process, the Com-
mittee ensured that one consultant would be involved from start to finish and that
further consultant selection procedures would not be required.
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Detailed Work Plan
The consultant developed a work plan that included the following activities:
1. Study of lake and watershed characteristics
2. Study of lake and watershed aesthetics and recreational characteristics
3. Limited lake monitoring
4. Limited watershed monitoring
5. Data analysis
6. Development and evaluation of management alternatives
7. Selection of a watershed management and lake restoration program
8. Projection of benefits
9. Environmental evaluation
10. Presentation to the homeowners association
11. Progress reports and final report
In developing the detailed work plan, the consultant reviewed the limited ex-
isting water quality data on Lynn Lake and evaluated the natural characteristics
of the lake and watershed. The consultant also met several times with the Ad-
visory Committee to discuss project goals, potential problem areas in the water-
shed (such as Middletown treatment plant, erosion from agriculture,
construction and roadway maintenance, and septic system leachate), and the
availability of local resources that could be used during the study.
In-kind services from local sources and State offices may be counted as part
of the State's contribution for Clean Lake Program funding. See Chapter 8 for
suggestions regarding Federal Agencies that may support lake restoration or
watershed management (nonpoint source control) programs.
To keep the diagnostic study costs to a minimum, the consultant decided that
the following local resources could be used as in-kind services:

Local in-kind services:

1. KENT COUNTY

• provide boat for lake monitoring

• provide land use data for study
• assist in the installation of watershed monitoring stations
• assist in the evaluation and selection of management alternatives
• assist in public participation activities
• review and comment on final report

• attend project meetings
2. SOIL CONSERVATION SERVICE

• identify agricultural problem areas
• assist in the identification and evaluation of agricultural control
measures, attend project meetings

• provide cost information

• provide technical information
• advise on funding through other USDA programs
7-7
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3. MIDDLETOWN SEWER AUTHORITY

• provide wastewater treatment plant effluent data

• analyze lake and stream samples in treatment plant laboratory

4. STATE WATER CONTROL BOARD

• review progress reports and final report

• attend project review meetings

The final work plan included a detailed description of study tasks, project
responsibilities, the project budget (cash and in-kind services), and the project
schedule. Costs for in-kind services were calculated using an hourly cost rate
based on salary plus overhead.
Phase I Grant Application
The county decided to apply for EPA Clean Lakes financing because the Lynn
Lake project appeared to be an ideal candidate. It not only met the criteria for
public access but was also the most heavily used public lake within a 3-hour
commuting radius. Furthermore, the lake's deterioration was pronounced;
without restoration the lake was likely to become unusable for several recrea-
tional pursuits within a few years. The enthusiastic public support for restoration
was also in the lake's favor. Clean Lakes funding provides a matching form of
grant (that is, 70% Federal, 30% State funds); both the county and the general
public were willing to support the cost of a restoration project.
The consultant developed a Phase I grant application that consisted of the
completed EPA application forms along with the detailed work plan. Although
the consultant developed the grant application for the county, the official ap-
plicant was the State Water Control Board since EPA regulations only allow
Clean Lakes Program grants to be given to State agencies. The State Water
Control Board, therefore, reviewed the grant application and submitted it along
with their priority ranking of the project.
After both the EPA regional and headquarters offices had reviewed and
evaluated the application, the EPA approved the application and offered the
State a Phase I grant. The State then subcontracted with Kent County to perform
the Phase I study. Kent County in turn contracted with the consultant to perform
the technical tasks of the Phase I study.
Lake and Watershed Study

Study of Lake and Watershed
Characteristics
The study of lake and watershed characteristics was performed primarily
by collecting and analyzing secondary data — data already available from
other sources including 208 Water Quality Management Plans, U.S. Geological
7-8
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Survey (USGS) maps, aerial photographs, and State and local publications.
Using these sources, the consultant obtained the following information:
1. Physical lake characteristics (area, depth, mean flow)
2. Some general chemical and biological characteristics of the lake (tempera-
ture, dissolved oxygen, nutrients, algal population, fish population)
3. Watershed characteristics (drainage area, land use, topography, geology,
and soils)
4. Possible pollutant sources (wastewater treatment plant discharge, con-
struction sites, agricultural areas, and failing septic systems)
Insufficient existing data were available to clearly define the lake's mean
depth, its volume, or its chemical and biological condition. The work plan was
designed to fill in these and other gaps in information. Also, although the con-
sultant, working with the input from the Advisory Committee, was able to identify
potential pollutant sources, available information was insufficient to quantify and
rank them.
The products of this task were some basic information about the lake and a
set of watershed maps illustrating land use, topography, geology, soils, and pos-
sible pollutant sources.
Study of Previous Uses and

Recreational Characteristics
Using existing reports and information, the consultant identified the following in-
formation on the lake and watershed:
1. Historical uses (walking, jogging, boating, swimming, fishing, and picnick-
ing)
2. Past lake problems (excessive algae, aquatic weeds, and siltation leading
to loss of recreational uses)
3. Public access locations
The product of this task was basic information on lake uses and users, infor-
mation useful for clarifying project goals and developing a management
program.
Lake Monitoring

Because of the lake's shape, three sampling stations were located on it, as
shown in Figure 7-2. One station was located over the deepest part of the lake
while the other two stations were located in the two arms of the lake to ade-
quately characterize lake quality. Samples were collected monthly from Septem-
ber through April and biweekly from May through August. Besides meeting EPA
monitoring requirements, the sampling program was designed to obtain more
samples during the warm weather period (May through August) when the
biological activity and chemical changes are at their maximum.
Three depths were sampled at each station because lake stratification oc-
curred. Water samples were collected at 1/2 meter below the surface, 1/2 meter
above the bottom, and near middepth. The middepth station was located within
the metalimnion, the water stratum where temperature and dissolved oxygen
changes the most.
7-9
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Dam
Figure 7-2.-Lynn Lake monitoring stations.
Each water sample was analyzed in the laboratory for the following chemical
parameters:
Total Phosphorus
Soluble Reactive Phosphorus
Organic Nitrogen
Ammonia Nitrogen
Nitrate Nitrogen
Total Suspended Solids
Alkalinity
Iron
Manganese
Field measurements at each sampling station included a temperature and dis-
solved-oxygen profile with measurements taken at intervals of 1 meter (using a
combined temperature-dissolved-oxygen meter). Field measurements also in-
cluded pH, conductivity, and Secchi depth. The Secchi depth measures the
transparency of the water.
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Water samples collected from the 1/2-meter depth were also analyzed for
chlorophyll-a, phytoplankton, and zooplankton. Chlorophyll-a measures the
algal biomass in the surface waters of the lake. The phytoplankton (floating
algae) and zooplankton (floating microscopic animals) analyses consisted of
identifying and counting the various algae and microscopic animals in the
samples.
A macrophyte (aquatic weed) survey was performed in August and consisted
of identifying the type and distribution of aquatic plants in the lake. Since siltation
of the lake is a problem, bathymetric (bottom contour) and sediment depth sur-
veys of the lake were performed to determine the water and sediment depth of
the entire lake. The surveys consisted of measuring the water depth with a depth
recorder and the depth of the unconsolidated (loose) bottom sediments by
probing with a steel rod at cross sections throughout the lake. A survey crew
was used to pinpoint the location of the cross sections.
At each of the three lake stations a sediment sample was collected and
analyzed for the following parameters:
Sediment Sample Parameters
Total Phosphorus Iron
Total Nitrogen Manganese
Percent Solids EP Toxicity Test
Percent Organic Solids

The products of this task were physical, chemical, and biological data on the
lake water and sediments. These data would be analyzed later to determine the
present ecological condition of the lake. Another product of this task was
bathymetric data that would be used to calculate the volume of the lake and to
determine whether dredging was a feasible management alternative.
Watershed Monitoring
As discussed in Chapter 4, the first step in analyzing and modeling a lake is to
establish a water balance and budget of materials (for example, nutrients, sedi-
ment, organic matter). Chapter 4 also indicated that a water balance and
materials budget could be obtained either indirectly by comparing the water-
shed to a similar watershed or directly by monitoring the streamflow and pol-
lutant loads over a 1-year period. The direct measurement method is obviously
more accurate and reliable than the indirect estimate method, but it also requires
more resources. Since sufficient funds and resources were available, the direct
measurement method was used to calculate an annual water balance and pol-
lutant budget.
To calculate an annual sediment and nutrient budget for Lynn Lake, the con-
sultant with assistance from Kent County installed stream monitoring stations on
Kimmel Creek, Tag Run, and the lake's outlet as shown in Figure 7-3. Each
stream station consisted of an automatic water level recorder and sampler.
Volunteers serviced the station. The consultant measured cross-sectional area
and velocity of the stream during selected rain events. This information was
used to develop a stream rating curve that correlates stream water level with
streamflow. This information was used in conjunction with the water level read-
ings to calculate streamflows throughout the study period. A staff gage was also
installed in the lake to monitor changes in lake level and thus water storage (or
loss) to or from the lake.
In some lakes, groundwater income can be a very important source of water
and, sometimes, of nutrients. Because Lynn Lake had a very high income of
water via the two streams, it was believed that groundwater was an insignificant
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Figure 7-3.-Location of stream monitoring stations.
component of the overall water budget. In reservoirs, this may often be the case.
In many natural lakes, stream inflow is small, and groundwater may be very im-
portant. In these cases, wells would have to be placed around the lake and
groundwater inflow determined. At the same time, nutrient concentration in
groundwater would also be determined.
An automatic water sampler (Fig. 7-4) was electrically connected to the water
level recorders and programmed to collect water samples when the stream level
increased during rain events. These are water level changes that occur very
rapidly, often (it seems) during the night or on holidays when volunteers cannot
be present to note them. During each rain event, discrete water samples were
collected at 1/2-hour intervals over the stream hydrograph as shown in Figure
7-5. (Depending on the size of the stream and land use in the watershed, the
sampling time interval can be adjusted from 15 minutes to several hours.)
After each storm event, selected water samples were taken to characterize sedi-
ment and nutrient loading at various times during the storm. Samples (that is,
1-2 samples) were taken as the flow increased, near the peak discharge, and as
the flow decreased.
Each selected sample was analyzed for the following parameters:
Total Phosphorus Ammonia Nitrogen
Soluble Reactive Phosphorus Nitrate Nitrogen
Total Nitrogen Total Suspended Solids
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Figure 7-4.-Automated stream monitoring station used to collect flow and water quality
data.
E
to
CD
+-•
C/)
Storm Hydrograph
Time
Figure 7-5.-Typical stream hydrograph showing increase in stream water level during a rain
event and showing how an automatic sampler collects water samples at select time inter-
vals.
7-13
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These selected samples permitted the development of a nutrient/sediment
concentrations versus flow relationship that was used to estimate loads during
nonsampled storms, based on the flow records.
A total of nine storm events were monitored. These nine storm events
provided sediment and nutrient loading data representative of nonpoint source
pollution such as watershed erosion and runoff. Dry weather stream monitoring
was also performed to obtain baseflow stream loading data. Dry weather stream
monitoring consisted of collecting grab samples from the two tributaries and the
lake's outlet once each month during the study. Each sample was analyzed for
the same variables as the wet weather samples.
The products of this task were flow and water quality data for both dry and
wet weather conditions for the two tributaries and the lake's outlet, as well as
changes in water storage in the lake. Water loss via evaporation and water fall
directly on the lake were estimated from data obtained at a nearby National
Oceanic and Aeronautic Administration (NOAA) weather station.
Data Analysis

Lake Analysis

The lake's mean and maximum depths and volume were calculated for the
bathymetric survey data. The hydraulic residence time, the theoretical time re-
quired to displace the lake volume as explained in Chapter 2, was calculated
using the lake volume and the mean annual discharge from the lake. The limiting
nutrient was suggested by the nitrogen to phosphorus ratio in the lake during the
study period. If the total nitrogen to total phosphorus ratio is greater than 10 to 1,
phosphorus is usually the limiting nutrient. Throughout most of the study, the
nitrogen to phosphorus was generally greater than 17, indicating that phos-
phorus was generally the limiting nutrient. Therefore, the in-lake and watershed
management program should be concentrated on reducing phosphorus loads
entering and within Lynn Lake.
Figure 7-6 illustrates some summer temperature and dissolved-oxygen
profiles for Lynn Lake. Temperature stratification began in late May and became
progressively more pronounced over the summer. In most cases, a shallow lake
with as large a surface area as Lynn Lake's would destratify frequently from sum-
mer storms. Lynn Lake, however, is sheltered from prevailing winds by high
bluffs and trees so that it remains stratified all summer. Cool weather in Septem-
ber, however, allowed enough heat loss from the lake to make destratification
possible.
Dissolved-oxygen began to deplete in the bottom waters of Lynn Lake right
after the lake stratified. By mid-July the entire hypolimnion was devoid of
oxygen, a common symptom in a eutrophic lake. An absence of dissolved
oxygen in waters overlying the sediments provides ideal conditions for release of
phosphorus from the sediments to the water column. In Lynn Lake, summer-
long monitoring of phosphorus concentrations from surface to bottom
demonstrated that the hypolimnion had greatly elevated concentrations, and
studies before and after summer storms demonstrated that small mixing events
circulated some of this phosphorus to surface waters and stimulated immediate
growths of algae. A calculation of the rate of internal phosphorus release, using
phosphorus income-outgo data and changes in the amount of phosphorus in
the water column, revealed that 118 Ibs were released between the end of May
and the middle of September when Lynn Lake destratified. An introduction of
dissolved oxygen to bottom waters when the lake mixed in the fall changed
7-14
-------
0

30
May 13
June 16
July 14
July 28
Temp. 0 10 20 30 0 10 20 30 0 10 20 30 0 10 20 30
D.O. 0 5 10
August 11
15 0 5 10
August 25
15 0 5 10 15 0 5 10 15
September 10 September 23
Temp. 0
D.O. 0
10 150 5

• Temperature (°C)
10 150
10 15 0
•Dissolved oxygen (mg/1)
10 15
Figure 7-6.-Representative temperature and dissolved oxygen profiles for Lake Station 1.
Thermal stratification and dissolved-oxygen depletion occurred from June through mid-
September. Zero dissolved oxygen conditions in the bottom waters adversely affect the
cold-water fishery and cause the release of phosphorus from the lake sediments.

chemical conditions there, and more phosphorus was precipitated to the sedi-
ments than was released.
Chlorophyll-a and phytoplankton levels varied during the study. However, the
mean summer chlorophyll-a concentration was 18 ppb, which is indicative of
eutrophic conditions. During the summer and early fall, the phytoplankton was
dominated by nuisance blue-green algae. Except for periods after rain events,
the Secchi disk transparency decreased with increased phytoplankton levels. A
comparison of Lynn Lake data to EPA eutrophication criteria is presented in
Table 7-3. This comparison indicated that Lynn Lake is eutrophic. A summary of
Lynn Lake characteristics, based on study results, is presented in Table 7-4.
Table 7-3.—Comparison of Lynn Lake data to eutrophic classification criteria
(EPA, 1980)
PARAMETER
LYNN LAKE
EUTROPHIC CRITERIA CONCENTRATION
Total Phosphorus (ppb as P)
(winter)
Chlorophyll a (ppb)
(summer)
Secchi Depth (m)
greater than 25

greater than 10

less than 2.0
50.0

18.0

1.1
Another indication of Lynn Lake's eutrophic condition was found in Carlson's
index. This index, as Chapters 3 and 4 explain, can be a valuable tool for quan-
tifying lake trophic status from basic, readily attainable data. Indices calculated
from Lynn Lake range from 58 to 61, indicative of eutrophic conditions (see Fig.
7-7).
7-15
-------
Table 7-4.—Characteristics of Lynn Lake
Lake Area (acres)
Watershed Area (acres)
Watershed to Lake Area Ratio
Mean Depth (feet)
Maximum Depth (feet)
Volume (acre-ft)
Outflow (acre-ft/yr)
Mean Hydraulic Residence Time (years)
Tropic Condition
Limiting Nutrient
500
4400
9:1
20
45
10000
4501
2.2
. . Eutrophic
Phosphorus
OLIGOTROPHIC MESOTROPHIC EUTROPHIC HYPEREUTROPHIC
20 25 30 35 40 45
60 65 70 75 80
TROPHIC STATE
INDEX
TRANSPARENCY
(METERS)
• AVERAGE MEASUREMENTS
UNDER CURRENT CONDITIONS
Figure 7-7.-Carlson's Trophic State Index for Lynn Lake, indicating that Lynn Lake is eu-
trophic.
Evaluation of the lake data indicated that Lynn Lake was suffering from the fol-
lowing problems:

• excessive algal growth

• excessive weed growth in the inlet area

• excessive siltation in the inlet area

• phosphorus release from the lake sediments

Watershed Analysis

The lake and stream data were used to calculate an annual water balance and
nutrient budget, using the techniques discussed in Chapter 4. In addition to the
stream and outlet monitoring, data were also collected for the Middletown treat-
ment plant and for the quantity and quality of rainfall in the watershed. The an-
nual water balance was calculated using the equations provided in Chapter 4.
7-16
-------
Stream and lake data collected over a 1-year period consisted of water
quality data for 12 monthly dry-weather samples and nine composite storm
samples. The annual stream phosphorus load to Lynn Lake was calculated by
adding both the dry weather and wet weather loads. The dry weather or
baseflow load was calculated using the 12 monthly phosphorus concentrations
and the continuous streamflow data.
Since the nine monitored storms only represented a portion of the total
storms that occurred during the monitoring period, a statistical relationship be-
tween the total phosphorus concentrations and flow was used with other storm
flows to calculate the annual wet weather phosphorus load. The phosphorus
load for the area draining directly into Lynn Lake was extrapolated using the
stream load data.
The annual point-source load from the Middletown treatment plant was calcu-
lated from daily flow records and biweekly chemical data. The annual direct rain-
fall phosphorus load was calculated from rainfall quantity and quality data
collected during the study.
Table 7-5 lists the annual water balance and phosphorus budget for Lynn
Lake. This table follows the format provided in Table 4-1 of Chapter 4. It provides
a complete accounting of drainage areas, flows, and loading. Similar tables were
developed for nitrogen and sediment budgets.

Table 7-5.—Annual water balance and external phosphorus loading for Lynn Lake

ITEM
Kimmel Creek
Tag Run
UngaugedArea
WWTP
Atmosphere
Total
Evaporation
Outflow

AREA
ACRES
300
3500
100
500
4400
500
4400

FLOW
AC-FT/YR
375
3885
111
80
1250
5701
1200
4501
%PF
TOTAL
INFLOW
6.6%
68.1%
1 .9%
1 .4%
21 .9%
100.0%
21 .0%
79.0%
Net Phosphorus Retention
TOTAL P
LOADING
LBS/YR
180
315
9
655
89
1248
612
636
%PF
TOTAL
LOADING
14.4%
25.2%
0.7%
52.5%
7.1%
100.0%
0.0%
49.0%
51 .0%

RUNOFF
FT/YR
1.25
1.11
1.11
2.50
1.30
2.40
1.02

TOTAL P
EXPORT
LB/AC-YR
0.600
0.090
0.090
0.178
0.284

phosphorus loading model predictions for Lynn Lake
T - mean hydraulic residence time (years)
= Lake volume (ac-ft) / mean outflow (ac-ft/yr)
= 10,000 ac-ft / 4,501 ac-ft/yr
= 2 22 years
PI - average inflow p concentration (ppb)
- total p loading (Ibs/yr) x 368 / lake outflow (ac-ft/yr)
= 1,248 Ibs/yr x 368 / 4,501 ac-ft/yr
= 102 ppb
P = predicted lake phosphorus concentration (ppb)
= PI / (1 + VT)
= 102 / (1 + V2 22) = 41 ppb
observed lake phosphorus concentration = 50 ppb

Application of the phosphorus loading model described in Chapter 4 (Table
4-2), to Lynn Lake yielded a predicted lake phosphorus concentration of 41 ppb,
as compared with the average measured concentration of 50 ppb. The higher
measured value suggested the presence of an additional external or internal
phosphorus source which is not considered in Table 7-5. Based upon geologic
factors and lake water balance information, the consultant concluded that sig-
nificant groundwater contributions were unlikely. Review of lake monitoring data
indicated that soluble phosphorus was released from bottom sediment during
periods when the bottom waters were devoid of oxygen. Severe algal blooms
often followed periods of high winds, which caused mixing of phosphorus-rich
bottom waters into the surface layer. Based upon these considerations, it was
concluded that lake bottom sediments were likely to be important internal sour-
ces of phosphorus which should be addressed in a restoration program.
7-17
-------
Since the external loads listed in Table 7-5 do not indicate specific land uses
or activities that produced these loads, the consultant performed field investiga-
tions throughout the watershed to identify specific nonpoint source problem
areas. The study indicated that Tag Run is in good condition. The Soil Conserva-
tion Service provided specific information on problem agricultural areas in the
watershed. Active construction sites were also visited to estimate the magnitude
of soil erosion occurring during rain events. Based on the external phosphorus
budget and an evaluation of the field investigation, the consultant concluded that
the following phosphorus sources were significant and should be controlled:
• Middletown wastewater treatment plant
• agricultural activities (Tag Run)
• construction activities (Kimmel Creek)

Evaluation of Management Alternatives

Management alternatives for Lynn Lake were divided into watershed manage-
ment and in-lake management alternatives. The first priority was to determine
whether watershed management practices were needed to reduce the pollutants
entering the lake. After all, the best in-lake management program will not suc-
ceed if an excessive income of nutrients, silt, and organic matter continues to
enter the lake. Therefore, it is important to determine whether the annual pol-
lutant load to the lake is excessive. For Lynn Lake, the significance of annual
phosphorus loading to the lake was estimated by using the Vollenweider Phos-
phorus Loading Diagram shown in Figure 7-8. This diagram is explained in
Chapter 4. This curve, relating the average inflow phosphorus concentration to
the ratio of mean depth to hydraulic residence time, indicates that the annual
phosphorus loading to Lynn Lake is probably excessive and should be control-
led.
Future projections for Lynn Lake shown in Figures 7-7 and 7-8 assume im-
plementation of the recommended management strategies, as described below.
Advanced treatment of Middletown wastewater discharge would reduce annual
external phosphorus loading by 491 pounds per year. The consultant estimated
that implementation of the recommended watershed management practices
would reduce the phosphorus loading from Kimmel Creek by approximately 25
percent, or 45 pounds per year. Overall, the external phosphorus loading would
be reduced by 43 percent from 1,248 to 741 pounds per year. Figures 7-7 and
7-8 indicate that this reduction would restore Lynn Lake to a mesotrophic status.
Average water transparency would increase from 1.1 to 2.7 meters and average
chlorophyll-a concentrations would decrease from 16 to 5 ppb. The selection of
specific alternatives to achieve these results is described in the next section.

Evaluation Criteria

The following criteria were used in the evaluation of lake and watershed manage-
ment alternatives:
• effectiveness
• longevity
• confidence
• applicability
• potential negative impacts
• capital costs
• operating and maintenance costs
7-18
-------
1000
m
Q.
a.

6
2
O
<•>
w
100
I
O o
i
o
10
I LYNN LAKE | . •

CURRENT CONDITIONS
P=6
_ __ —POST-RESTORATION
HYPER-EUTROPHIC
EUTROPHIC,
MESOTROPHIC
p=io
OLIGOTROPHIC
PREDICTED LAKE PHOSPHORUS (PPB)
l
.01 .1 1 10 100

HYDRAULIC RESIDENCE TIME (YEARS)
LAKE VOLUME/OUTFLOW

Figure 7-8.-Vollenweider phosphorus loading curve for Lynn Lake indicating that Lynn Lake
is eutrophic and receiving excessive phosphorus loading.
Effectiveness

Effectiveness relates to how well a specific management practice meets its goal.
For instance, dredging would be considered effective if it met the identified goals
of increasing the lake's depth and capacity, removing excessive nutrients from
the lake, and eliminating weed problems. A management practice may be par-
tially effective in that goals may be incompletely met. For instance, dredging
may increase the depth and capacity, but excessive nutrients may still exist in
the remaining sediments or algae may continue to be a problem in some areas
of the lake.
For some management practices, such as dredging, the effectiveness can be
determined initially based on the specific design and extent of the practice. If all
of the loose sediments are removed from the lake, all goals will be met.
However, if funds are limited and only partial dredging is carried out, only partial
effectiveness will be obtained. The decision, therefore, becomes a trade-off be-
tween effectiveness and other factors such as costs, available funds, negative
impacts, and public acceptability.
For other management practices such as alum treatment or sedimentation
basins, effectiveness is not straightforward and cannot be completely defined
prior to implementation. Alum treatment, for example, depends upon many fac-
tors that could influence its effectiveness. If, following alum addition, high sedi-
ment or nutrient loads continue to enter the lake, the beneficial effects of alum
treatment would be negated. Similarly, a detention basin is designed to treat a
specific streamflow. If rain events occur that produce a streamflow in excess of
the design flow, the effectiveness of the basin will be reduced. Effectiveness of
management practices, therefore, must be evaluated based on the past ex-
perience of the effectiveness of the practice, the commitment to implement part
or all of the required practice, and an analysis of the risks and variabilities in-
volved.
7-19
-------
Longevity

Longevity reflects the duration of treatment effectiveness. Treatments are usually
categorized as short-term or long-term. A treatment or management practice is
defined as short-term if it is effective for one year or less. Weed harvesting, for
example, is usually a short-term technique that is immediately effective, but may
only last for a period of several weeks or a single growing season. The short-
term longevity of a treatment or management practice, however, is not inherent
in the process; it usually varies with specific environmental conditions. Three
copper sulfate treatments might control algal blooms on one lake for an entire
growing season, while on another lake, weekly treatments would be necessary
to overcome the effects of a high flushing rate and incomes of new nutrient-
laden water. Treatment or management practices that produce short-term ef-
fects will result in long-term effectiveness if they are reapplied each year. For
example, a farmer may use conservation tillage each year to produce a long-
term benefit from the method.
A treatment or management practice is usually defined as long-term if it is ef-
fective for more than a year. The long-term effectiveness, like short-term effec-
tiveness, depends on both environmental conditions and the specific
management practice. A sedimentation basin will provide long-term treatment
effectiveness if it is properly designed for specific environmental conditions,
such as streamflow fluctuations and pollutant loadings, and if it is properly main-
tained. If, however, the basin was designed too small, it will not continue to
remove pollutants effectively. If the accumulated sediments are not periodically
removed, the long-term effectiveness will be decreased by poor maintenance.
Dredging will provide long-term effectiveness if the dredging program was
properly designed and if watershed management practices have already been
implemented. If excessive siltation still occurs, the long-term effectiveness of
dredging will be decreased. Construction of grass waterways on farmland will
provide long-term effectiveness if properly designed and if maintained each
year.
Confidence

Confidence refers to the number and quality of reports and studies supporting
the effectiveness rating of a treatment. Some in-lake procedures such as dredg-
ing have been extensively applied and studied. Confidence in the effectiveness
of dredging is high, based on its record of successful application. Other techni-
ques such as lake aeration have not been studied as extensively, and their con-
fidence evaluation is therefore lower. In addition, poor confidence can arise from
a variable record. It is not currently understood, for example, why aeration works
well in some lakes and does not in others.
Applicability

Treatment applicability refers to whether or not the treatment directly affects the
cause of the problem and whether it is suitable for the region in which it is con-
sidered for application. For example, nutrient concentrations in runoff from Mid-
western agricultural fields are often high and promote noxious algal blooms. The
perceived problem is algal blooms, but the cause is excessive nutrients. Nutrient
inactivation, with alum, can temporarily reduce nutrient levels in the lake water,
but cannot address the true origin of the problem — upstream agricultural water-
sheds. Nutrient inactivation, therefore, is not applicable to the problem of incom-
7-20
-------
ing nutrients; it can be applicable, however, to the problem of nutrient release
from sediments into the water column. Flushing may be highly applicable where
water is plentiful, but not in a region where water is scarce.
Potential Negative Impacts

Lakes are dynamic ecosystems; changing one element of the lake ecosystem
may cause a beneficial or adverse change in another element. In developing a
lake management program, the lake manager should take a holistic view of the
ecosystem to ensure that a proposed management practice does not cause a
negative impact on the lake ecosystem. For example, control of algae may bring
about an expansion of the submersed macrophyte problem penetration. Ob-
viously, some practices have short-term negative impacts that cannot be
eliminated. Dredging usually destroys the bottom-dwelling organisms, but new
organisms usually recolonize within a year.
Capital Costs

Standard approaches should be used to evaluate the cost effectiveness of
various alternatives. In evaluating costs of alternative methods, the lake manager
must balance the other factors already described; namely, effectiveness, lon-
gevity, confidence, applicability, and potential negative impacts. It is rare that the
benefits of different management practices are equal. Furthermore, limited funds
and resources often force the lake manager to select the most affordable rather
than the most cost-effective alternative. Many municipalities and lake associa-
tions elect to treat their lakes' weed problem annually with a herbicide rather
than dredge their lakes because they do not have sufficient funds for dredging.
Assuming, however, that the benefits of alternative management practices are
equal or nearly equal, the annual cost method should most likely be used to
determine the most cost-effective alternative. In this method, all costs must be
calculated using the same discount rate, and the annual cost must be based on
the same period of analysis.
An example of the annual cost method is provided for comparing dredging
and alum treatment of Lynn Lake. The targets of dredging and alum treatment
are almost the same - to reduce phosphorus in the lake.
Cost Comparison: Alum Treatment Versus Dredging

Assume:
1. Dredging has a lifespan of 20 years, assuming that 1 foot of sediment is
uniformly removed over 150 acres and that external loading is reduced.
2. Alum treatment has a lifespan of 6 years.
3. Benefits are equal.
4. Dredging has a one-time cost of $500,000 ($2 per yd3).
5. Alum treatment costs $35,000 every 6 years, assuming that the entire area
beneath the metalimnion (100 acres) is treated at a cost of $350 per acre.
The annual cost method is often used to compare alternatives. The main ad-
vantage of this method over all other methods (such as present worth) is that it
7-21
-------
does not require making the comparison over the same number of years when
the alternatives have different lives. The equivalent annual cost is calculated as
follows:
Equivalent Annual Cost = Present Cost (Capital Recovery Factor)
The capital recovery factor is obtained from standard interest tables for
various interest rates and time periods. Figure 7-9 shows a typical table for an
interest rate of 6 percent. Based on the assumptions described above, the cost
analysis is as follows:

Annual Cost for Dredging Lake: From Figure 7-9 for a time period of 20
years (N =20), the capital recovery factor is 0.08718. Therefore, the equivalent
annual cost is calculated as follows:
Equivalent Annual Cost = $500,000 (0.08718) = $43,590/year

6.00%
Discrete Cash Flow
Discrete Compound Interest Factors
Single payments I
Compound
Amount
N P/P
i
2
1
i«
5
6
7
8
1
10
1 1
12
13
11
15
16
17
18
19
20
22
214
25
26
20
30
32
3U
35
36
38
10
15
so
55
60
65
70
75
80
85
91
95
100
1.0600
1 . 1236
1. 1910
.2625
.3382
.1185
. 5036
.5938
.6895
.7908
1 . 8903
2.0122
2. 1329
2. 2609
2. 3966
2.S10U
2.6928
2.8513
3.0256
3.2071
3.6035
1 . 0189
1. 2919
1 . 5191
5.1117
5.7U35
6.153H
7. 2510
7.686 1
8.1173
9. 15U3
10. 2957
13. 7616
18.1202
21. 6503
32. 9877
1<4 . 1150
59.C759
79.0569
105. 796
11 1.579
189.165
253.516
339.302
Present J
Worth |
P/F 1
0.91 31
0.8910
0.8396
0.7921
0.7173
0.7050
0.6651
0.6271
0.5919
0.5511
0.5268
0.1970
0.1688
0.1123
0.1173
0. 3936
0.3711
0.3503
0. 3305
0. 31 18
0.2775
0.2170
0.2310
0.2 198
0. 1956
0.1711
0. 1550
0. 1 379
0.1301
0. 1227
0. 1092
0.0972
0.0727
0.051 1
0 .01 06
0.0 J03
0.0227
O.P 169
0.0 126
0.0095
0.0071
0.0053
0.0039
0.0029
Uniform series payments
Sinking
Fund
A/F
1 .
0.
0.
0.
0.
0.
0.
0.
1.
0.
0.
0.
0.
0.
0 .
0.
0.
1.
0.
0.
0.
0 .
0.
0.
0 .
0.
0.
0.
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0.
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1 .
0.
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0.
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roooo
1B511
31111
22859
17710
11336
11911
10101
C8702
C75S7
06679
0592S
05296
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01296
Q3895
C3511
C3236
C2962
027 18
C2305
01968
01823
01691
01159
01265
01 101
Q0960
C0897
00810
C0736
00616
C0170
00311
00251
01 1HR
C01 39
00103
C0077
C1057
riPI 3
00032
00021
OOP18
Compound
Amount
F/A
i .
2.
3.
1.
5.
6.
8.
9.
1 1.
13.
11.
16.
18.
21 .
23.
25.
28.
30.
33.
36.
13 .
50.
51.
59.
68.
79.
91.
101.
111.
1 19.
1 35.
151.
212.
290.
391 .
533.
719.
967.
1 301.
1716.
2312.
3111.
1209.
56 38.
TOO
060
181
375
637
975
391
897
191
181
972
870
882
015
276
673
213
906
760
786
392
816
865
156
528
058
891
181
135
121
901
762
711
336
17?
128
18 i
032
919
600
982
175
101
368
Capital
Recovery
A/P
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
p
0
0
0
0
P
0
0
0
0
p
0
0
p
0
n
p
0
0
0
0
0
.06000
.51511
. 1711 1
. 28859
. 23710
.21336
. 17911
. 16101
. 11702
. 13587
. 12679
. 1 1928
. 1 1296
. 11758
. 10296
.19895
.09511
.19236
.08962
.08718
.08305
.07968
.07823
. 17690
.07159
.07265
. 17 100
. 06960
. 06897
. 06839
. 06736
. If 616
.06170
.06311
. 06251
. 06 1H8
.06139
. 06 103
. 06077
. 06057
. P601 3
.06032
. 16021
. 06018
Present
Worth
P/A
0.
i.
2.
3.
1.
1.
5.
6.
6.
7.
7.
a.
a.
9.
9.
10.
10.
10.
1 1.
1 1.
12.
12.
12.
1 3.
1,3.
1 3.
11.
11.
11.
11.
11.
15.
15.
15.
15.
16.
16.
16.
16.
16.
16.
16.
16.
16.
9131
83 11
67 )0
1651
2121
9173
5921
2098
80 17
3601
8869
3838
8527
2950
7122
1059
1773
8276
15R1
1699
01 16
5501
7831
0132
1P62
7618
0810
3681
1982
6210
8160
016 3
1558
76 19
9905
1611
2891
3815
1558
5091
5189
5787
6009
6175
N
i
2
1
1
5
6
7
a
9
10
1 1
12
1 3
1 1
15
16
17
18
19
20
22
21
25
26
28
30
32
31
35
36
38
10
15
50
55
60
65
70
75
80
85
90
95
101
Figure 7-9.-Discrete cash flow of 6.00% discrete interest factors. Blank and Tarquin, 1983.
7-22
-------
Annual Cost for Alum Treatment: From Figure 7-9 for a time period of 6
years (N = 6), the capital recovery factor is 0.20336. Therefore, the equivalent
annual cost is calculated as follows:
Equivalent Annual Cost = $35,000(0.20336) = $7,118/year
From this comparison, it is obvious that alum treatment is the more cost-ef-
fective alternative since the equivalent annual cost is $7,118 for alum treatment
and $43,590 for dredging. Cost estimates for these treatments, while based on
an average of some actual case histories, cannot be applied, even as estimates,
to any other real lake situations. Each lake will have important and unique fea-
tures that will produce unique unit costs.
Watershed Management Alternatives

Watershed management practices, described in Chapter 5, consist of numerous
methods, including the installation of agricultural and silvicultural practices,
stabilization of eroding shorelines, erosion control for construction sites, runoff
control for all development, and the repair of failing septic systems. It also in-
cludes nonstructural practices such as the development of model erosion and
runoff control ordinances.
To be cost effective, watershed management practices should be imple-
mented in priority areas. Priority rating systems usually include factors such as
proximity to lake, existing pollutant loadings, potential reductions in pollutant
loadings, and costs. For small watersheds where specific, limited watershed
management alternatives can be identified, the evaluation and selection process
is relatively straightforward and can be performed as described later in this
chapter. However, for large watersheds where only large-scale generic water-
shed management alternatives such as agricultural practices or streambank
erosion control can be identified, the selection process is more complicated. For
small watersheds, the costs and effectiveness of management practices can be
readily estimated, but for large watersheds neither can be easily identified.
Therefore, selection of a management program for a large watershed is much
more subjective and qualitative than for a small watershed. By its very nature, a
large watershed management program must be evolutionary and long term-
First, priority areas are identified; then the most suitable management practices
are selected and implemented.
The watershed management information contained in Chapter 5 was used in
evaluating the effectiveness, longevity, and applicability of various watershed
management practices.
Based on the results of the diagnostic portion of the study, the consultant for
Lynn Lake identified specific priority areas in the watershed. These areas in-
cluded the Middletown wastewater treatment plant, specific agricultural areas in
the watershed, and several developing areas of the watershed. Various manage-
ment practices for each high-priority area were identified and evaluated using
the evaluation criteria discussed previously. An evaluation matrix, shown in
Table 7-6, was developed to evaluate the various management practices Infor-
mation from Chapter 5, Managing the Watershed, and other reference sources
was used to develop a rating based on conditions specific to Lynn Lake such as
land use, activity, soil conditions, topography, and pollutant loadings. This
matrix format can be used for decisionmaking on any lake. The evaluations in
Table 7-6, however, apply only to Lynn Lake.
7-23
-------
Wastewater Treatment Plant Upgrade

Table 7-5, the annual phosphorus budget for Lynn Lake, indicates that the Mid-
dletown treatment plant contributes 52.5 percent of the annual total phosphorus
income to Lynn Lake. In addition to being the dominant phosphorus source, the
treatment plant discharges phosphorus primarily in the form of soluble reactive
phosphorus, a form readily available for algal and weed growth. Also, the plant
discharges this highly available phosphorus throughout the year, even during
summer low flow conditions. It is important, therefore, that this phosphorus
source be significantly reduced.
There are two alternatives for eliminating or reducing the phosphorus entering
the lake from the treatment plant: diverting the plant effluent to another water-
shed that is not adversely affected by high phosphorus levels or providing ter-
tiary treatment to remove a significant portion of the phosphorus from the plant's
effluent. Diversion of the treatment plant's effluent to another watershed was
rejected because the cost of the pipeline and pumping station needed for the
diversion would cost approximately $400,000 - more than the cost of adding ter-
tiary treatment to the plant. It was also rejected because the citizens in the ad-
jacent watershed opposed the diversion of effluent to their watershed.
The addition of tertiary treatment facilities to the existing secondary treatment
plant would reduce the effluent phosphorus concentration by 75 percent, from 2
ppm to 0.5 ppm. The tertiary treatment facilities would include the addition of a
sand filter and alum treatment to the existing plant. Addition of the tertiary
facilities would cost approximately $300,000 for the 100,000 gallon-per-day treat-
ment plant. Operation and maintenance costs would increase by about 25 per-
cent primarily because of increased chemical and sludge disposal costs.
As shown in Table 7-6, the addition of tertiary treatment facilities to the Mid-
dletown plant was rated excellent for all categories except capital, operations
and maintenance costs. Although the costs of tertiary treatment are high, ter-
tiary treatment must be implemented to reduce the dominant phosphorus load
to Lynn Lake.
Sedimentation Basins

An effective practice for controlling sediment and phosphorus loads to Lynn
Lake is the construction of sedimentation basins on the major tributary streams,
just upstream of the lake. As shown in Table 7-6, the basins were rated "good"
overall, except for the costs, which were rated "fair." Construction of the basins
would only be cost effective if upstream watershed management practices were
not implemented or were not effective. Construction of the basins, therefore, was
rejected and postponed until upstream management practices could be imple-
mented and evaluated. If additional sediment and phosphorus load reductions
were required after upstream management practices were implemented, then
the construction of the sedimentation basins should be reconsidered.
Agricultural Practices

The ratings of agricultural practices, shown in Table 7-6, were developed in con-
junction with the Soil Conservation Service and the County Conservation Dis-
trict. Priority management practices were developed based on these ratings and
included animal waste management, grassed waterways, buffer strips, and con-
servation tillage. Secondary emphasis was given to pasture management, crop
rotation, and runoff diversion.
7-24
-------
Table 7-6.—Watershed management evaluation matrix

PRACTICE
Addition of Tertiary Treatment to Middletown
Treatment Plant
Construction of Sedimentation Basins at
Inlets to Lake
AGRICULTURAL PRACTICES
— Conservation Village
— Contour Farming
— Pasture Management
— Crop Rotation
— Terraces
— Animal Waste Management
— Grass Waterways
— Buffer Strips
— Diversion of Runoff
CONSTRUCTION CONTROLS
— Erosion Control Ordinance
— Runoff Control Oridnance
— Field Inspections
Legend: E = Excellent G = Good F

EFFECTIVENESS
E

F-E
F-G
F-G
F-G
F-G
E
E
E
G

E
E
E
= Fair P = Poor

LONGEVITY
E

G
P
E
G
G
E
E
E
G

E
E
E

CONFIDENCE
E

G
F
E
G
G
E
G
E
F-G

E
E
E

APPLICABILITY
E

G
G
G
G
G
E
G
E
F

E
E
E

POTENTIAL
NEGATIVE
IMPACTS
E

F
E
E
E
E
E
E
E
E

E
E
E

CAPITAL
F

F
E
E
E
F
F
G
G
F

E
E
E

O&M
F

F
E
E
E
G
F
E
E
G

E
E
E

01 ~ —
-------
Construction Controls

Construction-development controls were divided into three general categories:
• erosion control ordinance
• runoff control ordinance
• field inspections
An erosion control ordinance provides rules and guidelines to regulate the
control of erosion from an active construction site. Although the State has an or-
dinance to control erosion on construction sites, the Advisory Committee
recommended that the county enact a county-wide erosion control ordinance
more restrictive and enforceable than the State ordinance. In general, control of
erosion should be a local, not a State, regulated function.
A runoff control ordinance, in contrast to an erosion control ordinance,
provides rules and guidelines for controlling runoff and erosion from new
developments after construction is completed. The consultant developed a
runoff control ordinance that required that the peak postdevelopment
stormwater runoff rate not exceed the peak predevelopment runoff rate. It also
contained an equation for estimating the phosphorus load from the new
development and stipulated that the postdevelopment phosphorus load not ex-
ceed the predevelopment load.
No ordinance is effective if it is not adequately implemented and inspected.
Field inspections of all construction sites during and after construction are
necessary to ensure that all ordinance conditions are being met. All three con-
struction-development controls (that is, erosion control ordinance, runoff control
ordinance, and field inspections) were rated excellent in all categories in Table 7-
6. Implementation of all three controls will eliminate or significantly reduce runoff
and erosion problems for new developments.
In summary, the watershed management program recommended by the Ad-
visory Committee consisted of the following:
• Addition of tertiary treatment facilities to the Middletown treatment plant
• Implementation of priority agricultural practices in priority agricultural
areas
• Development and adoption of erosion control and runoff control
ordinances
• Development of a field inspection program for construction and
development sites
After these practices are implemented, the annual sediment and phosphorus
loads to Lynn Lake would be re-evaluated to determine whether additional prac-
tices, such as the construction of sedimentation basins, are needed.

In-Lake Management Alternatives

In-lake management practices applicable to the control of excessive algal and
weed growth and loss of depth were identified and evaluated using the informa-
tion contained in Chapter 6, Lake and Reservoir Restoration and Manage-
ment Techniques. Each management technique was evaluated based on the
lake and watershed data collected during the study. The results of this evalua-
tion, presented in Table 7-7, indicate that the most feasible and cost-effective in-
take management practices include the following:
• Alum treatment to precipitate and inactivate phosphorus
• Dredging of the lake inlet areas
7-26
-------
Table 7-7.—In-Lake management evaluation matrix

PRACTICE
Alum Treatment to Precipitate and
Inactivate Phosphorus
Dredging of Whole Lake
Dredging of Lake Inlet Areas
Dilution
Flushing Artificial Circulation
Hypolimnetic Aeration
Sediment Oxidation
Addition of Algicides
Food Chain Manipulation
Hypolimnetic Withdrawal
Water Level Drawdown to Remove Weeds
Weed Harvesting
Biological Controls to Reduce Weeds
Addition of Herbicides
Legend: E = Excellent G = Good F =
-si

EFFECTIVENESS
E
P
E
F
F
F
G
G
G
G
F
G
G
G
Fair P = Poor

LONGEVITY
G
E
E
F
F
F
G
P
Unknown
G
F
P
G
P

CONFIDENCE
G
E
E
F
P
F
P
E
P
G
F
G
F
G

APPLICABILITY
E
P
E
P
F
F
F
F
F
G
P
G
G
F

POTENTIAL
NEGATIVE
IMPACTS
F-G
F-G
G
F
F
F
G
P
Unknown
F-P
F-P
F
F-P
P

CAPITAL
COST
G
P
F
P
P
P
F
G
E
G
F
F
G
G

O&M
COST
G
E
E
P
F-P
F-P
G
P
E
E
G
P
G
P

-------
Alum treatment, after the addition of tertiary treatment to the Middletown
treatment plant, was selected because the study data indicated that internal cy-
cling of phosphorus from the lake sediments was a source of phosphorus to
Lynn Lake. The lake characteristics are conducive to alum treatment: The flush-
ing rate is low (0.45 times per year), and the annual phosphorus loading after
watershed management practices are implemented will be relatively low. Lab
studies were performed to determine the alum dosage required to both remove
phosphorus from the lake water and to inactivate (seal) the phosphorus in the
sediments. Additional alum treatments may be required every 6 years based on
case studies of other similar lakes treated with alum.
Alum treatment on a 3- to 5-year basis was compared to dredging of the
whole lake using the cost comparisons described earlier. Alum treatment was
judged the most cost-effective method of controlling phosphorus from lake sedi-
ments. If, however, a secondary benefit, lake deepening, was added, dredging
of the whole lake may be the most cost-effective alternative. However, since
Lynn Lake is deep enough for its intended recreational uses, lake deepening was
rejected as a benefit, and alum treatment was selected as the practice to inac-
tivate phosphorus in the sediment.
Dredging of lake inlet areas, however, was selected as a feasible manage-
ment practice since the siltation of the lake primarily affected the inlet areas that
were shallow and unusable for boating. Many of the aquatic weeds also grow in
these inlet areas.
Other in-lake practices were rejected for a variety of reasons. Dilution and
flushing were rejected because a source of dilution water was not available.
Pumping of groundwater to flush and dilute the lake was rejected because of
high costs and the potential depletion of groundwater. Aeration of the whole
lake was rejected because of the lack of confidence in the practice and the high
capital and operation costs. Insufficient data are available on the effectiveness
of whole lake aeration. Hypolimnetic aeration (aerating only the bottom waters)
was rejected because it was evaluated "fair" in all categories except costs, which
were rated "poor." Sediment oxidation was rejected because of the "poor" con-
fidence rating; insufficient data are available on the effectiveness of sediment
oxidation.
The addition of algicide was rejected because it is a "Band-Aid" approach that
has poor longevity and produces negative environmental impacts. Algicide,
however, can be added on a temporary basis while the watershed management
program is being implemented, but algicide should not be used as a long-term
management program. Weed harvesting and the addition of herbicides were
also rejected for similar reasons.
Food chain manipulation was rejected because the longevity and negative im-
pacts are unknown and the confidence level was rated "poor." Biological con-
trols to reduce weeds were rejected for lack of confidence. Water-level
drawdown, although it was rated "good" for effectiveness, was rejected because
the citizens did not want the lake water lowered.
Hypolimnetic withdrawal, the discharge of nutrient-laden bottom waters, was
temporarily rejected because of concern over potential downstream impacts
and potential in-lake effects on the thermal stratification of the lake. Discharge of
bottom waters high in nutrients and low in dissolved oxygen could adversely af-
fect water quality downstream of Lynn Lake. The Advisory Committee decided
that these potential impacts should be further investigated before a bottom dis-
charge would be allowed.
In summary, the in-lake management program recommended by the Advisory
Committee consisted of the following:
• Alum treatment to precipitate and inactivate phosphorus
• Dredging of the lake inlet areas
7-28
-------
Public Hearing

Prior to the final selection of watershed and in-lake management alternatives, the
Advisory Committee held a formal public hearing. The consultant presented an
overview of the study along with a description of the conclusions and proposed
management plan. In describing the proposed management program, the con-
sultant clearly explained the evaluation criteria used in developing the proposed
management plan. Comments from the public on all aspects of the study and
management plan were solicited by the Advisory Committee.
In general, the public comments were positive and supported the proposed
management program. Some questioned whether the restoration program
would cause an increase in county taxes. Others wanted to know whether their
sewerage fees would increase when the treatment plant was upgraded to ter-
tiary treatment. They were told that county taxes would not increase but that the
sewerage hookup and user fees would increase by a small amount.
Several citizens recommended that the monthly monitoring results for the
treatment plant's effluent be sent to the county and the Advisory Committee to
ensure that the plant met its treatment requirements. Others recommended that
the Advisory Committee be maintained until the management plan was com-
pletely implemented and that the county hire a full-time lake manager to oversee
the implementation of the management plan. The Advisory Committee directed
the consultant to include these recommendations in his final management plan.
Selection of Management Plan

The Advisory Committee in conjunction with the consultant presented the final
lake and watershed management plan to the County Commissioners for their
review. After they revised the plan, the Commissioners approved the plan and
directed the County Engineer to forward the Phase I Study Report and Manage-
ment Plan to the State Water Control Board and EPA for their reviews. The plan
was approved by both the State and EPA.
7-29
-------
CHAPTER 8
Implementing a
Management Plan
-------
CHAPTER 8

IMPLEMENTING A

MANAGEMENT PLAN

Management Means

Implementation
A well-evaluated and carefully designed management plan is useless if it is never
carried out, and it may be either useless or disastrous if it is but poorly followed.
Management includes not only diagnosing problems and evaluating alternative
solutions, but also includes putting the chosen plan into action.
Proper implementation requires money, manpower, planning and scheduling,
and permission. Even on private lakes, various permits and regulations must be
satisfied before many lake restoration techniques can be applied. If the water-
shed is not entirely owned by a single lake user, coordination among parties be-
comes a sizable task in itself. And, in all cases, education is a necessary
counterpart to accomplishment. It can never be assumed that the majority of
local residents will be aware of the major and minor disruptions to their tranquil
lake environment once implementation begins. Broadcasting the goals of the
project before work begins will foster both public support and patience during
the implementation phase.

Who Does the Work?

For many lake managers, homeowners, and other interested persons, the most
important step in implementation is the selection of a knowledgeable and ex-
perienced consultant or contractor. It is at the implementation stage that the
benefits of experience become obvious. The opportunities for delays, minor ac-
cidents, misunderstandings, and oversights in a restoration project are plentiful.
8-1
-------
Experienced contractors are more likely to foresee these problems and be better
prepared to handle unexpected ones.
Whoever pays the contractor has responsibilities as well. For example, an as-
sociation may hire a lake manager or consultant, who, in turn, hires contractors
to carry out various tasks. The lake manager represents the owners' interests.
The manager's responsibilities include overseeing the budget, oversight,
monitoring progress to ensure the project is on schedule, and acting as liaison
between the association and the contractor to be sure that both sides under-
stand each other's intents and that work is not delayed while the contractor
awaits important decisions.

Selecting Consultants or Contractors

Selecting the right consultant or contractor involves a number of considerations.
The criteria used in Chapter 3 will ensure that the selection process identifies
qualified contractors who have a responsible record and the right background to
solve the particular problem. The list in Chapter 3 also includes criteria for select-
ing a consultant who will be able to assist in other phases of lake management
such as identifying the problem, evaluating watershed and lake management
practices, and formulating the lake management plan as well as implementing
the plan once it is developed.
Consulting services can range from assistance in one specific area such as
lakeshore erosion to the design, execution, and implementation of the entire lake
management program. The expertise required for lake management can be spe-
cialized or broad, depending on the specific services requested, but should in-
clude limnology or aquatic ecology, watershed management practices, lake
restoration techniques, economic analysis, planning, engineering, and water
quality evaluations. Many lake associations prefer to work with a single firm from
the preliminary study to project completion, but it may be wise in some cases to
hire more than one consultant to take advantage of the strengths and specialties
offered by different providers.
The expertise needed to implement a lake restoration plan can be found at
universities, public and private research organizations, environmental consulting
firms, or engineering firms specializing in lake management. Many firms or
groups that specialize in lake management put together teams of individuals with
special experience and expertise that can be targeted to a specific set of lake
problems. In this case, the consultant or contractor may change team members
as needed to accomplish the work most efficiently. The North American Lake
Management Society (NALMS) also provides names of members who can
provide services by area of specialty.
Initially, identifying candidate consultants and contractors can be ac-
complished by contacting (1) other lake associations to find out who they have
used previously, (2) local and State environmental agencies and groups to find
out who has conducted similar studies in the past, (3) a referral service offered
through the NALMS, or (4) other professional organizations. Table 8-1 lists State
agencies that might be contacted, and Appendix E provides more detailed infor-
mation on various State and Canadian provincial agencies involved with lake
management. Because of the importance of the consultant or contractor in
properly implementing the lake management program, several individuals or
groups should be interviewed. The criteria listed in the case study in the previous
chapter can be used as a starting point for questions related to their expertise
and capabilities.
Asking for references is imperative. The hiring agency should write, or better
yet, call these references in addition to evaluating the responses of candidates to
interview questions. Lake management is not a cookbook process; there is
8-2
-------
some art to lake management as well as engineering and science. Innovation
should be an important criterion. There are, however, certain important com-
ponents in implementing any lake management program. These are discussed
in the remainder of this chapter. This information also can be used to initiate
questions for the consultant during the evaluation and selection process.
Institutional Permits, Fees,

and Requirements
Every State and many Federal agencies have institutional requirements (for ex-
ample, permits, fees, and notifications) that must be met before lake restoration
or watershed management practices can be implemented. Some of these re-
quirements are briefly summarized in Table 8-1. DO NOT assume this is a com-
plete list of all the agencies that need to be contacted. Local, city, and county
agencies might also require various permits or fees or fulfillment of necessary
conditions.
These institutional requirements, in many instances, are technique specific as
well. The requirements for dredging, for example, will be quite different from
those for herbicide application or harvesting. The U.S. Army Corps of Engineers
is authorized, after proper notice and public hearings, to issue general permits to
permit dredging or fill procedures if in the Corps' determination the dredging
operation will have minimal adverse environmental effects or impacts.
If a State has assumed permit responsibility, a copy of every permit applica-
tion is forwarded to the U.S. Army Corps of Engineers. Copies also are for-
warded to the Secretary of the Interior and the Fish and Wildlife Service. Some
States may have additional requirements, such as the State of Washington
where an application must be made to the State Department of Game for a
hydraulic permit for any alteration of the stream or lake bed, including the instal-
lation of a flow or temperature measuring device.
In a lake restoration plan that calls for dredging, taking the sediment out of the
lake represents only one part of the implementation process. The dredged
material, or spoils, must be properly disposed of as fill or taken to an approved
disposal area. Disposal procedures must conform with local, State, and Federal
requirements. This might require monitoring of the runoff or leachate from the
disposal area.
In addition to requirements for implementation of the various techniques,
there are also various OSHA requirements to protect the health, well-being and
safety of the individuals working on the project. Ear protection and safety shoes
might be required for the dredge workers, for example, or special safety precau-
tions might be mandated to protect workers while they are mixing chemicals for
alum applications or dispersing herbicides for weed control. An example of the
language that can be included in contracts to promote and ensure a safe im-
plementation program is shown in Appendix F. DO NOT assume this language
will satisfy the legal requirement in your State or county. Contact a local attorney
to be sure you are adequately covered.
The institutional requirements for each lake management program will
depend on the specific restoration and management practices proposed. If the
lake management plan is well organized and detailed beforehand, the various
agencies will be able to indicate the specific procedures and guidelines that
must be followed. Even if the lake manager or association is researching and
filing for all permits and fulfilling other requirements, it makes sense to ask con-
sultants and contractors if they are familiar with the appropriate regulations and
8-3
-------
Table 8-1.— Summary of state's lake programs
PERMITS
FORMAL silo
LAKES SUPPORTING FUNDING PERMIT i i S <
STATE PROGRAM AGENCIES STATE LOCAL AGENCIES 5 £ J S
Alaska None DEC State & Federal funding on a case on case DEC is is
by case basis
REQUIRED
<. i i
11 ill
B 8 g c i OTHER
IS IS IS
Anzona None F&G Management monies from Federal sources and F&G No formal permit required
hunting and fishing licenses
Arkansas None DPC & E Federal funding for lake classification DPC&E is is is
California None SWRCB, F&A, F&G, Legislative matching funds for 10 million to SWRCB >s ts V is
Local Government Lake Tahoe
(X is IS
Colorado None DOH Diagnostic studies DOH
Connecticut Legislation DEP 1 ) Small amount Lake authonties where DEP
budgeted for algae & lake is within boundar- wetland is is is
weed control IBS of more than one DEP water
2) Funding on case-by- town Town's budgets compl is
case basis through include lake work DEP
legislation pesticide is is
Delaware None DNR, F&W
Florida Grants DER DNR is is V*
DER *x Stormwater Permitting
GFC
WMD is
Georgia None DNR
Hawaii None No expressed need
Idaho Noformalpro- IDWH(DOE) AWQ Matching IDWH
gram but benefits (DOE)
from Agriculture
Water Quality
Illinois Lakes Program EPA, DOA, DOC, IDOA funding for soil EPA
Provides tech as- DENR, AISWCD conservation in priority
sistance and direc- watersheds $2 million/
tion. No grants. yearfor 5 years
Permits only for treatment of
public water supplies orfor
variances from water quality
standards.
Indiana DEM DEM, DNR DEM, DNR, no formal DR(FWL) V is
grants State
appropriations.
Iowa DNR, DALS Legislative None DNR is
Yearly appropriations to
DALS for erosion
control
is Flood plain management
-------
Table 8-1.—Summary of state's lake programs (cont.)
PERMITS
FORMAL < M S
LAKES SUPPORTING FUNDING PERMIT i S S 5
STATE PROGRAM AGENCIES STATE LOCAL AGENCIES J ¥ 5 S
Kansas Grants KDHE(WQA)F&G KDHE
Kentucky None DNR(DW),EP Matching
REQUIRED
5, t 3
i! I !!
No formal permit process.
Kentucky Dept. of Fish & Wildlife
controls introduction of grass
carp to control macrophyte
Louisiana None DEQ(OWR) State Matching Fees & Fines
Maine Grants EPA Planning Matching 75% of 25% Can levy fees DEP is >s is is
Committee $100,000 in 1982
is Sewer systems
Maryland None DHMH.OEP Local initiative
Massachusetts State Clean Lake DEQE Matching Matching DEQE is \s \s **
Program, Techni- DFW
cal Assistance
Michigan Inland Lakes DNR(ILU) 50% Matching DA
Management DNR-SWQ
&ILU
DNR-WMD
PNR-LR
Minnesota None MPCA, DNR, SWCD Some funds through Watershed districts MPCA
DNR for fisheries and have taxing authority
SWCD for land 50% match required
practices
Missouri None DNR(DivEQ) None U.S Army is
Clearinghouse (COE)DNR
Montana No formal pro- DH&ESDFWP Proceeds available DH&ES
gram; monies from coal tax by
may be alloted legislature.
from legislature
No formal permit process
LIST OF ABBREVIATIONS
DNR — Departmentof Natural Resources DENR — Departmentof Energy and Natural Resources
F&W — Fish & Wildlife DEP — Departmentof Environmental Protection
DER — Departmentof Environmental Regulation DWPC — Division of Water Pollut on Control
GFC — Game and Fish Commission DEC — Departmentof Environmental Conservation
EPA — Environmental Protection Agency DEQ — Departmentof Environmental Qual ty
WMD — Water Management District DWNR — Departmentof Water and Natural Resources
DOA — Departmentof Agriculture (state level) SWCB — StateWater Con rol Board
DOC — Department of Conservation DFW — Departmentof F sh and Wildlife
DOG — Department of Game DOE — Department of Ecology
DOH — Departmentof Health DOF — Departmentof F sheries
AISWCD — Association of Illinois Soil and Water Conservation Districts DILHR — Departmentof Industry Labor and Human Relations
01
-------
u> -
o>
Table 8 1. Summary of state's lake programs (corrt.)
DCdUITS
<3
5 1 1 2
. „.,«« c-i nMWMa-nfcjft FUNDING PEHMI1 m c c e
PROGRAM A™ES STATE LOCAL AGENCIES 5 t 1 3
Nebraska None WPC(DEC) None __ 1^2^
Nevada None (only DivEP Local motive. DIV.EP
; u M FiF<; nnA Local initiative. DOE *- v
New Hampshire None DES, DOA Wetlands
Board v f
F&G *
Pr-antc DEP Diagnostic/Feasibility Dcr
tationupto50%
New Mexico Inventory* EID Staff position Local mitotive Eg^ ""
G&F »
Newark Lakes Program DEC Projects funded through DEC * v »
Funds proTects State legislature on a
case-by-case basis
North Carolma No formal DHS.DWR.DWLR Legislative Case °WLR
nmnram DV Case _
North Dakota Grants DH {Div WS& PC) Matching
Fish & Game
Ohio No overall EPA(DWQMSA) Case-by-Case Basis OEDA& ^^
coordinated USGS, DNR, SWC, UNH
program. Div. W, Div WL, Local
soil & water conserva-
tion districts
Oklahoma None DPC Local initiative
Oregon No formal DEO State matching DEQ
Pennsylvania Mostly DER
REQUIRED
s, i S
§f 8 in
I 8 SET OTHER

tory board
r
const., or significant changes
to environment or at discretion
of DEP
v> shed management
• recommendation
• is V V Harvesting & Drawdown
depending on mag., location,
& importance of lake. EIS if
large, unusual project, Dredge/
Fill may Mine Land Reclama-
tion permit if spoils are great.
permit of DWR.

"
Rhode Island None DEM Federal, States, local OH Any a|teratlon water
quality or physical dis-
ruption of water course
-------
co

PERMITS
FORMAL _, m i
I AlfCO < Q P
bouth Dakota Lakes Program DWNR Water Facilities Con- Water Project Districts DWNR \£^±
struction-funds various can tax, pass bonds GTP *• v
water projects including Sanitary Districts can
lakes. Dredging grants set sewer fees Water-
;;. f. — ; up to 50% shed Districts can tax
program UIIJ.LO Local initiative DH&EC
Texas None TWRD
utan No formal DH(Div EH) ~~ Local — T~t n
program. initiative DH
Program Grants On-going funding
Proaram State 25% Local 25%
Virginia p^ram"9 W°B State and Federal funds WCB
Washington Grants DOE Phase 1 up to 75% -551= * * ^ ~
Phase II up to 75% nr;
W9St Virginia None DNR(DivWR) ~
Wisconsin LakeManage- DNR.DOA.DILHR Portion of Federal excise Lake Districts can tax. ~5NR 1^~^
mem program tax on recreation directed DOA
to Lake Management
Program provided project
improves sport fishery
Wyoming None DEQ Funds from EMOS Local initiative" npn
REQUIRED
1 Illll
Water quality variance

No formal permit process
<•» i«« <^ Permits required form-lake
treatments
"
•^ Hydraulic Permits
*•
LIST OF ABBREVIATIONS
DN^ — Department of Natural Resources HCMD r,
F&W _ Fish & Wildlife ncp ~~ DePartmentof Ener9y and Natural Resources
DER - Department of Environmental Regulation nwpr ~ Department of Environmental Protection
GFC - Game and Fish Commission n^r ~ Division of Water Pollution Control
EPA - Environmental Protection Agency npo ~ Department of Environmental Conservation
WMD - Water Management District nvvrjR ~ Department of Environmental Quality
DOA _ Departmentof Agriculture (state level) °WCB ~ Department of Wa.er and Natural Resources
DOC - Department of Conservation nFW ~ State Water Control Board
DOG - Department of Game nnp ~ Department of Fish and Wild ife
DOH - Department of Health ^OF ~ °ePar;mento'E<:ology
AISWCD _ Assoc,a,,ono,,,,lno,sSo,,andWa,erConserva,,onD,stnC,s SPLHR ~ o^So! ^labor and H,,man pola,,nn.
-------
agencies for the proposed lake management project. The degree of help and
completeness of information may be excellent in some government offices.
Other offices give out pertinent information more grudgingly, and only if the right
questions are asked. The contractor's previous experience will be especially
valuable if this latter situation is the case.
Implementation Costs Money
Two questions that arise from this statement are "How much will it cost?" and
"Are funds available to implement this project?"

Plans and Specifications
The first question can be addressed by having the consultant or contractor, lake
manager, or interested groups or individuals develop a set of plans and
specifications for the various lake management techniques that are feasible.
Economic considerations were part of the evaluation that preceded choosing a
management alternative, so a rough approximation of cost is already available.
At implementation, this estimate can be refined by pricing materials and man-
power needed; calculating the cost of the time required for implementation,
equipment needs, and any construction prior to implementation; and, finally, es-
timating the cost of a postmonitoring program.
The cost of postrestoration monitoring should be factored directly into the
overall cost of implementation because it is the only approach for evaluating
whether treatments are effective.
The preliminary set of plans and specifications does not have to be extremely
detailed because it will be revised before it is let for bids, but it needs to provide
sufficient information to approach potential funding agencies for money.
Funding Sources

Federal Agencies
For lakes with public access, the Clean Lakes Program, administered through
the U.S. Environmental Protection Agency, is a source of funds both for diag-
nosis and evaluation of lake problems and also for implementation of lake
management programs. The Clean Water Amendments of 1987 provide for both
Phase I (Diagnostic/Feasibility Studies) and Phase II (Implementation) manage-
ment programs to improve lake water quality. Much of the work discussed in this
Guidance Manual came out of Clean Lake Studies. New rules and regulations for
Clean Lakes funds are currently being prepared by EPA. Contact the State agen-
cies listed in Table 8-1 and Appendix E for information on the current program.
Funds also might be available from other Federal agencies for various
aspects of lake management. For example, funds might be available to aid in
solving water and pollution abatement problems on agricultural land through the
U.S. Department of Agriculture, Agricultural Stabilization and Conservation Ser-
vice (ASCS). Cost-sharing grants enable the design of management systems to
improve water quality and to stabilize runoff of nutrients or soils to water cour-
ses. Long-term agreements allow for preservation of wetlands areas.
Soil and water conservation are encouraged by grants and cost sharing
through the ASCS. Advisory service and counseling to improve flood prevention,
8-8
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streambank protection, and wildlife protection is also promoted. The Soil Con-
servation Service, which is primarily technical, administers the Rural Clean Water
Program grants.
Guaranteed and insured loans also are made available through the Farmers
Home Administration to improve farmland conditions such as soil conservation,
treatment of farm wastes, and reduction of fertilizer and pesticide runoff into
receiving areas.
The Forest Service offers research grants and financial assistance to improve
watershed management. Studies that determine the fate of pesticides and fer-
tilizers after forest applications are funded, as are reforestation research and
habitat improvement research.
Loans and project grants are available through the Department of Commerce
to encourage economic improvements in financially depressed areas. Support
for water and sewage facilities is an activity that aids in improving the water
quality of lakes and streams. In some instances, cities or regions that have
strong, organized offices of economic development have sponsored or provided
a great deal of assistance in lake projects.
The Office of Education provides educational grants to support research and
development of methods to improve public understanding of water quality is-
sues.
The Department of Housing and Urban Development supports a broad range
of planning and management activities to improve land management to protect
natural resources.
The Office of Mining Reclamation and Enforcement makes available grants
and payments to restore waters damaged by mining.
The Bureau of Reclamation improves recreation development and flood con-
trol and aids in protecting municipal and industrial water supplies through
project grants and loans.
The U.S. Fish and Wildlife Service aids in habitat development and in enhan-
cement of fisheries resources and researches the effect of pesticides on fish and
wildlife through formula grants.
The U.S. Geological Survey offers help to the States through cooperative
programs that provide 50 percent matching grants to investigate the
physicochemical properties of the State waters as well as the geology and quan-
tity of streamflow from watersheds and basins. This agency also manages the
State Water Research Institute Program, which can be of great assistance in
aiding lake restoration efforts.

State Agencies

The potential funding status of various State agencies is shown in Table 8-1. This
varies annually, so these agencies need to be contacted well in advance to
determine their current or projected funding status.
Each State and territory has a designated State Water Resource Research In-
stitute or Center on the campus of at least one land grant university in the State.
In nearly all instances, these units have staff and libraries that can be of great as-
sistance to individuals or groups seeking information about restoration
programs, such as the State agencies involved, the rules and regulations involv-
ing shoreline development, in-stream and lake manipulations, dredging, and ap-
plication of chemicals to lakes. In most instances, they will be aware of
assistance programs to implement a restoration project. Each institution or cen-
ter also has contact with, or directories of, the more prominent lake researchers
and agency personnel of the State.
8-9
-------
Local Funding Sources

In some States, lake management districts have been authorized with enabling
legislation that permits millage or tax assessments. Watershed management dis-
tricts, irrigation districts, conservation districts, or sewer districts may have the
authority to fund watershed management or lake management plans that will im-
prove lake quality. Private foundations might have funds available for particular
aspects of lake management such as nature conservancy (for example, preserv-
ing or enhancing wetlands around a lake) or other considerations.
Local clubs, organizations, or community agencies might provide funds or
sponsor fund-raising activities. For example, if fishing is a desired lake use, local
fishing clubs might be interested in sponsoring a fishing tournament, community
dance, or other activity to raise money. Local activities can raise significant
amounts of money. The small community of Republic, Washington, raised
$25,000 in direct contributions to meet a State matching requirement to fund
studies on nearby Curlew Lake.
For many grants or awards, a fund matching arrangement requires the
recipient to raise a percentage of revenue to qualify. This matching money,
however, does not have to be out-of-pocket cash. Often, in-kind services are
credited with a value in lieu of actual cash. Contributed time at an approved,
audited rate can satisfy the matching requirements. City, county, or State agen-
cies, for example, might provide an in-kind match by filing permit applications,
coordinating public meetings, or monitoring restoration activities or other
aspects of the project.
Once funding sources have been identified, the project can be submitted to
prospective consultants and contractors for bids.
Implementation Requires

Contracts
Invitations to bid can be announced locally, but because lake management is a
specialized area, it is generally better to announce the invitation to bid at the
State or regional level. Various organizations have newsletters that are read by
lake management contractors and consultants, so it is a good idea to also con-
sider placing an announcement in these. One of the requirements that should
accompany the bids by potential contractors or consultants is a list of their
qualifications. In the invitation to bid, a minimum set of qualifications should be
specified as a prerequisite to consideration. Prequalification prevents contrac-
tors from wasting their time submitting bids on projects for which they are not
competitive and reduces the time the lake manager has to spend reviewing bids.
Evaluation of the bids and selection of the contractor should be based on the
quality of the proposed work as well as price. The lowest cost will not always
result in the desired lake quality. A local attorney familiar with engineering con-
tracts can be used to prepare a contract or review the contract submitted by the
individual or firm selected for the project.
The person preparing the contract should consider including a requirement
for a contract bond and liability insurance (see Appendix F). A contract bond
guarantees that the work or implementation of the lake management plan will be
completed in accordance with the contract documents (that is, the lake manage-
ment plan with associated specifications) and that all costs will be paid. Ex-
amples of a bid bond, payment bond, and performance bonds are included in
8-10
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Appendix F. These are examples only. Contact a local attorney to obtain a legal
contract.
Implementation Takes Time
Inclement weather, unanticipated obstacles, and other factors can delay the im-
plementation of the lake management program. Some of these delays may be
unavoidable, but their impact can be minimized. One of the first products the
successful contractor or consultant should deliver is a detailed project schedule
and contingency options for every critical activity. A critical activity is one that
must be completed before another activity can proceed or be finished. As an ex-
ample, a restoration plan that includes dredging will come to a complete stop if
the business of acquiring and preparing an approved disposal site is not begun
early enough. Until the disposal site is ready, nothing can come out of the lake.
Smooth implementation depends on careful scheduling. Not only do critical
activities need to be timed to one another, but convenience, ideal operating con-
ditions, and maximal efficiency also need to be kept in mind. It is better to plan a
project so that dredging coincides with a time of year when usage is low but the
lake is accessible, such as fall or early winter. This will allow for maximum boat-
ing safety as well. Alum treatment can be scheduled (1) for late spring following
the major spring flow to aid in inactivation of new nutrient input, (2) in the fall to
intercept the release of nutrients from decaying macrophytes, or (3) after dredg-
ing to inactivate suspended phosphorus and to reduce exposure of rich sedi-
ments to overlying water columns. Watershed manipulation such as
streambank revetment or levee construction can best be accomplished when
water flow is low. Implementation of streamside management zones should
coincide with the peak growing season so that vegetation can become estab-
lished before winter.
Microcomputer scheduling programs are available to permit daily, weekly, or
monthly tracking of the project's progress. These programs can be revised
quickly to determine the impact of delays on project implementation and re-
schedule other activities to minimize these delays. The lake manager needs to
review these schedules on a weekly basis during peak construction or im-
plementation periods.
The lake manager, contractor, or other interested party should audit the
project's progress and expenditures at least quarterly to assure the budget is
living up to the schedule.
Monthly progress reports should be required for the contractor.
Public Education is Critical

for Sound Lake Management
Public education must begin before implementation ever occurs, but it is par-
ticularly critical during implementation. Various desired lake uses generally are
partially restricted while restoration is in progress. Activities such as shoreline
stabilization, alum treatment, and dredging restrict lake usage. People typically
respond positively when they understand what is occurring and why. People
react negatively when they are uninformed about these same activities.
8-11
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In many States, public meetings are a requirement for lake restoration
projects. Every opportunity should be used to discuss progress in all phases of
lake restoration at lake association and lake homeowner meetings. It is essential
to prepare lake residents and users for what may take place during the im-
plementation phase.
Materials, including slides, films, and videotapes of other lake projects, may
be used to familiarize the public with the type of equipment and procedures that
will be used during lake restoration. NALMS can provide a videotape or slide
show on lake management for use in a public information program.

Postmonitoring is an Integral

Part of Implementation
The greatest current deficiency in lake management is the lack of information on
treatment longevity and effectiveness. Postmonitoring must occur if these are to
be determined.
Results from lake management and restoration projects are not always ob-
vious to the naked eye. Postmonitoring can help identify changes in the lake and
whether or not the trend is toward improvement. If monitoring shows that an im-
provement is not occurring, the data can be used to help diagnose the cause. In
addition, restoration projects can result in a short-lived improvement because
some factor not accounted for in the restoration plan is counteracting the work
that was done. By maintaining a continuing monitoring program, such problems
can be detected as they develop.
Postmonitoring is one of the most cost-effective activities of the entire lake
management program. Postmonitoring, however, is not free; it does cost
money The amount of money is directly related to the number of stations, the
number of samples, the number of variables, and the sampling frequency. The
number of stations and number of depths was discussed in Chapter 3. In
general, for oval or round lakes a single station over the deepest point in the lake
might be satisfactory. Additional stations will be required as the lake or reservoir
becomes more irregular with multiple caves and embayments or much longer
and narrower. ...
The number and type of variables and sampling frequency are prioritized in
Table 8-2 These priority groups are based on the amount of money available for
monitoring. The priority group I that is sampled at the minimum frequency (for
example 4 times per year at spring overturn, summer, fall overturn, and winter)
costs the least amount of money. These variables are labeled as A variables. If
the A variables can be sampled at the minimum frequency and if the lake
manager still has some money in the budget for additional sampling, it is recom-
mended that the frequency of sampling these priority group I variables be in-
creased to include sampling at spring overturn and then monthly until fall
overturn (about 6 times during the growing season) with one winter sample. This
represents the B category. If there is still money available, additional variables
(identified as C variables in priority group II - total phosphorus, chlorophyll-a,
conductivity) should be added to the quarterly samples. Additional funds would
result in the addition of D variables (total nitrogen, turbidity, and pH) with month-
ly sampling of total phosphorus, chlorophyll-a and conductivity during the grow-
ing season. As more money becomes available, additional variables are added
and the sampling frequency increases to biweekly sampling during the growing
season with one winter sample and, finally, to biweekly sampling during the
growing season and monthly during the rest of the year.
8-12
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Table 8-2.—Budget guidance for establishing a monitoring program. To use, price
all items labelled "A". If more funds are available, price all items label-
led B. Continue until budgetory limitations prevent any further prog-
ress through the alphabet.
LAKE MONITORING PROTOCOL
PRIORITY PARAMETER
GROUPS
Secchi Transparency
Temperature
1 Dissolved Oxygen
Water Level
Total Phosphorus
II Total Nitrogen
Chlorophyll-a
Conductivity
Turbidity
PH
III Soluble Reactive
Phosphorus
Nitrogen Species
Suspended Solids
Iron3
Manganese3
IV Macrophyte Map4
Phytoplankton Species5
SAMPLING FREQUENCY1
MINIMUM +1 +2 +3
A
A
A
A
C
D
C
C
D
D
E
E
D
F
F
A
E
E
G
B E
B E
B E
B E
D E
F —
D E
D E
E G
D G
G —
G —
G
F
F
F
F
F
N/A
F
—
(simple)
(Complex)
(bloom forms)
(seasonal composite)
1Sampling frequencies
Minimum = 4 times a year
+ 1 = Minimum and 6 times during growing season
+ 2 = Minimum and 12 times during growing season
+ 3 = 12 times during growing season, plus 6 times during winter
zSprmg overturn only, unless total nitrogen is less than 30 times total phosphorus (TN TP <30)
3For drinking water supplies only
4Simple = photograph, percent of lake surface area covered
Complex = areal coverage by species
5Bloom forms = dominant algae during periods of low transparency
Seasonal composite = pooled sample from throughout the growing season from which common algae
species can be determined
This approach should provide some postmonitoring of all lakes with greater
monitoring effort when funds are available. Regardless of the question asked or
problem addressed, there is no substitute for data. Table 8-3 explains briefly
where samples are taken for commonly measured chemical and physical data.
The reliability of the conclusions drawn from monitoring data is directly re-
lated to the quality of the data. There are well-established and accepted
methods and procedures for chemically analyzing water samples. There are also
well-established and accepted procedures for quality assurance and quality
control of the analyses. It is imperative that whatever laboratory, consultant, or
contractor collects and analyzes these samples uses these accepted methods
and has acceptable quality assurance/quality control procedures. Ask if the
methods used are accepted, standard methods and ask to see the quality as-
surance/quality control results from previous water quality analyses on lakes or
streams. Laboratories that analyze sewage might not be able to analyze lake
water samples because the constituent concentrations may be 100-1000 times
less than sewage. Test kits are appropriate for some analyses but should not be
used for most routine water quality analyses. Water quality analyses cost
money; make sure the quality of the data warrants the cost.
8-13
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Table 8-3.—Long-term monitoring requires proper siting and appropriate selec-
tion of parameters ^
LONG-TERM MONITORING CONSIDERATIONS

SITING
Ambient Water Generally, one site over the deepest part of the lake. Should not be near a
Quality dam, close to shore, or near stream inflows or point source influents. Lakes
with distinctive subbasins, coves, fingers, or multiple inlets may require
additional sampling sites (see Chapter 3)

Budgets Flow rates, water levels, and concentrations can be measured on major tri-
butaries and estimated on minor inflows. Accurate assessment of lake vol-
ume be necessary to account for nonpoint source loading and runoff vol-
ume entering the lake. Nonpoint sources are difficult to monitor; a profes-
sional will base siting on lake-specific hydrology, basin morphometry and
other factors. Reference land-use-based export coefficients can provide a
good first approximation, often sufficient to disguise problems. Budgets
are usually limited to diagnostic studies, but long-term monitoring may be
employed to track success of a restoration project or management technique.

Sources Monitoring sites can usually be limited to major inflowing streams or point
source outfalls to the lake or tributary—particulary near suspected sources
of sediment, nutrients, organic matter, or chemicals. Unless a special
problem or land use exists, rates from these stations can be used to inter-
polate rates from minor inflows. In seepage lakes, groundwater obser-
vation wells may be necessary.
PARAMETERS
Complete Water Samples taken from two depths (1 ft below surface and 2 ft above
Chemistry lake bottom)

The following constituents are commonly measured, but a professional
may recommend additional (or fewer) constituents:
Priority Group
Dissolved oxygen
Total phosphorus
Total nitrogen
pH
Total alkalinity
Turbidity
Total suspended solids
Other Parameters Commonly Measured
Ammonia nitrogen Kjedahl nitrogen
Nitrate-nitrite nitrogen Chlorine
Dissolved phosphorus Calcium
Magnesium Sodium
Potasium Sulfates
lron Manganese
Total dissolved solids Volatile solids
Color
Total
Phosphorus
Sampled at two depths (1 ft below surface, 2 ft above bottom) during late
winter to spring turnover; during growing season sampled at three depths
(surface, bottom, and at top of hypolimnion). Multiple measurements near
the surface are a priority

These parameters are profiled, or recored along a vertical axis (the water
column), from 1 ft below surface and at 3-6 ft intervals to the bottom. Meter
is required to measure pH and conductivity
8-14
Water Temp-
erature
pH
Conductivity
Chlorophyll-a Measured at 1 ft below lake surface, and as important as phosphorus

Secchi Extremely useful and simple measurement; minimal sampling schedule
Transparency can be inexpensively upgraded to weekly sampling with
volunteer observers
-------
Table 8-3.—Long-term monitoring requires proper siting and appropriate selec-
tion of parameters (cont.)

LONG-TERM MONITORING CONSIDERATIONS

OTHER USEFUL MEASUREMENTS
Lake Water Frequency can be increased to weekly observations at low cost by using
Level volunteer observers; volunteer programs to observe water levels during
storm events, however, are difficult to conduct. If intensive sampling is
required for a diagnostic study, automated equipment is generally used

Fish Survey Netting during spawning season, boom shocking after Sept. 1. Electro-
shocking every other year. Gill netting every sixth year. Obtain advice from
State or local agency or fish and wildlife department

Macrophytes Surveyed every third year for abundance and location by species during
peak growing season, late summer

Phytoplankton Water collected at 1 ft depth with water bottle to identify species and gen-
eral abundance

Zooplankton A vertical tow is made with a plankton net for identification and general
bundance

Macro-
invertebrates Sampling is conducted in late winter in the lake and inflowing streams

Watershed Inventory of existing land use with field verification (on-site observation
Map and walking tours). Updated every 3 to 5 years, as necessary, can provide
an excellent record of potential sources both for tracing the origin of prob-
lems and planning to prevent problems
8-15
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CHAPTER 9
Lake Protection and
Maintenance
-------
CHAPTER 9

LAKE PROTECTION AND

MAINTENANCE

Introduction
Fishing, swimming, boating, hiking, watching a sunset or a sunrise over the lake,
and sitting on the shore are all activities that occur in and around lakes. Water at-
tracts people, and it is this uncontrolled attraction that eventually results in the
impairment of these desired uses. This Manual is directed primarily at restoring
these desired lake uses. Obviously, the best solution would have been to
prevent the degradation of these uses from occurring. Now, the object is to
prevent these problems from occurring again once the lake is restored.
This chapter discusses some of the approaches that can be used to protect
and maintain the desired lake uses. These approaches range from informal
backyard discussion of lakeshore maintenance or aquatic weeds to the passage
of laws to protect lakes. The key to lake protection and maintenance in all of the
approaches, however, is public involvement and organization.

Lake Organizations
Many lake associations are organized in response to some lake crisis such as
nuisance weeds, fishkills, foul odors, or watershed development. People recog-
nize that collectively they can accomplish more as an organized group than they
can individually. This same rationale is true for lake protection and maintenance.
Preservation of a lake, its water quality, and the desired lake uses is far more
prudent than restoration, and certainly more cost effective.
The types of lake organizations range from informal meetings of homeowners
to share information about their lake to the passage of enabling legislation to
form special lake districts to protect and improve lakes. Wisconsin lake districts,
for example, have the power to tax, levy special assessments, borrow and bond
9-1
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to raise money, make contracts, and other authority to protect and improve
lakes. The critical element is the formation of the lake association. The protection
and maintenance of lakes depends on the ability of lakefront property owners
and lake users to identify their own interests and form an association to pursue
these interests. There is an excellent pamphlet available from the North
American Lake Management Society titled, Starting and Building an Effective
Lake Association. The first step is to form a steering committee of interested in-
dividuals. If your lake does not have a lake association, you need to identify
several others who share your interest and concerns and form the nucleus of the
lake association. More information is available in the pamphlet mentioned above.
One of the primary purposes of all lake organizations, however, should be
educating the public and promoting increased public involvement in lake
management. The more informed people are about lake problems, alternative
management procedures, and watershed effects, the more intelligent their
decisions will be about selecting and implementing appropriate protection and
maintenance procedures. This information is available from a variety of sources
including many of the sources listed in the previous chapter and Appendix E.
State Department of Natural Resources or Environment, Game and Fish, and
County Extension officials generally are willing to provide written information or
talks to organizations about various aspects of lake or watershed management
practices. Local university professors, consulting firms, or members of environ-
mental groups can discuss ongoing or completed projects at other lakes in the
area. Local, State, and Federal officials also can discuss some of the regulatory
procedures available for protecting and maintaining lakes.
Regulations in Lake and

Watershed Protection and

Management Activities
Reasonable and appropriate regulations can be an important part of a water-
shed-lake protection and management plan. These regulations can be adopted
for three general purposes: (1) protecting the lake by regulating watershed ac-
tivities that cause erosion and pollution problems (the point and nonpoint source
controls discussed in Chapter 5); (2) controlling development to protect the aes-
thetics and benefits of the shoreland; and (3) regulating the lake usage to reduce
conflicts among swimmers, boaters, fishermen, and others (Born and Yanggen,
1972). Some of the most serious lake problems occur because of conflicts
among lake users.
Controlled Development
Many of the same regulatory activities developed for other situations such as
urban areas can be adapted to protect or maintain lake quality. Zoning, for ex-
ample, was developed to minimize conflicts between potentially incompatible
land uses such as heavy industry/commercial areas and residential homes in
urban areas. Zoning also can be used to protect lake quality. Setback zones or
areas typically are used to protect highway corridors. Setback regulations for
piers, boathouses, wharves, and homes can help preserve the shore cover,
vegetation, and aesthetics. Some lake communities have a minimum setback of
9-2
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75-100 feet for all buildings, including homes. A variety of zoning regulations are
available for lake management and protection. Some of these are listed in Table
9-1. Many of these procedures were summarized by Public Technoloav Inc
(1977). ay> '
Table 9-1.—A variety of zoning techniques
TOPIC
DEFINITION
Zoning The regulation of building types, densities, and uses permitted in dis-
tricts established by law.

Special Permits/ Administrative permits for uses that are generally compatible with a
Special Excep- particular use zone, but that are permitted only if certain specified stan-
tions/Conditional dards and conditions are met.
Use Permits
Variances
Floating Zones
Conditional
Zoning
Administrative permits for uses that are generally compatible with a
particular use zone, but that are permitted only if certain specified
standards and condition are met.

Use zones established in the text of a zoning ordinance, but not
mapped until a developer proposes and the legislative body adopts
such a zone for a particular site.

An arrangement whereby a jurisdiction extracts promises to limit the
future use of land, dedicate property, or meet any other conditions. The
arrangement is either stated in general terms in the zoning ordinance or
imposed on a case-by-case basis by the legislative or administrative
body, prior to considering a request for a rezoning.

Contract Zoning An arrangement whereby a jurisdiction agrees to rezone specified land
parcels subject to the landowner's execution of restrictive covenants or
other restrictions to dedicate property or meet other conditions stated in
the zoning ordinance or imposed by the legislative or admini-
strative body.

Cyclical Rezoning The periodic, concurrent consideration of all pending rezoning applica-
tions, generally as part of an ongoing rezoning program, focusing upon
one district at a time.
Comprehensive
Plan
Consistency
Requirement

Zoning
Referendum
Provisions that require all zoning actions, and all other government
actions authorizing development, to be consistent with an indepen-
dently adopted comprehensive plan.
Ratification of legislatively approved land use changes by popular vote,
before such changes become law.
Prohibitory Zoning The exclusion of all multifamily, mobile, modular, industrialized, prefab-
ricated, or other "undesirable" housing types from an entire jurisdiction
orfrom most of the jurisdiction.

Agricultural The establishment of "permanent" zones with large (that is multiacre)
Boning/Large Lot minimum lot sizes and/or a prohibition against all nonagricultural devel-
zoning/Open opment (with the exception of single-family residences and possibly
Space Zoning selected other uses).

Phased Zoning/ The division of an area into (1) temporary holding zones closed to most
Holding Zones/ nonagricultural uses and/or with large minimum lot sizes and (2) ser-
bhort-Term Ser- vice areas provided with urban services and open for development in
vice Area the near term (for example 5 years)
9-3
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Table 9-1.—A variety of zoning techniques (cont.)
TOPIC DEFINITION
Performance An arrangement whereby all or selected uses are permitted in a dis-
Zoning/Perform- trict if they are in compliance with stated performance standards, that
ance Standards is, if they meet stated community and environmental criteria on pollu-
tion, hazards, public service demands, etc.

Flexible Zoning/ Freedom from minimum lot size, width, and yardage regulations,
Cluster Zoning/ enabling a developer to distribute dwelling units over individual lots in
Density Zoning any manner the developer desires, provided (usually) that the overall
density of the entire subdivision remains constant.

Planned development of the lake's watershed is an effective means of mini-
mizing lake problems because of watershed development while maintaining
economic growth in the community. Subdivision regulations including minimum
lot sizes, minimum frontage requirements, minimum floor area, height restric-
tions, and land use intensity ratings also are applicable for lakefront property or
the community around a lake. Several development approaches are listed in
Table 9-2 (Public Technology, Inc.). Planned unit developments allow much
greater flexibility in arranging lots in clusters rather than all along the shoreline
(see Fig. 9-1). Clustering lots in given areas also makes it more economical, and
efficient, for small-scale water systems and waste treatment systems. Planned
unit development can be combined with special protection, critical area, or en-
vironmentally sensitive area designations to provide lots and homes for people
in a lake environment and setting while protecting important environmental
resources such as wetlands, shorelands, groundwater recharge zones, or uni-
que aquatic habitat.
Table 9-2.—A variety of development options
TOPIC DEFINITION
Planned Unit A conditional use or floating zone regulated through specific design
Development standards and performance criteria, rather than through the traditional
(PUD) lot-by-lot approach of conventional subdivision and zoning controls.

Subdivision Procedures for regulating the division of one parcel of land into two or
Regulations more parcels—usually including a site plan review, exactions, and the
application of aesthetic, bulk, and public facility design standards.

Minimum Lot Size The prohibition of development on lots below a minimum size.

Minimum Lot Size A limitation on the maximum number of dwelling units permitted on a lot,
Per Dwelling Lot based on the land area of that lot (usually applied to multifamily housing).

Minimum Lot Size A limitation on the maximum number of rooms (or bedrooms) permitted on
Per Room a lot, based on the land area of that lot (usually applied to multifamily
housing).

Setback, Front- The prohibition of development on lots without minimum front, rear, or side
age, and Yard yards or below a minimum width.
Regulations

Minimum Floor The prohibition of development below a minimum building size.
Area

Height Restriction The prohibition of development above a maximum height.

Floor Area Ratio The maximum square footage of total floor area permitted for each square
(FAR) foot of land area.
9-4
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Table 9-2.—A variety of development options (cont.)
TOPIC
DEFINITION
Land Use Intensity Regulations that limit the maximum amount of permitted floor space and
Rating require a minimum amount of open space (excluding parking areas) and
recreation space, and a minimum number of parking spaces (total and
spaces reserved for residents only).

Adequate Public The withholding of development permission whenever adequate public
Facilities facilities and services, and defined by ordinance, are lacking, unless the
Ordinance facilities and services are supplied by the developer.

Permit Allocation The periodic allocation of a restricted (maximum) number of building per-
System mits or other development permits first to individual districts within ajuns-
diction and then to particular development proposals.

Facility Allocation The periodic allocation of existing capacity in public facilities, especially in
System sewer and water lines and arterial roads, to areas where development is
desired while avoiding areas where development is not desired.

Development A temporary restriction of development through the denial of building
Moratorium/ permits, rezonmgs, water and sewer connections, or other develop-
Interim Develop- ment permits until planning is completed and permanent controls and
ment Controls incentives are adopted, or until the capacity of critically overburdened
public facilities is expanded.

Special Protec- Areas of local, regional, or State-wide importance—critical environ-
tion Districts/ mental areas (for example, wetlands, shorelands with steep slopes);
Critical Areas/ areas with high potential for natural disaster (for example, f loodplains
Environmentally and earthquake zones); and areas of social importance (for example,
Sensitive Areas historical, archaeological, and institutional districts)—protected by a
special development review and approval process, sometimes involv-
ing State-approved regulations.
Permits and Ordinances
Adequate public facilities ordinances and sanitary permits can be used to mini-
mize problems with septic systems or housing growth that exceeds the capacity
of existing waste treatment systems. Sanitary permits can be required prior to
building any structure for human occupancy. Sites that are not suited for septic
systems will not be issued building permits. Ordinances can be developed to
limit building growth to a pace within the capacity of the treatment systems to
adequately handle the increased wasteloads. These ordinances can provide for
the orderly, and timely, expansion of waste treatment facilities to treat the
sewage.
Zoning also can be used to minimize conflicts on the lake (Yanggen, 1983).
Both areal and time zoning can be used to reduce use conflicts by prohibiting
certain uses in selected areas or time of day. For example, certain areas of the
lake could be restricted for particular uses such as swimming or diving (Fig. 9-2).
Power boating and skiing can be restricted to open water areas with fishing
restricted to shore areas. A minimum distance and/or speed also can be
specified; for example, a power boat must be at least 100 feet away from an
anchored fishing boat or moving at no more than 5 mph.
9-5
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Cluster development
Figure 9-1 .-Clustering of lots or homes in the portion of the watershed best suited to devel-
opment reduces problems in the lake and maintains economic development in the water-
shed. The same number of lots can be developed using the cluster approach but water
supply and waste treatment can be more efficient and effective. After Fulton, et al. 1971.
Zoning can be established based on time of day as well as space. For ex-
ample, pleasure motor boating or water skiing could be restricted to the hours of
10 a.m. to 6 p.m. This would minimize conflicts with fisherman. Restrictions of
motor sizes (for example, no motors on some lakes, only electric motors, or only
motors less than 10 hp) are commonly used on small lakes or lakes in pastoral
settings.
All of these regulatory procedures can be combined to provide the most
suitable approach for a particular lake or specific set of lake uses. Regardless of
the regulations or restoration practices employed, however, it is critical that lake
management be an integrated program of watershed and lake management that
is tailored to the particular uses and priority problems of the lake user.
9-6
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Time Zoning
Water-Skiing
10 a.m. to 6 p.m.
Figure 9-2.-Conflicts among multiple users can sometimes be avoided by restricting the
space in which the activities occur or the time of day for these activities. *
Lake Monitoring
Implementing a monitoring program has been discussed in previous chapters. It
is mentioned again to emphasize the importance of monitoring lake changes
through time. It is easier and much more cost effective to treat problems as they
start to develop rather than after these problems have reached a crisis or
nuisance level. Monitoring is the only approach for determining whether protec-
tion and maintenance approaches are effective.
9-7
-------
Lakes are dynamic systems that age through time. As the lake ages, the ef-
ficiency and effectiveness of various management techniques can change.
Monitoring programs can record these changes and indicate (1) the need to
alter the management procedures to maintain the same lake uses or (2) that the
lake no longer can support these uses. Investment precedes dividends; invest-
ing in monitoring pays dividends by ensuring lake management techniques are
providing effective protection or maintenance of the desired lake uses.
Chapter 8 provides guidance for establishing a monitoring program to obtain
the most important information possible based upon financial ability.
9-8
-------
Epilogue
Not many books close by quoting from the Foreword to another book, but this
Manual is not just any book. Just as this final page is not the end at all; it only
punctuates your evolving understanding of lake and reservoir management — in
itself, a continuing, active, iterative process. So, from the foreword to Lake
Management Guide (NALMS, 1987):

Lakes are the geological fireflies. They have a limited lifespan,
at least on a geological basis. Some come and go in a span of a
few hundred years. Even the oldest lakes formed by ancient
shifts in the earth's surface or glacial forces are impermanent.
Occasionally, we can witness the complete death cycle of a lake
in our own lifetimes. Where this happens, man is often impli-
cated.

Restoration and protection projects interrupt two great forces:
nature's compelling pressures and man's habits. The projects in
this book are aimed at correcting our own unhealthy habits. It is
not as simple as stopping and undoing our own past mistakes,
however; whatever man does to nature, nature will amend. If we
cause an imbalance in fish populations toward rough fish, nature
will seek an adjustment from there. If we allow erosion from our
land to fill our lakes, nature will establish new territorial bound-
aries—perhaps favoring a wetland where a lake once existed.

May this Manual be your guide to understanding your lake, the processes
that affect it, and the ways you can protect and, if necessary, restore it. In other
words, may this final page represent a beginning for your lake.
10-1
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Chapter 3
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Chapter 7
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Chapter 9
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ments. Washington, DC.
10-6
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Index
2,4,5-T 6-32
2,4-D 6-26,6-31,6-32
208 Water Quality Management Plans 7-8
activated sludge 5-4, 5-5, 5-9
advisory committee 7-5
aeration of the whole lake 7-28
aerial photographs 3-9, 7-9
aesthetics 1-2, 3-4, 3-6, 7-7
aging 2-21
agricultural practices 7-24
agricultural runoff 6-17
Agricultural Stabilization and Conservation
Service 8-8
Alaska 8-4
algae 3-3,3-4,6-4,6-18
algae biology 6-5
algae control 6-17,7-21
algal 5-3
algal biomass 2-5, 2-15, 3-16
algal blooms 2-15, 3-17, 3-4, 4-2, 5-3, 5-13,
6-6,6-9,6-10,6-11,6-20
algal cells 6-10
algal concentrations 4-19
algal control 6-14,6-17,6-20
algal die-off 3-18
algal growth 3-16, 4-3, 4-19, 4-20, 6-5, 6-10
algal production 2-5
algal productivity 2-15
algicide application 6-2
algicides 2-22,6-17,6-19,7-28
alkalinity 3-11,6-7,7-10
alligatorweed flea beetle 6-26
alternative on-lot treatment methods 5-8
alternative on-lot wastewater 5-7
alternative solutions 8-1
alum 6-6, 6-7, 6-28, 6-36
alum treatment 3-25, 4-21, 7-19, 7-21, 7-26,
7-28,8-11
ammonia 5-6
ammonia nitrogen 7-10,7-12
ammonium nitrogen 3-18
animal waste management 5-16,7-24
Annabessacook Lake 5-20, 5-21
annual cost method 7-21
annual water 7-16
annual water balance 7-17
anoxia 2-6, 2-17, 3-17, 6-17, 7-14, 7-17
aphoticzone 2-14
applicability 7-20
Aquascreen (fiberglass) 6-23
aquatic weed species 6-34
aquatic weeds 6-33
Arizona 8-4
Arkansas 6-25,8-4
artificial aeration/destratification 2-23
artificial circulation 2-22, 6-11,6-12, 6-19,
6-36
atmosphere 2-4, 2-5, 4-11
atmospheric input 2-6
attainable uses 3-5
automated stream monitoring 7-12
automatic water sampler 7-12
bacteria 2-19,5-2
barge 6-28
basin-shape 6-3
bathymetric map 6-21
benefits 7-21
benthic invertebrates 6-23
best management practices 2-7, 5-1, 5-15,
5-16, 5-17, 5-18, 5-19
bid bond 8-10
biochemical oxygen demand 2-5, 3-9, 3-10
bio-filters 5-4
biological controls 6-20, 6-24
biological indicators 3-19
biological productivity 2-7, 2-14, 2-19
biology of macrophytes 6-19
biomanipulation 6-16,6-17
biomass 2-15, 2-22, 3-19
biota 2-1,2-3
bloom frequency 4-3
blooms 6-5
blue-green algae 2-15, 2-16, 3-16, 3-19,
4-22, 6-5, 6-11, 6-18, 6-27, 6-36, 7-3, 7-15
blue-green algal blooms 4-19
blue-greens 6-35
boating 3-3, 3-4, 3-6, 6-3, 6-19, 7-1, 9-1
bond 9-1
borrow 9-1
bottom contours 3-15
budget guidance 8-13
budgets 8-14
buffer strips 5-19,7-24
Bureau of Reclamation 8-9
California 8-4
capital costs 5-8, 5-16, 7-21
carbon dioxide 6-11
Carlson 3-21,4-13
Carlson's Trophic State Index (TSI) 3-21,
3-24,4-13,4-14,7-15
carry-over effect 6-29
case study 7-1
cattails 6-25
causes 1-4, 3-9, 3-11, 2-23, 3-2, 3-3, 3-6
Cesium-137 3-15
change in storage 4-7, 4-9
Chara 6-24, 6-32
Chautauqua Lake, NY 6-29
chemical analyses 3-18
chemical and biological characteristics 7-9
chemical oxygen demand 2-5
chlorophyll 2-13, 3-9, 3-16, 3-19, 4-2, 4-3,
4-12,4-18
chlorophyll-a 4-4, 4-5, 4-13, 4-14, 4-15,
4-17, 4-18, 4-20, 4-21, 4-21, 4-22, 7-11,
7-15, 7-18, 8-13, 8-14
City of Middletown 7-2
Clean Lakes Program 3-8, 7-3, 7-6, 7-8, 8-8
Clean Water Amendments of 1987 8-8
climate 2-23
cluster systems 5-9
clustering lots 9-4
10-7
-------
Cobbossee Lake 5-20, 5-21
cold-water fishery 6-12
color 6-4,6-36
Colorado 8-4
community succession 2-15
community treatment system 5-13
concentrations 4-6, 4-9, 4-16
condition 1-3
conductivity 3-11, 7-10, 8-13, 8-14
confidence 4-5, 5-16, 7-20
conflicts 9-2
conflicts users 6-37
Connecticut 8-4
conservation 5-16
conservation districts 8-10
conservation tillage 5-16, 5-17, 5-19, 7-24
construction controls 7-26
consultant 3-7, 7-4, 7-23, 8-1
consultant selection 7-6, 8-3
consulting 9-2
consumption 2-14
contact stabilization 5-4
contingency options 8-11
continuous streamflow data 7-17
contour farming 5-16
contour stripcropping 5-16
contract bond 8-10
contractor 8-1
contractor selection 8-10
contracts 8-10,9-2
control of macrophytes 6-21
control of nuisance algae 6-12
control of nuisance aquatic weeds 6-35
control strategies 3-9
controlling development 9-2
conventional septic systems 5-8
conventional sewers 5-8
conventional treatment 5-4
coontail 6-22,6-24
copper 6-17,6-37
copper accumulation in sediments 6-18
copper sulfate 5-20, 6-17, 6-33, 7-20
corrective stocking 6-38
cost comparison 6-33, 7-21
cost comparisons for biological controls
6-27
costs 6-32,8-8
costs of algicides 6-18
costs of drawdown 6-23
costs of hypolimnetic aeration 6-13
County Conservation District 7-24
criteria for selecting consultants 8-2
critical area 5-18, 5-19, 9-4
crop rotation 5-16, 7-24
Crustacea 6-32
crustacean 6-14
cultural eutrophication 2-19, 2-21
cultural sources 5-14
cutting 6-20
cutting rates 6-28
Dartek (nylon) 6-23
data 3-8,3-11,7-8
data analysis 7-14
data collection 3-11
decomposition 2-10, 2-16, 2-19
Delaware 8-4
Delphi process 1-4, 3-5
density flows 2-11,2-13
density gradient 2-9
Department of Commerce 8-9
Department of Housing 8-9
depths 4-13,4-21
destratify 6-12,7-14
detention basin 5-16, 5-18, 7-19
diagnosing problems 8-1
diagnosis 3-7, 3-9, 3-10, 3-11
diagnostic models 4-1
diagnostic study 3-24, 7-23
diagnostic/feasibility studies 6-2, 6-3
diatoms 2-15
dilution 5-4,6-10,6-19,6-37,7-28
diquat 6-31,6-33
discharge 5-1
Discharge Monitoring Records 3-9
discharge rates 5-2
discrete cash flow 7-23
disposal sites 6-19,8-11
dissolved oxygen 2-10, 2-19, 3-11, 3-17,
3-26, 3-27, 3-9, 5-2, 5-3, 6-11, 6-23, 7-9, 8-13
dissolved solids 3-18
disturbed area limits 5-16, 5-18
diversion 3-26, 5-20, 5-21, 6-6, 6-36
divert 5-20
domestic wastewater sources 5-13
drain field 5-6
drainage 5-1
drainage basin 6-3, 6-36
drainage lake 2-4
drawdown 6-23,6-35
dredging 3-4, 6-7, 6-19, 6-20, 7-19, 7-20,
7-21,7-26,7-28,8-11
dredging costs 6-9
drinking water 3-4, 6-12, 6-35, 6-36
drying 6-23
dyes 6-23
East Twin Lake 5-21
ecology 2-1
ecoregions 3-6, 3-16, 6-3
ecosystems 2-1,7-21
effectiveness 7-19
effects on lake quality 1-5
elodea 6-25
emergent species 6-34
endothall 6-31
energy 2-17
EPA 6-35,7-5
epilimnion 2-8, 2-9, 2-11,6-13
equivalent annual cost 7-22
erodible soils 6-3
erosion 3-15,5-18,6-18,9-2
erosion control 5-15,6-21, 7-23, 7-26
essential nutrients 2-14
Eurasian watermilfoil 6-22, 6-26
eutrophic 1-2, 2-17, 2-23, 3-17, 4-15, 4-23
eutrophic classification 7-15
eutrophication 1-2,1-5, 2-15, 2-17, 2-19,
2-21,2-22,3-21,4-14,4-15
eutrophication model 4-3, 4-4, 4-5
eutrophy 2-19,2-21
evaluation criteria 7-18
10-8
-------
evaluation matrix 7-23
evaporation 2-4,4-7
export 4-9
export coefficients 3-10,4-9
extension 5-17
external loading 4-20
external loads 7-17
external nutrient loading 2-23
external phosphorus loading 4-20, 7-17
7-18
fall overturn 2-10
Farmers Home Administration 8-9
feasibility study 6-19
fecal coliform 5-21
federal agencies 8-8
Federal Clean Water Act 5-3
fees 8-3
fertilizer management 5-16, 5-17, 5-19
fiberglass 6-23
filamentous algae 6-5, 6-28
Fish and Wildlife Service 8-3
fish management 6-37, 6-38
fish species 6-14
fish survey 8-14
fisheries 6-26
fishing 6-4,9-1
fishkills 2-15, 2-6, 3-4, 3-18, 3-24, 6-18
floating species 6-34
flocculation 4-22
Florida 6-21, 6-25, 6-26, 6-30, 8-4
flow 3-11,3-14,3-18,4-3,4-6,4-12
fluridone 6-32
flushing 4-20, 6-10, 6-19, 7-21, 7-28
flushing rate 4-3, 7-28
food chain 2-17, 2-18, 6-15
food chain manipulation 6-14, 6-19, 7-28
food web 2-7,2-17,6-14
food web manipulation 6-17
Forest Service 8-9
freezing 6-22,6-23
funding 8-4, 8-5, 8-6, 8-7, 8-10
funding sources 8-8
fungi 2-19
gas exchanges 2-10
geology 3-6
Georgia 6-25,8-4
glacial lakes 2-20
glaciation 2-20
glyphosate 6-32
granulated active carbon 6-36
grass carp 2-23, 6-25, 6-26, 6-27, 6-31,
6-32, 6-33, 6-35
grassed waterways 5-16, 5-18, 7-20
gravity sewers 5-4
grazers 6-14,6-20
grazing 6-17
Great Lakes 2-12
groundwater 2-20, 2-4, 3-10, 3-11,3-12,
3-24, 3-9, 4-7, 4-8, 5-8, 5-21, 7-11, 7-17
groundwater observation well 3-13
groundwater recharge zones 9-4
growth rates 6-25
growth rates of macrophytes 6-19
habitat(s) 2-2, 2-7, 2-20
harvesting 2-22, 2-23, 3-4, 6-21, 6-28, 6-32,
6-33, 6-35, 6-37
harvesting costs 6-30
Hawaii 8-4
heavy metals 5-15,6-9
herbicides 2-22, 3-4, 6-2, 6-20, 6-21, 6-29,
6-30, 6-31, 6-32, 6-33, 6-34, 6-35
holding 5-8
homeowners 9-1
hydraulic dredge 6-7
hydraulic residence time (see also residence
time) 2-5, 2-3, 2-7, 2-8, 2-14, 2-21,
2-23, 3-10, 4-12, 4-16, 4-17, 4-20, 4-22, 7-14
hydrilla 6-25,6-27
hydrologic 4-22
hydrologic cycle, the 2-4
hydrology 2-23, 4-4, 4-7, 4-4, 4-7, 4-12
hypereutrophic 4-15, 4-16, 4-19, 4-23
hypereutrophy 2-19,2-21
hypolimnetic aeration 2-22, 6-12, 6-19, 7-28
hypolimnetic aerators 5-20
hypolimnetic dilution 2-22
hypolimnetic flushing 2-22
hypolimnetic withdrawal 2-22, 6-13, 6-19
hypolimnion 2-8,2-11,4-21,6-12
Idaho 8-4
Illinois 8-4
impaired uses 3-1, 3-3
implementation 8-1,8-11
implementation costs 8-8
Implementing the restoration program 7-5
Indiana 8-4
infilling 3-4
infiltration 2-4
inflow 4-7, 4-13, 4-16, 4-17
inflow concentration 4-22
inflowing stream 3-9
in-kind services 7-7
in-lake management 7-26
in-lake procedures 6-4
in-lake technique effectiveness 6-4
insects 6-25, 6-26, 6-35
integrated pest management 5-16, 5-17
integrated sample 3-15
interactions 3-6
interception or diversion practices 5-16
internal loading 3-24, 6-6
internal nutrient cycling 6-18
internal nutrient loading 2-22, 2-23
Iowa 8-4
iron 6-36, 7-10, 8-13
irrigation districts 8-10
Kansas 8-5
Kentucky 8-5
kettle lakes 2-20
Kezar Lake, NH 4-17, 4-20
Kimmel Creek 7-2
laboratories 8-13
LaDue Reservoir 6-29
lagoons 5-4, 5-5, 5-9
lakes 1-2
lake and watershed characteristics 7-7
lake associations 2-1,3-5,3-7,5-1,5-15
5-19,7-1,9-1
Lake Baldwin, FL 6-27
lake basin 2-20, 2-23
10-9
-------
lake budget 3-10
lake conditions, factors in 2-3
Lake Conroe, TX 6-25
Lake Evaluation Index 3-23
lake level 3-11
Lake Lillesjon 6-14
Lake Lillinonah, CT 4-17, 4-22
lake maintenance 9-1
lake management 2-22, 3-6, 3-26, 5-13
lake management program 5-1
lake mixing 2-12
lake monitoring 7-9
Lake Morey, VT 4-9,4-10,4-17,4-21
lake organizations 9-1
lake phosphorus 4-17
lake problems 3-1, 3-6, 3-8
lake production 2-11
lake protection 9-1
lake response models 4-12
lake restoration 2-22, 6-2, 6-19, 7-4, 8-2, 8-3
lake sediments 6-22
lake shape 2-20, 2-23, 4-5
Lake Superior 2-21
lake systems 2-1,5-1
Lake Trummen, Sweden 6-8
lake types, desired use 3-5
lake types, specific uses 3-5
lake usage 8-11
lake users 3-5, 3-6, 3-8
lake uses 2-8, 3-4, 6-3
lake volume 3-4,4-12
Lake Washington, WA 4-17,5-4,5-20
lake water level 8-14
lake's basin 6-3
land use 3-6, 3-9, 3-10, 4-21, 5-2, 5-15,
5-16, 7-23, 8-14
leach field 5-21
Lead-210 3-15,3-24
liability insurance 8-10
licensed 31
light 2-16, 3-16, 3-22, 4-20, 6-5, 6-11, 6-20
light penetration 2-7,2-16
lime 6-14
limited lake monitoring 7-7
limited watershed monitoring 7-7
limnology 2-3, 3-7, 8-2
littoral zone 2-7
livestock exclusion 5-16
loading 3-9, 3-10, 4-4, 4-5, 4-6, 4-12, 4-18,
4-19,5-11,6-3,6-36,7-17
loading estimates 4-7
local initiative 3-5
Long Lake, WA 4-17, 4-20
longevity 5-16, 7-20
loss of storage capacity 37
Louisiana 8-5
Lynn Lake 7-1
macroinvertebrates 8-14
macrophyte control 3-9, 6-9, 6-26
macrophyte growth 5-3
macrophyte map 8-13
macrophyte production 2-17
macrophyte survey 3-20, 7-11
macrophytes 2-7, 2-11, 3-4, 3-8, 3-19, 4-3,
5-3,6-4,6-19,6-33,7-1,8-14
macrophytes, species 3-20
Maine 8-5
management 3-6,3-24
management plan 5-18,7-29,8-1
management practice 7-19, 7-20, 7-23
management techniques 6-1,6-19
manganese 6-36, 7-10, 8-13
man-made causes 3-7
man-made sources 2-6
marshes 6-37
Maryland 8-5
Massachusetts 8-5
matching grant 7-8
maximum depth of colonization (MDC)
6-20, 6-21
maximum depths 7-14
mean depths 4-17,7-14
mesotrophic 4-15, 4-23,
mesotrophy 2-19,2-21
metalimnion 2-8,2-11,4-21
metric system 1-1
metric units 4-2
Metropolitan Seattle 4-18
Michigan 8-5
microcomputer scheduling programs 8-11
Middletown Sewer Authority 7-8
milfoil 6-29
minimum distance 9-6
minimum speed 9-6
Minnesota 8-5
Mirror Lake 3-24, 3-25, 3-27
Missouri 8-5
mixed layer 4-5, 4-21
mixing 2-8, 2-9, 3-15, 3-17, 3-24, 3-26, 6-11
model capabilities 4-16
model predictions 4-5, 4-20
modeling 3-18,4-18
models 3-7,4-1,4-2,4-13,4-23
monitoring 3-22, 4-2, 4-5, 4-23
monitoring data 8-13
monitoring program 4-6, 5-18, 8-12, 8-13,
9-7
Montana 8-5
morphometry 4-12
mound systems 5-7
multiple purposes 2-8
multiple uses 1-3
municipal treatment systems 5-3
murkiness (see "turbidity")
National Oceanic and Aeronautic
Administration 7-14
National Pollutant Discharge Elimination
System 5-2
National Science Foundation 6-4
natural background 6-3
natural causes 3-7
natural conditions 1-2, 2-19, 2-23, 3-6
natural vegetation 5-18
Nebraska 8-6
net sedimentation 4-10
Nevada 8-6
New Hampshire 8-6
New Jersey 8-6
New Mexico 8-6
New York 8-6
10-10
-------
nitrate 3-18,7-10
nitrate nitrogen 7-12
nitrogen 2-14, 3-18, 4-4, 5-6, 6-17, 7-10
nitrogen budgets 7-17
nitrogen removal 5-4
nitrogen species 8-13
nominal group 1-4
nominal group process 3-5
nonpoint sources 5-1, 5-13, 5-15, 5-16,
5-18,5-19,6-3
nonvegetative soil stabilization 5-19
North American Lake Management Society
(NALMS) 7-4, 8-2, 9-2
North Carolina 6-25, 8-6
North Dakota 8-6
North Twin Lake 3-19
Northern lakes 4-13
nuisance algae 6-4
nutrient 3-5, 6-33, 7-3
nutrient budget 3-24,5-12,7-16
nutrient concentrations 5-4, 5-14, 6-7
nutrient control 2-22,5-15
nutrient cycling 2-17, 2-19
nutrient diversion 6-36
nutrient enrichment 2-21
nutrient income 3-18, 3-24
nutrient levels 7-20
nutrient loading 2-6, 2-21, 3-7, 3-11,4-1,
5-3,7-11,7-12,7-14
nutrient losses 5-17
nutrient recycling 2-22, 4-21
nutrient release 6-8
nutrient removal 6-29
nutrient supply 2-4
nutrients 2-5, 2-14, 2-19, 3-3, 3-9, 3-11,
3-14, 3-18, 5-2, 5-3, 5-15, 5-18, 6-5, 6-13,
6-20, 6-29
nutrients release 5-3
nylon 6-23
observed responses 4-18
odors 2-6, 2-15, 3-4, 3-8, 3-19, 5-3, 6-4, 6-36
Office of Education 8-9
Office of Mining Reclamation 8-9
Ohio 8-6
Oklahoma 8-6
oligotrophic 2-17, 2-23, 3-6, 4-15, 4-16
oligotrophy 2-19,2-21
on-lot septic systems 5-5
on-lot systems 5-4,5-13
on-lot treatment systems 5-8
Onondaga Lake, NY 4-17, 4-18
onsite treatment and collection 5-4
operational and maintenance costs 5-16
ordinances 5-18,9-6
Oregon 8-6
organics 6-4,6-33
organic loads 5-3
organic matter 2-7, 5-2, 5-4, 5-18, 6-17, 6-18
organic matter consumption 2-11
organic matter decomposition 2-16
organic matter production 2-11
organic nitrogen 7-1
OSHA requirements 8-3
outflow 4-7
outlets 2-11
overland flow treatment 5-5
oxidation ditch 5-5
oxygen 2-5, 2-14, 2-16, 2-17, 3-3, 6-16
oxygen demand 5-4
oxygen depletion 2-10, 2-15, 2-16, 3-18,
5-2, 6-18
oxygen production 2-5
oxygen-demanding 5-3
particulates 2-7
pasture management 7-24
payment bond 8-10
pelagic zone 2-7
Pennsylvania 8-6
perception 3-5,4-14
performance bond 8-10
permits 6-9, 6-14, 8-3, 9-6
permit responsibility 8-3
pesticide 5-15,6-30
pesticide management 5-19
pesticide/herbicide management 5-16
pH 3-11, 6-7, 6-11, 6-16, 7-10, 8-13, 8-14
pH shift 6-7
Phase I Diagnostic/Feasibility Studies 3-8,
7-5, 7-6, 8-8
Phase I Grant Application 7-8
Phase II Lake Restoration Program 3-8, 7-5,
7-6, 8-8
phosphorus 2-14, 3-9, 3-10, 3-18, 3-21, 4-3,
4-4, 4-5, 4-12, 4-13, 6-10, 6-36
phosphorus balance 4-21
phosphorus budget 3-24, 4-6, 4-10, 4-12,
4-16, 4-22
phosphorus concentration 4-16, 4-18, 4-20,
4-22, 4-23, 5-4, 6-5
phosphorus inactivation 2-22, 3-26, 6-6,
6-12,6-19,6-21,6-37
phosphorus income 3-18
phosphorus loading 4-3, 4-15, 4-20, 4-23,
7-14
phosphorus loading models 4-3
phosphorus precipitation 2-22, 6-5, 6-6,
6-14
phosphorus release 4-20,6-5,7-14
photic zone 2-14,3-19
photosynthesis 2-11, 2-14, 2-16, 2-17, 2-19,
4-13,6-17
physical characteristics 7-9
phytoplankton 2-11, 2-14, 2-15, 6-5, 6-16,
7-11,7-15,8-14
phytoplankton community 2-16
phytoplankton species 8-13
Pickerel Lake 3-16
plankton 2-16
planktonic algae 6-18
planned development 9-4
planning 8-2
plant density 3-20
plant growth 6-2
plant production 2-19, 2-22
plant species 6-31
plastics 6-23
Pleasant Pond 5-20, 5-21
point sources 4-7, 4-8, 5-2, 5-13, 5-20, 7-17
point-source controls 4-2
point-source diversion 5-20
10-11
-------
pollutant loadings 7-23
pollutant sources 7-9
polyethylene 6-23,6-24
polyprophylene 6-23
ponds 5-9
pondweeds 6-22,6-25
porous cover maintenance 5-16
postmonitoring 8-8,8-12
postrestoration 8-8
Potamogeton 6-24,6-32
potential negative impacts 7-21
potential sources 8-14
pothole lakes 2-20
power to tax 9-1
precipitation 4-7, 4-8, 4-22, 6-3
predator 6-16
predatory fish 2-17
predevelopment runoff rate 7-26
predicted responses 4-18
predictive models 4-1
prequalification 8-10
pressure sewer 5-9
pretreatment 5-5
previous uses 7-9
pricing 8-8
primary producers 2-17
primary production 2-13, 2-21
primary wastewater 5-4
priority 7-23
priority problems 9-7
problem 1-3,3-1,3-23
problem definition 7-3
problem diagnosis 3-2, 3-8
problem identification 2-22, 3-5, 5-18
problem perception 3-5
problem sources 5-19
producers 2-17
productivity 2-4,2-20
project schedule 8-11
propagation 6-19
public access 7-9
public education 8-11
public input 7-6
public meetings 8-12
public opinion 7-4
Public Technology, Inc. 9-3
rain event samples 7-12
range and pasture management 5-16
recreational characteristics 7-7,7-9
recreational uses 7-28
regulating watershed activities 9-2
reservoir restoration 4-20
reservoirs 2-8, 2-11, 2-13, 2-17, 3-6, 3-15,
4-23, 6-3, 6-17, 6-20, 6-27, 6-36
residence time 2-4
respiration 2-10, 2-11, 2-14, 2-16, 2-19
responses 4-19,4-20
restocking 6-37
restoration 4-16, 4-21, 6-1, 6-4
restoration case histories 4-17
restoration techniques 6-36
Rhode Island 8-6
rip rapping 5-18
riparian zone management 5-16
RIPLOX 6-14
road and skid trail management 5-16
rooted plant species 6-22, 6-28
rototilling 6-20
rough fish removal 6-19
runoff 2-3, 3-9, 4-6, 4-8, 4-9, 5-14, 5-15,
5-17, 5-2, 6-9
runoff coefficients 3-10
runoff control 5-15
runoff control ordinance 7-26
runoff diversion 7-24
Rural Clean Water Program 8-9
sampling 3-14,3-15
sampling frequencies 8-13
sand filters 5-5, 5-7
sanitary permits 9-6
scheduling 8-11
Secchi 3-9,4-17
Secchi depth 3-16, 3-17, 4-16, 6-16, 7-10
Secchi disk 3-21,6-20
Secchi transparency 4-13, 6-21, 8-13, 8-14
secondary treatment 5-4
Secretary of the Interior 8-3
sediment 2-3, 2-7, 2-21, 3-3, 8-3
sediment budget 7-11,7-17
sediment cores 2-21
sediment covering material 6-24
sediment covers 6-23, 6-35
sediment loading 3-4, 3-11, 3-15, 7-12, 7-14
sediment nutrient release 6-3
sediment oxidation 2-22, 6-14, 6-19, 7-28
sediment phosphorus release rates 4-20
sediment removal 2-22, 6-7, 6-8, 6-19, 6-20,
6-21,6-35,6-37
sediment sample parameters 7-11
sediment tilling 6-20
sedimentation 2-7, 2-16, 2-19, 3-11,3-15,
4-8, 4-20, 4-8, 4-9, 4-22, 6-4
sedimentation basins 5-16, 5-18, 7-19,
7-20, 7-23, 7-24, 7-26
sediments 2-1,2-16, 3-24, 4-6, 4-16, 4-20,
5-15,6-2,6-3,6-32,7-14
sediments covering 6-23
sediments loads 3-11
sediments removal 6-9
seepage lakes 2-4, 3-12, 4-7
selecting a consultant 7-5, 8-2
septic system 3-10, 3-11, 5-2, 5-6, 5-8
septic tank 3-11, 4-8, 4-9, 5-5, 5-6, 5-21
septic tank diversion 5-21
septic tank input 2-6
septic tank maintenance schedule 5-7
septic tank mound system 5-5
setback zones 9-2
sewage 5-2
sewer districts 8-10
sewerage hookup 7-29
sewering 4-22
shading covers 6-23
Shagawa Lake, MN 4-17, 4-20, 6-5
shallow nonstratified lakes 6-6
shallowness 6-4,6-18
shoreline stabilization 8-11
silt 2-7, 2-16, 5-18, 6-18
slopes 5-6, 5-8, 5-18
sludge 5-5
10-12
-------
small fish 6-17
small-diameter gravity sewers 5-8
small-scale treatment 5-8
small-scale treatment plants 5-4
soft-water lakes 6-7
soil 2-7, 5-7, 5-8
soil absorption 5-5
soil conditions 7-23
Soil Conservation Service 7-7, 7-18, 7-24,
8-9
soil erosion 3-4,5-17
soil loss 2-7
soil types 5-17
soils 2-6, 3-5, 3-6, 5-5, 5-6
soil water tables 5-6
soils, fertile 2-21, 2-23, 3-6
solids 5-7
soluble reactive phosphorus 7-10, 7-12,
8-13
sources 5-12,8-14
South Carolina 8-7
South Dakota 8-7
space zoning 7
spatterdock 6-25
special assessments 9-1
special protection 9-4
spills 6-36
spring turnover 6-13
staff gage 3-11
standard methods 8-13
state agencies 8-2, 8-9
State Department of Game 8-3
State Water Research Institute Program 8-9
states lake programs 8-4, 8-5, 8-6, 8-7
stilling well 3-11,3-12
stocking rates 6-26
storm sewers 3-24
stratification 2-8, 2-11,3-15, 3-17, 4-21
stratified 2-17,6-6
stratified lakes 3-15
stream gaging 3-11
stream hydrograph 7-12
stream inflow 3-9
stream loadings 4-8
streambank stabilization 5-16,5-18
streamside management 8-11
streamside management zones 5-16,5-18
street cleaning 5-9
subdivision regulations 9-4
submerged species 6-34
submergent 6-20
surface area 4-17
surface roughening 5-16,5-18
surface shading 6-24
suspended sediment 2-7
suspended solids 8-13
swimming 3-3, 3-4, 3-6, 4-14, 6-3, 6-37, 7-1,
9-1
symptoms 1-4, 2-23, 3-2, 6-2
tables 5-8
taste 2-15,3-4,3-8,3-19,6-4,6-36
temperature 3-11, 3-15, 7-9, 7-10, 8-13
Tennessee 8-7
terraces 5-16
tertiary treatment 5-4, 7-26, 7-28
test kits 8-13
Texas 6-25,8-7
thermal destratification 6-14
thermal stratification 2-7, 2-8, 2-10, 2-12,
5-2,6-11,6-13
thermocline 2-8, 2-10, 2-11, 4-4
THM's 6-35,6-37
time zoning 7
topography 7-23
total Kjeldahl 3-18
total nitrogen 3-18,7-12,8-13
total phosphorus 4-14, 6-9, 7-10,7-12, 8-13,
8-14
total solids 3-18
total soluble phosphorus 3-18
total suspended solids 7-10,7-12
toxic controls 5-15
toxic materials 6-36
toxicity 6-32
transparency 3-11, 3-16, 3-22, 4-2, 4-3, 4-4,
4-5,4-12,4-14,4-18,6-6
transpiration 2-4
trapping ability 2-7
treatment plant capacity 5-8
treatment plant upgrade 7-23
treatment systems 5-3
tributary 2-3, 2-8, 4-7, 4-8, 5-2, 6-2
trickling filters 5-5, 5-9
trihalomethane 3-4, 6-28, 6-35, 6-37
triploid grass carp 6-27
trophic level 2-17
trophic state 4-3
trophic state indices 3-7,3-11,3-21
trophic status 2-17
turbid 3-4, 4-4, 4-14, 5-13, 6-9
turbid lakes 6-20
turbidity 2-7, 3-6, 5-3, 6-4, 6-27, 8-13
turnover 2-17
U.S. Army Corps of Engineers 6-8,6-19,
6-37, 8-3
U.S. Department of Agriculture 8-8
U.S. Environmental Protection Agency 8-8
U.S. EPA Clean Lakes grant 7-3
U.S. EPA's Clean Lakes Program 6-4
U.S. Fish and Wildlife Service 8-9
U.S. Geological Survey (USGS) 7-9, 8-9
underdesign 5-6,5-7
university 9-2
usage 5-8
user 9-2
user conflicts 3-1,3-4
user perception 3-6
user survey 7-3
users 1-4, 6-3, 9-7
Utah 8-7
vacuum sewer system 5-8, 5-9
variability 4-5
vegetative stabilization 5-16, 5-18
Vermont 8-7
Virginia 8-7
volcanism 2-20
Vollenweider 4-17
Vollenweider Phosphorus Loading Diagram
7-18
10-13
-------
Wahnbach Reservoir, W. Germany 4-17,
4-22
Washington 8-7
waste disposal 3-14
waste management 5-21
waste treatment facilities 9-6
wastewater 5-2,5-4,5-5,5-6, 5-8
wastewater discharge 2-6, 3-10, 3-11, 5-4,
5-11
wastewater input 2-6
wastewater treatment 2-15, 5-3, 5-4, 5-10
wastewater treatment plants 3-10
water 4-6
water, physical & chemical properties of
2-12
water, temperature-density relationship of
2-12
water balance 2-4, 4-7
water budget 3-24, 4-7, 4-10, 4-12, 5-12
water chemistry 8-14
water column 2-8, 2-9, 4-6, 4-9
water conservation 5-11,5-12
water control 6-21
water density 2-12
water depth 7-11
water hyacinth 6-30
water hyacinth weevil 6-26
water incomes 3-24
water level 3-18,8-13
water level changes 7-12
water level drawdown 6-22
water lily 6-25
water quality 2-11, 4-5, 8-14
water quality monitoring 3-14
water sample 7-10
water stage recorder 3-12
water supply reservoirs 6-35, 6-36
water table 3-10, 3-12, 3-13
water temperature 8-14
water-level drawdown 2-22
water-level fluctuation 2-7
watershed 2-1, 2-2, 2-3, 2-5, 2-22, 2-23, 3-7,
3-9,4-21,5-1,5-2,5-14,5-18
watershed, fertility 2-6
watershed, loadings 4-22
watershed, undisturbed 3-7
watershed analysis 7-16
watershed area 3-5,3-12
watershed characteristics 7-9
watershed development 4-2
watershed district 5-21
watershed disturbance 2-6, 2-21
watershed influences 2-21
watershed management 6-2, 7-23
watershed management districts 8-10
watershed management practices 5-19
watershed manipulation 8-11
watershed map 8-14
watershed monitoring 7-11
watershed to lake area ratio 2-23, 5-12,
5-15,5-18
waterways 7-24
weed disposal 6-28
weed harvesting 7-28
weeds, see "macrophytes"
West Twin Lake 5-21
West Virginia 8-7
wetlands 5-3,9-4
wind 2-8
winter drawdown 6-23
Wisconsin 6-21,8-7,9-1
work 7-8
work plan 7-5
Wyoming 8-7
zoning 5-18,5-19,9-2
zoning regulations 9-3
zooplankton 2-15, 2-16, 3-22, 4-4, 6-14,
6-16,6-17,6-38,7-11,8-14
10-14
-------
Appendix A
APPENDIX A

METRIC UNITS

COMMON UNITS OF MEASURE IN LAKE MANAGEMENT
Limnology, the primary science upon which lake management is based, uses metric
units in professional publications. Although most units in this Manual are expressed in
British/U.S. form, the reader is strongly encouraged to become more comfortable with
common metric units—they are far easier to manipulate, and any further encounter with
the literature and books on lake management will entail the metric system of measurement.
The following table compares the two systems; to convert English units to metric, use
the conversion factors supplied in this table.

METRIC TO ENGLISH CONVERSIONS
METRIC UNIT
LENGTH
Millimeter
Centimeter
Meter
Kilometer
WEIGHT
Microgram
Milligram
Gram
Kilogram
VOLUME
Milliliter
Liter
Kiloliter
(cubic meter)
SYMBOL

mm = 0.001 m
cm = 0.01 m
m = 1.0m
km = 1000m

ug = 0.000001 g
mg = 0.001 g
g = tog
kg = 1000 g

ml = 0.001 L
L = 1.0 L
kl = 1000 L
(m3)
ENGLISH UNIT

inch
inch
yard
mile

CONVERSION FACTOR*

0.03937
0.3937
1.094
0.6214

(no reasonable equivalent)
grain 0.015432
ounce(avoir) 0.03527
pound 2.205

ounce
quart
cu.yard

29.57
1.057
1.308
• To convert metric to English multiply by factor
OTHER USEFUL CONVERSIONS
1 gallon = 3.785 liters
1 milligram/liter = 1 part per million
1 hectare = 2.47 acres
1 acre-foot = 32,590 gallons
1 cubic meter = 264 gallons
A-1
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Appendix B
GLOSSARY
Adsorption: The adhesion of one substance to the surface of another; clays, for
example, can adsorb phosphorus and organic molecules.

Aerobic: Describes life or processes which require the presence of molecular
oxygen.

Algae: Small aquatic plants which occur as single cells, colonies, or filaments.

Allochthonous: Materials (e.g., organic matter and sediment) which enter a lake
from atmosphere or drainage basin; see autochthonous.

Anaerobic: Describes processes that occur in the absence of molecular
oxygen.

Anoxia: A condition of no oxygen in the water. Often occurs near the bottom of
fertile stratified lakes in the summer and under ice in late winter.

Autochthonous: Materials produced within a lake; e.g. autochthonous organic
matter from plankton versus allochthonous organic matter from terrestrial
vegetation.

Bathymetric map: A map showing the bottom contours and depth of a lake.
Can be used to calculate lake volume.

Benthos: Macroscopic (seen without aid of a microscope) organisms living in
and on the bottom sediments of lakes and streams. Originally, the term
meant the lake bottom, but it is now applied almost uniformly to the animals
associated with the substrate.

Biomass: The weight of biological matter. Standing crop is the amount of
biomass (e.g., fish or algae) in a body of water at a given time. Often
measured in terms of grams per square meter of surface.

Biochemical oxygen demand (BOD): The rate of oxygen consumption by or-
ganisms during the decomposition (= respiration) of organic matter, ex-
pressed as grams oxygen per cubic meter of water per hour.

Biota: All plant and animal species occurring in a specified area.
B-1
-------
Chemical oxygen demand (COD): Nonbiological uptake of molecular oxygen
by organic and inorganic compounds in water.

Chlorophyll: A green pigment in algae and other green plants that is essential
for the conversion of sunlight, carbon dioxide, and water to sugar. Sugar is
then converted to starch, proteins, fats, and other organic molecules.
Chlorophyll-a: A type of chlorophyll present in all types of algae, sometimes in
direct proportion to the biomass of algae.

Cluster development: Placement of housing and other buildings of a develop-
ment in groups to provide larger areas of open space.
Consumers: Animals that cannot produce their own food through photosyn-
thesis and must consume plants or animals for energy (see producers).
Decomposition: The transformation of organic molecules (e.g., sugar) to inor-
ganic molecules (e.g., carbon dioxide and water) through biological and non-
biological processes.
Delphi: A technique that solicits potential solutions to a problem situation from a
group of experts and then asks the experts to rank the full list of alternatives.
Density flows: A flow of water of one density (determined by temperature or
salinity) over or under water of another density (e.g., flow of cold river water
under warm reservoir surface water).

Detritus: Nonliving dissolved and paniculate organic material from the metabo-
lic activities and deaths of terrestrial and aquatic organisms.

Drainage lakes: Lakes having a defined surface inlet and outlet.
Drainage basin: Land area from which water flows into a stream or lake (see
watershed).
Ecology: Scientific study of relationships between organisms, and their environ-
ment. Also, defined as the study of the structure and function of nature.
Ecosystem: A system of interrelated organisms and their physical-chemical en-
vironment. In this manual, the ecosystem is usually defined to include the
lake and its watershed.
Environment: Collectively, the surrounding conditions, influences, and living
and inert matter which affect a particular organism or biological community.
Effluent: Liquid wastes from sewage treatment, septic systems, or industrial
sources that are released to a surface water.
Epilimnion: Uppermost, warmest, well-mixed layer of a lake during summertime
thermal stratification. The epilimnion extends from the surface to the ther-
mocline.

Erosion: Breakdown and movement of land surface, which is often intensified
by human disturbances.
Eutrophic: From Greek for "well-nourished," describes a lake of high photosyn-
thetic activity and low transparency.

Eutrophication: The process of physical, chemical, and biological changes as-
sociated with nutrient, organic matter, and silt enrichment and sedimentation
of a lake or reservoir. If the process is accelerated by man-made influences, it
is termed cultural eutrophication.
Fall overturn: The autumn mixing, top to bottom, of lake water caused by cool-
ing and wind-derived energy.
B-2
-------
Fecal coliform test: Most common test for the presence of fecal material from |
warm-blooded animals. Fecal coliforms are measured because of con-
venience. They are not necessarily harmful, but indicate the potential
presence of other disease-causing organisms.

Flood plain: Land adjacent to lakes or rivers which is covered as water levels
rise and overflow the normal water channels.

Flushing rate: The rate at which water enters and leaves a lake relative to lake
volume, usually expressed as time needed to replace the lake volume with in-
flowing water.

Flux: The rate at which a measurable amount of a material flows past a desig-
nated point in a given amount of time.

Forage fish: Fish that are prey for game fish, including a variety of panfish and
minnows.

Food web: pattern of production and consumption of organic matter in an
ecosystem. Green plants are an ultimate source of energy for all food chains.

Ground water: Water found beneath the soil surface and saturating the stratum
at which it is located; often connected to lakes.

Hard water: Water with relatively high levels of dissolved minerals such as cal-
cium, iron, and magnesium.

Hydrologic cycle: The circular flow or cycling of water from the atmosphere to
the earth (precipitation) and back to the atmosphere (evaporation and plant
transpiration). Runoff, surface water, groundwater, and water infiltrated in
soils are all part of the hydrologic cycle.

Hydrographic map: A map showing the location of areas or objects within a
lake.

Hypolimnion: Lower, cooler layer of a lake during summertime thermal
stratification.
Influent: A tributary stream.

Internal nutrient cycling: Transformation of nutrients such as nitrogen or phos-
phorus from biological to inorganic forms through decomposition occurrina
within the lake itself.

Isothermal: The same temperature throughout; fall overturn.

Lake district: A special purpose unit of government with authority to manage a
lake(s), and with financial powers to raise funds through mill levy, user
charge, special assessment, bonding, and borrowing. May or may not have
police power to inspect septic systems, regulate surface water use or zone
land.

Lentic: Relating to standing water (versus lotic, running water).

Limnology: Scientific study of fresh water, especially the history, geology biol-
ogy, physics, and chemistry of lakes. Also termed freshwater ecology.

Littoral zone: That portion of a water body extending from the shoreline
lakeward to the greatest depth occupied by rooted plants.

Macroinvertebrates: Aquatic insects, worms, clams, snails, and other animals
visible without aid of a microscope which may be associated with or live on
substrates such as sediments and macrophytes. They supply a major portion
of fish diets, and consume detritus and algae.
B-3
-------
Macrophytes: Rooted and floating aquatic plants, commonly referred to as
waterweeds. These plants may flower and bear seed. Some forms, such as
duckweed and Coontail (Ceratophyllum) are free-floating forms without roots
in the sediment.
Mandatory property owners association: Organization of property owners in a
subdivision or development with membership and annual fee required by
covenants on the property deed. Association will often enforce deed restric-
tions on members' property and may have common facilities such as bath
house, clubhouse, golf course, etc.
Marginal zone: Area where land and water meet at the perimeter of a lake. In-
cludes plant species, insects, and animals that thrive in this narrow, special-
ized ecological system.
Metalimnion: Layer of rapid temperature and density change in a thermally
stratified lake. Resistance to mixing is high in the region.

Morphometry: Relating to a lake's physical structure (e.g. depth, shoreline
length).
Nekton: Large aquatic and marine organisms whose mobility is not determined
by water movement-for example fish and amphibians.

Nominal group process: A process of soliciting concerns/issues/ideas from
members of a group and ranking the resulting list to ascertain group
priorities. Designed to neutralize dominant personalities.
Nutrient: An element or chemical essential to life, including carbon, oxygen,
nitrogen, phosphorus, and others.

Nutrient budget: Quantitative assessment of nutrients (e.g. nitrogen or phos-
phorus) moving into, being retained in and moving out of an ecosystem;
commonly constructed for phosphorus due to its tendency to control lake
trophic state.
Nutrient cycling: The flow of nutrients from one component of an ecosystem to
another, as when macrophytes die and release nutrients that become avail-
able to algae (organic to inorganic phase and return).
Oligotrophic: "Poorly nourished," from the Greek. Describes a lake of low plant
productivity and high transparency.
Ordinary high water mark: Physical demarcation line, indicating the highest
point that water level reaches and maintains for some time. Line is visible on
rocks, or shoreline, and by the location of certain types of vegetation.
Organic matter: Molecules manufactured by plants and animals and containing
linked carbon atoms and elements such as hydrogen, oxygen, nitrogen, sul-
fur, and phosphorus.
Ooze: Lake bottom accumulation of inorganic sediments and the partially-
decomposed remains of algae, weeds, fish, and aquatic insects. Sometimes
called muck; see sediment.

Pelagic zone: This is the open area of a lake, from the edge of the littoral zone to
the center of the lake.
Pathogen: A microorganism capable of producing disease. They are of great
concern to human health relative to drinking water and swimming beaches.
B-4
-------
pH: A measure of the concentration of hydrogen ions of a substance, which ran-
ges from very acid (pH = 1) to very alkaline (pH = 14). pH 7 is neutral and
most lake waters range between 6 and 9. pH values less than 6 are con-
sidered acidic and most life forms can not survive at pH of 4.0 or lower.

Photic zone: The lighted region of a lake where photosynthesis takes place. Ex-
tends down to a depth where plant growth and respiration are balanced by
the amount of light available.

Phytoplankton: Microscopic algae and microbes that float freely in open water
of lakes and oceans.

Plankton: Planktonic algae float freely in the open water. Filamentous algae
form long threads and are often seen as mats on the surface in shallow areas
of the lake.

Primary productivity: The rate at which algae and macrophytes fix or convert
light, water, and carbon dioxide to sugar in plant cells. Commonly measured
as milligrams of carbon per square meter per hour.

Producers: Green plants that manufacture their own food through photosyn-
thesis.

Profundal zone: Mass of lake water and sediment occurring on the lake bottom
below the depth of light penetration.

Residence time: Commonly called the hydraulic residence time-the amount of
time required to completely replace the lake's current volume of water with
an equal volume of "new" water.

Respiration: Process by which organic matter is oxidized by organisms, includ-
ing plants, animals, and bacteria. The process releases energy, carbon
dioxide, and water.

Secchi depth: A measure of transparency of water obtained by lowering a black
and white, or all white, disk (Secchi disk, 20 cm in diameter) into water until it
is no longer visible. Measured in units of meters or feet.

Seepage lakes: Lakes having either an inlet or outlet (but not both), and
generally obtaining their water from groundwater and rain or snow.

Sediment: Bottom material in a lake that has been deposited after the formation
of a lake basin. It originates from remains of aquatic organisms, chemical
precipitation of dissolved minerals, and erosion of surrounding lands (see
ooze).

Soil retention capacity: The ability of a given soil type to adsorb substances
such as phosphorus, thus retarding their movement to the water.
Stratification: Layering of water caused by differences in water density. Thermal
stratification is typical of most deep lakes during summer. Chemical
stratification can also occur.

Swimmers itch: A rash caused by the skin penetration of the immature stage
(cercaria) of a flatworm (not easily controlled due to complex life cycle). A
shower or alcohol rubdown should minimize penetration.

Thermal stratification: Lake stratification caused by temperature-created dif-
ferences in water density.

Thermocline: A horizontal plane across a lake at the depth of the most rapid
vertical change in temperature and density in a stratified lake. See metalim-
nion.
B-5
-------
Topographic map: A map showing the elevation of the landscape at contours
of 2, 5,10, or 20 feet. Can be used to delineate the watershed.
Trophic state: The degree of eutrophication of a lake. Transparency,
chlorophyll-a levels, phosphorus concentrations, amount of macrophytes,
and quantity of dissolved oxygen in the hypolimnion can be used to assess
state.
Voluntary lake property owners association: Organization of property owners
in an area around a lake that members join at their option.
Water table: The upper surface of ground water; below this point, the soil is
saturated with water.
Water column: Water in the lake between the interface with the atmosphere at
the surface and the interface with the sediment layer at the bottom. Idea
derives from vertical series of measurements (oxygen, temperature, phos-
phorus) used to characterize lakewater.
Watershed: A drainage area or basin in which all land and water areas drain or
flow toward a central collector such as a stream, river, or lake at a lower
elevation.
Zooplankton: Microscopic animals which float freely in lake water, graze on
detritus particles, bacteria, and algae, and may be consumed by fish.
B-6
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Appendix C
APPENDIX C

POINT SOURCE TECHNIQUES
Septic Tank: A septic tank followed by a soil absorption bed is the traditional on-site
system for the treatment and disposal of domestic wastewater from individual households
or establishments. The system consists of a buried tank where wastewater is collected
and scum, grease, and settleable solids are removed by gravity and a sub-surface
drainage system where waste water percolates into the soil.
CRITERIA
REMARKS
1. Status

2. Applications

3. Reliability

4. Limitations

5. Cleaning
6. Treatment Side Effects
Most widely used method of on-lot domestic waste dis-
posal. Almost one-third of the U.S. population.

Used primarily in rural and suburban areas. Properly
designed and installed systems require a minimum of
maintenance and can operate in all climates.
Properly designed, constructed, and operated septic
tank systems are efficient and economical. System life
may equal or exceed 20 years.

Dependent on soil and site conditions, the ability of the
soil to absorb liquid, depth to groundwater, nature of
and depth to bedrock, seasonal flooding, and distance
to well or surface water. The sludge and scum layers in
tank must be removed every 3 to 5 years.

Groundwater contamination when pollutants are not
effectively removed by the soil. Increasing nitrate in
ground water. Soil clogging may result in surface
ponding with potential health problems.
C-1
-------
APPENDIX C
Septic Tank Mound Systems: A septic tank and mound system is a method of on-site
treatment and disposal of domestic wastewater than can be used as an alternative to
the conventional septic tank-soil absorption system. In areas where problem soil condi-
tions preclude the use of subsurface trenches or seepage beds, mounds can be installed
to raise the absorption field above ground, provide treatment, and distribute the waste-
water to the underlying soil over a wide area in a uniform manner.
CRITERIA
REMARKS
1. Status
2. Applications
3. Reliability
4. Limitations
5. Cleaning

6. Treatment Side Effects
Proven successful alternatives for difficult soil
conditions.

Alternative to septic tank-soil absorption system in
problem soil conditions. Increases amount of soil for
purification before effluent reaches groundwater.

Septic tank-mound systems are viable alternatives to
centralized treatment facilities. Dosing equipment
should be routinely maintained, and septic tanks must
be periodically pumped out for systems to operate
effectively.

Requires more space and periodic maintenance than
conventional subsurface disposal system, along with
higher construction costs. Cannot be installed on
steep slopes.

Septage requires disposal every 3 to 5 years.

Visual impact particularly in suburban areas. Drain-
age patterns and land use flexibility may also be
affected.
C-2
-------
APPENDIX C
Septic Tank-Sand Filter: Surface discharge of septic tank effluent is a method of on-site
disposal of domestic wastewater that can be used as an alternative to the conventional
soil absorption system. Where permitted by code, surface discharge units can be
employed in areas where subsurface disposal systems are not feasible. Sand filter
trenches are similar to absorption trenches, but contain an intermediate layer of sand
as filtering material and underdrains for carrying off the filtered sewage. Buried sand
filters, which required less area than trenches, also can be used.
CRITERIA
REMARKS
1. Status
2. Applications
3. Reliability

4. Limitations

5. Cleaning
6. Treatment Side Effects
Sand filtration has traditionally been employed to treat
septic tank effluent and has had success.

Surface discharge systems are alternative designs to
be used where site conditions, including geology,
hydrology, and lot size, preclude the use of the soil as
a treatment and disposal medium. Centralized man-
agement, rather than homeowners, are normally
required for successful operation.
Sand filters perform well, unless overloaded. Periodic
inspection is required to obtain proper functioning of
chlorination units.

These systems are more expensive than conventiona
on-site systems. Filter surfaces and disinfection
equipment require periodic maintenance. Buried sand
beds are inaccessible. Power is required for pumping
and some disinfection units. State or Federal dis-
charge permits along with sampling and monitoring
are required.

Sand with organic waste must be removed from inter-
mittent and recirculatmg filter surfaces when clogging
occurs and may be buried on-site or require off-site
disposal.

Treated effluents are discharged to surface waters.
Odors may emanate from open filters, and potential
C-3
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APPENDIX C
Faculative Lagoons: Faculative lagoons are intermediate depth (3 to 8 feet) ponds in
which the wastewater is stratified into three zones. These zones consist of an anaerobic
bottom layer, an aerobic surface layer, and an intermediate zone. Oxygen in the surface
stabilization zone is provided by reaeration and photosynthesis. In general, the aerobic
surface layer serves to reduce odors while providing treatment of soluble organic
by-products of the anaerobic processes operating at the bottom.
CRITERIA
REMARKS
1. Status

2. Applications

3. Reliability

4. Limitations

5. Cleaning

6. Treatment Side Effects
Fully demonstrated and in moderate use especially foi
treatment of relatively weak municipal wastewater in
areas where real estate costs are not a restricting factor.

Used for treating raw, screened, or primary settled
domestic wastewaters. Most applicable when land
costs are low and operation and maintenance costs
are to be minimized.

The service life is estimated to be 50 years. Little oper-
ator expertise is required. Overall, the system is highly
reliable.

In very cold climates, faculative lagoons may exper-
ience reduced biological activity and treatment effic-
iency. Ice formation can also hamper operations. In
overloading situations, odors can be a problem.

Settled solids may required clean out and removal
once every 10 to 20 years.

Potential seepage of wastewater into ground water
unless lagoon is lined.
C-4
-------
APPENDIX C
Oxidation Ditch: An oxidation ditch is an activated sludge biological treatment process.
Typical oxidation ditch treatment systems consist of a single or closed loop channel 4
to 6 ft. deep, with 45° sloping sidewalls. Some form of preliminary treatment such as
screening, communication or grit removal normally precedes the process. After pretreat-
ment, the wastewater is aerated in the ditch using mechanical aerators which are
mounted across the channel. The aerators provide mixing and circulation in the ditch,
as well as sufficient oxygen transfer. A high degree of nitrification may occur in the
process without special modification because of the long detention times and high solid
retention times (10 to 50 d). Secondary settling of the aeration ditch effluent is provided
in a separate clarifier. Ditch loops may be oval or circular in shape. "EH" and "horseshoe"
configurations have been constructed to maximize land usage.
CRITERIA
REMARKS
1. Status
2. Applications

3. Reliability

4. Limitations

5. Cleaning

6. Treatment Side Effects
There are nearly 650 shallow oxidation ditch installa-
tions in the U.S. and Canada. Numerous shallow and
deep oxidation ditch systems are in operation in Eur-
ope. The overall process is fully demonstrated for car-
bon removal, as a secondary treatment process.

Applicable in any situation where activated sludge
treatment is appropriate. The process cost of treatment
is generally less than other biological processes in the
range of wastewater flows between 0.1 and 10 Mgal/d.

The average reliability is good with adequate removal
of oxygen-demanding material and solids.

Oxidation ditches are relatively expensive and require
skilled operators for good performance.

Requires weekly to monthly sludge removal.

Solid waste, odor, and air pollution impacts are similar
to those encountered with standard activate sludge
processes.
C-5
-------
APPENDIX C
Trickling Filter: The process consists of a fixed bed of rock media over which wastewater
is applied for aerobic biological treatment. Slimes form on the rocks and treat the
wastewater. The bed is dosed by a distributor system, and the treated wastewater is
collected by an underdrain system. Primary treatment is normally required to optimize
trickling filter performance. The low rate trickling filter media bed generally is circular in
plan, with a depth of 5 to 10 feet.
CRITERIA
REMARKS
1. Status

2. Applications

3. Reliability

4. Limitations

5. Cleaning

6. Treatment Side Effects
This process is highly dependable in moderate climates.

Treatment of domestic and compatible industrial
wastewaters amendable to aerobic biological treat-
ment in conjunction with suitable pretreatment.

Highly reliable under conditions of moderate climate.
Mechanical reliability high. Process operation
requires little skill.

Vulnerable to climate changes and low temperatures,
filter flies and odors are common, periods of inade-
quate moisture for slimes can be common. High land
and capital cost requirements.

Sludge is withdrawn from the secondary clarifier at a
rate of 3,000 to 4,000 gal/Mgal of wastewater, contain
ing 500 to 700 Ib dry solids.

Odor problems; high land requirement relative to
many alternative processes; and filter flies.
C-6
-------
APPENDIX C
Overland Flow Treatment: Wastewater is applied by gravity flow to vegetated soils that
are slow to moderate in permeability and is treated as it travels through the soil matrix
by filtration, adsorption, ion exchange, precipitation, microbial action and also by plant
uptake. An underdrainage system consisting of a network of drainage pipe buried below
the surface serves to recover the effluent, to control groundwater, or to minimize trespass
of wastewater onto adjoining property by horizontal subsurface flow. Vegetation is a vital
part of the process and serves to extract nutrients, reduce erosion and maintain soil
permeability.
CRITERIA
REMARKS
1. Status

2. Applications
3. Reliability

4. Limitations
5. Cleaning

6. Treatment Side Effects
Has been widely and successfully utilized for more
than 100 years.

Can provide the following benefits: 1) an economic
return from the reuse of water and nutrients to produce
marketable crops or forage; 2) water conservation
when utilized for irrigating landscaped areas; 3) a
means of recovering renovated water for reuse or for
discharge; 4) a means of controlling groundwater.

Extremely reliable.

Process is limited by soil type and depth, topography,
underlying geology, climate, suface and groundwater
hydrology and quality, crop selection and land avail-
ability. Graded land is essential; excessive slope
increase runoff and erosion. Climate affects growing
season and application ceases during periods of fro-
zen soil conditions. Prolonged wet spells limit appli-
cation by Gulf states and the Pacific Northwest
coastal region.
Minimal, when properly operated.
C-7
-------
Appendix D
Much of the material in this appendix was taken from EPA's Guide to
Nonpoint Source Pollution Control, published by the Office of Water in
1987.
APPENDIX D

BEST MANAGEMENT PRACTICES
Conservation Tillage: A farming practice that leaves stalks or stems and roots intact
in the field after harvest. Its purpose is to reduce water runoff and soil erosion compared
to conventional tillage where the topsoil is mixed and turned over by a plow. Conservation
tillage is an umbrella term that includes any farming practice that reduces the number
of times the topsoil is mixed. Other terms that are used instead of conservation tillage
are (1) minimum tillage where one or more operations that mixed the topsoil are elimi-
nated; and (2) no-till where the topsoil is left essentially undisturbed.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)

d) Runoff

2. Capital Costs
3. Operation and
Maintenance
4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
Fair to excellent, decreases sediment input to streams
and lakes. (40 to 90 percent reduced tillage, 50 to 95
percent no tillage).
Poor, no effect on nitrogen input to streams and lakes.
Fair to excellent, can reduce the amount of phos-
phorus input to streams and lakes. (40 to 90 percent
reduced tillage, 50 to 95 percent no tillage).
Fair to excellent, decreases amount of water running
off fields carrying sediment and phosphorus.

High, because requires purchase of new equipment
by farmer.

Less expensive than conventional tillage. Potential
inrease in herbicide costs. Potential increase in net
farm income.

Good, approximately every five years the soil has to
be turned over.

Fair to excellent.

Good, but may be limited in northern areas that exper-
ience late cool springs, or in heavy, poorly drained soils.
Potential increase in herbicide effects and insecticide
contamination of surface and groundwater. Nitrogen
contamination of groundwater.
Consider fertilizer management and integrated
pesticide management.
D-1
-------
Best management practices (cont.)
Integrated Pest Management: Pests are any organisms that are harmful to desired
plants, and they are controlled with chemical agents called pesticides. Integrated pest
management considers factors such as how much pesticide is enough to control a
problem, the best method of applying the pesticides, the appropriate time for application
and the safe handling, storage and disposal of pesticides and their containers. Other
considerations include using resistant crop varieties, optimizing crop planting time,
optimizing time of day of application, rotating crops and biological controls.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
No effect, but pesticides attached to soil particles can
be carried to streams and lakes.
No effect.
No effect.
No effect, but water is the primary route for transport-
ing pesticides to lakes and streams.

No effect.

Farming cost, potential reduction in pesticide costs
and an increase in net farm income.

Poor, as pesticides are applied one or more times per
year to address different pests and different crops.

Fair to excellent, reported pollutant reductions range
from 20-90 percent.

Methods are generally applicable wherever pesticides
are used: forest, farms, homes.

Potential for ground and surface water contamination.
Toxic components may be available to aquatic plants
and animals.

See crop rotation, conservation tillage.
D-2
-------
Best management practices (cont.)
?£^HC'«an'"9-: Streets and parking lots can be cleaned by sweeping which removes
large dust and dirt particles or by flushing which removes finer particles. Sweeping
actually removes solids so pollutants do not reach receiving waters. Flushing just moves
1,1"°^ ^ draina9e svstem unless the drainage system is part of the sewer
system. When the drainage system is part of the sewer system, the pollutants will be
treated as wastes in the sewer treatment plant.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Poor, not proven to be effective.
Poor, not proven to be effective.
Poor, not proven to be effective.
No effect.

High, because it requires the purchase of equipment
by community.

Unknown but reasonable vehicular maintenance
would be expected.

Poor, have to sweep frequently throughout the year.

Poor.

To paved roads, might not be considered a worthwhile
expenditure of funds in communities less than 10,000.

Unknown.
Detention/Sedimentation basins.
D-3
-------
Best management practices (cont.)
Streamside Management Zones (Buffer strips): Considerations in streamside man-
agement include maintaining the natural vegetation along a stream, limiting livestock
access to the stream, and where vegetation has been removed planting buffer strips.
Buffer strips are strips of plants (grass, trees, shrubs) between a stream and an area
being disturbed by man's activities that protects the stream from erosion and nutrient
impacts.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)

c) Phosphorus (P)

d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
Good to excellent, reported to reduce sediment from
feedlots on 4 percent slope by 79 percent.
Good to excellent, reported to reduce nitrogen from
feedlots on 4 percent slope by 84 percent.
Good to excellent, reported to reduce phosphorus
from feedlots on 4 percent slope by 67 percent.
Good to excellent, reported to reduce runoff from feed-
lots on 4 percent slope by 67 percent.

Good, moderate costs for fencing material to keep out
livestock and for seeds or plants.

Excellent, minimal upkeep.
Excellent, maintain itself indefinitely.

Fair, because of the lack of intensive scientific research.

May be used anywhere. Limitations on types of plants
that may be used between geographic areas.

With trees, shading may increase the diversity and
number of organisms, in the stream with the possible
reduction in algae.

Conservation tillage, animal waste management, live-
stock exclusion, fertilizer management, pesticide
management, ground cover maintenance, proper
construction, use, maintenance of haul roads and
skid trails.
D-4
-------
Best management practices (cont.)
Contour Farming: A practice where the farmer plows across the slope of the land. This
practice is applicable on farm land with a 2-8 percent slope.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good on moderate slopes (2 to 8 percent slopes), fair
on steep slopes (50 percent reduction).
Unknown.
Fair.
Fair to good, depends on storm intensity.

No special effect.

Poor, it must be practiced every time the field is plowed.

Poor, not enough information.

Good, limited by soil, climate, and slope of land. May
not work with large farming equipment on steep slopes.

Side effects not identified.
Fertilizer management, integrated pesticide manage-
ment, possibly streamside management.
Contour Stripcropping: This practice is similar to contour farming where the farmer
plows across the slope of the land. The difference is that strips of close growing crops
or meadow grasses are planted between strips of row crops like corn or soybeans.
Whereas contour farming can be used on 2-8 percent slopes, contour Stripcropping can
be used on 8-15 percent slopes.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability
7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good, 8 to 15 percent slopes, provides the benefits of
contour plowing plus buffer strips.
Unknown, assumed to be fair to good.
Unknown, assumed to be fair to good.
Good to excellent.

No special effect unless farmer cannot use the
two crops.

No special effect.
Poor, must be practiced year after year.

Poor, not enough information.

Fair to good, may not work with large farming equip-
ment on steep slopes.

Side effects not identified.
Fertilizer management, integrated pesticide
management.
D-5
-------
Best management practices (cont.)
Range and Pasture Management: The objective of range and pasture management is
to prevent overgrazing because of too many animals in a given area. Management
practices include spreading water supplies, rotating animals between pastures, spreading
mineral and feed supplements or allowing animals to graze only when a particular plant
food is growing rapidly.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs

3. Operation and
Maintenance

4. Longevity

5. Confidence
6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good, prevents soil compaction which reduces infiltra-
tion rates.
Unknown.
Unknown.
Good, maintains some cover which reduces runoff
rates.

Low, but may have to develop additional water sources.

Low.

Excellent.

Good to excellent. Farmer must have a knowledge of
stocking rates, vegetation types, and vegetative
conditions.

Excellent.

None identified.
Livestock exclusion, riparian zone management and
crop rotation.
D-6
-------
Best management practices (cont.)
Crop Rotation: Where a planned sequence of crops are planted in the same area of
land. For example, plow based crops are followed by pasture crops such as qrass or
legumes in two to four year rotations.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs
3. Operation and
Maintenance
4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good when field is in grasses or legumes
Fair to good.
Fair to good.
Good when field is in grasses or legumes.

High if farm economy reduced. Less of a problem with
livestock which can use plants as food.

Moderate, increased labor requirements. May be off-
set by lower nitrogen additions to the soil when corn is
planted after legumes, and reduction in pesticide
application.

Good.

Fair to good.

Good, but some climatic restrictions.

Reduction in possibility of groundwater contamination.

Range and pasture management.
Terraces: Terraces are used where contouring, contour strip cropping, or conservation
tillage do not offer sufficient soil protection. Used in long slopes and slopes up to 12
percent; terraces are small dams or a combination of small dams and ditches that reduce
the slope by breaking it into lesser or near horizontal slopes.
CRITERIA
REMARKS
1. Effectiveness
a. Sediment
b. Nitrogen (N)
c. Phosphorus (P)
d. Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effect

8. Concurrent Land
Management Practices
Fair to good.
Unknown.
Unknown.
Fair, more effective in reducing erosion than total run-
off volume.

High initial costs.

Periodic maintenance cost, but generally offset by
increased income.

Good with proper maintenance.

Good to excellent.

Fair, limited to long slopes and slopes up to 12 percent.

If improperly designed or used with poor cultural and
management practices, they may increase soil erosion.

Fertilizer and pesticide management.
D-7
-------
Best management practices (cont.)
Animal Waste Management: A practice where animal wastes are temporarily held in
waste storage structures until they can be utilized or safely disposed. Storage units can
be constructed of reinforced concrete or coated steel. Wastes are also stored in earthen
ponds.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff
2. Capital Costs

3. Operation and
Maintenance
4. Longevity
5. Confidence
6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
Not applicable.
Good to excellent.
Good to excellent.
Not applicable.
High because of the necessity of construction and
disposal equipment.
Unknown.
Unknown.
Fair to excellent if properly managed.
Good.
The use of earthen ponds can possibly lead to ground
water contamination.
Fertilizer management.
Nonvegetative Soil Stabilization: Examples of temporary soil stabilizers include
mulches, nettings, chemical binders, crushed stone, and blankets or mats from textile
material. Permanent soil stabilizers include coarse rock, concrete, and asphalt. The
purpose of soil stabilizers is to reduce erosion from construction sites.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoffs
2. Capital Costs
3. Operation and
Maintenance
4. Longevity
5. Confidence
6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
Excellent.
Poor.
Poor.
Poor on steep slopes with straw mulch, otherwise good.
Low to high, depending on technique applied.
Moderate.

Generally a temporary solution until a more perma-
nent cover is developed. Excellent for permanent soil
stabilizer.
Good.
Excellent.
No effect on soluble pollutants.

Runoff detention/retention.
D-8
-------
Best management practices (cont.)
Porous Pavement: Porous pavement is asphalt without fine filling particles on a gravel
CRITERIA
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff
2. Capital Costs

3. Operation and
Maintenance

4. Longevity
5. Confidence
6. Adaptability
7. Potential Treatments
Side Effects
8. Concurrent Land
Management Practices
REMARKS

Good.
Good.
Good.
Good to excellent.
Moderate, slightly more expensive than conventional
surfaces.
Potentially expensive, requires regular street main-
tenance program and can be destroyed in freezing
climates.
Good, with regular maintenance (i.e., street cleaning),
in southern climates. In cold climates, freezing and
expansion can destroy.
Unknown.
Excellent.
Groundwater contamination from infiltration of soluble
pollutants.
Runoff detention/retention.

Flood Storage (Runoff Detention/Retention): Detention facilities treat or filter out
pollutants or hold water until treated. Retention facilities provide no treatment. Examples
of detention/retention facilities include ponds, surface basins, underground tunnels,
excess sewer storage and underwater flexible or collapsible holding tanks.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Costs
3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Use Practices
Poor to excellent, design dependent.
Very poor to excellent, design dependent.
Very poor to excellent, design dependent.
Poor to excellent, design dependent.

Dependent on type and size. Range from $100 to
$1,000, per acre served, depending on site. These
costs include capital costs and operational costs.

Annual cost per acre of urban area served has ranged
from $10 to $125 depending on site.

Good to excellent, should last several years.

Good, if properly designed.

Excellent.

Groundwater contamination with retention basins.
Porous pavements.
D-9
-------
Best Management Practices (Cont.)
Sediment Traps: Sediment traps are temporary structures made of sandbags, straw
bales, or stone. Their purpose is to detain runoff for short periods of time so heavy
sediment particles will drop out. Typically, they are applied within and at the periphery
of disturbed areas.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good, coarse particles.
Poor.
Poor.
Fair

Low

Low, require occasional inspection and prompt
maintenance.

Poor to good.

Poor.

Excellent.

None identified.
Agricultural, silviculture or other construction best
management practices could be incorporated
depending on situation.
Surface Roughening: On construction sites, the surface of the exposed soil can be
roughened with conventional construction equipment to decrease water runoff and slow
the downhill movement of water. Grooves are cut along the contour of a slope to spread
runoff horizontally and increase the water infiltration rate.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good.
Unknown.
Unknown.
Good.

Low, but requires timing and coordination.

Low, temporary protective measure.

Short-term.

Unknown.

Excellent.

None identified.

Nonvegetative soil stabilization.
D-10
-------
Best Management Practices (Cent.)
Riprap: A layer or loose rock or aggregate placed over a soil surface susceptible to
erosion.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good, based on visual observations.
Unknown.
Unknown.
Poor.

Low to high, varies greatly.

Low.

Good, with proper rock size.

Poor to good.

Excellent.

In streams, erosion may start in a new,
unprotected place.

Streamside (lake) management zone.
Interception or Diversion Practices: Designed to protect bottom land from hillside
runoff, divert water from area! sources of pollution such as barnyards or to protect
structures from runoff. Diversion structures are represented by any modification of the
surface that intercepts or diverts runoff so that the distance of flow to a channel system
is increased.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Fair to good (30 to 60 percent reduction).
Fairto good (30 to 60 percent reduction).
Fair to good (30 to 60 percent reduction).
Poor, not designed to reduce runoff but divert runoff.

Moderate to high, may entail engineering design and
structures.

Fair to good.
Good.

Poortogood, largely unknown.

Excellent.

None identified.
Since the technique can be applied under multiple
situations (i.e., agriculture, silviculture, construction)
appropriate best management practices associated
with individual situations should be applied.
D-11
-------
Best Management Practices (Cont.)
Grassed Waterways: A practice where broad and shallow drainage channels (natural
or constructed) are planted with erosion-resistant grasses.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost

3. Operation and
Maintenance

4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good to excellent (60 to 80 percent reduction).
Unknown.
Unknown.
Moderate to good.

Moderate.

Low, but may interfere with the use of large equipment.

Excellent.

Good.

Excellent.

None identified.
Conservative tillage, integrated pest management,
fertilizer management, animal waste management.
D-12
-------
Best management practices (Cont.)
Maintain Natural Waterways: This practice disposes of tree tops and slash in areas
away from waterways. Prevents the buildup of damming debris. Stream crossings are
constructed to minimize impacts on flow characteristics.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment
b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff
2. Capital Cost

3. Operation and
Maintenance
4. Longevity
5. Confidence
6. Adaptability
7. Potential Treatment
Side Effects
8. Concurrent Land
Management Practices
Fair to good, prevents acceleration of bank and
channel erosion.
Unknown, contribution would be from decaying debris.
Unknown, contribution would be from decaying debris.
Fair to good, prevents deflections or constrictions of
stream water flow which may accelerate bank and
channel erosion.
Low, supervision required to ensure proper disposal
of debris.
Low, if proper supervision during logging is main-
tained, etherise $160-$800 per 100 ft stream.
Good.
Good.
Excellent.
None identified.
Proper design and location of haul and skid trails;
Streamside management zones.
D-13
-------
Best management practices (Cent.)
Haul Roads and Skid Trails: This practice is implemented prior to logging operations.
It involves the appropriate site selection and design of haul road and skid trails. Haul
roads and skid trails should be located away from streams and lakes. Recommended
guidelines for gradient, drainage, soil stabilization, and filter strips should be followed.
Routes should be situated across slopes rather than up or down slopes. If the natural
drainage is disrupted, then artificial drainage should be provided. Logging operations
should be restricted during adverse weather periods. Other goods practices include
ground covers (rock or grass) closing roads when not in use, closing roadways during
wet periods, and returning main haul roads to prelogging conditions when logging ceases.
CRITERIA
REMARKS
1. Effectiveness
a) Sediment

b) Nitrogen (N)
c) Phosphorus (P)
d) Runoff

2. Capital Cost
3. Operation and
Maintenance
4. Longevity

5. Confidence

6. Adaptability

7. Potential Treatment
Side Effects

8. Concurrent Land
Management Practices
Good if grass cover is used on haul roads (45 percent
reduction); Excellent if crushed rock is used as ground
cover (92 percent reduction).
Unknown.
Unknown.
Unknown.

High, grass cover plus fertilizer $5.37/100 ft roadbed,
crushed rock (6 in) $179.01 /100 ft roadbed.

High, particularly with grass which may have to be
replenished routinely and may not be effective on
highly traveled roads.

Unknown.

Good for ground cover, poor for nutrients.

Good.

Potential increase in nutrients to water course if
excess fertilizers are applied.

Maintain natural waterways.
D-14
-------
Appendix E
INTRODUCTION
In preparation for the State/Provincial Lake Management Programs workshop
held at the Sixth Annual NALMS Symposium in Portland, Oregon, lake manage-
ment program managers from each State and Province were asked to provide
information on their programs. The information received from States and Pro-
vinces is summarized in the following pages. This document is only intended as
a preliminary compilation of State/Provincial lake management program infor-
mation. Thus, in some cases the agency that supplied information for this listing
may not have been the only agency in the State/Province dealing with lake
management issues.
For further details about the information summarized herein please contact
Richard S. McVoy (617/366-9181), DEQE, Div. of Water Pollution Control, Lyman
School, Westview Building, Westborough, MA 01581.
E-1
-------
ARIZONA
Purpose

Emphasis
Program
Elements
Funding
Source(s)

Staff

Interactions
Arizona Game & Fish Department
P.O. Box 9099
Phoenix, Arizona 85068-9099

Protection and management of sport and non-game fisheries
and aquatic resources (streams and reservoirs).

Focus on long range management and short term emergency
response (pollution spills and fishkills).

1. Extensive limnological surveys which include analysis of
water, sediment, and tissue samples to determine any chan-
ges in the aquatic resources due to pollution.
2. Fisheries surveys to identify species composition, relative
abundance, age, growth condition and length frequencies.
3. Creel surveys to determine species harvest, catch rates,
fishermen opinion, preference, and fish distribution among
anglers.
4. Periodic angler questionnaire to understand the needs and
wants of the angler.
5. Habitat alterations (artificial reefs, stream deflectors, fencing,
revegetation, bank stabilization, and aquatic weed removal)
to attract fish and to improve habitat and water quality.
6. Establish fishing regulations to fish resource.
7. Employ outboard motor restrictions.

Federal and State hunting and fishing money.

18 (aquatic resource background).

Public: Trout Unlimited, Anglers United, Bass Clubs.
Private: Not listed.
Governmental: Federal- Army Corps, Forest Service, Land
Management, Reclamation, National Park Service
State: Dept. Health Services, State Parks, Salt River Project
Academic: U. Arizona, Arizona State U., Northern Arizona U.
Program
Elements
Arizona Department of Health Services
Division of Environmental Health
Central Palm Plaza Building
2005 North Central Avenue
Phoenix, Arizona 85004

1. Discharge limitations for point discharges to surface waters.
2. Promulgation of surface water quality standards.
3. Developing a non-point source control program.
E-2
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ARKANSAS
Purpose
Arkansas Game and Fish Commission
2 Natural Resources Drive
Little Rock, AR 72205

Fisheries management of existing lake ecology.
Purpose
Emphasis
Program
Elements
CONNECTICUT
Department of Environmental Protection
Water Compliance Unit
Lakes Management Section
165 Capitol Avenue
Hartford, Connecticut 06106

To develop and implement water quality management
strategies and policies which will deal with the problem of lake
eutrophication, particularly excessive algae and aquatic plant
growth.

The program focuses on management of both Statewide con-
cerns (nonpoint source management policy and construction
grants program) and individual lake projects. Grants are used
as a key aspect of management.

1. Trophic status assessment: A study completed in the late
1970's was the basis for establishing program priorities.
2. Municipal/industrial discharge management: Evaluation of
lake water quality benefits attained after the implementation
of advanced wastewater treatment through State construc-
tion grants.
3. Water quality standards: No discharges to Class A lakes. Dis-
charges to certain Class B lakes can't raise phosphorus
levels above 0.003 mg/l. A lake trophic classification system
is included.
4. Nonpoint source control: Development and distribution of a
guide to best management practices for controlling nonpoint
sources in lake watersheds.
5. Federal Clean Lakes Program: Administration of grants from
Section 314 Program for Phase I studies and Phase II im-
plementation projects.
6. Algae and weed control program: Administration of a reim-
bursement program to provide State funds to communities
for algae and weed control. $30-60,000/yr.
7. Special projects: State appropriations have been made for
projects to a) purchase a hydraulic dredge for lake manage-
ment projects and b) develop individual lake management
projects.
E-3
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Assistance/
Service
Funding
Sources
Staff
Interactions
Other Lake-
Related
Programs
Handbooks on best management practices for nonpoint source
controls, algae and weed control methods, and nuisance
aquatic vegetation control; reimbursement funds for aquatic
weed/algae control; and technical assistance to towns, lake as-
sociations, and private pond owners.

Individual lake projects funded through Federal 314 grants and
State legislative appropriations. Staff is Federally funded
through water quality program grants.

Three environmental analysts contribute part time to the
program.

Public: Provide information to public.
Governmental: Grants/reimbursements to municipalities.

DEP, Pesticides Section, Hazardous Materials Management
Unit;'DEP, Fisheries Bureau; DEP, Water Resources Unit
E-4
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DELAWARE
Department of Natural Resources & Environmental Control
Division of Fish and Wildlife
89 Kings Highway
P.O. Box1401
Dover, DE 19903

Purpose Provide maximum fishing opportunity for freshwater anglers.

Emphasis Applied research and management dealing primarily with in-
dividual problem lakes. Some problems (e.g., Hydrilla) deal
with multiple water bodies.

Program 1. Fisheries management through (a) evaluation of fish intro-
Elements ductions, (b) investigation of largemouth bass regulation
changes, (c) impact of advanced fingerling stocking, (d) res-
toration of herring runs into freshwater impoundments, and
(e) evaluation of freshwater fishing by mail creel survey.
2. Investigation of vegetation removal in ponds by (a) evaluation
of partial aquatic vegetation removal, (b) evaluation of
biological control, (c) Hydrilla investigations.
3. Evaluation of dredging on a freshwater community including
the impact of wetlands loss on a pond and sediment map-
ping of public ponds.

Assistance/ Biologist available to assist owners on all ponds (private or
Services public).

Funding Federal funds through the Dingell-Johnson Program and State
Sources funds through license receipts.

Staff 6 (primarily biology/ecology/fisheries background).

Interactions Public: Creel interviews and angler diaries.
Private: None listed.
Governmental: Technical assistance to State/county parks and
recreation departments and soil conservation services.

Other Lake- Soil Conservation Service: Technical aid to private owners;
Related University of Delaware Extension Service; Delaware State Col-
Programs lege Cooperative Fisheries Unit
E-5
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FLORIDA
Emphasis
Program
Elements
Assistance/
Services
Funding
Sources

Staff
Florida Game and Fresh Water Fish Commission
207 West Carroll Street
Kissimmee, FL 32741

Primarily management oriented; dealing with problem lakes or
watersheds. Discharge of sewage is the only Statewide
problem. Normally grants are not pursued but assistance is
provided for local governments to apply.

1. Development of lake restoration plans based on needs of
aquatic habitat, fisheries, and wildlife and considering such
factors as water quality and quantity, elevation manipulation
and aquatic plant management.
2. Point and non-point source considerations.
3. Many plans have been developed using drawdown or
pumpdown to restore aquatic habitat and associated fish
and wildlife values.
4. Cooperation with Federal, State, and local agencies and
elected officials to implement planned programs.

Develop or assist in development of restoration plans for public
lakes of greater than 5 acres. Also provide services by recom-
mending management techniques to enhance fish and wildlife
values.

Entirely from sale of fishing licenses.
5 fisheries biologists; 2 technicians; 1 secretary (strong back-
grounds in lake drawdown, pollution control methodologies,
and surface water hydrology).
Interactions
Public: Considerable from phone calls to formal public hear-
ings.
Private: Work with consultants during project planning and im-
plementation.
Governmental: Many other agencies during the planning and
implementation of projects.
E-6
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Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff

Interactions
IDAHO

Department of Health and Welfare
Division of Environment
State House
Boise, Idaho 83720-990

Responsible for protecting all surface and underground waters.
Although there is no specific lake management program, efforts
are underway to formally create one.

Focuses on individual lake problems (trophic status assess-
ments, source evaluations, and problem-solving alternatives)
and broader range problems (State water quality standards and
nonpoint source control strategies). Grant administration is also
a function of the Division.

Lake protection efforts are primarily a "grass roots" movement
which the State tries to augment in the following ways.
1. Networking by (a) maintaining contacts and exchanging in-
formation with lake associations, NALMS, resource agencies
and universities; (b) facilitating the formation of new lake as-
sociations; and (c) organizing and participating in lake
management task forces.
2. Provide information and education by (a) holding public
workshops on lake management topics and (b) developing
and providing informational materials on lake protection.
3. Provide technical support by (a) conducting water quality
studies to evaluate lake conditions and sources of problems,
(b) participating in cooperative studies with lake associa-
tions or other agencies, (c) providing technical advice to lake
associations on special projects, (d) providing laboratory
support for other water quality studies, and (e) providing
guidance and training for voluntary monitoring activities.
4. Providing funding for (a) construction of municipal sewage
treatment facilities and (b) implementation of agricultural
best management practices.

See Program elements above.
Positions are Federally funded. Treatment facility and agricul-
tural BMP grants are Federal and State funded.

2 half-time limnologists.

Public: Extensive contact with local lake associations.
Private: Not listed.
Governmental: Not listed.
E-7
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ILLINOIS
Purpose

Emphasis
Program
Elements
Assistance/
Services
Funding
Sources

Staff
Interactions
Illinois Environmental Protection Agency
Division of Water Pollution Control
Planning Section
2200 Churchill Road
Springfield, Illinois 62706

To protect, enhance, and restore the quality and usability of lake
ecosystems.

An integrated, multidisciplinary approach to lake use enhance-
ment involving watershed protection and in-lake management
to mitigate past damage.

1. Monitoring and lake classification to guide decision making.
(a) Volunteer Lake Monitoring Program (VLMP): 250 lakes
monitored for Secchi disc transparency; 12 for nutrients and
suspended solids.; (b) Ambient Lake Monitoring Program
(ALMP): about 20 lakes/year monitored by Division person-
nel.
2. Development and implementation of lake/watershed manage-
ment plans for public lakes under the Federal Clean Lakes
Program: Administration of the CLP funded protection/res-
toration projects. Currently, three projects ongoing; 2 com-
pleted.
3. Technical assistance and coordination to promote planning
and implementation initiatives funded by other sources: In-
teractions with other Federal, State, and local groups and
agencies.

Information and training for VLMP volunteers, other educational
and technology transfer information, development of
lake/watershed implementation plans.

Federally funded through Sections 314, 106, and 205(j) of the
Clean Water Acts.

3 full-time aquatic biologists (Springfield HQ) plus regional of-
fice technicians and aquatic biologists.

Public: Citizen volunteers (VLMP), Illinois Lake Management As-
sociation, Northeastern Illinois Planning Commission.
Private: Not listed.
Governmental: Federal - USEPA, USDA.
State: Dept. of Agriculture, Dept. of Conservation, State Water
Survey.
E-8
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Illinois Department of Conservation
Division of Fish & Wildlife (Impoundment Program)
Lincoln Tower Plaza
524 South Second Street
Springfield, Illinois 62701-1787

Purpose The Impoundment Program has stewardship of protecting, en-
hancing, and insuring the wise use of aquatic resources in order
to sustain quality angling for sport-fishermen.

Emphasis The program focuses on data acquisition, management plans
and techniques, and public information.

Program 1. Investigations and surveys: Monitoring of fish populations
Elements and environments to detect changes which require manage-
ment strategies to be implemented.
2. Technical assistance: Provide consultation, management
guidelines, plans, and policies to public and private im-
poundment owners to conserve the fishery resources while
providing quality sportfishing.
3. Information dissemination: Publish and distribute results of
surveys, management projects, fish population status, tech-
nical management reports, and impoundment management
plans to provide information regarding fishing opportunities
and impoundment management to lake managers and sport
fishermen.

Assistance/ Technical assistance, management plans, published informa-
Services tional materials.

Funding Not listed.
Sources

Staff One program manager, 5 regional fisheries administrators, 17
district fisheries managers.

Interactions Public: Extensive response to inquires for information.
Private: Not listed.
Governmental: Not listed.

Other Lake- Illinois Dept. of Conservation Fisheries management and State
Related park management; Illinois State Water Survey: Lake manage-
Programs ment research; Illinois Lake Management Assoc.: Non-profit or-
ganization to promote understanding and comprehensive lake
resource management.
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INDIANA
Department of Natural Resources
Division of State Parks
Room 616, State Office Building
Indianapolis, Indiana 46204-2267

Maintenance of lakes within State parks.

The primary interest includes both the broad and specific cases
of controlling siltation in lakes and ponds. A major concern is
whether silt removal and control is equal in value to the benefits
of saving the lakes.

1. Hydraulic dredging: For about 4 years this method has been
used to offset siltation.
2. Research on less expensive siltation control methods: This
program is planned to start next year pending State funding.

Hydraulic dredging.
Purpose

Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Interactions
Other Lake-
Related
Programs
Through State legislature.

4 people for dredging program (maintenance background). No
lake specialists employed.

Public: Not listed.
Private: Not listed.
Governmental: Division of Water and Division of Fish and
Wildlife provide lake management experts.

DNR, Division of Water; DNR, Division of Fish and Wildlife:
Manages lakes for fisheries.
E-10
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KANSAS
Purpose

Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Interactions
Department of Health and Environment
Bureau of Water Protection
Water Quality Assessment Section
Forbes Field
Topeka, Kansas 66620-0110

To provide water quality information on lakes and address cur-
rent concerns of the public and the Department.

Program stresses data acquisition and investigation to address
individual lake problems and to assess generic problems such
as eutrophication or nonpoint sources. Response to public con-
cerns is a key focus of the program.

1. Routine lake monitoring: 15-30 lakes/year.

2. Special investigations: Performed in-house or in cooperation
with other State, Federal, or local agencies, these studies in-
clude: (a) the formation of trihalomethanes in drinking water
supply reservoirs, (b) the occurrence and persistence of
pesticides in drinking water reservoirs, (c) the effects of non-
point source pollutants on lake water quality, and (d) the
causes and control of taste and odor problems reported by
the public or treatment plant operators.

Special investigative surveys in response to public notifications
of observed lake problems.

The lake monitoring program is funded by the Federal and State
governments.

4 staff with aquatic biology backgrounds assist (% each) in the
lake monitoring program. Also, 3-5 part-time environmental
technicians assist (20% time, total).

Public: Extensive response to public requests.
Private: Little to none.
Governmental: Grants for special studies.
Academic: Grants for special studies.
E-11
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KENTUCKY
Department of Environmental Protection
Division of Water
Fort Boone Plaza
18ReillyRoad
Frankfort, Kentucky 40601

Purpose To provide lake water quality data for making management
decisions on the use of point and nonpoint source controls to
alleviate use impairments.

Emphasis Data acquisition.
Program
Elements
Assistance/
Service

Funding
Sources

Staff

Interactions
1. Ambient monitoring program: Nine lakes are monitored for
eutrophication trends and potential acid precipitation im-
pacts.
2. Lake classification survey: The survey was completed in 1983
using Federal Clean Lakes Program funds. This information
is used to make decisions on new point source discharges in
lake watersheds.
3. Citizens participation program (Water Watch): Designed to
actively educate the public about water quality problems.
One element ("adopt a lake" program) allows local groups to
learn about their lakes and watersheds.

Staff assistance in educating volunteer groups on lake sampling
and limnology; advise on private lake management problems.

Mainly Federal (Section 205j) funds.
2 part-time employees (aquatic biologists).

Public: Local volunteer groups through the monitoring/educa-
tion program. Response to inquires on lake problems.
Private: Consulting firms, developers.
Governmental: Federal - Army Corps of Engineers, Soil Con-
servation Service.
Interstate: Tennessee Valley Authority.
State: Department of Fish and Wildlife Resources.
Local: City officials.
E-12
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LOUISIANA
Department of Environmental Quality
Office of Water Resources
Natural Resources Building
P.O. Box 44091
Baton Rouge, Louisiana 70804

Purpose Responsible for protecting and preserving the quality of all sur-
face waters in the State. Lake water quality problems are hand-
led within the framework of the whole program; there is no
separate lake program.

Emphasis This water quality management and planning program is
designed to be flexible so that a variety of activities can be used
to deal with whatever problems arise. Grant aid has been used
for both general and specific lake investigations.

Program 1. Monitoring: Establishment and implementation of monitoring
Elements networks.
2. Water quality data assessment: On a case-by-case basis for
any waterbody.
3. Wastewater discharge permits: Development, issuance, and
enforcement of permits for discharges to any water body.
4. Lake classification: An inventory of lakes and their trophic in-
dices was completed using Federal Clean Lakes Program
funds.

Technical expertise and databases available. Field staff respond
to water quality complaints and fishkills.

Combination of Federal grants and self-generated fund from
permit fees and fines.

About 100 members for all water quality issues.

Public: Attend public meetings on water quality issues.
Private: With consultants and private industry regarding the per-
mitting process.
Governmental: Regulatory agreement with Louisiana Depart-
ment of Wildlife and Fisheries.

Other Lake- Louisiana Department of Agriculture: Nonpoint sources; Soil
Related and Water Conservation Commission: Nonpoint sources;
Programs Department of Transportation: Water sources and quantity-
Department of Health: Water quality (coliforms); Department of
Wildlife and Fisheries: Fish resources; Soil and Conservation
Service: Nonpoint sources, irrigation; U.S. Geological Survey:
Flow and hydrology
Assistance/
Services

Funding
Sources

Staff

Interactions
E-13
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MAINE
Purpose
Program
Elements
Assistance/
Services

Funding
Sources

Staff

Interactions
Department of Environmental Protection
State House #17
Augusta, Maine 04333

To direct long-term planning, protect lake water quality, and in-
form and educate the public so as to maintain or improve the
present water quality of Maine's 5000 lakes and ponds.

1. Vulnerable Lake Identification: Determining which lakes need
protection or restoration using vulnerability indices, value in-
dices, lake benthic indices, volunteer monitoring programs,
critical area program, and LURC wildlands lake assessment.
2. Priority List: Included on the list are lakes (a) with declining
water quality, (b) sensitive for phosphorus loading, (c) in
critical areas, and (d) with cultural stress but stable water
quality.
3. Protection Plans: Plans are formulated taking into account
water quality data from volunteer monitoring and diagnostic
studies, land use trends, lake associations (lobby), town offi-
cials, local ordinances, soils information, subdivision
reviews, and conservation easements.
4. Best Management Practices: Encouragement in the use of
BMPs at the State level through site and subdivision review,
the Great Ponds Act, and the Wetlands Act. DEP assistance
is provided for municipalities on development review, or-
dinances and zoning, watershed districts, and town enforce-
ment roles.
5. Development of a broad base of support through general
public and school education programs.
6. Lake Restoration:Problem lakes which deviate from the
natural State are marked for efforts to control cultural ac-
tivities.
7. Nonpoint Source Reduction: Efforts are aimed at agriculture,
forestry, and transportation.
8. Other issues being studied include: conflicting policies,
cumulative impact guidelines, scenic values, open space for
lakes, conflicting uses, and aquatic plant issues.

Technical guidance to municipalities and lake associations.
State funds.

Not listed.

Not listed.
E-14
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MASSACHUSETTS
Department of Environmental Quality Engineering
Division of Water Pollution Control
Lyman School, Westview Building
Westborough, Massachusetts 01581

Purpose To restore, preserve, and maintain publicly owned lakes and
ponds for recreation and enjoyment.

Emphasis The program focuses on providing monetary and technical as-
sistance to communities for lake restoration and on water
quality data acquisition.

Program 1. State Clean Lakes Program: Administration of a matching
Elements grant aid program to provide funds for diagnostic/feasibility
studies, long-term restoration/preservation projects, and
short-term inlake maintenance projects.
2. Federal Clean Lakes Program: Administration of Federally
funded CLP implementation projects.
3. Water quality monitoring: Limnological sampling to obtain
lake water quality data a) to determine baseline lake condi-
tions, b) to monitor post-implementation project changes,
and c) to respond to public concerns about lake problems.
4. Aquatic Nuisance Control Program: Administration of legisla-
tively funded, short-term algal or aquatic weed control
projects.

Assistance/ Staff is funded by a combination of State and Federal money.
Services Matching grants are provided from State funds only or a com-
bination of State and Federal funds. Aquatic nuisance control is
provided with State funds.

Staff 10 (backgrounds in aquatic biology, sanitary biology, fisheries
biology, and geology).

Interactions Public: Extensive response to public requests for grants, sur-
veys and information.
Private: Dealings with consultants and contractors working on
studies and implementation projects.
Governmental: Federal - Clean Lakes Program grants.
State: Cooperation with other DEQE agencies, Division of
Fisheries & Wildlife, and Dept. of Environmental Management.
Local: Grant contracts with communities.

Other Lake- Division of Fisheries & Wildlife: Manages fisheries resources;
Related lake liming program; Department of Environmental Manage-
Programs ment: Manages lakes in State parks; DEQE, Division of Water
Supply: Water supply reservoirs; DEQE, Division of Wetlands:
Wetlands Protection Act.
E-15
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MICHIGAN
Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff

Interactions
Department of Natural Resources
Land and Water Management Division
Inland Lake Management Unit
Box 30028
Lansing, Michigan 48909

The Inland Lake Management Unit serves as a focal point and
information source for lake and watershed management ac-
tivities.

Lake management through the administration of regulatory and
public assistance programs dealing with both specific lakes and
broad lake issues.

1. Aquatic nuisance control: Provide information to the public
on nuisance aquatic macrophyte and algae control and on
swimmer's itch control (including oversight of a research
grant on swimmer's itch control). Responsible for issuing
permits for herbicide use in surface waters.
2. Lake Improvement Boards: Serve as Department of Natural
Resources representatives on Lake Boards formed to under-
take lake restoration/management projects. Boards have
authority to tax riparian owners to fund projects. Currently
there are 60 active boards.
3. Federal Clean Lakes Program: Classification of all lakes over
50 acres was completed in 1982. CLP grants have been ad-
ministered for two demonstration projects, four Phase I
studies, and two Phase II projects.
4. Inland Lake Self-help Monitoring Program: Established in
1974, the program involves volunteers in measuring Secchi
disc transparency. Until 1982 chlorophyll-a was also
measured.
5. Technical reviews: Staff are called on to review (a) NPDES
permit effluent limits for phosphorus discharges to lakes or
within 20 miles upstream of lakes, (b) recommendations on
the establishment of legal lake levels, and (c) dredge and fill
permits which might impact lake water quality.
6. Nonpoint source management: The ILMU provided input
(with the Surface Water Quality Division) to a recently estab-
lished State NPS control incentives grant program.

Public information bulletins and assistance, Self-help Monitor-
ing Program, technical assistance to other agencies.

Combined Federal (50%) and State (50%).
4 (backgrounds in limnology).

Public: Extensive inquires for information from public; work with
Self-help Program volunteers and Lake Boards.
Private: Deal with consultants on Lake Board feasibility studies.
E-16
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Governmental: Federal - EPA Clean Lakes Program.
State: Coordinate with Dept. of Agriculture, Surface Water
Quality Div. (DNR), Engineering-Water Management Div.
(DNR), Fisheries Div. (DNR), and other Div. of Land Resource
Programs units (DNR).

Other Lake- Michigan Department of Agriculture: licensing of herbicides and
Relate herbicide applicators; DNR, Surface Water Quality Division:
Programs NPDES permits & NPS control; DNR, Engineering-Water
Management Division: Lake level control; DNR, Fisheries
Division: Fisheries management; DNR, Division of Land Resour-
ces: Dredge and fill permits.
E-17
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MINNESOTA
Purpose

Emphasis
Program
Elements
Assistance/
Services
Funding
Sources

Staff
Interactions
Minnesota Pollution Control Agency
1935 West County Road/B-2
Roseville, Minnesota 55113

To preserve and protect Minnesota's lakes and to increase and
enhance their public use and enjoyment.

The Minnesota Pollution Control Agency (MPCA) stresses
protection and management through the use of grants on
specific lakes.

1. Minnesota Clean Lakes Program: Since 1977 the MPCA has
administered and supplemented the Federal Clean Lakes
Program. Because the MPCA feels that local leadership, con-
trol and coordination play a key role in a project's success,
most projects are initiated at the local level and the local
project is responsible for implementing the project and meet-
ing the grant objectives. The MPCA evaluates and prioritizes
grant proposals before submitting them to the USEPA,
Region V office. To date, 48 lakes have been involved in the
program.
2. Lake classification: About 1200 of Minnesota's approximately
15,000 lakes have been classified.
3. Routine monitoring: Thirty-five (35) lakes are monitored an-
nually for acid deposition effects and about 100 are
monitored for water quality.
4. Citizen Lakes Monitoring Program: About 285 Lakes are en-
rolled in this program. The MPCA has initiated a pilot
program to assist lake associations in the collection and in-
terpretation of water quality data. Five association are cur-
rently enrolled.
5. Public education: MCPA staff routinely speak to interested
public groups about lake protection. The handbook "Citizens
Guide to Lake Protection" was drafted in conjunction with the
Gray Freshwater Biological Institute and is available for dis-
tribution. The report "Trophic Status of Minnesota Lakes"
provides water quality data on over 1,000 lakes.

Grants and grant administrative assistance are available on re-
quest. Technical expertise and educational materials are avail-
able to respond to public requests and complaints. Citizen
Lakes monitoring Program is available.

Federal for staff and grants. State for grants.

One position to administer the Clean Lakes Program.
Public: Extensive interaction with lake associations and other
public groups.
Private: Consultants dealing with Clean Lakes Program.
Governmental: Federal - USEPA, USDA SCS.
State: DNR, Soil & Water Conservation Board.
Local: Municipalities, etc. managing grants.
Academic: U. Minnesota Limnological Research Center, Gray
Freshwater Institute.
E-18
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MISSOURI
Department of Natural Resources
Division of Environmental Quality
Water Pollution Control Program
P.O. Box 176
Jefferson City, Missouri 65102

To project the beneficial uses listed in the State water quality
standards.

The program acts as a clearinghouse for lake monitoring and
management activities.

Limited review of monitoring and lake management activities of
publicly owned lakes (50 acres).

There are no Federal or State funds specifically available for
lakes.

One limnologist/aquatic biologist available.

Missouri Lakes Association: Gregory W. Knauer (314/421-1476)
Purpose
Emphasis
Program
Elements

Funding
Sources

Staff

Other Lake-
Related
Programs
E-19
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MONTANA
Montana Department of Fish, Wildlife & Parks
1420 East Sixth Avenue
Helena, Montana 59620

Purpose Management of both coldwater and warmwater fisheries.

Program 1. Routine stocking: Trout and salmon are stocked in coldwater
Elements lakes. Walleye, northern pike, and largemouth bass are
stocked in cool/warm-water lakes.
2. Reproducing populations: Considerable effort is being given
to establish reproducing sport fish populations in lakes and
reservoirs of all types; from high mountain lakes to lowland
lakes and from ranch ponds to large ( 200,000 acre) reser-
voirs.
Assistance/
Services

Funding
Sources

Staff

Interactions
None listed.
None listed.
None listed.

Public: None listed.
Private: None listed.
Government: Federal — Army Corps of Engineers, Bureau of
Reclamation.
State: Department of Natural Resources.

Contacts Administrator, Fisheries Division (above address).
George Holton, Asst. Administrator, Fisheries Division (address
above).
E-20
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NEW HAMPSHIRE
Emphasis
Program
Elements
Water Supply and Pollution Central Commission
Biology Division
6 Hazen Drive, P.O. Box 95
Concord, New Hampshire 03301-6528

Purpose To ensure that lakes and ponds with waters superior to estab-
lished standards be maintained at their existing high quality and
to restore those eutrophied lakes which are restorable (technol-
ogy and funding being considered).

Programs primarily focus on research/monitoring of both
specific lake projects and broad topics (acid rain impacts).

1. Lake surveys: Sampling of 40-50 different lakes and ponds,
winter and summer, to provide baseline, long-term trend,
and water quality compliance information.
2. Acid rain studies: Sampling of 20 accessible lake outlets and
about 30 inaccessible ponds (by helicopter) for acid rain
parameters to provide short and long-term trend information
on acid rain effects. Precipitation events are analyzed for pH.
3. Special studies: Intensive lake studies are being conducted
on specific lake problems including (a) algal suppression
using aluminum sulfate (Kezar L); (b) effects of wetlands
manipulation on nutrient removal (Kezar L.); (c) diagnos-
tic/feasibility studies (French and Kezar Ponds), and (d) ef-
fects of causeway construction across Moore Reservoir.
4. Aquatic nuisances: Investigations are made on all citizen
complaints of aquatic nuisances and fishkills; corrective
measures are recommended. If warranted, algaecide-copper
sulfate can be applied to control algal blooms. The Division
also administers the Exotic Weed Control Program which
provides educational materials, eradication of small, new in-
festations, and matching grants to manage existing infesta-
tions.

5. Public education/assistance: Division personnel provide
educational addresses, lake data and acid rain information,
and advice and assistance on developing lake monitoring
programs to interested individuals and groups.

Public education through presentations and written information-
aquatic nuisance control services and grant funds.

Staff is mostly State funded. Aquatic nuisance control is funded
from licensing fees.

5 (aquatic and fisheries biology backgrounds).
Assistance/
Services

Funding
Sources

Staff
E-21
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NEW JERSEY
Department of Environmental Protection
Division of Water Resources
35 Arctic Parkway
Trenton, New Jersey 08638

The division uses a grant aid oriented approach to deal with in-
dividual lake programs.

1. State Grants Aid: Funds provided for Phase I and II type ac-
tivities.
2. Federal Clean Lakes Program: The Division acts as official
applicant and administrator of Federal CLP funds when avail-
able.
3. Herbicide application: Administration of State funds for an-
nual herbicide applications to State owned lakes (about
$50,000/yr; about 12 lakes/yr).

Grant aid for studies, restoration, and herbiciding.
Emphasis
Program
Elements
Assistance/
Services

Funding
Services

Staff

Other Lake-
Related
Programs
Federal CLP (when available) and State budget appropriations
for specific lakes.

One person with experience in lake issues.

New Jersey Division of Coastal Resources.
E-22
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NEW YORK
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Other Lake-
Related
Programs
Department of Environmental Conservation
Bureau of Technical Services and Research
50 Wolf Road
Albany, New York 12233

The program uses a wide variety of methods to address both
project specific and Statewide issues (such as acid precipita-
tion impacts).

1. Financial assistance: State appropriations (about $1.5 mil-
lion) and Federal funds ($100,000) are primarily used on lake
restoration measures such as dredging and harvesting with
lesser amounts spent on watershed work, monitoring, and
research.
2. Citizens Statewide Lake Assessment Program: The DEC con-
ducts this monitoring program using volunteers to aid
general Statewide efforts.
3. Restoration projects: The program conducts and monitors
restoration projects.
4. Fish hatcheries: The DEC operates hatcheries and conducts
a fish stocking program.
5. Public accesses: The Department strives to improve public
access through land acquisition for new sites and develop-
ment of existing facilities (fish piers, boat ramps, etc.)
6. Statewide surveys: Surveys conducted to monitor acid
precipitation impacts and general lake water quality.

Financial and technical assistance.
Federal and State.
6 people in the Central Office (Albany) with backgrounds in en-
vironmental engineering or aquatic biology. Most of the 9
regional offices have a designated Regional Lake Manager.

Local and county Health Departments; County governments:
May conduct restoration or water quality monitoring programs;
Federation of Lake Associations: Public information and citizen
monitoring programs (273 Hollywood Ave., Rochester NY
14618).
E-23
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NORTH CAROLINA
Department of Natural Resources and Community Development
Division of Environmental Management
512 N. Salisbury Street, P.O. Box 27687
Raleigh, North Carolina 27611

Because lake management in North Carolina involves a number of
programs in various agencies, universities, and companies, the following
summary focuses on efforts by the Division of Environmental Manage-
ment but includes other programs.
Program
Elements
Assistance/
Services
1. Lake classification: Surveying and classification of lakes
based on multivariate analysis began in 1981 using Federal
Clean Lakes Program funds. After Federal funds ran out an
ambient monitoring program began and lake trophic indices
were developed. Algal Growth Potential tests done by the
EPA's Ecological Support Branch (Athens, GA aided in
classifying lakes and determining limiting nutrients.
2. Project monitoring: Major sampling efforts are ongoing on
two U.S. Army Corps of Engineer's reservoirs in central
North Carolina (Falls of the Neuse and Jordan Lake) to
evaluate their trophic States and their suitability as raw water
supplies. The U.S.G.S., Army Corps, and universities also
have programs on these reservoirs.
3. Aquatic Weeds Program: This program involves the iden-
tification of aquatic plant problems and the initiation of cor-
rective measures. Hydrilla infestation is a major concern.
4. Lake assessment modelling: Efforts have focused on nutrient
loading from coal fired power plants, and allocation of
oxygen demanding substances to and above lakes and
reservoirs.
5. Watershed controls: An aggressive State/regional/local
program has been developed to control runoff from new
residential and urban development. Agriculture pollution
reduction efforts center on a cost share program to imple-
ment BMPs. A water supply protection program (under
NCDEM) exists to provide protection from point and non-
point sources. The program involves local development of
NPS controls and State limitations on the permitting of point
sources.
6. Public participation: Although no program currently exists
targeting lake management, the Stream Watch Program
(coordinated by the Division of Water Resources) involves
some groups with lake management interests. The program
provides a network of public education and participation in
environmental programs for groups such as schools, com-
munity and fish clubs, Sierra and Audubon chapters, and
river basin associations.

Technical assistance, educational materials.
E-24
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Funding
Sources

Staff
Federal EPA and State legislature.

80-90 people in the NCDEM participate in some way in lake
management, but no one person deals strictly with lake
management.
NORTH DAKOTA
Department of Health
Division of Water Supply & Pollution Control
1200 Missouri Avenue, Box 5520
Bismark, North Dakota 58502-5520

The Department of Health administers a Lake Restoration
Program to provide matching funds for lake protection and
rehabilitation projects.

The program deals with projects on natural and man-made
lakes with public recreational facilities.

Under the Lake Restoration Program grants are provided for
projects designed to reduce lake eutrophication through water-
shed and/or inlake treatments. Eligible project costs include:
construction; construction supervision; administration; equip-
ment and materials; and preparation of construction drawings,
specifications, estimates, & contracts.

State grants of up to 25% of eligible project costs may be made
when Federal funds are available.

Currently the program has $150,000 available for 2 years.
Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Part time, as needed.
E-25
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Emphasis
Program
Elements
Funding
Sources

Staff
OHIO . 1

Environmental Protection Agency
Division of Water Quality Monitoring & Assessment
Northeast District Office
2110 East Aurora Road
Twinsburg, Ohio 44087

Efforts primarily deal with water quality assessment and
prioritization. There is no defined State lake management
program.

1. Lake monitoring/classification: From 1975-80 a cooperative
lake monitoring program with the U.S. Geological Survey
sampled 85 public lakes. Ohio EPA sampled 26 more from
1980-81 as part of a USEPA classification grant. All of these
lakes were prioritized for restoration/protection and for pos-
sible USEPA Clean Lakes Program funding.
2. Federal Clean Lakes Program: Phase I grant on Summit L
3. Ohio Lake Questionnaire: Developed in 1986 to provide the
USEPA Clean Lakes Program with additional information
about priority lakes.
4. State Lakes Policy: Adopted to establish effluent limitations
for point source dischargers to public lakes and reservoirs.
5. Chemical control: Use of chemicals for controlling aquatic
plants or animals requires prior approval of the Ohio EPA.
6. Nonpoint source problems: Cooperative efforts with the Ohio
DNR, county Soil & Water Conservation Districts, and Soil
Conservation Service address using lakes as public drinking
water supplies.

Not listed.
Not listed.
Department of Natural Resources
Fountain Square
Columbus, Ohio 43224

Authorities for the many water management activities relevant to lake
management are spread among several divisions of the ODNR. Each
division is directed toward carrying out individual management respon-
sibilities, particularly involving State-owned lakes. There is no coordinated
lake program. Information on a few of the divisions is summarized below.
Division of Soil & Water Conservation

Emphasis Programs focus on technical assistance/education and on
watershed management activities for both special lake projects
and for problems that potentially affect all surface impound-
ments.
E-26
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Program
Elements
Funding
Sources

Staff
1. Land Inventory & Classification: Wayne Channel! (614/265-
6678)

2. Remote Sensing: Gary Schoal (614/256-6769)
3. Soil & Water Conservation District Assistance: Paul Hoskins
(614/265-6616)

4. Agricultural Pollution Abatement and Urban Sediment Con-
trol: Jerry Wager (614/265-6619)

State general revenues (90%), income from soil surveys,
remote sensing, stc. (7%), Federal grants (3%).

57 (varied backgrounds including soils, agricultural engineer-
ing, agronomy, planning, etc.)
Emphasis
Program
Elements
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff

Other Lake-
Related
Programs
Division of Water

Activities center on public water supply and flood control is-
sues. There is no defined lake management program.

1. Dam safety: Oversees the construction of dam and lakes and
inspects them periodically after completion for public safety.
2. Water resources development: Lake management as it re-
lates to public water supply, whether from surface impound-
ments, streams, or underground aquifers.
3. Flood control: Coordination of activities with Federal agen-
cies to construct flood control lakes. Other activities are
aimed at reducing flood damages.

Division of Wildlife

Programs are designed on a species management basis but the
methods often benefit lakes.

1. Resource management: Methods used include: harvest
regulations, stocking fish, aquatic vegetation control, dredg-
ing, water level manipulation, lake renovation, fish species
rehabilitation, fertilization, and environmental assessment.
2. Resource utilization: Development of angler access/facilities
(parking, ramps, docks, piers, etc.) and public communica-
tion about fishing opportunities.
3. Public communication: Advise the public using public meet-
ings, correspondence, publications, news media, and per-
sonal contact.

Technical and educational assistance to support angler ac-
tivities.

Primarily funded from the sale of State fishing licenses; some
Federal aid funds (Dingell-Johnson).

About 100 (backgrounds mainly in fisheries science).

ODNR, Division of Parks and Recreation; ODNR, Division of
Watercraft; Ohio Lake Management Society, Elizabeth L
Buchanan (216/673-8272)
E-27
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OREGON
Emphasis
Program
Elements
Assistance/
Services
Funding
Sources

Staff
Department of Environmental Quality
Executive Building
811 SW Sixth Avenue
Portland, Oregon 97204

The State's program is fairly small and tailored towards the
Federal Clean Lakes Program. Projects are aimed at problems
in specific lakes.

Specific projects are managed according to the Federal Clean
Lakes Program guidelines. They seek solutions for long-term
control of weeds, nutrient inputs, and improving flow and water-
shed management.
Currently there are two projects. Devils Lake in Lincoln City has
a nuisance aquatic weed problem and Sturgeon Lake in N.
Portland has an excessive sedimentation problem.

Coordination and management of Federal Clean Lakes
Program grants; sampling and technical guidance to local com-
munities.

Primarily Federal Clean Lakes Program funds.
1 part-time (limnology/environmental assessment background).
E-28
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PENNSYLVANIA
Department of Environmental Resources
Bureau of Water Quality Management
P.O. Box 2063
Harrisburg, Pennsylvania 17120

To provide for a consistent and effective Statewide approach to
controlling nutrients (phosphorus) to impounded waters so as
to maintain an acceptable trophic level which will not adversely
impact on designated water uses.

The program focuses on regulatory issues as they affect in-
dividual priority lakes. Some technical input and funding are
provided for broader issues (nonpoint source control and acid
deposition).

1. Regulation of phosphorus discharges to lakes, ponds, and
impoundments: The regulations provide a systematic
method for protecting lakes and impoundments that are un-
dergoing eutrophication. It relies on empirical lake models to
estimate phosphorus loadings and to determine the ap-
propriate level of protection or water quality improvement,
considering both point and nonpoint sources.
2. Data acquisition: Conduct lake surveys to obtain data which
support the imposition of phosphorus controls on waste-
water discharges.
3. Federal Clean Lakes Program: Coordinate the CLP with inter-
ested and qualified lake watershed management districts or
organizations within the State.

Technical guidance on request
Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Source

Staff

Other Lake-
Related
Programs
Combination of Federal and State.
8 (backgrounds in water pollution biology/ecology).

DER, Bureau of State Parks: Lake treatment program for State
park lakes.
E-29
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SOUTH CAROLINA
Department of Health and Environmental Control
Bureau of Water Pollution Control
2600 Bull Street
Columbia, South Carolina 29201

The Department (SCDHEC) has no particular agency or staff responsible
solely for lake management. Issues relating to lake quality and manage-
ment are dealt with as part of program areas which have a larger overall
function.
Program
Elements
Other Lake-
Related
Programs
1. Water quality sampling: Extensive sampling is conducted on
the major lakes and special intensive surveys are conducted
to evaluate specific water bodies.
2. Classification: All of the State's lakes are actually reservoirs
created for electrical power. They are classified for primary
recreation (highest freshwater category excluding trout
habitat) and management strategies are developed based on
that classification.
3. Other elements involve wastewater discharge permits, water
quality standards, and general water quality management
strategies.
4. Reservoir management: Management of the major reservoirs
is by the organization which holds the license for its opera-
tion.
a. Duke Power Co. (P.O. Box 33189, Charlotte, NC 28242)
L Socasse, L. Keowee, L. Wylie, L Greenwood, L Wateree,
L. Robinson.
b. U.S. Army Corps of Engineers (P.O. Box 899, Savan-
nah, GA 31402) Hartwell R., Clark Hill R.
c. S.C. Electric & Gas (Palmetto Center, 1420 Main St.,
Columbia, CS 29201) L. Murray, Montecello R.
d. Public Service Authority (P.O. Box 398, Moncks Corner,
SC 29461) L Marion, L Moultrie.

Dept of Wildlife & Marine Resources: Manages lake fisheries;
Water Resources Commission: Manages resource quantity.
E-30
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TENNESSEE

Department of Health and Environment
Division of Water Pollution Control
1605 Prosser Road
Knoxville, Tennessee 37914-3434

Emphasis The program is primarily focused at regulatory issues of water
quality management including numerous TVA impoundments
(i.e., Statewide scope). Research efforts are toward program
support and enforcement.

Program 1. Water quality regulation.
Elements 2. Implementation and enforcement of the Tennessee Water
Quality Control Act.
3. NPDES primacy for State and Federal facilities and coal min-
ing.
4. Certifying agency for the 404 process.
5. Permitting: Wetlands, non-coal mining, and habitat alteration.

Assistance/ Technical cooperation with other agencies.
Services
Funding
Sources

Staff
Mainly Federal with some State appropriations.
About 130 (backgrounds in engineering, biology, geology, and
water quality).
E-31
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I UTAH 1

Department of Natural Resources
Division of Wildlife Resources
1596 West North Temple
Salt Lake City, Utah 84116

Emphasis The program focuses on solving individual lake problems, but
some work is done on problems of a broader scope (acid
deposition). Some research is also done.

Program 1. Fisheries management: Aspects of this program deal with:
Elements predator-prey relations; exploitation; trout strain evaluations;
recovery of native trout populations; recovery or develop-
ment of black bass populations; studies to determine trout
stocking rates, times, and sizes; chemical renovation;
population monitoring; and development of management
plans.
2. Acid deposition: Management of 650 soft water lakes in the
High Uintas region which could be affected by acid deposi-
tion.
3. Trout research: Limited study of sterile and hybrid trout.

Funding Mainly funded from fishing license sales and Federal aid (Wai-
Sources lup-Breaux).

Staff About 27 full-time in fisheries management (backgrounds in
fisheries science). Most spend 2% of their time on lake manage-
ment.

Other Lake- Utah Department of Health: Richard Denton; Bureau of
Related Reclamation: Jerry Miller; Utah State Cooperative Fisheries
Programs Unit: Tim Modde; Utah State University: Wayne Wurtsbaugh
E-32
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VERMONT
Department of Water Resources & Environmental Engineering
Water Quality Division
103 South Main Street
Waterbury, Vermont 05676

Purpose The Lakes and Ponds Program is responsible for planning and
managing in the best public interest all activities dealing with
Vermont's lakes.

Emphasis The primary objective is to assure the maximum sensible
recreational potential of lakes through sound water quality
management practices.

Program 1. Monitoring and surveillance: The Department keeps abreast
Elements of existing lake water quality conditions and detects changes
in lake quality conditions through the following four data col-
lection programs.
a. Spring Phosphorus Program: Sampling once a year in
the spring to monitor a large number of lakes for trends in
total phosphorus which may indicate impending water
quality problems.
b. Acid Deposition Program: This program collects chemi-
cal and biological data on lakes located in low alkalinity
(acid-sensitive) regions of the State to determine the effects
of acid deposition.
c. Lay monitoring Program: Equipment and training are
provided under this program so that local residents may col-
lect lake water quality data during the summer. Secchi disk
transparency, chlorophyll-a and total phosphorus (on Lake
Champlain only 4) data obtained from these collections allow
the Department to follow trends in the water quality of Ver-
mont lakes.
d. Summer Lakes Program: Basic water quality informa-
tion (shoreline bacterial samples, dissolved oxygen and
temperature profiles, and Secchi disk transparency) is col-
lected monthly on 25-30 lakes during the summer. Detailed
aquatic plant surveys are conducted on a limited number of
lakes.
2. Studies: For various reasons a specific lake may be chosen
for detailed water quality study. Lake studies may involve
long-term extensive data collection or limited data collection
and sophisticated lake modelling techniques. Studies have
been funded through the Federal Clean Lakes Program
and/or State funds.
3. Management/restoration activities: Lakes with water quality
problems may undergo either maintenance activities or res-
toration activities. Maintenance activities are control
measures to manage aquatic nuisances on a yearly basis.
Restoration activities are aimed at eliminating causes to lake
problems in order to achieve long-term benefits. Main-
tenance efforts currently underway include the Lake
Champlain Aquatic Nuisance Control Program (harvesting of
E-33
-------
Assistance/
Services

Funding
Sources
Staff
water chestnut and Eurasian milfoil) and the Aquatic
Nuisance Control Program (nuisance control in other lakes).
Restoration projects have been dealt with through the CLP
(both studies and implementation) and the U.S. Soil Conser-
vation Service (agricultural best management practices).
4. Lake Protection Program: Lake protection is promoted
through (a) monitoring and surveillance (described above),
(b) educational activities (a slide show has been completed;
brochures and short workshops are planned), and (c)
regulation.
The Management of Lakes and Ponds Statute (permitting of
encroachment into waters), the Phosphate Detergent Ban,
the Water Quality Standards, and the Land Use Control Law
provide regulatory protection mechanisms.

Technical and educational assistance; grant aid for restoration
and maintenance projects.

Federal funds are provided for grants through the EPA (Clean
Lakes Program) and Army Corps of Engineers (Lake Champlain
Aquatic Nuisance Control). The State legislature provides other
funds.

4 full-time (backgrounds in limnology, biology/botany, and en-
vironmental education), 2 part-time (statistics and administra-
tion), and 5 seasonal.
E-34
-------
VIRGINIA
Emphasis
Program
Elements
Water Control Board
2111 Hamilton Street, P.O. Box 11143
Richmond, Virginia 23230-1143

The Program centers on monitoring publicly owned lakes to
determine lake trophic States and accelerated eutrophication
problems.

1. Lake Monitoring Program: 15 to 20 publicly owned lakes are
tested each year for general water quality parameters. Data
are used to update trophic status information which was
originally obtained under an EPA Clean Lakes Program clas-
sification grant.

2. Federal Clean Lakes Program: Three lakes (L Accotink, L.
Chesdin, and Rivanna R.) and receiving Phase II funding.
3. Lay monitoring: The VWCB assists volunteer sampling efforts
by identifying algal samples.

Technical assistance on sampling methods and algal identifica-
tion; educational materials.

Primarily Federal (106) with minor State appropriations.
Assistance/
Services

Funding
Sources

Staff
Other Lake-
Related
Programs
One person (environmental specialist) oversees the Lake
Monitoring Program which is carried out by 1-2 people in each
of 6 regional offices. They have biology, chemistry, and environ-
mental analysis backgrounds.

Occoquan Watershed Monitoring Laboratory: Water quality as-
sessment in the suburban Washington, D.C. area.
E-35
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WASHINGTON
Purpose
Emphasis
Department of Ecology
Mail Stop PV-11
Olympia, Washington 98504-8711

The Department's lake restoration program endeavors to re-
store to lakes those beneficial uses that have been lost or im-
paired in the recent past (i.e., 50 years).

The program is primarily grant-aid oriented toward individual
problem lakes with public access. Some amount of applied re-
search is accomplished indirectly from grant projects and some
of the developments of these projects can be applied to other
lakes with similar projects.

1. Diagnostic/Feasibility Studies (Phase I): Develops a water
and nutrient budget, identifies water quality problems and
their causes, and recommends restoration alternatives. Cost
estimates for the proposed Phase II project are developed
and an environmental assessment may be prepared.
2. Implementation Projects (Phase II): Implements the findings
and recommendations of Phase I.

Grants of up to 75% of total project costs to public entities;
technical assistance on limnological questions, study require-
ments, lake associations, organizational assistance, aquatic
macrophyte control, etc.

Primarily State funds matched by local resources.
Program
Elements
Assistance/
Services
Funding
Sources

Staff
1 full-time and 2 half-time people.
Other Lake- Washington Department of Game (600 N. Capitol Way, Olym-
Related pia, WA 98504).
Programs
E-36
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WISCONSIN
Purpose
Emphasis
Program
Elements
Assistance/
Services
Funding
Sources

Staff
Other Lake-
Related
Programs
Department of Natural Resources
P.O. Box 7921
Madison, Wisconsin 53707-7921

To protect and maintain Wisconsin's lake resources for our own
and future generations; to help carry out measures that protect
and maintain lakes; and to strive for active coordination be-
tween the many government programs and personnel that work
on lakes.

The program guides local lake management organizations
across the State in planning and carrying out a variety of lake
protection measures including soil and water conservation, lake
user education and advocacy for local protective regulations.

1. Outreach and technical assistance: Day-to-day guidance to
lake property owners on how to identify needs, find and in-
terpret lake/watershed information, and evaluate manage-
ment alternatives. Each year local actions are promoted on
"key lakes" that need special protection.
2. Self-help monitoring: Volunteers are trained to measure water
clarity and lake levels. Each year the volunteers receive an
interpretation of their lake data and a Statewide summary
report. Their data provide the DNR with long term data on a
larger number of lakes than it could survey.
3. Education activities: In conjunction with the University of Wis-
consin-Extension the DNR provides water quality informa-
tion to help lake property owners. Assistance is available
through conventions, workshops, field days, and publica-
tions (such as: "The Lake in Your Community;" "Lake Tides,"
a newsletter; and "A Guide to Lake Management Law.")
4. Trend monitoring: Fifty (50) representative lakes across the
State are monitored for physical, chemical, biological, and
watershed changes. Analyses of these data are used as an
evaluation tool to compare lakes Statewide and to provide
policy directions.
5. Research and demonstration projects: The intent of this ele-
ment is to develop, test, and demonstrate lake protection
and management techniques which can be used by local or-
ganizations.

Technical guidance for public requests on lake problems. Train-
ing in water quality monitoring for the self-help program. Educa-
tional materials.

State.
10 (6 lake management coordinators in 6 DNR district offices; 4
staff members in the Central Office with expertise in organiza-
tion/planning, engineering, limnology, and hydrogeology).

None listed.
E-37
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WYOMING
Department of Environmental Quality
Water Quality Division
Herschler Building/4th Floor W.
Cheyenne, Wyoming 82002

Due to the lack of Federal Clean Lakes Program funds for new projects
Wyoming's lake program is currently inactive. There are, however, several
problem lakes which need attention.
Canadian Provinces
ALBERTA
Alberta Forestry, Lands and Wildlife
Fish & Wildlife Division
North Tower, Petroleum Plaza
9945-108 Street
Edmonton, Alberta T5K 2G6

Purpose The program is oriented toward the management and produc-
tion of fish populations in individual lakes.

Program 1. Lake habitat inventories: Surveys provide data on basic mor-
Elements phometry, water chemistry and existing fish populations to
determine fish populations using regulations and fish stock-
ing programs.
2. Management of fish populations using regulations and fish
stocking programs.

Assistance/ Providing information on lake characteristics, critical fish
Services habitats, fish populations, fish production and fisheries utiliza-
tion to anglers, consultants and government agencies.

Funding Funds are mainly from the provincial government. Part of Angler
Sources License fees go to a habitat development program.

Staff 26 people (mainly fisheries background; some with wildlife
management experience).

Other Lake- Alberta Environment: Water resources management, water
Related quality control, environmental impact assessment; Alberta
Programs Forestry, Lands and Wildlife-Land Division: Shorelands and ac-
cess; Forestry: Public access and recreation facilities (public
land); Wildlife: Fisheries and wildlife matters; Alberta Municipal
Affairs: Shoreland and access (non-public lands).
E-38
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MANITOBA
Emphasis
Department of Natural Resources
Fisheries Branch
1495 St. James Street, P.O. Box 40
Winnipeg, Manitoba R3H OW9

The program is primarily management (regulation/rehabilita-
tion) oriented; dealing with both point (industrial pollutants and
feedlot runoff) and nonpoint source (agriculture and forest ac-
tivities) pollution. Some small grants are provided for aeration
assistance and experimental design of aeration techniques.

1. Winter oxygen monitoring and aeration.
2. Riparian land use control

3. Consultative role on environmental assessments of develop-
ments causing point and nonpoint pollution.
4. Chemical algae control.

5. Recommendations on instream flows and lake/reservoir level
strategies.

6. Controlling instream alteration (channelization) affecting
sediment loading.

Consultative services; grants and technical assistance for aera-
tion installations.

Provincial.
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Other Lake-
Related
Programs
9 fisheries biologists spend a portion (5-40%) of their time on
lake management issues.

Manitoba Environment, Workplace Safety and Health (139
Tuxedo Blvd., Winnipeg, Manitoba R3N OH6).
E-39
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NEW BRUNSWICK
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Other Lake-
Related
Programs
Department of Natural Resources & Energy
Fish and Wildlife Branch
P.O. BoxGOOO
Federicton, New Brunswick E3B 5H1

The Department's lake program is management oriented; deal-
ing with broad management problems, but characterizing lakes
as to specific species management.

1. Data acquisition and storage: Lakes with public access are
surveyed on a priority basis. Once a lake has been surveyed,
the data is entered into a computer database (Fish Lake) for
storage and retrieval. Computer programs are also available
on fish age, growth and populations, and lake productivity.
2. Management determinations: Lake and associated stream
data are used to determine limiting factors and lake manage-
ment options. Lakes are also characterized into target
species lakes (brook trout, landlocked salmon, lake trout,
small mouth bass, and pickerel).
3. Stocking program: Lakes are stocked based on management
determinations.

Public information on angling, size location, depths, water
quality, and species compositions.

Provincial general revenues are administered through the Fish
& Wildlife Branch and 5 forest regions.

Chief Fisheries Biologist, Hatchery Biologist, Habitat Biologist,
Cold Water Biologist, and 5 regional fisheries biologists along
with field support staff.

Provincial Department of Municipal Affairs & Environment;
Federal Department of Fisheries & Oceans; Federal Department
of Environment
E-40
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NEWFOUNDLAND
Department of Environment
Water Resources Management
St. Johns, Newfoundland

The department has expertise and policies dealing with problems regard-
ing issues as water quality and water pollution.
No other information available at this time.
Contact: Wasi Ullah, Director
Other Lake-
Related
Programs
Department of Fisheries & Oceans; Department of Environment
Canada
NOVA SCOTIA
Department of Fisheries Division
P.O. Box 700
Pictou, Nova Scotia BOK 1 HO

Purpose As a result of the 1982 Federal-Provincial Agreement on Trout,
the Division has been provided with the responsibility for aug-
mentation and restoration of the recreational trout fishery.

Emphasis The Management Plan focuses on management and enhance-
ment of the recreational trout fishery so as to provide maximum
benefit to trout anglers, present and future.

Program 1. Habitat: In cooperation with the Nova Scotia Department of
Elements Environment and the Federal Department of Fisheries and
Ocean's fish habitats are assessed, monitored, and
protected through (a) close cooperation and review of inter-
nal activities and programs with potential impacts on habitat,
(b) active survey and assessment programs for better
delineation of usable habitat, (c) implementation of long-
term habitat improvement programs (stream clearing,
stream stabilization devices, erosion/sediment control,
flowage stabilization devices, etc.).
2. Production: Hatchery production of trout fall fingerlings and
yearlings has been greatly accelerated at three departmental
hatcheries.
3. Research: To maximize the effectiveness of both artificial and
natural productions, research will be conducted in the fol-
lowing areas.
a. Improved broodstock genetics (long-term survivorship,
diseases resistance, fish quality, etc.).
b. Post-distribution impact assessments of hatchery
stocked fish on natural populations (disease susceptibility,
genetic pollution, behavior, long-term wild population
dynamics, etc.).
E-41
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c. Effect of predator fish species on natural and stocked
fish populations and how to ameliorate predator imbalances
(chemical poisoning, habitat manipulation, stock manipula-
tion, angling, physical removal, etc.).
d. Identifying environmental limitations for natural recruit-
ment and stock introductions.
e. Developing criteria for the creation of specific angler op-
portunities.
f. Developing mechanisms and criteria for the enhance-
ment of sea-run fisheries to create better Province-wide
fisheries opportunities, specifically inland waters with iden-
tified natural limitations.
4. Management: Development of a long-term Management Plan
to include (a) zonation of the Province based on environ-
mental, stock, and user group consideration, (b) regulatory
management through joint initiatives of user groups and the
Department, (c) identification and conservation of unique
sustainable wild trout populations, and d) establishment of
zone committees whose responsibilities would include
recommendation and assessment of special management
initiatives.
5. Enforcement: Work closely with enforcement agencies (DFO
and Dept. of Lands & Forests) to ensure that management
initiatives are monitored and enforced in each zone.
6. Education: To ensure that the public is fully informed and in-
volved in the wise stewardship of its inland fisheries, the
Department will (a) prepare brochures, films, videos, techni-
cal/scientific reports, etc. on fishery related topics, (b) ensure
attendance at meetings to provide exchange of information,
and (c) involve public groups in enhancement projects (con-
structing of artificial reeds and streamside incubators).
E-42
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ONTARIO
Emphasis
Program
Elements
Ministry of Natural Resources
Fisheries Branch
Whitney Block, Queen's Park
Toronto, Ontario M7A 1W3

Most programs and projects are geared towards management,
although there are some research and assessment projects.
Some grant aid is available for public involvement programs. In-
dividual problem lakes are addressed as well as large numbers
of lakes where broader problems are perceived.

1. Fisheries management: Methods include: habitat inventory,
habitat rehabilitation, habitat enhancement, and fisheries re-
search and assessment.
2. Water quality monitoring: Extensive water chemistry surveys
have been done on thousands of lakes and integrated into
databases. Numerous programs for lake research and
monitoring have developed from the acid rain problem.
3. Self-help programs: The public can receive information and
assistance through local Ministry of Natural Resources
(MNR) and Ministry of Environment offices. Typical services
include: drinking water potability testing, septic tank inspec-
tions, and fish management information.
4. Public participation: Programs developed toward public par-
ticipation include (a) the Community Fisheries Involvement
Program (CFIP) which stresses habitat improvement and
conservation of fish stocks and (b) the newly initiated
Shoreline Restoration Program whereby the MNR has
cooperated with lake associations in running their own nur-
series and revegetating lake shorelines to form natural buffer
strips.

Self-help and public participation programs; technical assis-
tance; educational information; grant aid for CFIP.

Regular provincial budget funds.
Assistance/
Services

Funding
Sources

Other Lake
Related
Programs
Ministry of Environment, Acid Rain Program: Wayne G. Scott
(416/965-2214); Ministry of Environment, Acid Precipitation Of-
fice, 6th Floor, 4-St. Clair Avenue W., Toronto, Ontario
M4V1M2); Federation of Ontario Cottagers Association (FOCA)
Albert O. Shingler (416/284-2305; FOCA, 215 Morrish Road
#105, Scarborough, Ontario M1C 1E9)
E-43
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QUEBEC
Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Other Lake
Related
Programs
Ministere du Losir, de la Chasse et la Peche
Direction generale de la faune
150est, boul. Saint-Cyrille
Quebec, QCG1R4V1

The objectives of the Ministry of Leisure, Hunting, and Fishing
are resource conservation and optimization of social and
economic benefits of fish exploitation (native, sport, and com-
mercial).

The program is oriented toward management of fisheries. In-
dividual lake problems are dealt with at the regional offices and
the central office (Quebec City) works on broader issues. A
small portion of the program deals with short-term (1 -3 yrs) re-
search on "applied" problems.

1. Exploitation control zone (ZEC): Sport fishing control and
management are delegated to public associations in special
areas (ZECs). Assistance (expertise and money) is provided
through the regional offices to sport fishing associations (in
the ZECs of in non-organized territories).
2. Stocking program: Fish are stocked in areas of demand
(mostly brook trout).
3. Habitat conversation: This occurs through analysis of impact
assessment study reports and cooperation with the Ministry
of Environment.
4. Broad scope problem studies are done on areas such as:
acidification effects on walleye, lake trout exploitation, and
interspecific competition between brook trout and other
species.

Technical assistance; grants for developing sport fishing or
managing fish habitat.

Provincial.
About 30 biologists and 70 natural resources technicians are
spread among 10 regional offices. Ten biologists and 5 tech-
nicians work at the central office (Quebec City).

Ministry of Environment: Pollution control, environmental im-
pact studies, acid precipitation, etc; Ministry of Energy &
Resources: Forest exploitation, recreational development of
public lands around lakes; Ministry of Agriculture, Fisheries, and
Alimentation: Inland commercial fisheries; Hydro Quebec-
Development and operation of hydroelectric projects and
development of fisheries resources in reservoirs.
E-44
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SASKATCHEWAN
Purpose
Emphasis
Program
Elements
Assistance/
Services

Funding
Sources

Staff
Other Lake
Related
Programs
Saskatchewan Parks and Renewable Resources
Fisheries Branch
Box 3003
Prince Albert, Saskatchewan S6V 6G1

To maintain and enhance fish supplies, ensure an adequate
supple and variety of fish which will meet the needs of the major
user groups, and maximize the contribution of the fisheries sec-
tor to the provincial economy.

The program focuses on fisheries management using a broad
issue approach (e.g., there are 3 management zones for sport
fish conservation measures). Regulations and activities can be
lake specific.

1. Sport fish stocking: Stocking is used to maintain, enhance
and diversify sport fisheries in the southern half of the
Province. In the north, conservation measures are relied
upon to maintain fish populations.
2. Fisheries enhancement: Conservation and enhancement
measures are used to maintain and rebuild fisheries. Fish en-
hancement projects include: rearing ponds, lake aeration,
fishways, and habitat improvement. Funds are available to
help conservation groups in these activities.

Funds for fish enhancement; stocking.

Primarily government funded except the Fish Enhancement
Fund which is from angling license fees.

42 permanent (mostly with background in fisheries biology)-18
casual/part time.

Department of Environment: Environmental impact studies pol-
lution control, etc; Saskatchewan Water Corporation: Oversees
all aspects of water management; Resource Lands Branch
(Saskatchewan Parks and Renewable Resources): Oversees
man's development around water (e.g., recreational sub-
divisions) and on Crown land.
E-45
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Appendix F
Editor's Note:
These forms and documents are to be considered as examples ONLY!
Any person or organization who is considering contracting for services
should have an attorney draft the proper contracts within a given jurisdic-
tion.
Safety
Safety and protection of workers, lake property owners and observers is
paramount. The following example of contract document is included to give the
reader some background on what should be specified in contracts as well as
citations to work hours and safety standards. Individual contracts will have to be
developed locally by the sponsoring agency, local government offices and
property owners with exact work specifications written out to insure compliance
and orderly progression of the implementation of the lake restoration project.
The following example was taken from a lake restoration project in the State of
Washington.

• PROTECTION OF WORK, PROPERTY, AND PERSONS. The CONTRAC-
TOR will be responsible for initiating, maintaining and supervising all safety
precautions and programs in connection with the WORK and all materials or
equipment to be incorporated therein, whether in storage on or off the site, and
other property at the site or adjacent thereto, including trees, shrubs, lawns,
walks, pavements, roadways, structures and utilities not designated for removal,
relocation or replacement in the course of construction.
The CONTRACTOR will comply with all applicable laws, ordinances, rules,
regulations, and orders of any public body having jurisdiction. He will erect and
maintain, required by the conditions and progress of the WORK, all necessary
safeguards for safety and protection. He will notify owners of adjacent utilities
when prosecution of the WORK may affect them. The CONTRACTOR will
remedy all damage, injury or loss to any property caused, directly or indirectly,
in whole or in part, by the CONTRACTOR, any SUBCONTRACTOR or anyone
directly or indirectly employed by any of them or anyone for whose acts any of
them be liable, except damage or loss attributable to the fault of the CONTRACT
DOCUMENTS or to the acts or omissions of the OWNER or the ENGINEER or
anyone employed by either of them or anyone for whose acts either of them may
be liable, and not attributable, directly or indirectly, in whole or in part, to the
fault or negligence of the CONTRACTOR.
In emergencies affecting the safety of persons or the WORK or property at the
site or adjacent thereto, the CONTRACTOR, without special instruction or
authorization from the ENGINEER or OWNER, shall act to prevent threatened
damage, injury or loss. He will give the ENGINEER prompt WRITTEN NOTICE of
any significant changes in the WORK or deviations from the CONTRACT DOCU-
MENTS caused thereby, and a CHANGE ORDER shall thereupon be issued
covering the changes and deviations involved.

• SUPERVISION BY CONTRACTOR. The CONTRACTOR will supervise and
direct the WORK. He will be solely responsible for the means, methods, techni-
ques, sequences and procedures of construction. The CONTRACTOR will
F-1
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employ and maintain on the WORK a qualified supervisor or superintendent who
shall have been designated in writing by the CONTRACTOR as the
CONTRACTOR'S representative at the site. The supervisor shall have full
authority to act on behalf of the CONTRACTOR and all communications given to
the supervisor shall be as binding as if given to the CONTRACTOR. The super-
visor shall be present on the site at all times as required to perform adequate su-
pervision and coordination of the WORK.

• CHANGES IN THE WORK. The OWNER may at any time, as the need arises,
order changes within the scope of the WORK without invalidating the Agree-
ment. If such changes increase or decrease the amount due under the CON-
TRACT DOCUMENTS or the time required for performance of the WORK, an
equitable adjustment shall be authorized by CHANGE ORDER.
The ENGINEER, also, may at any time, by issuing a FIELD ORDER, make
changes in the details of the WORK. The CONTRACTOR shall proceed with the
performance of any changes in the WORK so ordered by the ENGINEER unless
the CONTRACTOR believes that such FIELD ORDER entitles him to change in
CONTRACT PRICE or TIME, or both, in which event he shall give the ENGINEER
WRITTEN NOTICE thereof within seven (7) days after the receipts of the ordered
change. Thereafter the CONTRACTOR shall document the basis for the change
in CONTRACT PRICE or TIME within thirty (30) days. The CONTRACTOR shall
not execute such changes pending the receipt of an executed CHANGE ORDER
or further instruction from the OWNER.

• CHANGE IN CONTRACT PRICE. The CONTRACT PRICE may be changed
only by a CHANGE ORDER. The value of any WORK covered by a CHANGE
ORDER or of any claim for increase or decrease in the CONTRACT PRICE shall
be determined by one or more of the following methods in the order of
precedence listed below:
(a) Unit prices previously approved.
(b) An agreed lump sum.
(c) The actual cost for labor, direct overhead, materials supplied, equipment,
and other services necessary to complete the work. In addition, there shall be
added an amount to be agreed upon but not to exceed fifteen (15) percent of the
actual cost of the WORK to cover the cost of general overhead and profit.

• TIME FOR COMPLETION AND LIQUIDATED DAMAGES. The date of
beginning and the time for completion of the WORK are essential conditions for
the CONTRACT DOCUMENTS and the WORK embraced shall be commenced
on a date specified in the NOTICE TO PROCEED.
The CONTRACTOR will proceed with the WORK at such rate of progress to
insure full completion within the CONTRACT TIME. It is expressly understood
and agreed, by and between the CONTRACTOR and the OWNER, that the CON-
TRACT TIME for the completion of the WORK described herein is a reasonable
time, taking into consideration the average climatic and economic conditions
and other factors prevailing in the locality of the WORK.
If the CONTRACTOR shall fail to complete the WORK within the CONTRACT
TIME, or extension of time granted by the OWNER, then the CONTRACTOR will
pay to the OWNER the amount for liquidated damages as specified in the BID for
each calendar day that the CONTRACTOR shall be in default after the time stipu-
lated in the CONTRACT DOCUMENTS.
The CONTRACTOR shall not be charged with the liquidated damages or any
excess costs when the delay in completion of the WORK is due to the following
and the CONTRACTOR has promptly given WRITTEN NOTICE of such delay to
the OWNER or ENGINEER.
F-2
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• CONTRACT WORK HOURS AND SAFETY STANDARDS ACT - SAFETY
AND HEALTH. The CONTRACTOR shall not require any laborer or mechanic
employed in the performance of the contract to work in surroundings or under
working conditions which are unsanitary, hazardous or dangerous to his health
or safety, as determined under construction safety and health standards promul-
gated by regulations of the Secretary of Labor.
The CONTRACTOR shall comply with the Department of Labor, Safety and
Health Regulations for Construction promulgated under section 107 of the Con-
tract Work Hours Safety Standards Act (40 U.S.C. 327 et seq.).
BID BOND
KNOW ALL MEN BY THESE PRESENTS, that we, the undersigned,

as Principals,

and as Surety, are hereby held and

firmly bound unto as OWNER in the

penal sum of for the payment of which,

well and truly to be made, we hereby jointly and severally bind ourselves succes-

sors and assigns.

Signed, this day of , 19 .
The Condition of the above obligation is such that whereas the Principal has

submitted to a certain BID, attached
hereto and hereby made a part hereof to enter into a contract in writing, for

the
NOW, THEREFORE,
(a) If said BID shall be rejected, or
(b) If said BID shall be accepted and the Principal shall execute and deliver a
contract in the Form of Contract attached hereto (properly completed in accord-
ance with said BID) and shall furnish a BOND for his faithful performance of said
contract, and for the payment of all persons performing labor or furnishing
materials in connection therewith, and shall in all other respects perform the
agreement created by the acceptance of said BID,
then this obligation shall be void, otherwise the same shall remain in force
and effect; it being expressly understood and agreed that the liability of the
Surety for any and all claims hereunder shall, in no event, exceed the penal
amount of this obligation as herein stated.
The Surety, for value received, hereby stipulates and agrees that the obliga-
tions of said Surety and its BOND shall be in no way impaired or affected by an
extension of the time within which the OWNER may accept such BID; and said
Surety does hereby waive notice of any such extension.
IN WITNESS WHEREOF, the Principal and the Surety have hereunto set their
hands and seals, and such of them as are corporations have caused their cor-
porate seals to be hereto affixed and these presents to be signed by their proper
officers, the day and year first set forth above.
F-3
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(LS.)
Principal
Surety

By:

PROVIDED, FURTHER, that the said Surety for value received hereby stipu-
lates and agrees that no change, extension of time, alteration or addition to the
terms of the contract or to the WORK to be performed thereunder of the
SPECIFICATIONS accompanying the same shall in anywise affect its obligation
on this BOND, and it does hereby waive notice of any such change, extension of
time, alteration or addition to the terms of the contract or to the WORK or to the
SPECIFICATIONS.
PROVIDED, FURTHER, that no final settlement between the OWNER and the
CONTRACTOR shall abridge the right of any beneficiary hereunder, whose claim
may be unsatisfied.

IN WITNESS WHEREOF, this instrument is executed in counter-

parts, each one of which shall be deemed an original, this the

day of , 19 .

ATTEST:
Principal
(Principal) Secretary
(SEAL) By (s)
(Address)
Witness as to Principal

(Address)
Surety

ATTEST by (s)
Witness as to Surety (Address)
(Address)
NOTE: Date of BOND must not be prior to date of Contract. If CONTRACTOR
is Partnership, all partners should execute BOND.
IMPORTANT: Surety companies executing BONDS must appear on the
Treasury Department's most current list (Circular 570 as amended) and be
authorized to transact business in the State where the PROJECT is located.
F-4
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PAYMENT BOND
KNOW ALL MEN BY THESE PRESENT: that
(Name of Contractor)
(Address of Contractor)
_, hereinafter called Principal, and
(Corporation, partnership or individual)
(Name of Surety)
(Address of Surety)
hereinafter called Surety, are held and firmly bound unto
(Name of Owner)
(Address of Owner)

hereinafter called OWNER, in the penal sum of Dollars,
$( ) in lawful money of the United States, for the payment of which sum well
and truly to be made, we bind ourselves, successors, and assigned, jointly and
severally, firmly by these present.
THE CONDITION OF THIS OBLIGATION is such that whereas, the Principal
entered into a certain contract with the OWNER, dated the
day of 19 , a
copy of which is hereto attached and made a part hereof for the construction of:
NOW, THEREFORE, if the Principal shall promptly make payment to all per-
sons, firms, SUBCONTRACTORS, and corporations furnishing materials for or
performing labor in the prosecution of the WORK provided for in such contract,
and any authorized extension or modification thereof, including all amounts due
for materials, lubricants, oil, gasoline, coal and coke, repairs on machinery,
equipment and tools, consumed or used in connection with the construction of
such WORK, and all insurance premiums on said WORK, and for all labor per-
formed in such WORK whether by SUBCONTRACTOR or otherwise, then this
obligation shall be void; otherwise to remain in full force and effect.
F-5
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PROVIDED, FURTHER, that the said Surety for value received hereby stipu-
lates and agrees that no change, extension of time, alteration or addition to the
terms of the contract or to the WORK to be performed thereunder of the
SPECIFICATIONS accompanying the same shall in anywise affect its obligation
on this BOND, and it does hereby waive notice of any such change, extension of
time, alteration or addition to the terms of the contract or to the WORK or to the
SPECIFICATIONS.
PROVIDED, FURTHER, that no final settlement between the OWNER and the
CONTRACTOR shall abridge the right of any beneficiary hereunder, whose claim
may be unsatisfied.
IN WITNESS WHEREOF, this instrument is executed in counter-
parts, each one of which shall be deemed an original, this the
day of , 19 .

ATTEST:
(Principal) Secretary
(SEAL)
Principal
By (s)
(Witness as to Principal) (Address)
(Address)
ATTEST:
(Surety) Secretary
(SEAL)
Witness as to Surety Attorney-in-Fact
(Address) (Address)

NOTE: Date of BOND must not be prior to date of Contract. If CONTRACTOR
is Partnership, all partners should execute BOND.
IMPORTANT: Surety companies executing BONDS must appear on the
Treasury Department's most current list (Circular 570 as amended) and be
authorized to transact business in the State where the PROJECT is located.
F-6
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PERFORMANCE BOND
KNOW ALL MEN BY THESE PRESENT: that
(Name of Contractor)
(Address of Contractor)
(Corporation, Partnership, or Individual)
, hereinafter called Principal, and
(Name of Surety)
(Address of Surety)

hereinafter called Surety, are held and firmly bound unto
(Name of Owner)
(Address of Owner)

THE CONDITION OF THIS OBLIGATION is such that whereas, the Principal
entered into a certain contract with the OWNER, dated the
day of 19 t a
copy of which is hereto attached and made a part hereof for the construction of:
NOW, THEREFORE, if the Principal shall promptly make payment to all per-
sons, firms, SUBCONTRACTORS, and corporations furnishing materials for or
performing labor in the prosecution of the WORK provided for in such contract,
and any authorized extension or modification thereof, including all amounts due
for materials, lubricants, oil, gasoline, coal and coke, repairs on machinery,
equipment and tools, consumed or used in connection with the construction of
such WORK, and all insurance premiums on said WORK, and for all labor per-
formed in such WORK whether by SUBCONTRACTOR or otherwise, then this
obligation shall be void; otherwise to remain in full force and effect.
F-7
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