United States
Environmental Protection
Agency
Region 4
345 Courtland Street, NE
Atlanta, GA 30365
EPA 904/9-83-107
March 1983
<>EPA
Environmental
Impact Statement
Phase 1 Report
FRESHWATER WETLANDS
FOR
WASTEWATER MANAGEMENT
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U. S. ENVIRONMENTAL PROTECTION AGENCY
REGION IV - ATLANTA
FRESHWATER WETLANDS FOR WASTEWATER MANAGEMENT
ENVIRONMENTAL IMPACT STATEMENT
PHASE I REPORT
February 1983
U.S. Environnrental Protection
Region 5, Library f5PL-16>
230 S. Dearborn Sti-eet, Roon 1670
Chicago, IL 60604
Claude Terry & Associates, Inc.
Gannett Fleming Corddry and Carpenter, Inc.
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LIST OF PREPARERS
This Phase I Report was prepared under the supervision of Mr. Ron
Mikulak, Project Officer with the United States Environmental Protection
Agency in Atlanta, Georgia.
The Report was prepared by two firms: 1) Claude Terry & Associates, Inc.
in Atlanta, Georgia, and 2) Gannett Fleming Corddry and Carpenter, Inc. in
Harrisburg, Pennsylvania.
U. S. Environmental Protection Agency
Robert B. Howard
Ronald J. Mikulak
John Marlar
Lee Tebo
Al Lucas
Chief, NEPA Compliance Section
Project Officer
Chief, Facilities Performance Branch
Chief, Ecological Support Branch
Environmental Review Section
Claude E. Terry
R. Gregory Bourne
Craig H. Wolfgang
Michael Brewer
James Butner
Louise Franklin
Claude Terry & Associates, Inc.
Prime Contractor
Project Executive
Project Manager
Environmental Planner
Environmental Scientist
Environmental Scientist
Environmental Planner
Gannett Fleming Corddry and Carpenter, Inc.
Subcontractor
Thomas M. Rachford
David B. Babcock
John Jacobs
Sara Frailey
Senior Project Director
Project Director
Soils Scientist
Environmental Engineer
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FRESHWATER WETLANDS EIS - PHASE I
REPORT OUTLINE
1.0 INTRODUCTION 1
1.1 Purpose of Study 4
1.2 Issues of Concern 6
1.3 Phase I 8
1.4 Wetlands Research 10
2.0 WETLANDS DEFINITIONS AND INVENTORY 13
2.1 Wetland Definitions 14
2.2 Wetland Classification Systems 16
2.2.1 Fish & Wildlife Service Classification System 17
2.2.1.1 Circular #39 18
2.2.1.2 National Wetland Inventory Classification 22
System
2.2.2 Corps of Engineers 31
2.2.3 Other Federal Agencies 34
2.2.4 Wetland Classification by Penfound 35
2.2.5 Goodwin and Niering's Classification of Significant 37
Natural Wetlands
2.2.6 Miscellaneous Classification Systems 39
2.3 State Wetland Inventories 42
2.3.1 Alabama 44
2.3.2 Florida 48
2.3.3 Georgia 51
2.3.4 Kentucky 54
2.3.5 Mississippi 57
2.3.6 North Carolina 60
2.3.7 South Carolina 63
2.3.8 Tennessee . 66
2.4 Classification System Used for this EIS 69
3.0 PROFILE OF EXISTING WETLANDS DISCHARGES 73
3.1 Alabama 77
3.2 Florida 80
3.3 Georgia 87
3.4 Kentucky 90
3.5 Mississippi 91
3.6 North Carolina 95
3.7 South Carolina 99
3.8 Tennessee 104
4.0 NATURAL WETLAND CHARACTERISTICS 107
4.1 Geomorphology 109
4.1.1 Geology 116
4.1.2 Soils 119
4.2 Vegetation 121
4.2.1 Plant Ecology 122
4.2.2 Vegetation Types 125
4.2.3 Succession 127
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4.2.4 Productivity 131
4.2.5 Rare, Endangered Ecotypes 134
4.3 Hydrology 137
4.3.1 Hydrologic Budgeting 138
4.3.2 Inundation: Frequency and Duration 142
4.3.2.1 Relationship Between Flooding, 144
Plants and Nutrients
146
147
149
150
4.4 Water Quality 151
153
155
157
160
162
166
169
171
174
4.5 Wildlife 175
176
178
181
183
185
187
189
191
193
195
5.0 INSTITUTIONAL CONSIDERATIONS 197
5.1 Federal Policies and Regulations 199
5.1.1 U. S. Environmental Protection Agency 200
5.1.2 U. S. Corps of Engineers 201
5.1.3 U. S. Fish and Wildlife Service 202
5.1.4 Proposed Amendments to the Water 203
Quality Standards Regulations
5.2 State Policies & Regulations 206
5.2.1 Alabama 208
5.2.2 Florida 210
5.2.3 Georgia 213
5.2.4 Kentucky 215
5.2.5 Mississippi 217
5.2.6 North Carolina 219
5.2.7 South Carolina 221
5.2.8 Tennessee 223
5.3 Wetlands Discharge: Treatment or Disposal 225
5.4 Existing Implementation Problems 227
4.3.3
4.3.4
4.3.5
Water
4.4.1
4.4.2
4.4.3
4.4.4
4.4.5
Wildli
4.5.1
4.5.2
4.3.2.2 Filtration
Buffering
Storage
Groundwater Recharge
Quality
Dissolved Oxygen
pH
Metals
Nutrients
4.4.4.1 Nitrogen
4.4.4.2 Phosphorus
4.4.4.3 Carbon
4.4.4.4 Sulfur
Bacteria
fe
Value of Wetlands as Habitat for Wildlife
Threatened and Endangered Species
4.5.2.1 Alabama
4.5.2.2 Florida
4.5.2.3 Georgia
4.5.2.4 Kentucky
4.5.2.5 Mississippi
4.5.2.6 North Carolina
4.5.2.7 South Carolina
4.5.2.8 Tennessee
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6.0 ENGINEERING CONSIDERATIONS 231
6.1 Facilities Planning and Preliminary Design 233
6.1.1 Proposed Use of Wetlands 235
6.1.2 Site Selection 237
6.1.3 Alternative Physical Configurations 239
6.1.4 Pre-Treatment Requirements 241
6.1.5 Allowable Wastewater Loadings to Wetlands 242
6.1.6 Other Preliminary Design Considerations 251
6.1.7 Costs and Economic Values 254
6.1.8 Areas of Uncertainties 258
6.2 Design of Natural and Artificial Wetland Wastewater Systems 260
6.2.1 Design Criteria 261
6.2.2 Wetland Mixing Patterns and Methods of Effluent 267
Application
6.2.3 Site Access and Easements 270
6.2.4 Safety Factors to Account for Uncertainties 271
6.2.5 Drafting and Specifications 272
6.3 Installation 273
6.3.1 Techniques 274
6.3.2 Construction Inspection 276
6.3.3 Operational Initiation 278
6.4 Operation and Maintenance 280
6.4.1 Maintenance of Effluent Distribution within 281
Wetland Areas
6.4.2 Resting Periods and Use of Storage Facilities 284
6.4.3 Energy, Chemical and Equipment Needs 285
6.4.4 Consequencies of Improper Operation and Maintenance 286
7.0 MANAGED WETLAND CONSIDERATIONS 287
7.1 Impacts to Natural Characteristics 289
7.1.1 Hydrology 291
7.1.2 Vegetation 292
7.1.3 Nutrients 296
7.1.4 Wildlife 300
7.1.5 Public Health 302
7.1.6 Natural and Artificial Wetlands 304
7.2 Monitoring
7.2.1 Water Resources 306
7.2.2 Water Quality - Aquatic Ecology 308
7.3 Analytical Tools
7.3.1 Wetland Ecosystem Modeling 310
7.3.2 State Modeling Efforts 312
8.0 RANGE OF KEY FACTORS 315
8.1 Key Engineering Considerations 316
8.1.1 Hydrologic Parameters 319
8.1.2 Water Quality Parameters 323
8.2 Key Environmental Management Parameters
8.2.1 Habitat and Wildlife 334
8.3.3 Public Health 335
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9.0 SUMMARY 337
9.1 Critical Technical Considerations 338
9.1.1 General Elements Critical to Evaluating Wetlands 339
Discharges
9.1.2 Site Specific Elements Critical to Evaluating 344
Wetlands Discharges
9.2 Critical Institutional Considerations 350
9.2.1 Wetlands Protection/Use 351
9.2.2 Ownership and Proprietary Rights 353
9.2.3 NPDES Permit Process 354
10.0 RECOMMENDATIONS FOR PHASE II 357
11.0 APPENDIX 361
12.0 BIBLIOGRAPHY 365
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LIST OF TABLES
Table
Page
2.2.1.1-a Description of Wetland Types in the United 19
States as Defined in Circular #39.
2.2.1.1-b Circular #39 Wetland Types Addressed by this EIS. 20
2-2.1.2 Comparison of Wetland Types Described in U. S. Fish 24
and Wildlife Service Circular #39 with Some of
the Major Components of NWI System.
2.2.2 The COE Wetland Classification System and Identify- 32
ing Features Appropriate to Freshwater Wetlands.
2.2.4 Major Freshwater Southeastern Wetland Types As 36
Classified by Penfound (1952).
2.2.6-a Kuchler's Wetland Vegetation Types. 40
2.2.6-b Forested Wetlands of Florida. 41
2.3.1 Wetland Inventories in Alabama. 45
2.3.2 Wetland Inventories in Florida. 49
2.3.3 Wetland Inventories in Georgia. 52
2.3.4 Wetland Inventories in Kentucky. 55
2.3.5 Wetland Inventories in Mississippi. 58
2.3.6 Wetland Inventories in North Carolina. 61
2.3.7 Wetland Inventories in South Carolina. 64
2.3.8 Wetland Inventories in Tennessee. 67
2.4 Wetlands EIS Classification Matrix. 71
3.0-a Information form sent to existing wetland 74
Dischargers in Region IV.
3-°-b Total Number of Surveyed Wetlands Discharges by 76
State and the Number of Respondents.
3-1 The Profile of Wetland Discharges Based on Ques- 79
tionnaire Response for Alabama.
3*2 The Profile of Wetland Discharges Based on Ques- 83
tionnaire Response for Florida.
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LIST OF TABLES
Table Page
3.3 The Profile of Wetland Discharges Based on Ques- 89
tionnaire Response for Georgia.
3.5 The Profile of Wetland Discharges Based on Ques- 93
tionnaire Response for Mississippi.
3.6 The Profile of Wetland Discharges Based on Ques- 97
tionnaire Response for North Carolina.
3.7 The Profile of Wetland Discharges Based on Ques- 101
tionnaire Response for South Carolina.
3.8 The Profile of Wetland Discharges Based on Ques- 106
tionnaire Response for Tennessee.
4.2.3 General Attributes of Successional Trends. 128
4.2.5-a Landmark Wetlands of Region IV. 135
4.2.5-b Minor Marsh and Swamp Types Discussed by Penfound
(1952). 136
4.4.4.2 Inputs of Total Phosphorus to Four Types of Cypress 168
Ecosystems.
4.5.2 United States Department of Interior Fish and Wildlife 180
Service List of Wetland-dependent Endangered (E) and
Threatened (T) Species Endemic to Region IV.
4.5.2.1 List of Wetland-dependent Species in Alabama of 182
Endangered (E), Threatened (T) and Special Concern
Status (S).
4-5.2.2 List of Wetland-dependent Species in Florida of 184
Endangered (E), Threatened (T) and Special Concern
Status (S).
4.5.2.3 List of Wetland-dependent Species in Georgia of 186
Endangered Status (E), Threatened Status (T), Rare
Status (R) or Unusual Status.
4.5.2.4 List of Wetland-dependent Species in Kentucky of 188
the Endangered Status (E), Threatened Status (T) or
Rare Status (R).
4.5.2.5 List of Wetland-dependent Species in Mississippi of 190
Endangered Status (E), or Threatened (T) Status.
4.5.2.6 List of Wetland-dependent Species in North Carolina of 192
Endangered Status (E), or Threatened (T) Status.
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LIST OF TABLES
Table Page
4.5.2.7 List of Wetland-dependent Species in South Carolina of 194
Endangered Status (E), or Threatened (T) Status.
4.5.2.8 List of Wetland-dependent Species in Tennessee of 196
Endangered Status (E), and Threatened (T) Status.
6.1 Artificial Wetlands Used for the Treatment of 234
Wastewater.
6.1.5-a Removal (Conversion) Mechanisms in Wetlands for the 245
Contaminants in Wastewater.
6.1.5-b Engineering Characteristics and Treatment Efficiencies 246
for Various Aquaculture Wetland-Wastewater Systems in
the Southeastern United States.
6.1.5-c Engineering Characteristics and Treatment Efficiencies 248
for Various Natural Wetland-Wastewater Systems in the
Southeastern United States.
6.1.5-d Performance of Polyculture Systems Utilizing Fish. 250
6.1.7 Annual and Unit Costs, Excluding Land for Treatment 256
Systems.
6-2. 1-a Preliminary Design Parameters for Planning Artificial 262
Wetland Wastewater Treatment Systems.
6.2.1-b Design Criteria for Water Hyacinth Wastewater 265
Treatment Systems to be Operated in Warmer Climates.
6.2.1-c Recommendations for the Construction of Hyacinth 266
Basins for Upgrading Stabilization Pond Effluent.
6.2.2 Effluent Application Configurations. 268
7.1 hetldriii tcosystem Kesponse to Various Hydrologic 290
Factors.
7.1.6 Reported Removal Efficiency Ranges for the Constituents 305
in Wastewater in Natural and Artificial Systems.
8.1 Relationship of Hydrologic Factors to Pollutant 317
Removal in Wetlands.
8.1.1 Hydrologic Loading in Artificial and Natural Wetland 321
Systems.
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LIST OF TABLES
Table Page
8.1.2-a Nutrient Loading in Artificial and Natural Wetland 324
Systems.
8.1.2-b Summary of Nutrient Loading Rates Applied to Water 325
Hyacinths Wastewater Treatment Systems.
8.1.2-c Typical Concentrations of Metals in Aquatic Plants 326
Grown in Metals Contaminated Environments.
8.1.2-d Influent and Effluent Concentrations of Metals from a 326
Cattail Marsh Receiving Comminuted Wastewater with
15 Days Residence Time.
8.1.2-e Known Acceptable Values or Ranges for Various Key 327
Factors for Aquaculture Systems.
9'1*1 Areas of Key Concern of Wetland Characteristics. 340
9.1.2 Areas of High Importance in Selected Region IV Wetlands. 346
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LIST OF FIGURES
Page
!'3 Levels of analysis incorporated into Phase I of EIS. 9
2.2.1.2-a NWI wetlands classification system. 26
2.2.1.2-b Ecoregions of the Southeastern United States. 27
2.2.1.2-c NWI palustrine wetland types. 28
2.2.1.2-d NWI lacustrine and palustrine wetland types. 29
2.2.1.2-e NWI palustrine and riverine wetland types. 30
2-2«2 Boundaries for COE regional wetland guides found within 33
Region IV.
2.3.1 Status of the National Wetlands Inventory in Alabama. 47
2.3.2 Status of the National Wetlands Inventory in Florida. 50
2.3.3 Status of the National Wetlands Inventory in Georgia. 53
2.3.4 Status of the National Wetlands Inventory in Kentucky. 56
2-3-5 Status of the National Wetlands Inventory in Mississippi. 59
2.3.6 Status of the National Wetlands Inventory in North 62
Carolina.
2'3-7 Status of the National Wetlands Inventory in South 65
Carolina.
2-3-8 Status of the National Wetlands Inventory in Tennessee. 68
4.1-a Physical profile of cypress dome receiving sewage 110
effluent.
4.1-b Profile of submergent wetland marsh community. Ill
4.1-c Transition from riparian wetlands to bottomland 112
hardwoods.
4.1-d Profile of transition between several common wetland 113
types.
4-1-e Profiled, various components of the bottomland 114
hardwoods ecosystems.
4-1-f Stratigraphic profile of soil beneath a pocosin wetland. 115
4.1.1 Representataive cross-section of karstic geology. 118
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LIST OF FIGURES
Figure Page
4.2.3 Relationship between hyd rope Mod, fire and succession for 129
selected Florida ecosystems.
4.2.4 Hypothesized relationship between fire and net 133
productivity for several wetland forests.
4.3.1 Systems diagram of the dominant components of a 139
hydrologic budget.
4.3.2.1 The relationship between wetland ecosystems, water input 145
and nutrient regime.
4.3.3 Graphic presentation of a floodplain's ability to 148
attenuate discharge rate and peak flows with and without
wetlands.
4.4.3 Relationship of heavy metal ion form and solubility in 159
the aquatic environments.
4.4.4 Carbon, nitrogen and sulfur transformations in 161
oxygen-poor (anaerobic) environments.
4.4.4.1-a Generalized nitrogen and phosphorus cycling in aquatic 164
environments.
4.4.4.1-b Major components of the nitrogen cycle in aquatic 165
environments.
4.4.4.4 Generalized sulfur cycling in the environment. 173
7.1.2 Potential modifications resulting from wetland 295
management.
7.1.3 Representation of nutrient storages and flows in wetland 299
ecosystem receiving wastewater ("cultural water").
8.1.2-a Effect of phosphorus loading on phosphorus removal. 330
8.1.2-b Effluent BOD concentrations (aquaculture systems). 331
8.1.2-c Effect of BOD loading on BOD removal. 332
8.1.2-d Effect of BOD loading on BOD removal (marsh and peatland 333
systems).
10.0 Major components of decision tree for wastewater disposal 358
to wetlands.
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SECTION 1
INTRODUCTION
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1.0 INTRODUCTION
EIS RESPONDS TO ISSUES ENCOUNTERED WITH EXISTING WETLANDS DISCHARGES
The understanding of wetlands values and functions has
Increased significantly during the past decade. During
that period more attention has also been given to the use
of wetlands for wastewater management. With increased
pressure placed on wetland systems in recent years,
regulatory and ecological issues have been raised. This
EIS is designed to develop tools that can assist local,
state and federal agencies in making wastewater management
decisions affecting wetlands.
Since the late 1800's, natural wetland systems have been used for
wastewater management in the Southeastern United States. In recent years,
more communities have begun using wetlands for this purpose despite the
increased attention given wetlands as their functions and values have become
more fully understood. Research on wetlands has increased significantly
during the past ten years, including research on wetlands used for wastewater
management. Many systems used for wastewater management have been studied in
Florida, and throughout the United States. But many questions regarding the
use and management of natural wetland systems remain. This EIS has been
initiated to address many of these questions, as more than 400 communities in
the eight EPA Region IV states currently use wetlands for wastewater
management.
EPA's involvement in wastewater management in freshwater wetlands is
related to two specific program areas: Sections 201 and 402 of the Clean
Water Act. Section 201 of the Act authorizes the Agency to participate in
providing grant funds for the planning, design and construction of wastewater
facilities. Section 402 of the Act authorizes the Agency to issue National
Pollutant Discharge Elimination System (NPDES) permits to facilities that
discharge treated wastewater to surface waters of the United States.
In the 201 program, the initial planning step involves the identification
of a community's wastewater management needs and public health problems, and
an investigation of available and reasonable wastewater management
alternatives. The development and evaluation of wastewater management
alternatives has become a critically important component of this planning
step and EPA has provided considerable guidance to potential grant applicants
in this area. Regional program offices have, however, identified a lack of
guidance in the area of wastewater management in freshwater wetland areas.
The pressures to continue and increase the use of wetlands for wastewater
management are not likely to diminish in the near future. The cost of more
conventional management alternatives is rising, treatment levels are becoming
more stringent and surface water discharge opportunities are becoming more
limited. This EIS is designed to be a supplement to the alternatives
development and evaluation phases of the facilities planning process and will
provide information and guidance concerning the means for considering
wetlands as part of a wastewater management system.
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1.0 Continued
Section 402 of the Clean Water Act established the National Pollutant
Discharge Elimination System (NPDES) to provide a permitting system for
all point source pollution discharges into waters of the United States.
The issuance of NPDES Permits involves determining appropriate effluent
limitations either to meet water quality standards or to meet minimal
prescribed treatment levels (whichever is more stringent). For typical
surface water discharges, this process is addressed in a fairly standard
and straight forward fashion. In the case of wastewater discharges to
freshwater wetlands, however, the permitting process and procedures are
less clearly defined. This EIS should provide the institutional guidance
and technical tools needed by applicants, consultants, states and federal
regulatory agencies in the process of evaluating freshwater wetlands for
wastewater management.
In addressing thses program needs, this EIS is designed to be a
comprehensive study that fully recognizes and assesses the issues
affecting the use of wetlands for wastewater management. Further, the EIS
is intended to help coordinate the various issues that impact the 201 and
NPDES Permit decision-making processes currently followed in Region IV
states. The study will address all freshwater wetlands in Region IV with
the exception of the Everglades and the South Florida wetlands that are
unique to that area. Saltwater wetlands have also been excluded from this
EIS but will be the subject of a separate study.
The EIS has been divided into two separate and distinct phases. Phase
I is intended to collect the background information necessary to identify
the major regulatory and ecological issues encountered in Region IV.
Phase II tasks will lead to the development of procedures and tools for
decision making that fully account for the key regulatory and ecological
issues identified in Phase I. Stated another way, Phase I will involve
inventory and data collection tasks: Phase II will involve the
development and evaluation of decision-making tools. Both phases will
address the variations that occur between states in data bases and
policies.
The Phase I Report is preliminary to the major output of the EIS,
which will be the delineation of tools and procedures for assessing the
use of wetlands for wastewater management. These tools and procedures
will be discussed fully in the Phase II Report and associated handbook.
The handbook will be designed for persons involved with decision
making, such as local and state government officials, as well as
engineering consultants and others who may be involved in the design or
implementation of wetlandswastewater systems. Methods of analysis,
safeguards and guidelines for evaluating, selecting, permitting and
monitoring wetlands systems acceptable for wastewater management will be
detailed.
This report is a comprehensive synopsis of institutional, scientific
and engineering considerations associated with wetlands wastewater
management systems in the Southeast. The literature on these topics is
exhaustive. The literature also addresses a wide variety of auxilliary
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1.0 Continued
topics, some of which have minimal importance in the discussion of south-
eastern wetlands. This report should not be considered a complete treatise
on wetlands. Rather, the report summarizes the most important considerations
that relate to the use of wetlands for wastewater management. A team of
highly qualified wetlands researchers has assisted in reviewing the
scientific and engineering aspects of the report.
Issues of Interest
What are the scientific, institutional and engineering factors that are
important for wastewater management in wetlands?
Are scientific, engineering, and institutional issues equally important?
What are the key factors in wetlands wastewater management for which
further investigation, analytical tools or guidelines are needed?
What mechanisms are available to avoid or mitigate detrimental impacts of
wastewater discharges to wetlands?
What is currently known about wastewater discharges to wetlands?
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1.0 INTRODUCTION
1.1 Purpose of Study
EIS DESIGNED TO ASSESS FEASIBILITY OF USING WETLANDS
FOR WASTEWATER MANAGEMENT
Wetlands have been used for wastewater management within
Region IV for many years. In recent years the value of
wetland ecosystems has been realized and several
protection mechanisms have been established. Wetland
discharges are now evaluated in light of these mechanisms.
Over the past several years, wetlands have received increased atten-
tion as valuable and sensitive ecosystems. Prior to that time, wetlands
were commonly drained and/or filled, based on the perception that they had
little importance. Even today many states, including some in Region IV,
exert little influence over the development and destruction of valuable
wetland resources. Intensive development within the southeastern United
States has applied continuing pressure to these systems.
Unless purchased by the federal or state government, freshwater wet-
lands are virtually unprotected. The Corps of Engineers has authority
under Section 404 of the Clean Water Act to permit requests to dredge or
fill wetlands. Yet many small wetlands systems do not receive protection
under this jurisdiction. In 1977 former President Carter issued an Execu-
tive Order instructing that federal funding not be provided for develop-
ment activities in wetlands (or floodplains).
Wetlands disposal of treated wastewater is not a new concept. Wet-
lands have been used in this country and abroad for wastewater disposal
for many years, in some cases dating back to the 1890's. It has only been
recently, however, that wetlands have been studied for their capacity to
accept and renovate wastewater. To a certain extent this corresponds to
increased understanding of how wetlands function and the important role
they have as ecosystems. A better understanding of how wetlands function
now indicates that they provide a good natural mechanism for wastewater
disposal and renovation under some circumstances.
The proposed use of freshwater wetlands for wastewater disposal must
be viewed from two perspectives. In some respects, parallels exist
between the issues of wetland development and wetland disposal. Yet the
two are distinct in many ways, particularly regarding the types of impacts
to wetlands. With development, the hydrologic regime of wetlands is
typically altered or destroyed along with the vegetation of the system.
With disposal of wastewater, the impacts are more subtle, and the wetland
continues to function if the disposal is properly managed. But what
changes are acceptable and how much change can occur before the result is
alteration or degradation? These are some of the issues that will be
addressed by this EIS.
This EIS is intended to explore the feasibility of utilizing fresh-
water wetlands for wastewater management throughout the eight states of
EPA Region IV: Alabama, Florida, Georgia, Kentucky, Mississippi, North
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1.1 Continued
Carolina, South Carolina and Tennessee. The various and unique wetlands
systems present throughout Region IV must first be examined. Their location,
extensiveness, function, and capability to renovate wastewater will be
subsequently evaluated.
The analysis is approached from two entirely different perspectives: 1)
institutional considerations as they relate to federal, state and local
regulations and policies; and 2) technical considerations as they relate to
scientific and engineering knowledge of wetlands and existing wetlands
disposal systems.
The remaining objectives of the EIS deal primarily with conducting an
inventory of existing wetlands discharges and identifying limitations in
present understandings of wetlands systems and their response to
perturbations.
This EIS is designed to respond to such questions as "Is wetlands
disposal feasible for a community?", and "Can the important functions of a
wetlands system be maintained if used in this manner?"
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1.0 INTRODUCTION
1.2 Issues of Concern
INSTITUTIONAL, SCIENTIFIC AND ENGINEERING ISSUES
MUST BE CONSIDERED
Wetlands are complex ecosystems with many components. As
managed systems, they must be evaluated for capabilities
to renovate wastewater. Maintenance of natural functions
must also be assured to achieve continued renovation and
protect other values of wetlands ecosystems.
Wetlands embody several unique functions and are valuable ecosystems.
They serve an important role in the provision of habitat, in nutrient cycling
and in the flow regimes of both surface and groundwaters. As wetlands have
been managed for wastewater management or aquaculture, many regulatory and
legal issues have been raised. The dredging and filling of wetlands has also
drawn increased attention to the ecological role of wetlands and their pro-
tection. As questions concerning the role of wetlands as managed natural
systems have been posed, limitations in the existing information base and our
subsequent understanding about wetlands have surfaced.
Two review committees have been formed to help identify issues of concern
and to assist in the direction and review of this EIS. An institutional
committee has been formed, composed of a representative from each of the
eight Region IV states, the U.S. Fish and Wildlife Service and the U.S. Corps
of Engineers. A technical committee has also been established, comprised of
individuals who have direct research experience and practical experience with
wetlands systems. Universities and federal agencies are also represented.
Several other issues of special concern were identified by the Directive of
Work for this EIS. These include:
Institutional
Policies or regulations on wetlands disposal at federal, state, or local
levels
Differentiation of wetland types, indicating those most appropriate for
wetlands discharges
Methods for determining wasteload allocations
Impacts of revised water quality standards regulations
Treatment vs disposal issue
Scientific
Assessment of wetland values and functions
Presence of threatened or endangered species in wetlands
Presence of wildlife with recreational and aesthetic values
Impacts of various qualities and volumes of effluent on floral and faunal
communities
Hydrologic consequences of wetlands disposal
Evaluation of existing data base and needs for data collection/monitoring
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1.2 Continued
Engineering
- Specific effluent characteristics which would preclude wetlands disposal
- Potential beneficial results of wetlands disposal, particularly to
artifically depleted wetlands
- Impacts to recreational or commercial resources
- Public health impacts
- Development of preferred planning, design, implementation and opera-
tion-maintenance techniques
Each of the areas of concern presented above will be addressed by this
report, in an effort to acknowledge and respond to all issues that affect the
feasibility of wastewater disposal to freshwater wetlands.
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1.0 INTRODUCTION
1.3 Phase I
EIS IS BEING CONDUCTED IN A MULTI-PHASED APPROACH
The wetlands EIS will be conducted in multiple phases.
This report reviews the findings of Phase I. Additional
phases will establish guidelines for assessing wetlands
management options and will evaluate the thoroughness and
effectiveness of those guidelines.
Several major objectives of the EIS are identified in Sections 1.1 and
1.2. In defining the scope of work, EPA recognizes two distinct aspects of
the study. The major goal of the study is to provide institutional and tech-
nical procedures by which existing and potential wetlands discharges could be
evaluated. This is not necessarily an endorsement of wetlands discharges but
rather an acknowledgement that they currently exist and should be properly
evaluated and permitted.
It is necessary to compile pertinent information on existing discharges
and the state-of-understanding of wastewater impacts on wetlands before a set
of procedures can be established. Further, an inventory of all wetland
types, wetland characteristics, and wetland functions is necessary.
Due to the importance of this information and the necessity of collecting
it prior to establishing procedures, a multi-phased approach to the study has
been adopted. Phase I deals with the collection and analysis of information
concerning wetlands and wastewater discharges to wetlands. In addition,
scientific, engineering, and institutional considerations are addressed by
Phase I.
Based upon the results of Phase I, the Phase II Plan of Study will be
prepared. Phase II will be designed to establish institutional and technical
procedures for evaluating a potential wetlands discharge. Also included will
be the delineation of monitoring requirements, back-up systems, treatment re-
quirements, and acceptable wetlands systems (if any) for a potential
discharge. Case studies will be conducted as part of Phase II; however, the
degree and level of any field studies are not yet determined.
The remainder of this report details the findings of Phase I tasks that
are indicated by the outline. STOP-format is used to help the reader quickly
identify major components of the report and particular sections of interest.
This format highlights the contents of each major section by using headlines
and abstracts.
Several distinct topics, representing distinct tasks, were analyzed under
Phase I. However, all the analyses were combined to form the Phase I report
to indicate the comprehensive yet integrated nature of the study and present
the information more cohesively than would a series of individual task
reports.
Figure 1.3 displays the areas of analyses that comprise Phase I.
-------
Definitions
and Classification
of Wetlands
Profile of
Existing
Wetlands
Discharges
Analysis of
Key Scientific
Components
Evaluation of
Institutional
Issues
Analysis of
Engineering
Practices
Figure 1.3. Levels of analysis Incorporated into Phase I of EIS.
Source: Claude Terry & Associates, Inc. 1982.
Recommendations
for Future
Analyses
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1.0 INTRODUCTION
1.4 Wetlands Research
RESEARCH PROJECTS ON MANAGED WETLANDS HAVE INCREASED IN RECENT YEARS
During the past 10 years, Interest In wetlands research
has expanded. Numerous research projects have been
conducted. Several symposia have been held to review
current research and assess the state-of-the-art.
Over the past decade, wetlands have received increased attention as indi-
cated by the level of funding committed to research. Numerous symposia have
been held on both natural and managed wetlands systems. The research con-
ducted and conferences held on the state-of-understanding have assisted in
defining critical functions, issues and data limitations that should be
considered.
Major research efforts on wetlands systems have been conducted at numer-
ous universities throughout the United States and abroad. Several univer-
sities have conducted long-term studies on managed wetland systems that have
received wastewater effluent. These include:
- University of Florida, Center for Wetlands
- University of Michigan
- Louisiana State University, Center for Wetland Resources
- University of California (Davis), Dept. of Land, Air, and Water Resources.
Several federal agencies have also been involved with wetland studies,
including:
- The U.S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, MS
- The U.S. Fish and Wildlife Service, National Wetlands Inventory, St.
Petersburg, FL
- The U.S. Environmental Protection Agency, Region V, Chicago, IL
- The National Aeronautics and Space Administration, NSTL Station, MS
- The U.S. Environmental Protection Agency, Corvallis Environmental
Research Agency, Corvallis, OR.
The U.S. Fish and Wildlife Service has also compiled an annotated bibli-
ography of over 800 references concerning the various aspects of wetlands
systems as they pertain to wetlands management.
In a series of studies conducted by universities, federal agencies, and a
few engineering firms, several wetlands systems used for wastewater dis-
charges in the Southeast have been examined. These systems are located pri-
marily in Florida where much of the wetlands research in Region IV has
occurred. Systems are located in or near the communities of:
- Clermont, Florida
Gainesville, Florida
- Jacksonville, Florida
- Jasper, Florida
- Lake Buena Vista, Florida
10
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1.4 Continued
- Madison, Florida
- Waldo, Florida
- Wildwood, Florida.
Finally, a number of symposia or conferences on wetlands have been held
since 1975. These have been useful for information transfer. The primary
conferences pertinent to this project include:
- Wetlands Treatment of Municipal Wastewater, June 23-25, 1982, University
of Massachusetts, Amherst, Massachusetts
- National Wetlands Technical Council: Bottomland Hardwood Wetlands, June
1-5, 1980, Lake Lanier, Georgia
- Aquaculture Systems for Wastewater Treatment, September 11-12, 1979
University of California, Davis, California
- Water Reuse Symposium, March 25-30, 1979 Washington, D.C.
- National Wetland Protection Symposium, 1979 U.S. Fish and Wildlife
Service, Washington, D.C.
- National Symposium on Wetlands, November 7-10, 1978 Disney World Village,
Lake Buena Vista, Florida
- Wetlands Utilization Conference, Kissimmee River Coordinating Council,
Ongoing Annual Meetings since 1978
- Society of Wetland Scientists, Ongoing Annual Meetings since 1980,
various locations
- Freshwater Marshes: Present Status, Future Needs, February, 1977,
Rutgers University, New Brunswick, New Jersey.
- National Symposium on Freshwater Wetlands and Sewage Effluent Disposal,
May 1976, University of Michigan, Ann Arbor, Michigan.
This does not represent an all-inclusive listing of wetlands symposia and
research efforts. It does represent those activities that have provided
major contributions to the understanding of wetlands systems and their role
in wastewater management throughout the southeastern United States.
11
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SECTION 2
WETLANDS DEFINITIONS AND INVENTORIES
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2.0 WETLANDS DEFINITIONS AND INVENTORY
CLASSIFICATION SYSTEMS HAVE BEEN DEVELOPED TO DEFINE
WETLANDS SYSTEMS
The identification and inventory of wetlands systems 1s
dependent on an adequate system of classification.
Several have been proposed but many have limitations for
fully describing and delineating wetlands systems. Wet-
land inventories have been conducted in Region IV but are
not exhaustive in coverage.
A critical component in studying wetlands is delineating their extent and
location. In Region IV, there are numerous types of wetlands due to the tern
perature and topographic gradients across the'Srea? Depend t upo ^ these and
Wetlands are commonly differentiated and delineated based on major vege-
tation types. Several classification schemes have been developed by federal
agencies and researchers. Among the federal agencies, the Corps of Engineers
hen vean?v/t±anThW11dllfe SerV1'C? (FWS) have d^eloped the most compre-
Sstems The s>stem recently developed by the FWS is gradually being
*"" 1S ^ m°St comPrehen^ of the sysiems 9
Each of the eight Region IV states has conducted wetlands inventories
However, these have not been exhaustive studies and have used a vaMe[y of
classification schemes and methods. A system will be adopted to help
^^^
wetlands ^flMtfons are
Issues of Interest
• How are wetlands defined by various governmental agencies?
• Why do these definitions vary?
• What wetland classifications systems are used for regulatory purposes?
• Do wetland inventories exist for each state?
• Are existing classification systems suitable for wastewater management?
13
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.1 Wetland Definitions
DEFINITIONS ARE IMPORTANT TO REGULATORY AND CLASSIFICATION EFFORTS
Wetland definitions vary depending on the required detail
and perspective of the involved agency. Definitions
provide a basis for wetland classification systems and a
general agreement of what constitutes a wetland.
Whether or not an area is considered as wetlands usually depends on how
wetlands are defined and classified. The difference between definitions and
classification systems are often based on the definition of different wet-
lands characteristics. The classification systems used for wetlands
delineation and identification are discussed in other sections. The purpose
of this section is to review the various broad concepts describing a wetlands
system.
Clark (1979) has defined a wetland as "a place that is sufficiently satu-
rated with water, often enough, that typical wet soil plants grow there."
This provides a clear concept of the basic characteristics of a wetlands
system.
For regulatory, policy and classification purposes, several government
agencies have proposed general definitions of wetlands. The U.S. Fish and
Wildlife Service, in "Classification of Wetlands and Deepwater Habitats in
the United States" Cowardin et al. (1979), have referred to wetlands in two
different ways:
- Wetlands are lands where saturation with water is the dominant factor
determining the nature of soil development and the types of plants and
animal communities living in the soil and on its surface.
- Wetlands are lands transitional between terrestrial and aquatic systems
where the water table is usually at or near the surface or the land is
covered by shallow water.
These two definitions written from slightly different perspectives highlight
different elements of wetlands characteristics.
Much of the regulatory power over wetlands is held by the U.S. Army Corps
of Engineers in the capacity of permitting dredge and fill activities in wet-
lands. While this jurisdiction does not directly impact the disposal of
wastewater into wetlands, the Corps has established definitions (1977) and
classifications which are widely held. The Corps of Engineers defines wet-
lands as:
- Those areas that are inundated or saturated by surface or groundwater at
a frequency and duration sufficient to support, and that under normal cir-
cumstances do support, a prevalence of vegetation typically adapted for
existence in saturated soil conditions. Wetlands generally incude
swamps, marshes, bogs, and similar areas.
14
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2.1 Continued
Executive Order 11990 issued in 1977 by former President Carter regarding
the protection of wetlands utilizes the Corps of Engineers' definition.
However, it elaborates the Corps of Engineers' definition by expanding the
last sentence to read: similar areas such as sloughs, potholes, wet meadows,
river overflows, mud flats, and natural ponds.
Other definitions have been used for wetlands, but those discussed above
indicate the general characteristics of wetlands as well as can be accom-
plished by a short statement. The definition of different wetland types and
the differentiation between them require a detailed classification system.
Any single definition cannot begin to encompass the variety and complexity of
wetlands. Therefore, while a general definition is helpful to introduce
basic concepts, the actual classification systems used are the mechanisms for
defining wetland systems and their differences.
15
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
CLASSIFICATION SYSTEMS DESIGNED TO FIT NEEDS OF USER
Many wetlands classification systems have been devised
within the scientific and regulatory communities. Most
regulatory agencies rely on vegetation, soils and
hydrologic indicators to typify and classify wetlands. The
scientific community has also relied on these indicators
for classifying wetlands but have also approached
classification from a value/land use perspective.
The FWS employs an extensive and detailed wetland classification system
developed by Cowardin et al. (1979) for the National Wetlands Inventory.
This system provides several different levels of detail in the classification
of a wetland, depending on the needs of the user. This classification system
relies on vegetation, hydrology and soil indicators to characterize wetland
types. The FWS previously used a simple classification system described in a
document referred to as Circular #39. The document delineates wetlands into
20 different types, based on vegetation and hydrology. Because of its wide-
spread use since 1956, a significant amount of state and federal legislation
is tied to its definitions and classifications. At present a clear trend
among regulatory agenices is to switch to the more detailed National Wetlands
Inventory classification system to fulfill their needs and promote inter-
agency consistency. Although the Corps of Engineers (COE) is primarily
interested a jurisdictional definition of a specific wetland area, and not
the type of wetland per se, it has also identified different wetland types in
a series of wetland guides. These guides (COE 1978) are regionally specific
and are designed to assist in the implementation of Section 404 in the
regulation of dredge and fill activities.
Penfound (1952) developed a relatively simple, but straightforward and
informative classification system of wetlands of the southeast. This
benchmark work has provided the basis for many successive classification
schemes for southern wetlands. Penfound's work also has value in highlight-
ing several rare and unusual wetland types. Goodwin and Niering (1975)
employed a modified Circular #39 definition to identify and inventory
significant natural inland wetlands of the U.S.
Other wetland classification systems which have been developed by Golet
and Larson (1974) and Steward and Kantrud (1971) are not especially
applicable to wetlands of the southeast. Lonard et al. (1981) reviewed and
analyzed over 20 methodologies which classified and assessed wetlands on the
basis of various values such as habitat, hydrology, recreation and other
values.
16
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.1 Fish and Wildlife Service Classification System
FISH AND WILDLIFE SERVICE HAS HISTORY OF IfltOLVEMENT WITH DEVELOPMENT
AND UTILIZATION OF WETLAND INVENTORY AND CLASSIFICATION SYSTEMS
Two major classification systems have been employed by
FWS. Both systems utilize vegetative and hydrologic
characteristics to delineate wetland types. The Circular
139 system Is a simpler system, but the more recent
National Wetlands Inventory (NWI) System allows greater
differentiation of wetland types.
The U.S. Fish and Wildlife Service (FWS) has two operational wetland
classification systems. The NWI system (Cowardin et al. 1979) has been
officially adopted by the FWS to be used in all future wetland data base
developments. The wetland classification system presented in Circular #39
(Shaw and Fredline 1956) has been used by FWS for over 20 years and has
significant historical importance. Both of these classification systems
employ aerial photography as the major tool in the location and
classification of wetlands by physiographic province. Existing state
information is utilized by both systems, and the need to maintain a standard
national classification system is emphasized.
The NWI system employs a more extensive and detailed classification
system than does Circular #39 and makes use of the advances in mapping
technology developed in the 20 years since Circular #39 was first issued.
The classification system used for the NWI also reflects the increased level
of understanding of wetland structure and function. It recognizes the
inherent ecological and hydrologic values associated with wetlands. Although
the FWS has officially adopted the NWI system for its wetlands projects, FWS
personnel may continue to use the old classification system where immediate
conversion is not practicable or where applicable laws still reference that
system. Because both systems are still in use and widely referenced, the
next two subsections will discuss these systems in detail.
17
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.1 U.S. Fish and Wildlife Service Classification System
2.2.1.1 Circular #39
CIRCULAR #39 CLASSIFICATION RECEIVES WIDESPREAD USE AND ACCEPTANCE
Circular #39 recognizes 20 types of fresh and saline
wetlands of the U.S. It has been a very influential
document but has been criticized for ignoring important
ecological distinctions among wetlands. Because the
definitions of wetlands in Circular f39 are subject to
wide interpretation and inconsistent application, it has
been replaced as the official FWS classification system.
The primary goals of Circular #39 were to delineate the wildlife value of
wetlands and to provide a perspective for balanced land use planning. The
report was authored by S. P. Shaw and L. Fredine and was originally entitled
Wetlands of the United States—Their Extent and Their Value to Waterfowl and
Other Wildlife." It was the fourth major document on wetlands inventory and
classification commissioned by the U.S. government (others in 1906, 1922,
1940) and marked a significant departure in attitude and purpose from pre-
vious inventories. The emphasis of the earlier wetland documents was to
determine the extent of swamp lands with potential for drainage, reclamation
and conversion to agricultural uses. In contrast, Circular #39 was commis-
sioned in 1956 in response to the rapid rate of conversion of wetlands to
agriculture and other uses and the consequent adverse effects on waterfowl.
Circular #39 has received widespread use and acceptance in the past 20
years. Because of its long term use, a significant amount of state and
federal legislation is directly and indirectly tied to its definitions and
classifications, including the Water Bank Act of 1970 (PL 91-559).
The classification framework that Circular #39 employs places all wet-
lands in one of four major wetland categories: inland fresh, inland saline,
coastal fresh and coastal saline. Within the four major wetland categories,
20 wetland types are identified based on characteristic flooding patterns and
vegetation cover (see Table 2.2.1.1-a). Circular #39 provided total U.S.
acreage estimates for each of the 20 wetland types, and also placed a
qualitative value on wetlands on the basis of their importance as wildlife
habitats. This document fulfilled its primary purpose, but its shortcomings
as a comprehensive and definitive wetland classification and inventory system
have been noted by several authors (Cowardin et al. 1979). The primary
criticism of Circular #39 was that critical ecological differences among
wetlands were ignored. Problems have also been reported in the consistency
of application of Circular #39 definitions, which were subject to a variety
of interpretations.
A description of each wetland type defined by Circular #39 that has
bearing on this EIS is included in Table 2.2.1.1-b.
18
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Table 2.2.1.1-a. Description of Wetland Types in the United States as Defined in Circular #39.
Category Type Water Depth*
Inland Fresh Areas
1. Seasonally flooded basins or flats
2. Inland fresh meadows
3. Inland shallow fresh marshes
4. Inland deep fresh marshes
5. Inland open fresh water
6. Shrub swamps
7. Wooded swamps
8. Bogs
Inland Saline Areas
9. Inland saline flats
10. Inland saline marshes
11. Inland open saline water
Coastal Fresh Areas
12. Coastal shallow fresh marsh
13. Coastal deep fresh marsh
14. Coastal open fresh water
Coastal Saline Areas
15. Coastal salt flats
16. Coastal salt meadows
17. Irregularly flooded salt meadows
18. Regularly flooded salt meadows
19. Sounds and bays
20. Mangrove swamps
Few inches in upland, few feet along rivers
Few inches after heavy rain
Up to 6 inches
Up to 3 feet
Up to 10 feet; marshy border may be present
Up to 6 inches
Up to 1 foot
Shallow ponds may be present
Few inches after heavy rain
Up to 2 feet
Up to 10 feet; marshy border
Up to 6 inches at high tide
Up to 3 feet at high tide
Up to 10 feet, marshy border may be present
May have few inches at high tide
May have few inches at high tide
Few inches at wind tide
Up to 1 foot at hgh tide
Up to 10 feet at high tide
Up to 2 feet
*Refers to average conditions during growing season except for Type 1. In Type 1 bottomlands, flooding
ordinarily occurs in late fall, winter, or spring. In Type 1 upland areas, depressions may be
filled with water during heavy rain or melting snow, predominantly in early spring.
Source: Shaw and Fredine. 1956.
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Table 2.2.1.1-b. Circular #39 Wetland Types Addressed by this EIS.
Circular #39
Wetland Type
Vernacular Name
Description
1
Seasonally flooded basin or
flat
Inland fresh meadows
Inland shallow fresh marshes
Inland deep freshwater
Inland open freshwater
Shrub swamps
Wooded swamps
Site is usually inundated or soils waterlogged on a
seasonal basis. Includes bottomland hardwoods
and some herbaceous growths.
Standing water rare during the growing season
but soils generally waterlogged. Meadows may
fill shallow lake basins or sloughs or border
landward side of shallow marshes.
Soil waterlogged much of the growing season,
often covered with six or more inches of water.
May fill shallow lake basins or sloughs or border
landward side of deep marshes.
Soil covered with six inches to three feet or more
of water during the growing season. May fill shallow
lake basins, potholes, limestone sinks, sloughs, or
border open waters.
Includes shallow ponds and reservoirs.
Water usually less than 10 feet deep
fringed by a border of emergent vegetation.
Waterlogged during growing season, soil
covered with six or more inches of vege-
tation. Occurs often along sluggish streams
and flood plains.
Waterlogged at least to within a few inches
of surface during growing season, often covered
with one foot or more of water. Occurs mostly
along sluggish streams on flood plains, flat
uplands, very shallow lake basins. Often support
herbaceous or aquatic understory and in associa-
tion with shrub-swamps.
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Table 2.2.1.1-b. Continued.
Circular #39
Wetland Type Vernacular Name
Description
8
Bogs
12
Coastal shallow fresh
marsh
13
14
Coastal deep fresh marsh
Coastal open freshwater
Also known as pocosins, bogs, savannahs; soil
waterlogged, supporting spongy layer of mosses.
Occurs in shallow lake basins, sluggish streams
and on flat uplands. Woody or herbaceous vegeta-
tion dominates.
Soils always waterlogged in growing season, up to
up to one foot of water tidal influence, highly pro-
ductive, waterfowl important, vegetation mostly
consists of grasses, sedges, sawgrass, other fresh-
water marsh types.
Average depth greater than above, tidal influence,
vegetation dominates as floating aquatics or
grasses tolerant to deeper water.
Average depth up to six feet, vegetation scarce,
but sometimes mats of hyacinths along Gulf coast areas.
Source: Adapted from Shaw and Fredine. 1956.
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.1 U.S. Fish and Wildlife Service Classification System
2.2.1.2 National Wetland Inventory Classification System
NEW WETLAND CLASSIFICATION SYSTEM DEVISED FOR NATIONAL
WETLAND INVENTORY
The FWS, in cooperation with other federal agencies,
recently developed a classification system for use in the
National Wetlands Inventory. The system encompasses both
deep-water and wetland habitats and classifies them by
their dominant vegetation, soil type and hydrologic condi-
tions. Several levels of classification are available
depending on user needs.
The classification system employed by the National Wetlands Inventory
originated in 1974, when the FWS directed the Office of Biological Services
to design and conduct a new national wetlands inventory to update the 1956
efforts. This directive resulted in the establishment of four long-term
goals for the inventory and the classification system: (1) describe ecologi-
cal units that have certain natural attributes in common; (2) arrange these
units in a system that will aid in resource management decisions, (3) provide
a system to inventory and map these units; and (4) provide conformity of
concepts and terminology throughout the United States. The projected level
of detail and scope of this inventory differed greatly from the previous
national wetlands inventory (Circular #39, see previous section). Because of
these differences, a new classification system had to be selected or devised.
A significant increase in wetland research in the past 15 years has pro-
duced several new classification systems. These have been, for the most
part, only regional systems. They have been too difficult to apply at a
national scale and were subsequently rejected by FWS. The FWS then elected
to construct a new classification system as the first step towards implement-
ing a new National Wetlands Inventory. The document that resulted from these
efforts was authored by L. M. Cowardin et al. (1979) and entitled "Classifica-
tion of Wetlands and Deepwater Habitats of the United States."
This wetlands classification system (Cowardin et al. 1979) uses a broad
definition of wetlands. This document includes deepwater habitats and
encompasses all aquatic systems of the U.S. within its classification system.
This reflects its intended use by people or institutions with a variety of
interests and objectives over an extremely wide geographic area.
The structure of this classification system is heirarchical, i.e., it has
several tiers or layers of classification and detail. It begins with the
most general categories or systems and progresses to more detailed categories
and descriptors. There are 5 system names, 8 subsystem names, 11 class
names, 28 subclass names, and an unspecified number of dominance types (see
Figure 2.2.1.2-a for listings to class). Each system, subsystem, class, and
subclass refers to some aspect of the vegetation, soil and hydrologic regime
that forms the basis of this classification system and characterizes specific
22
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2.2.1.2 Continued
ecotypes. The dominance types are the final biotic descriptors of this
classification system. The dominance type name is taken from the plant or
animal most characteristic of the area of interest (for example, Cypress,
Oyster). The ecosystem is described further by a series of abiotic
descriptors or modifiers referencing a particular characteristic of the water
regime (hydroperiod), water chemistry (pH, salinity), or soil type (mineral,
organic).
The result of the classification system is a unique taxon or name given
to a particular ecotype. There is no direct reference to the region in which
that taxon occurs. If a regional frame of reference is desired, the authors
(Cowardin et al. 1979) suggest the use of Bailey's (1976) ecoregion system as
a suitable way to regionalize the taxon derived from this classification
system (Figure 2.2.1.2-b).
This system was designed to be used at varying levels of detail according
to the amount of information available about a particular area and the needs
of the user. All wetlands and deepwater habitats in Region IV can be
classified by this system. Many wetlands remain to be classified dependent
on necessary funds and interest for the completion of their classification
and inventory (see Section 2.3.1.1 to 2.3.1.8).
The majority of wetlands considered in this EIS fall under the Forested
Wetland, Scrub-shrub Wetland, Emergent Wetland and Moss-Lichen Wetland
classes within the Palustrine systems (Figure 2.2.1.2-c). Emergent Wetland
classes within the Lacustrine (lakes) and Riverine (rivers) systems are also
considered as typical wetland types in Region IV and will be included in this
EIS (Figure 2.2.1.2-d and 2.2.1.2-e).
Although the FWS was primarily responsible for the creation of this class-
ification system, it did so with the cooperation of several federal agencies.
In the future it is hoped that this classification system will be adopted by
the other agencies (most notably Soil Conservation Service, Corps of
Engineers) and will establish a uniform definition of wetland types among
federal agencies. It is not, however, the intent of this classification and
inventory system to define the limits of jurisdiction of any regulatory
agency or the geographic scope of any regulatory program.
Table 2.2.1.2 provides a comparision between Circular #39 and the NWI
equivalent. The heavy lines used in Figure 2.2.1.2 show those systems of
importance for potential wastewater disposal in Region IV.
23
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Table 2.2.1.2. Comparison of Wetland Types Described in U.S. Fish and Wildlife Service Circular
#39 with Some of the Major Components of NWI System.
Circular #39 Type and References for
Examples of Typical Vegetation
Classification of Wetlands and Deepwater Habitats
Classes Water Regimes Water Chemistry
Type I—Seasonally flooded basins or flats
Wet meadow (Dix and Smeins 1967; Stewart
and Kantrud 1972)
Bottomland hardwoods (Braun 1950)
Shallow-freshwater swamps (Penfound 1952)
Type 2--Inland fresh meadows
Fen (Heinselman 1963)
Fen, northern sedge meadow (Curtis 1959)
Type 3--Inland shallow fresh marshes
Shallow marsh (Stewart and Kantrud 1972;
Golet and Larson 1974)
Type 4--Inland deep fresh marshes
Deep marsh (Stewart and Kantrud 1972;
Golet and'Larson 1974)
Type 5--Inland open freshwater
Open water (Golet and Larson 1974)
Submerged aquatic (Curtis 1959)
Type 6--Shrub swamps
Shrub swamp (Golet and Larson 1974)
Shrub-carr, alder thicket (Curtis 1959)
Emergent Wetland Temporarily flooded Fresh
Forested Wetland Intermittently Mixosaline
flooded
Emergent Wetland Saturated
Emergent Wetland
Emergent Wetland
Aquatic Bed
Aquatic Bed
Unconsolidated
Bottom
Scrub-Shrub
Wetland
Fresh
Mixosaline
Fresh
Mixosaline
Fresh
Mixosaline
Semipermanently
flooded
Seasonally flooded
Permanently flooded
Intermittently
exposed
Semipermanently
flooded
Permanently flooded Fresh
Intermittently Mixosaline
exposed
All nontidal regimes Fresh
except permanently
flooded
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Table 2.2.1.2. Continued
Circular 39 Type, and References for
Examples of Typical Vegetation
Classification of wetlands and deepwater habitats
Classes Water Regimes Water Chemistry
ro
en
Type 7—Wooded swamps
Wooded swamp (Golet and Larson 1974)
Swamps (Penfound 1952, Heinselman 1963)
Type 8--Bogs
Bog (Dansereau and Segadas-vianna 1952,
Heinselman 1963)
Pocosin (Penfound 1952, Kologiski 1977)
Type 12--Coastal shallow fresh marshes
Marsh (Anderson et al. 1968)
Estuarine bay marshes, estuarine river
marshes (Stewart 1962)
Fresh and intermediate marshes (Chabreck
1972)
Type 13—Coastal deep fresh marshes
Marsh (Anderson et al. 1968)
Estuarine bay marshes, estuarine river
marshes (Stewart 1962)
Fresh and intermediate marshes (Chabreck
1972)
Type 14—Coastal open fesh water
Estuarine bays (Stewart 1962)
Forested Wetland All nontidal regimes Fresh
except permanently
flooded
Scrub-Shrub
Wetland
Forested Wetland
Moss-Lichen
Wetland
Emergent Wetland
Saturated
Fresh
(acid only)
Regularly flooded
Irregularly flooded
Semipermanently
flooded-Tidal
Mixohaline
Fresh
Emergent Wetland Regularly flooded Mixohaline
Semipermanently Fresh
flooded-tidal
Aquatic Bed
Unconsolidated
Bottom
Subtidal
Permanently
flooded-tidal
Mixohaline
Fresh
Source: Cowardin et al. 1979.
-------
System
Subsystem
Class
i—Marine-
—Estuarine-
<
X
OS
a
a,
w
w
Q
Q
Z
w
Not Applicable
Not Applicable
iTidali
•Lower Perennial
i Riverine i
-Upper Perennial -
-Intermittent •
••LacustrineMMHBB
-Limnetic •
•Littoral i
iPalustrine i
— Rock Bottom
— Unconsolidated Bottom
Aquatic Bed
- Rocky Shore
Unconsolidated Shore
• Emergent Wetland
Rock Bottom
Unconsolidated Bottom
qua tic Bed
Rocky Shore
Unconsolidated Shore
Emergent Wetland
— Rock Bottom
—Unconsolidated Bottom
Aquatic Bed
— Rocky Shore
— Unconsolidated Shore
-Streambed
Rock Bottom
Unconsolidated Bottom
Aquatic Bed
Rock Bottom
Unconsolidated Bottom
quatic Bed
Rocky Shore
Unconsolidated Shore
Emergent Wetland
— Rock Bottom
— Unconsolidated Bottom
lAquatic Bed
(Unconsolidated Shore
iMoss-Lichen Wetland
Emergent Wetland
'Scrub-Shrub Wetland
(Forested Wetland
Figure 2.2.1.2-a. NWI wetlands classification system (wetlands applicable
to this EIS are highlighted by dark line).
Source: Cowardin et al. 1979.
26
-------
Oak-Hickory Forest
Mixed Mesophytic Forest
Appalachian Oak Forest
Ecoregions of the Southeastern
United States after Bailey (1976)
Southern Floodplain Forest
!:<&:&::•• Southeastern Mixed Forest
Beech-Sweetgum-Magnolia-Pine-Oak
Everglades
Figure 2.2.1.2-b. Ecoregions of the Southeastern United States.
Source: Adapted from Cowardin et al. 1
-------
FND
00
UPLAND PALUSTRINE UPLAND
AVERAGE WATER!
LOW WATER
Seepage Zone
a TEMPORARILY FLOODED
-------
ro
LACUSTRINE
PALUSTRINE
HIGH WATER
AVERAGE WATER
LOW WATER
a TEMPORARILY FLOODED
b SEASONALLY FLOODED
c SEMIPERMANENTLY FLOODED
d INTERMITTENTLY EXPOSED
e PERMANENTLY FLOODED
Figure 2.2.1.2-d. NWI lacustrine and palustrine wetland types.
Source: Adapted from Cowardin et al. 1979.
-------
CO
o
UPLAND PALU8TRINE
PALUSTRINE
HIGH WATER
AVERAGE WATER
LOW WATER
a TEMPORARILY FLOODED
b SEASONALLY FLOODED
c SEMIPERMANENTLY FLOODED
d INTERMITTENTLY EXPOSED
e PERMANENTLY FLOODED
Figure 2.2.1.2-e. NWI Palustrine and riverine wetland types.
Source: Adaoted from Cowardin et al. 1979.
-------
2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.2 Corps of Engineers
DUE TO WETLANDS REGULATORY RESPONSIBILITY CORPS OF ENGINEERS
MAINTAINS OWN WETLANDS DEFINITION AND CLASSIFICATION SYSTEM
The Corps of Engineers' (COE) primary interest in wetlands
is in the implementation of Section 404 (WPCA 1972)
permitting. In response, its official definition of
wetlands is broad, but recent efforts at wetlands
classification reflect a high amount of regional
specificity of wetland types.
The wetlands definitions used by the COE have evolved and expanded in
accordance with the broadening of their regulatory responsibilities by
various institutional mechanisms (see Section 5.1 for more detailed dis-
cussion). The current wetland definition used by COE was developed jointly
with EPA in 1977 (42 Federal Register July 19, 1977):
Those areas that are inundated or saturated by surface or
groundwater at a frequency and duration sufficient to
support, and that under normal circumstances do support, a
prevalence of vegetation typically adapted for life in
saturated soil conditions. Wetlands generally include
swamps, marshes, bogs, and similar areas.
The fundamental purpose of this definition is to determine whether a
specified area falls under COE jurisdiction for regulation of dredging and
filling activities in wetlands. It is implied from this definition that a
potential wetland area «will possess three unique and identifiable
characteristics (vegetation, hydrology and soils) to indicate that it is a
true wetland. While not an officially adopted policy, a number of COE
districts interpret this to imply that an area must have all three wetlands
indicators positive to fall within their definition of a wetland (Sanders
iyo£j •
Eight regional guides have been planned to assist in the implementation
of Section 404 (WPCA 1972) in regulating dredging and filling activities.
These guides employ a simple classification scheme similar to Circular #39
classification system. The COE classification scheme places freshwater
wetlands into one of four major types identified in Table 2.2.2. Guides are
currently available for all areas within Region IV. The value of these
guides lies in the description of community types, several in-depth plant
lists for particular wetland habitats and the listing of regional
differentiation of wetland types. See Figure 2.2.2 for the guide most
appropriate to the area in Region IV of interest.
31
-------
oo
ro
Table 2.2.2.
Wetland Type
The COE Wetland Classification System and Identifying Features Appropriate to
Freshwater Wetlands
1. Freshwater
aquatic
2. Freshwater
flat
3. Freshwater
marsh
4. Freshwater
swamp
Definition
Outstanding Features
Inland; flooded permanently or
semipermanently by freshwater.
Aquatic vegetation predominant
(dominant plants free-floating
or attached and having poorly
developed tissues of structural
support, supported and buoyed
up by the water).
Wetlands that have 25 percent
or less vegetative cover and
are occasionally or regularly
flooded by freshwater (e.g.,
mudflats).
Wetlands that have more than
25 percent vegetative cover of
herbaceous plants but 40 per-
cent or less cover by woody
plants that are occasionally
or regularly flooded by fresh
water (e.g., cattail marsh).
Wetlands that have more than
40 percent cover by woody
plants and are occasionally or
regularly flooded by freshwater
(e.g., cypress swamps).
Occurs along streams ponds, canals, lakes and reservoirs
as a narrow bank of vegetation in parallel with these
shoreline areas. Vegetation dense especially in sloughs,
backwater of rivers and streams or occasionally scattered.
considered early successional communities eventually
replaced by marshes, upland communities.
Most common in areas of fluctuating water levels (reservoirs
streams). Twelve dominant plant genera, varying widely in
accordance with light and soil conditions. These systems
readily change to marshes as vegetative cover increases
but returns to former state after flooding.
Major subtypes include Outer Coastal Plains Marshes,
Interior Plain Marshes (driest), Wet Meadows (savannahs,
sedge meadows). Forbs dominant in permanently wet areas,
grasses (graminoids) in seasonally wet sites. Small changes
in elevation (3"-4"j responsible for rapid changes in species
composition and boundary between this type and swamp type.
Major subtypes include Deep and Prolonged Flooding, Pro-
longed and Shallow Flooding, Floodplains with Seasonal
Flooding, Shrub-Bogs. Typical vegetative associations are
cypress, tupelo, mixed hardwood, bayheads, willow heads.
Transition to uplands sometimes gradual, distinct boundaries
sometimes difficult to detect.
Source: ACOE. 1978.
-------
INTERIOR
SOUTH
ATLANTIC
GULF COAST *
PENINSULAR
FLORIDA
Figure 2.2.2. Boundaries for COE regional wetland guides found within Region
1 V •
Source: COE. 1978.
33
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.3 Other Federal Agencies
NO OTHER FEDERAL AGENCY HAS ESTABLISHED CLASSIFICATION SYSTEMS
Although EPA has jurisdiction over wetlands, It has not
developed a separate classification system. EPA, along
with most other federal agencies, will be adopting the FWS
system.
The Fish and Wildlife Service and Corps of Engineers have been primarily
involved with wetlands classifications due to their mandates to protect
wetlands and permit activities in wetlands. EPA has regulatory respon-
sibility through involvement with 404 Permit Review, NPDES permitting, water
quality standards, and environmental protection. EPA has used the
classification systems developed by the COE and FWS rather than developing
its own system. This has provided consistency as EPA has interfaced with the
responsibilities of the COE and FWS.
Several other federal agencies have indirect jurisdiction over wetlands.
These are the Soil Conservation Service, Geological Survey, National Park
Service, and Forest Service. In each case, jurisdiction is indirect and regu-
latory powers lie with either the COE and/or EPA. As a result, these
agencies utilize the classification systems developed by the COE and FWS.
While some agencies have been utilizing the Circular #39 system of the FWS
for wetlands identification, they will gradually be adopting the new FWS
classification system.
34
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.4 Wetland Classification by Penfound
PENFOUND'S EARLY WORK WITH SOUTHERN SWAMPS AND MARSHES
HAS PRESENT VALUE
Penfound defines five general swamp types and four general
marsh types In the southeastern U.S. Important vegeta-
tlonal community types and some minor but rare asso-
ciations are also identified.
The basis for the classification and identification of many freshwater
wetlands in the southeastern United States can be traced to Penfound's review
of Southern swamps and marshes as it appeared in 1952. The area he consid-
ered ranged from Virginia to Florida and west to eastern Texas. Physio-
graphical ly, the review covers most of the Atlantic and Gulf coastal plains
and nearly all of the Mississippi alluvial plain.
The classification system was relatively simple, dividing wetlands into
salt or freshwater swamps or marshes. The major wetland types described by
Penfound (1952) applicable to this EIS are summarized in Table 2.2.4.
Penfound emphasized that soil texture is a basic factor in the local
distribution of hydric plants, but he did not include soils as part of the
classification scheme. Fire is mentioned as a factor that controls the
vegetational assemblages in certain wetlands. Eight minor swamp communities
are mentioned by Penfound and are valuable for their uniqueness. In addi-
tion, five minor freshwater marsh communities are discussed for similar
reasons.
Penfound recognized that many intergradations occur between "swamp" and
"peaty swamps." The "transitional" marsh communities have been designated as
Wet Prairies, Wet Meadows, Savannahs and Wet Pine Barrens by other investi-
gators. The term "marsh" does not ordinarily include submerged, floating, or
emergent stages of lakes or ponds in Penfound's opinion.
Penfound's classification system is straightforward and informative but
lacks specificity for regulatory or inventory usage. However, many classifi-
cation systems developed since 1952 have been based on his system.
35
-------
00
CD
Table 2.2.4. Major Freshwater Southeastern Wetland Types as Classified by Penfound (1952).
Wetland Type Definition Characteristics Major Communities*
Fresh Hater Swamps
Deep Swamps
Deep swamps are fresh water, woody
communities, with surface water
throughout most or all of the growing
season.
Relatively tall, deciduous trees,
with swollen bases and "knees,"
and abundant epiphytes. Frutes-
cent and herbaceous species few
or none.
Southern cypress-tupelo gum (Taxodium
distichum-Nyssa aquatica).
Swamp gum-pond cypress (Nyssa biflora-
Taxodium ascendens).
Shallow Swamps (transitional communities)
Shallow swamps are freshwater, woody
communities, the soil of which is
inundated for only short periods
during the growing season.
Peaty Swamps
Peaty swamps are oxylic, peat-forming,
sclerophyllous woody communities,
with surface water only during a part
of the growing season.
Fresh Hater Marshes
Deep Marshes
Deep marshes are freshwater grass-
sedge-rush communities the soil of
which is covered by water throughout
most or all of the growing season.
Deciduous trees or shrubs without Black willow-sandbar willow
evident hydrophytic characters
except for production of water
roots in buttonball and willows
and swollen bases in green ash.
Sclerophyl lous, evergreen trees or
shrubs, including many ericaceous
species. Frutescent and herba-
ceous plants numerous.
Salix interior
Buttonball-dogwood-willow (Cephalanthus-
Svida-Salix).
Overcup oak-water hickory (Quercus lyrata-
Hicoria aquatica).
Hackberry-elm-ash (Celtis-Ulmus-Fraxinus).
Maple-red gum-oak (Rufacer-Liquidambar-Quercus),
Alder-birch (Alnus-Betula).
Red bay-sweet bay (Tamala pubescens-Magnolia
virginiana).
Pond pine-slash pine
caribaea).
(Pinus serotina-Pinus
Southern white cedar (Chamaecyparis thyoides).
Evergreen shrub swamp (TTex-Cyri1l¥-Zenob1a).
Giant cut grass (Zizani opsis mi 1acca).
Cattai1-Bulrush-maiden cane (Typha-Sclrpus-
Panicum).
Saw-grass (Mariscus jamaicensis).
Shallow Marshes (wet meadows)
Shallow marshes are freshwater, grass-
sedge-rush communities, in which surface
water is usually present for only a
small part of the growing season.
Panic grass-horned rush (Panicum-Rynchospora).
*Plant names according to Small (1933)
Source: Adapted from Penfound. 1952.
-------
2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.5 Goodwin and Niering's Classification of Significant Natural
Wetlands
GOODWIN AND NIERING UTILIZE FWS CLASSIFICATION
SYSTEM WITH ALTERATIONS
The classification systems developed by Goodwin and
Niering follows closely the FWS system in Circular 139.
The new system was applied to inventory the significant
inland wetlands of the U.S. The FWS systen was amplified
to include habitats of relatively little importance to
waterfowl .
The classification system developed by Goodwin and Niering (1975) con-
siders only freshwater and inland wetlands. Wetlands are recognized as a
sue where the water table is near, at, or above the surface of the ground
for at least some portion of the growing season. Floodplains are included in
tn s classification as are lakes and ponds where they are ecologically
related to specific wetland types. 3 J
Marshes, swamps and bogs are considered to constitute the major types of
wetlands as in Penfound (1952) and Martin et al . (1953). It is acknowledged
that each wetland type may exhibit various phases or subtypes. Goodwin and
Niering s classification system was employed in a survey of significant
Landmarks ^ recommendat1ons regarding their potential as National
In the following paragraphs the classification types for freshwater
wetlands are summarized. The letter after the type refers to fresh (F) as
opposed to saline (S) wetlands. The number following this letter refers to
nrr,n°rrel?S 1ng- Classification Tn Circular #39. If no number appears, no
wetland if * K *Fm ™ IK"^' Jche,final le«er indicates whether the
wetland is a Marsh (M), a Shrub Swamp (Ss), a Wooded Swamp (Sw), or a Bog
.... .fT'! r100?6!*33!1"5 and f1a*s (f-V' These Sltes are inundated
periodically Dut not flooded during the growing season. They occur along
water courses and on floodplains, especially in the lower Mississippi drain-
?h9! duration of ffnn^f* ^V vf***?m is dependent upon the season and
rnL ? fl°odln9- Bottomland forests along rivers (F-l-Sw) may be
stTcifl,?^9TnSH (M£i S??0', °3kS .(SiiSrcus spp.), sweet gum (Liquidambar
styraciflua), and cypress (Taxodium d^stichum) in the South and Southeast.
Fresh Meadows (F-2-M). The water table is at or near the surface but
e surace u
tic" irS16trv f1S rHStand1ng Water* Such Sites often exhibit a Mchfio-
tic diversity including grasses, sedges and rushes.
Shallow Fresh Marshes (F-3-M). The soil is waterlogged throughout the
wat9Pr VeaS°n' anlthe SiteS are often covered with six Inchesor more of
water. They occur throughout the United States as shallow basins and
sloughs and along the margins of shallow lakes or the border? of deep
37
-------
2.2.5 Continued
marshes. The vegetation is dominated primarily by emergent aquatic plants.
Deep Fresh Marshes (F-4-M). This type includes natural shallow ponds,
springs, and man-made impoundments usually less than 10 feet in depth. These
areas include shallow lakes, sloughs, potholes, limestone sinks and margins
of open water areas.
Open Fresh Water (F-5-M). This includes natural shallow ponds, springs
and man-made impoundments usually less than 10 feet in depth. These are
widespread but most abundant in Florida. The vegetation of the marginal zone
is dominated by emergent vegetation (see F-3-M); the deeper areas by floating
and submerged aquatics (see F-4-M).
Shrub Swamps (F-6-Ss) (sometimes referred to as carrs). The water table
is at or near the surface throughout much of the year, and these areas may be
flooded with as much as 6-12 inches of water at certain periods. Such swamps
occur throughout the deciduous forest region in upland depress2.2.5
Continued
Wooded Swamps (F-7-Sw). The water table is at or near the surface
throughout the year, and 6-12 inches of standing water during part of the
year is common. These occur in poorly drained upland sites along streams,
shallow river basins and deltas. The vegetation includes a vast acreage of
bottomland hardwoods and cypress swamps of the Southeast. The Great Cypress
Swamp of west Florida is one of the most extensive of such areas in North
America. Although river floodplain swamp forests intergrade with seasonally
flooded swamp forests (F-l Sw), those more continuously flooded throughout
the year are included here. Shrub and wooded swamp types may also inter-
grade. Forest composition varies geographically. In the Southeast primary
trees are cypress (Taxodium spp.), water oak (Quercus nigra), tupelo gum
(Nyssa aquatica), and pond pine (Pinus rigida var. serotina).
Bogs (F-8-B). These usually develop in deep lakes and poorly drained
depressions of glacial origin and are underlain by extensive peat deposits.
They occur throughout the glaciated regions of the United States on the
Coastal Plain. They are represented in the Carolina Bay regions.
Riparian (R). These habitats consist of narrow bands of vegetation found
along water courses. They may be transitional between seasonally flooded
types (F-l) and more mesic vegetation. In some instances their flora is
unique.
38
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.2 Wetland Classification Systems
2.2.6 Miscellaneous Classification Systems
OTHER CLASSIFICATION SYSTEMS MEET SPECIFIC NEEDS OF USER
Appropriate wetland classification schemes should meet the
needs of the user. Several diverse systems include the
traditional vegetational-hydrologic approach and several
value-type classifications.
Several alternative approaches to wetland classifications are available.
The ultimate classification system selected should reflect the needs of the
individual user, so many wetland classification systems are modified to suit
those needs. A wetland classification system may relate to one aspect of
wetlands (vegetation, soils, etc.) or to any combination of parameters
associated with wetlands.
Several legal or regulatory wetland classification systems have been
discussed earlier. Other classification systems are used for decision
making, ecological/scientific purposes or are popular because of their
widespread use.
Kuchler (1964), for example, classified wetlands of the U.S. by
distinctive vegetative types (Table 2.6-a). Another approach to wetland
classification is to assess values of wetlands. Over 20 methodologies have
been developed to assess the various aspects of wetland values including
habitat, hydrology, agriculture/silviculture, recreation and heritage
functions, and geographic features. Leonard et al. (1981) reviewed and
analyzed the methodologies for assessment of these wetland values.
Several classification schemes exist that apply only within a specific
region. For example, 25 wetlands types were identified based on vegetation
and hydrologic considerations for the Forested Wetlands of Florida Study (see
Table 2.6-b). Steward and Kantrud (1971) and Golet and Larson (1974) are
responsible for other classification systems that are widely used and
applicable to specific wetland regions outside Region IV.
39
-------
Table 2.2.6-a. Ku'chler's Wetland Vegetation Types,
Type
No.
49
78
79
80
91
92
94
98
113
114
Name
Tule Marshes
Southern Cord-
grass Prairie
Palmetto Prairie
Marl Everglades
Grassland
Hammocks
Cypress
Savanna
Everglades
Grassland
Bayheads
Conifer bog
Northern Flood-
plain Forest
Southern Flood-
plain Forest
Pocosin
Dominant plants
Scirpus, Typha
Spartina al term' flora
Aristida stricta
Serenoa repens
Cladium jamaicense
Persea borbonia
Taxodium distichum
Aristida, Taxodium,
Cladium
Cladium
Magnolia virginiana
Persea borbonia
Larix laricina
Picea mariana
Thuja occidental is
Populus deltoides
Sal ix nigra, Ulmus spp.
Nyssa aquatica, Quercus
spp. Taxodium
Pinus serotina
Ilex glabra
Location
Widespread;
esp. Cal. and Utah
Southeast Tex.;
Southern La.
Central Fla.
South Fla.
South Fla.
South Fla.
South Fla.
South Fla.
Glaciated
eastern and
central states
Midwestern
river bottoms
South and
Southeast
Coastal Plain
Va. to S.C.
Source: Goodwin and Niering 1975.
40
-------
Table 2.2.6-b. Forested Wetlands of Florida,
Cypress Ponds (domes) - stillwater
Acid Water Ponds
Hardwater Ponds
Pasture Ponds
Enriched Ponds
Other Non-Stream Swamps
Gum Pond (swamp)
Lake Border Swamp
Dwarf Cypress
Bog Swamp (Okeefenokee Swamp)
Bay Swamp
Shrub Bog
Herb Bog
Seepage Swamp
Hydric Hammock (North Florida type)
South Florida Hammock
Melaleuca Swamp
Cypress Strand - slowly flowing water
River Swamps and Floodplains
Alluvial River Swamps
Blackwater River and Creek Swamps
Backswamp
Spring Run Swamp
Tidewater Swamp
Saltwater Swamps - Mangroves
Riverine Black Mangroves
Fringe Red Mangroves
Overwash Red Mangroves
Scrub Mangroves
Source: Wharton et al. 1976.
41
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2.0 WETLANDS DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
A COMPREHENSIVE WETLAND INVENTORY HAS NOT BEEN UNDERTAKEN BY ANY STATE
Each of the eight states In Region IV has had limited
wetland maps prepared, primarily In association with
specific coastal or river basin studies. Several federal
agencies are involved in wetlands classification and
mapping in conjunction with other responsibilities. The
U.S. Fish and Wildlife Service (FWS) National Wetlands
Inventory is currently the only comprehensive wetlands
mapping project in Region IV.
The most extensive and detailed wetland mapping projects in Region IV
have generally been conducted along the coastal regions. Freshwater wetlands
are generally included in these projects but are usually a minor portion of
the mapping effort. In several instances, coastal wetlands have been mapped
by both state and federal agencies. The relative emphasis placed on coastal
mapping is directly related to the recently accelerating coastal development
pressures, the vital and often conflicting coastal interests (navigation,
fish and wildlife habitat, tourism, energy development) and the availability
of funding resources, primarily through the federal Coastal Zone Management
Program.
Additional wetland classification and mapping projects have been done by
a variety of state and federal agencies, primarily in association with
specific river basin studies. The USDA Soil Conservation Service has mapped
wetlands in the Northeast Gulf Rivers Basin and the Alabama River Basin. The
Ohio River Basin Commission has mapped wetlands along the Ohio River Basin in
Kentucky. The Obion, Forked Deer and Hatchie River Basins in west Tennessee
have been mapped by several agencies. The St. Johns River Basin in Florida
has been extensively mapped by the University of Florida Center for Wetlands,
and the Santee and Cooper River Basins in South Carolina are being mapped in
great detail by the South Carolina Wildlife and Marine Resources Department.
Additional river basin wetlands mapping has been conducted in Mississippi by
the Mississippi State University Remote Sensing Center.
In addition to the specific wetland mapping projects outlined above,
several federal agencies are involved in generalized wetland mapping in con-
junction with their other responsibilities. The USDA-Soil Conservation
Service has prepared detailed soils maps covering most of Region IV. These
maps delineate soils and can be used as a general indication of wetland
areas. The standard U.S. Geological Survey 7.5-minute quadrangle maps also
indicate wetland areas on a generalized basis. The U.S. Forest Service has
been involved with various mapping efforts concerning forest resources in
Region IV. In some instances, these maps indicate wetland areas in relation
to forest resources.
The National Wetlands Inventory conducted by the FWS is the most compre-
hensive mapping effort in Region IV; however, this current inventory has been
preceded by other national inventories. In 1906 and 1922 the U.S. Department
of Agriculture prepared national inventories to determine wetland areas
42
-------
2.3 Continued
suitable for agriculture. In 1954, the FWS conducted a national inventory to
assess the amount and type of valuable waterfowl habitat. Based on a classi-
fication system developed by Martin et al. (1953) specifically for the
inventory, the results of the inventory and an illustrated description of the
types were published by FWS as Circular #39 (Shaw and Fredine 1956) (see
Section 2.2.1). In 1975 the National Park Service completed an inventory of
inland wetlands as part of the Natural Landmarks Program. This project was
undertaken to identify significant inland wetlands for possible designation
as Registered Natural Landmarks. A total of 43 significant wetlands were
identified and classified in the eight Region IV states (Goodwin and Niering
1975).
The FWS, as part of the current National Wetlands Inventory, has com-
pleted maps in portions of each Region IV state, except Kentucky. Again,
most mapping has been done along the coast. However, extensive mapping has
also been done in the Mississippi River Basin and along the Tennessee-Tom-
bigbee Waterway in association with the Corps of Engineers. The figures
accompanying each of the following sections (2.3.1 through 2.3.8) illustrate
the status of the FWS National Wetlands Inventory as of March 1982.
43
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2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.1 Alabama
WETLANDS MAPPING IN ALABAMA HAS BEEN DONE IN COASTAL COUNTIES AND
ALONG THE TENNESSEE-TOMBIGBEE WATERWAY
Several wetlands mapping projects have been undertaken In
recent years by the Alabama Marine Environmental Sciences
Consortium in Mobile and Baldwin Counties. The USDA Soil
Conservation Service has also mapped wetlands in the
Northeast Gulf Rivers Basin and the Alabama River Basin.
The U.S. Fish and Wildlife Service (National Wetlands
Inventory) has mapped wetlands along the
Tennessee-Tombigbee Waterway.
The federal government has been the major impetus behind most wetland
mapping projects in Alabama. Using incentives provided by the federal
Coastal Zone Management Act, the Alabama Marine Environmental Sciences
Consortium has conducted a series of wetland mapping projects over the past
seven years in Mobile and Baldwin Counties. Earlier mapping efforts focused
on salt and brackish water habitats and ecologically critical areas along the
Gulf Coast. However, the most recently completed project focused primarily
on the freshwater wetland communities below the 10-foot contour. A current
mapping project scheduled for completion in late 1982 will complete the
mapping of freshwater habitats in the northern portion of the two coastal
counties. Most coastal wetlands mapping has been conducted at a scale of
1:24,000 with a vegetational classification system developed by the state.
Mapping of wetlands in the Northeast Gulf Rivers Basin and the Alabama
River Basin was completed in 1976 by the USDA-Soil Conservation Service.
These maps, prepared in response to regional and local planning needs, were
developed at a scale of 1:24,000 using USGS 7.5-minute topographic maps.
County road maps and county photo index maps (Alabama River Basin) were used
when USGS maps were unavailable. Additional wetlands mapping or updating of
existing maps has not been done by the USDA-SCS.
Mapping along the Tennessee-Tombigbee Waterway has been done by the U.S.
Fish and Wildlife Service in conjunction with the Corps of Engineers as part
of the National Wetlands Inventory. Based on the FWS classification system
(Cowardin et al. 1979), these maps are detailed along the waterway but are
incomplete farther away.
Table 2.3.1 summarizes the mapping efforts to date in Alabama.
44
-------
Table 2.3.1. Wetland Inventories in Alabama.
Inventory Coverage Classification
Scale
Date
Resolution
Agency
All All coastal wetlands
in Mobile and Baldwin
Counties up to the in-
land/upland boundary
(primarily salt/brackish
habitats)
Vegetational
(species)
1:24,000 1976
1 acre
Alabama Development Office
Ala. Coastal Area Board
AL2 All coastal wetlands up
to the 50' contour
(ecologically critical
areas)
Vegetational
(community)
1:24,000 1975
1:62,500
1-3 acres Marine Environmental Science
Consortium
Dauphin Island Sea Lab
AL3 Northeast Gulf Rivers
Basin
Vegetational 1:24,000 1976 20 acres
(Martin et al.)
USDA Soil Conservation
Service
en
AL4 Alabama River Basin
Vegetational 1:24,000 1976 20 acres
(Martin et al.)
USDA Soil Conservation
Service
AL5 Lower Mobile delta
(primarily freshwater
marshes)
Vegetational
(species)
1963
Ala. Dept. of Conservation -
Pittman-Robinson Project
(F. X. Lueth)
AL6 All coastal wetlands
in Mobile and Baldwin
Counties below the 10'
contour, south of the
Hwy 90 causeway
Vegetational
(community)
1:24,000 1981
1 acre
Marine Environmental Science
Consortium
Dauphin Island Sea Lab
-------
Table 2.3.1 Continued
Inventory Coverage
Classification Scale Date Resolution Agency
AL7 All coastal wetlands
in Mobile and Baldwin
Counties below the 10'
contour, north of the
Hwy 90 causeway
Vegetational
(community)
1:24,000 1983
1 acre
Marine Environmental Sciences
Consortium
Dauphin Island Sea Lab
(currently being conducted -
available late 1982-1983)
AL8 Tennessee-Tombigbee
Waterway (National
Wetlands Inventory)
Hydrology/Soils 1:24,000
Vegetation 1:100,000
(Cowardin et al.)
to the subclass
and water regime
level
1982
1 acre
U.S. Fish and Wildlife
Service in conjunction with
the U.S. Army Corps of
Engineers
O1
Source: Claude Terry & Associates, Inc. 1982.
-------
LEGEND
MAY 1981
(5 IN PROGRESS
3 LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
9 LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
• SMALL SCALE MAP AVAILABLE
© SMALL SCALE MAPS ONLY
Figure 2.3.1. Status of the National Wetlands Inventory in Alabama,
Source: U.S. Fish and Wildlife Service. April 1982.
47
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.2 Florida
FLORIDA WETLANDS HAVE BEEN EXTENSIVELY MAPPED, GENERALLY AT LARGE SCALES
Coastal and Inland wetlands throughout Florida have been
mapped at generally larger scales than other states'
mapping efforts. The most extensive mapping of freshwater
wetlands has been done by the University of Florida Center
for Wetlands In conjunction with state Water Management
Districts.
Extensive wetlands mapping has been done throughout Florida, particularly
in south Florida. Since south Florida is outside the scope of this EIS these
mapping projects will not be discussed in detail; however, information
concerning these projects is included in Table 2.3.2.
Mapping projects with the greatest relevancy to this EIS have been
conducted by the University of Florida Center for Wetlands and the USDA Soil
Conservation Service. In 1976, the Center for Wetlands mapped forested
wetlands throughout the state at a scale of 1:500,000. Although several
categories of wetlands were classified for that project, all categories were
mapped as forested wetlands. The USDA-SCS also mapped wetlands in the
Northeast Gulf Rivers Basin in 1976. Based on vegetative community and/or
soil types, the USDA-SCS project provided maps in greater detail at a scale
of 1:24,000. In 1979, the Center for Wetlands prepared wetland maps for the
St. Johns River Water Management District (northeast Florida). Again, these
maps were prepared at the relatively large scales of 1:63,360 (1 inch = 1
mile) and 1:253,440 (1 inch = 4 miles). However, this recent mapping effort
by the Center for Wetlands provided greater detail through the use of several
freshwater wetland categories based on vegetational communities.
The U.S. Fish and Wildlife Service has also been active in wetlands
mapping in Florida as part of the National Wetlands Inventory. Most of south
Florida has been completely mapped at both scales (1:24,000 and 1:100,000).
Draft maps in both scales have recently been completed for northwest Florida.
Table 2.3.2 summarizes the mapping efforts to date in Florida.
48
-------
Table 2.3.2 Wetland Inventories in Florida.
Inventory Coverage Classification
Scale
Date
Resolution
Agency
Fl Wetlands in the Kissimmee- Vegetational 1:500,000 -
Everglades Basin of community 1:250,000
south Florida (Univ. of Fla.) 1:154,000
1:77,116
University of Florida
Center for Wetlands
F2 Forested wetlands
throughout the state
Vegetational
community/hy-
drology
(Univ. of Fla.)
1:500,000 1976
10 acres
University of Florida
Center for Wetlands
F3 Northeast Gulf River
Basin
Vegetational
community/
soils (FDNR)
1:24,000 1976
USDA Soil Conservation
Service
F4
Central and Southern
Florida Flood Control
District
Vegetational
community/
hydrology
1:500,000 1976
1:24,000
10 acres
2 acres
South Florida Water
Management District
F5 Coastal wetlands
Vegetational
community
(Anderson et al.)
1:125,000 1975
40 acres
Fla. Dept. of Natural
Resources - Bureau of
Coastal Zone Planning
F6 Wetlands in the St. Johns Vegetational
River Water Management community
District (northeast (Univ. of Fla.)
Florida)
1:63,360 1979
1:253,440
15 acres
University of Florida
Center for Wetlands
F7 South and Northwest
Florida (National Wet-
lands Inventory)
Hydrology/Soils/ 1:
Vegetation 1:
(Cowardin et al.)
to the subclass
and water regime
level.
24,000
100,000
1982
1 acre
U.S. Fish and Wildlife
Service
Source: Claude Terry & Associates, Inc. 1982.
-------
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
• SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.2. Status of the National Wetlands Inventory in Florida.
Source: U.S. Fish and Wildlife Service. April 1982.
50
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.3 Georgia
COASTAL AREAS EXTENSIVELY MAPPED; INLAND AREAS MAPPED WITH LANDSAT DATA
The coastal areas of Georgia, including the barrier
islands, have been extensively mapped by the Georgia
Coastal Resources Division, the USDA Soil Conservation
Service and the U.S. Fish and Wildlife Service. The
entire state has been mapped using LANDSAT imagery; these
maps provide generalized wetland locations without
detailed classification.
The most detailed wetlands mapping in Georgia has been done for the eight
coastal counties by a variety of state and federal agencies. The earliest
mapping project was completed by the USDA Soil Conservation Service in 1977.
This project used aerial photographs to classify and map coastal wetlands at
the scales of 1:20,000 and 1:24,000, resulting in computer-reproduced maps as
part of the Map Information Assembly and Display System (MIADS). Additional
coastal wetlands mapping has been completed for the coastal barrier islands
by a variety of agencies and organizations. Prepared as part of individual
resource planning studies, these maps are generally available from the
Georgia Coastal Resources Division of the Department of Natural Resources.
The U.S. Fish and Wildlife Service has also mapped coastal Georgia as
part of the National Wetlands Inventory. These maps are based on the classi-
fication system developed by Cowardin et al. (1979) and are available at
scales of 1:24,000 and 1:100,000. In Georgia, wetlands were classified only
to the class level (see Section 2.2.1).
Wetlands mapping for the inland areas of Georgia has only been done on
a generalized basis using LANDSAT imagery. In 1977, the Georgia Office of
Planning and Research (GaDNR) prepared statewide maps indicating vegetative
cover and land use. Based on LANDSAT imagery, these maps provide delineation
of bottomland wetlands. Additional delineations according to vegetative
communities are possible, depending on the time (season, tidal level) of
photography. The USDA-SCS has recently completed generalized wetlands
mapping as part of a Southwest River Basin Study covering portions of 32
Georgia counties. Prepared at a scale of 1:250,000, this river basin study
is based on color-enhanced LANDSAT data.
The Georgia Department of Community Affairs is currently involved in
another mapping project using LANDSAT imagery. Using data from March, 1981,
this mapping project is being done on three levels: statewide (1:500,000);
for three Area Planning and Development Commissions (APDC) (1:100,000); and
three counties (1:50,000). These maps will provide generalized land cover
and land use information similar to previous projects involving LANDSAT
imagery. • M
51
-------
Table 2.3.3 Wetland Inventories in Georgia.
en
ro
Inventory Coverage
Gl Coastal wetlands
(eight coastal counties)
G2
Coastal wetlands
(National Wetlands
Inventory)
G3 Coastal wetlands
on barrier islands
G4 Statewide land classi-
fi cati on/vegetati ve
cover
G5 Selected areas of the
state (Northeast, South
and Southwest APDCs)
Classification Scale
Date
Vegetational
community/
hydrology/soils
(Martin et al.)
1:20,000
1:24,000
1977
Hydrology/Soils/ 1:24,000 1982
Vegetation 1:100,000
(Cowardin et al.)
classified only
to the class level
LANDSAT data
varied
1977
LANDSAT data
1:100,000 1982
1:50,000
Source: Claude Terry & Associates, Inc. 1982.
Resolution
1 acre
1 acre
1 acre
Agency
3-10 acres USDA Soil Conservation
Service
U.S. Fish and Wildlife
Service
Ga. Dept. of Natural
Resources, Coastal
Resources Division
Ga. Dept. of Natural
Resources, Office of
Planning & Research
Ga. Dept. of Community
Affairs
-------
LEGEND
MAY 1981
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.3. Status of the National Wetlands Inventory in Georgia
Source: U.S. Fish and Wildlife Service. April 1982.
53
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.4 Kentucky
LIMITED MAPPING FOCUSED ON THE OHIO RIVER AND THE KENTUCKY COALFIELDS
The Ohio River Basin Commission has mapped wetlands along
the Ohio River. The EPA, in conjunction with the Kentucky
Nature Preserves Commission, has mapped wetlands in the
Eastern and Western Kentucky coalfields. However, a com-
prehensive wetlands mapping effort has not been undertaken
in Kentucky.
While wetlands mapping efforts have been recent in Kentucky, they gen-
erally have not been extensive or comprehensive. In 1977 the Ohio River
Basin Commission completed wetlands mapping along the Ohio River in Kentucky.
Using the FWS Circular #39 classification system, wetlands were mapped at a
scale of 1:24,000 (USGS quadrangle maps). While these maps are detailed
along the Ohio River, inland areas are less detailed.
The EPA in conjunction with the Kentucky Nature Preserves Commission has
prepared maps of the Western and Eastern Kentucky coalfields (Environmental
Atlas Series). Using a generalized classification system, wetlands were
mapped at a scale of 1:24,000, primarily from aerial photographs. The maps
of the Eastern Kentucky coalfields (1979) detail very few wetlands; the maps
for the Western Kentucky coalfields (1980) contain more extensive wetlands
mapping.
Additional projects have been undertaken in Kentucky providing detailed
wetlands mapping on a more localized level. The University of Louisville is
currently involved in a research project also concerning the Western Kentucky
coalfields. As part of this project a detailed analysis of wetlands at three
specific sites in Hopkins, Muhlenberg and Henderson Counties has been com-
pleted by Mitsch et al. (1982). As a continuance of that project, an atlas
of wetlands for a 1,500 mi2 region of intense surface mining is now in draft
stage. This mapping effort uses a modified FWS classification system and
provides more detail than the EPA project.
The Kentucky Nature Preserves Commission has also prepared maps indicat-
ing wetlands in an oil shale region near the Eastern Kentucky coalfields
(Knob Study 1981). This mapping effort was prepared at a scale of 1:24,000.
The FWS, as part of a Unique Ecosystem Study, has assembled detailed
information, including maps, on bottomland hardwood areas in Hickman and
Fulton Counties. This project was undertaken to identify and quantify the
acreage of particular habitats. These maps include detailed information on
land ownership. The FWS has not done any mapping in Kentucky as part of the
National Wetlands Inventory.
Table 2.3.4 summarizes the mapping efforts to date in Kentucky.
54
-------
Table 2.3.4 Wetland Inventories in Kentucky.
Inventory Coverage
Classification Scale Date Resolution Agency
Kl
K2
K3
K4
Ohio River Basin
Western Kentucky
Coalfields
Eastern Kentucky
Coalfields
Oil Shale Region/
Eastern Kentucky
Coalfields (limited)
FWS - 1:24,000 1977
Circular 39
Vegetational/ 1:24,000 1980
hydrological
Vegetational/ 1:24,000 1979
hydrological
Vegetational/ 1:24,000 1981
hydrological
Ohio River Basin Commiss
EPA - Kentucky Nature
Preserves Commission
EPA - Kentucky Nature
Preserves Commission
Kentucky Nature Preserve
Commission (Knobs Study)
K5 Western Kentucky
Coalfields (1500 mi2
region in heavy
surface mining)
Vegetational/ 1:24,000 1982
hydrological
(modified FWS)
University of Louisville-
funded by OSM and OWRT
(Dept. of Interior)
K6 Hickman and Fulton
Counties
FWS
1981
FWS
Source: Claude Terry & Associates, Inc. 1982.
-------
LEGEND
MAY 1981
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.4. Status of the National Wetlands Inventory in Kentucky.
Source: U.S. Fish and Wildlife Service. April 1982.
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.5 Mississippi
EXTENSIVE MAPPING COMPLETED IN MISSISSIPPI
The National Wetlands Inventory has completely mapped
areas along the Mississippi River and partially mapped
areas along the Tennessee-Tombigbee Waterway. Coastal
wetlands and marshes have been mapped in the three coastal
counties. The Mississippi State University Renote Sensing
Center has completed wetland mapping projects along
various inland waterways.
The most extensive wetlands mapping in Mississippi has been completed as
part of the National Inventory by the U.S. Fish and Wildlife Service. Maps
have been completed at two scales (1:24,000 and 1:100,000) within the
Mississippi River Basin. Large-scale maps (1:24,000) have also been
completed along the Tennessee-Tombigbee Waterway in conjunction with the
Corps of Engineers. These maps are generally detailed along the waterway and
less detailed away from the canal. Partial mapping has also been completed
as part of the National Wetlands Inventory in southwest Mississippi.
Coastal wetlands and marshes have also been mapped in Mississippi. Wet-
lands in the three coastal counties, Jackson, Harrison and Hancock, were
mapped in 1973 by the Mississippi Marine Resources Council. Prepared at a
scale of 1:24,000, these maps indicate the generalized location of coastal
wetlands for jurisdictional purposes. Coastal marshes associated with the
St. Louis, Biloxi and Pascagoula estuarine systems were also mapped in 1973
by the Gulf Coast Research Laboratory. Saltwater wetlands were the primary
focus of both of these mapping efforts although freshwater wetlands may have
been included.
Additional mapping of inland freshwater wetlands has been done by the
Remote Sensing Center at the Mississippi State University. The wetlands
mapping project undertaken at MSU vary in scope and scale and are usually
prepared in conjunction with various federal agencies, such as the U.S. Army
ion?? °f Eng1neers and the Federal Energy Regulatory Commission (Miller
iyo£) •
Table 2.3.5 summarizes the mapping efforts to date in Mississippi.
57
-------
Table 2.3.5 Wetland Inventories in Mississippi.
Ml
Inventory Coverage
Coastal Wetlands in
Jackson, Harrison and
Hancock Counties
Classification
no formal
classification
Scale
1:24,000
Date
1973
Resolution
1 acre
Agency
Miss. Marine Resources
Council (Bureau of Marin
Resources)
M2 Coastal Marshes
(St. Louis, Biloxi
and Pascagoula estu-
arine systems)
Vegetational
(Penfound &
Hathaway)
1:62,500 1973
Gulf Coast Research
Laboratory, Ocean Springs,
MS
en
00
M3 Various inland water-
ways and river basins
(localized)
Microtopography/ Varied
vegetative (1:12,000 -
1:24,000)
1-5 acres Mississippi State Univ.
Remote Sensing Center
M4 Tennessee-Tombigbee
Waterway/Mi ssi ssi ppi
River Basin (National
Wetlands Inventory)
Hydrology/Soils 1:24,000 1982
Vegetation 1:100,000
(Cowardin et al.)
to the subclass
and water regime
level
1 acre
U.S. Fish and Wildlife
Service
Source: Claude Terry & Associates, Inc. 1982.
-------
LEGEND
MAY 1981
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.5. Status of the National Wetlands Inventory in Mississippi
Source: U.S. Fish and Wildlife Service. April 1982.
59
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.6 North Carolina
LIMITED MAPPING HAS BEEN DONE IN THE NORTH CAROLINA COASTAL PLAIN
Mapping efforts have been relatively limited in North
Carolina, confined primarily to the coastal plain. Wilson
(1962) and Richardson (1981) have mapped wetlands at a
small scale (1:250,000) along the entire coastal plain of
North Carolina. The U.S. Fish and Wildlife Service and
the U.S. Environmental Protection Agency have prepared
more detailed maps on a smaller area of the North Carolina
coast.
One of the first extensive wetlands mapping efforts in North Carolina was
conducted by Wilson in the late 1950's. This mapping project was one of the
initial applications of the FWS Circular #39 classification system. With
this project, wetlands in the 41 Coastal Plain Counties were mapped at a
scale of 1:250,000. The N.C. Office of Coastal Management is currently re-
producing these maps at a larger scale of 1:24,000. The original mapping
effort is important in that it has formed a basis for subsequent studies
concerning historical changes in North Carolina wetlands.
In 1979, Richardson used LANDSAT imagery to identify and map pocosins in
the North Carolina coastal plain. A final map was produced at a scale of
1:250,000, although working maps were prepared on North Carolina Department
of Transportation county maps (1:126,720).
More recent mapping efforts have been undertaken in North Carolina but on
a less extensive scale than previous efforts. The EPA is currently mapping
wetlands in the several counties located between Albermarle and Pamlico
Sounds. Prepared at a scale of 1:24,000 from 1981 color-infrared aerial
photographs, these maps are being prepared in response to extensive land
clearing activities in this area. The FWS has also prepared large-scale maps
(1:24,000) for the Currituck Sound area as part of the National Wetlands
Inventory. This represents the only mapping in North Carolina for the
National Wetlands Inventory.
Table 2.3.6 summarizes the mapping efforts to date in North Carolina.
60
-------
Table 2.3.6 Wetland Inventories in North Carolina.
Inventory Coverage
Classification Scale Date Resolution Agency
NCI Coastal Plains of
N.C. (41 counties)
Vegetational
(FWS Circular
#39)
1:250,000 1962 40 acres
N.C. Office of Coastal
Management
NC2 Currituck Sound (Nation-
al Wetlands Inventory)
Hydrology/Soils/ 1:24,000
Vegetation
(Cowardin et al.)
to the subclass and
water regime level
1982
1 acre
U.S. Fish and Wildlife
Service
NC3 Pocosins of the N.C.
coastal plain
(41 counties)
Vegetational
(Wilson 1962)
Land use
1:250,000 1980
Duke University, School
of Forestry
NC4 Peninsula between
Albemarle and Pamlico
Sounds
Vegetational
1:24,000 1982 1 acre
U.S. Environmental
Protection Agency
Source: Claude Terry & Associates, Inc. 1982.
-------
en
IV)
LEGEND
MAY 1981
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.6. Status of the National Wetlands Inventory in North Carolina,
Source: U.S. Fish and Wildlife Service. April 1982.
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.7 South Carolina
ONLY THE COASTAL PLAIN OF SOUTH CAROLINA HAS BEEN MAPPED
The U.S. Fish and Wildlife Service and the S.C. Wildlife
and Marine Resources Department are the only agencies
involved with wetlands mapping in South Carolina. Only
the coastal plain and tidal areas of South Carolina have
been mapped.
The South Carolina Wildlife and Marine Resources Department (SCWMRD)
prepared maps of all non-forested tidal wetlands in 1976. Prepared at a
scale of 1:24,000 with a minimum mapping area of one acre, these maps were
never officially published. A current mapping effort is being undertaken by
the SCWMRD in conjunction with the U.S. Fish and Wildlife Service concerning
the Santee and Cooper River Basins. Initiated in anticipation of a proposed
river diversion project, this mapping project is based on the FWS classifi-
cation system (Cowardin et al. 1979), including the use of special modifiers
to provide greater detail. These maps are being prepared at a scale of
1:24,000 and should be available by July 1982.
The FWS has also prepared extensive wetland maps of the South Carolina
coastal plain as part of the National Wetlands Inventory. These maps are
available at both large (1:24,000) and small scales (1:100,000).
Table 2.3.7 summarizes the mapping efforts to date in South Carolina.
63
-------
Table 2.3.7 Wetland Inventories in South Carolina.
Inventory Coverage
Classification Scale Date Resolution Agency
SCI Non-forested tidal
wetlands (not published)
Vegetational
1:24,000 1976
1 acre
S.C. Wildlife and Marine
Resources Department
SC2 Santee and Cooper River
Basins
Hydrology/Soils 1:24,000 1982
Vegetation
(Cowardin et al.)
to the subclass
level including
special modifiers
1-3 acre
S.C. Wildlife and Marine
Resources Dept/
U.S. Fish and Wildlife
Service
SC3 Coastal Plains
(National Wetlands
Inventory)
Hydrology/Soils 1:24,000
Vegetation 1:100,000
(Cowardin et al.)
to the class
level only
1982
1 acre
U.S. Fish and Wildlife
Service
Source: Claude Terry & Associates, Inc. 1982.
-------
LEGEND
MAY 1981
® IN PROGRESS
O LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
9 LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
• SMALL SCALE MAP AVAILABLE
© SMALL SCALE MAPS ONLY
Figure 2.3.7. Status of the National Wetlands Inventory in South Carolina,
Source: U.S. Fish and Wildlife Service. April 1982.
65
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.3 Wetland Inventories in Region IV
2.3.8 Tennessee
ONLY WETLANDS IN WEST TENNESSEE HAVE BEEN MAPPED
Several wetland mapping projects have been undertaken In
Tennessee, all located in west Tennessee (Mississippi
River Basin). West Tennessee is the only portion of the
state with extensive wetlands.
Several federal agencies have undertaken wetland mapping projects in west
Tennessee. The U.S. Geological Survey and the Tennessee Valley Authority
completed a joint wetlands mapping effort in four selected west Tennessee
sites; Reelfoot Lake, Duck River, Hatchie River Bottoms and the White Oak
Swamp. Using high-altitude, color infrared photographs, wetland areas as
small as 1 acre (0.5 ha) were mapped at a scale of 1:24,000 (Carter et al.
1979).
The Corps of Engineers (Memphis District) have mapped wetlands in the
Obion and Forked Deer River basins in west Tennessee. Using a classification
system based on timber types, these maps have also been prepared at a scale
of 1:24,000. The U.S. Fish and Wildlife Service, as part of the National
Wetlands Inventory has also completed mapping in the Mississippi River basin
in west Tennessee. Prepared at two scales (1:24,000 and 1:100,000), these
maps use the classification system specifically developed for the National
Wetlands Inventory (Cowardin et al. 1979).
Additional mapping of wetlands may have been done as part of other
comprehensive resource mapping in Tennessee. However, since these efforts
vary greatly in their detail concerning wetlands, they are not included in
this summary.
Table 2.3.8 summarizes the wetland mapping efforts to date in Tennessee.
66
-------
Table 2.3.8 Wetland Inventories in Tennessee.
Tl
Inventory Coverage
Selected areas in West
Tennessee (Reel foot
Lake, Duck River, Hatchie
River Bottoms and White
Oak Swamp)
Classification Scale Date
Vegetation/ 1:24,000 1978
hydrology
(developed for
the Tennessee
Valley Region)
Resolution Agency
1 acre U.S. Geol
Tenn. Val
ogical Survey/
ley Authority
T2 Obi on/Forked Deer
River Basins
Timber types
1:24,000 1981
U.S. Army Corps of
Engineers (Memphis
District)
en
T3 West Tennessee/
Mississippi River Basin
(National Wetlands
Inventory)
Hydrology/Soils 1:24,000
Vegetation 1:100,000
(Cowardin et al.)
to the subclass
and water regime
level.
1982
1 acre
U.S. Fish and Wildlife
Service
Source: Claude Terry & Associates, Inc. 1982.
-------
en
CO
LEGEND
MAY 1981
IN PROGRESS
LARGE SCALE DRAFT OVERLAYS OR MAPS AVAILABLE
LARGE SCALE FINAL OVERLAYS OR MAPS AVAILABLE
SMALL SCALE MAP AVAILABLE
SMALL SCALE MAPS ONLY
Figure 2.3.8. Status of the National Wetlands Inventory in Tennessee.
Sniirrp: II.S. Fish and WilHlifp Service. Aoril 1982.
-------
2.0 WETLAND DEFINITIONS AND INVENTORY
2.4 Classification System Used for EIS
A MODIFIED VERSION OF THE FWS SYSTEM IS USED FOR THIS STUDY
Many classification systems have been proposed and used
nationally and throughout Region IV. They vary from
broad, general systems to extremely complex systems. The
latter are necessary to distinguish adequately between
types and characteristics of wetlands.
As indicated by previous sections, many classification systems have been
used to delineate wetlands in the southeastern United States. The basis for
these systems varies significantly with some based on soils, others on
vegetation and still others on hydrologic regime. In attempting to select a
classification for use on wastewater management issues, several considera-
tions were assessed.
Emphasis was placed on systems used by federal agencies. Since this EIS
will ultimately lead to procedures for assessing wetlands disposal of waste-
water (if deemed appropriate), significant consideration was given to classi-
fication systems used or adopted by federal agencies, particularly EPA. EPA
has joint responsibility with the Corps of Engineers for the 404 permitting
process, so there is some rationale for using the COE system. However, while
the COE wetland typing system (Table 2.2.2) is used by some state and federal
agencies, it is based almost entirely on vegetative cover. This could be
limiting in some respects when dealing with wastewater management since soils
and hydrology are also extremely important.
Circular #39 describes the system that has been used by the FWS since
1956 and was based on the system proposed by Martin et al. (1953). This
system has many advantages since it is easy to understand and classifies
wetlands in common terms. But again the system has some limitations for
wastewater management, particularly due to lack of differentiation between
significantly different wetland ecosystems.
Another classification system that has been widely used was proposed by
Penfound (1952). Though not adopted by federal agencies, it has been used by
state agencies and as a basis for other classification work.
Based on information gathered during Phase I, it appears that EPA will be
utilizing the classification system adopted by the Fish and Wildlife Service
(Cowardin et al. 1979). This system is b*ing used for the National Wetlands
Inventory conducted by FWS. Other agencies are adopting this system as well.
In assessing the applicability of this system to wastewater management deci-
sions, it has been evaluated as the system most appropriate for use. The two
major reasons for selection are: 1) it incorporates wetland characteristics
that are important to wastewater management decisions (e.g., vegetation,
hydrology, soils); and 2) EPA and other agencies are moving to adopt it.
Some modifications or clarifiers are being incorporated into the system
tor application to this EIS. The major limitations of the new FWS system
relate to its complexity. Without direct training with the system, it is
69
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2.4 Continued
difficult to understand and apply and is therefore limited in its usefulness
to people who have not been trained. Scale problems have also been encoun-
tered since the scale used often precludes small wetlands. In an effort to
enhance the understanding and applicability of the system, the matrix shown
by Table 2.4 has incorporated common terminology and dominant assemblages.
The characteristic flora listed in Table 2.4 were compiled by the U. S. Fish
and Wildlife Service, Region IV based on common wetland types identified.
Several important modifiers such as water regime, water chemistry and soils
provide further differentiation of wetland types and should be ultimately
incorporated as the system is used.
Because hydrology is an overriding factor which defines the character of
many wetland elements, two basic conditions (hydrologically isolated and
hydro!ogically open) are used to group wetland types. Some wetlands may fall
into both categories, depending on locations. Those wetlands with only
intermittent connections with other water bodies are grouped as
hydrologically isolated systems.
The matrix provided, however, attempts to indicate how common wetlands
terminology such as bogs, swamps, and marshes correlate to FWS terminology
such as Palustrine evergreen needle-leaved wetland. This is an important key
to understanding and using the FWS system. Secondly, the concept of
predominant assemblages has been incorporated to relate common and FWS terms
to typical vegetation types within Region IV. This should help identify the
proper FWS term, since most systems are primarily recognized by their
predominant vegetation type.
The proposed EIS classification system should provide sufficient detail
to classify and evaluate a wetland system properly and yet allow use by a
wide range of engineers and planners. For example, if a system is commonly
known to be a cattail marsh, it can properly be keyed into the FWS
classification as a palustrine emergent wetland. Then, through the
identification of other key modifiers, the system can be properly defined and
evaluated. The concept of hydrologically isolated and hydrologically open
provide a starting point for evaluation of wetlands for wastewater
management.
70
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Table 2.4. Wetland EIS Classification Matrix.
Common Wetland Types
National Wetlands Inventory
Hydrologically Isolated S-stem
(Fish and Wildlife Service) Characteristic Flora
System Type Class ~Subclass"Common name (Botanical name)
Wooded swamp*
Palustrine Forested wetland
Broad-leaved
deciduous
Cypress dome
Bog, pocosin, Carolina
bay, evergreen shruL-
bog, bay head
Shrub swamp
Pine flatwoods, pine
swamp
Shallow freshwater
marsh, deep freshwater
marsh, inland marsh,
bogue, prairie, savannah
Palustrine Forested wetland
Palustrine Scrub-shrub
wetland
Paulstrine Scrub-shrub
wetland
Palustrine Forested
wetland
Palustrine Emergent
wetland
Needle-leaved
deciduous
Broad-leaved
deciduous
Broad-leaved
deciduous
Needle-leaved
evergreen
Persistent;
non-persistent
Water tupelo (Nyssa aquatica); swamp black gum (N. biflora);
Ogeechee plum (N. ogeche); water elm (Planera aquatica);
water, Carolina ash (Fraxinus caroliniana); bald cypress (Taxo-
dium distichum); fetter bush (Lyonia TucTda); leatherbush,
titi (Cyrilla Vacemiflora); common alder (Alnus serrulata); wax
myrtleWrTca cerifera); black willow (Salix nigra); buttonbush
(Cephalanthus occidentalis); Virginia willow (Itea virginica);
overcup oak (QueVcus lyraTa); red maple (Acer rubrum var. drummondii)
Bald cypress (Taxodium distichum); pond cypress (T. ascendens)
Leatherbush, titi (Cyrilla racemiflora); fetterbush (Lyonia lucida);
inkberry, holly (Ilex glabra); Zenobia (Zenobia pulverulentail
pond pine (Plnus serotina); red maple (Acer rubrum); bay, bay
magnolia, white bay (Magnolia virginiana); loblolly bay (Gordonia
lasianthus); southern white cedar (Cnama'ecyparis thyoides); swamp
bay (Persia borbonia); wax myrtle (Myrica cerifera); pepperbush
(Clethra alnifolia)
Common alder (Alnus serrulata); swamp privet (Forestiera acuminata);
black willow (Salix "nTgra); buttonbush (Cephalanthus occidentalis);
Carolina willow (S7 caroliniana); Virginia willow (Itea virginica)
Pond pine (Pinus serotina); loblolly pine (P. taeda); slash pine
(P. ellipttil); longleaf pine (P. palustrisTT wax myrtle (Myrica
cerifera); titi, leatherbush, (Cyrilla racemiflora)
Cattail (Typha spp.); bulrush (Scirpus spp.); maidencane
(Panicum heini toman); lizards tail (Saururus cernuus);
alUgatorweed (AUernanthera philoxirpides); sedge (Carex spp.,
Cyperus spp., Rhynchospora spp.); rush (JUncus spp.. Eleocharis
spp.); reed (Arundo donax, Phragmites communls); aster (Aster);
beggartick, stick-tight (BlTJfens spp.); water hemlock (Clcuta
maculata); sawgrass (Cladium JaTmaicense); barnyard grass
(Echinochloa crusagalli); splkerush (Elepcharis spp.); joe-pye
weed, late boneset (Eupatorium spp.), mallow (Hibiscus spp.); Iris
(Iris virginica, Iris spp.); purslane (Ludwigla spp.); maidencane,
switchgrass (Panicum spp.); joint grass (Paspalum distichum);
pelandra (Peltandra virginica); smartweed (Polygonum spp.);
pickeralweed (Pontederia cordata); arrowhead (Saglttaria spp.)
*May also be hydrologically open system
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Table 2.4. Continued
Common Wetland Types
National Wetlands Inventory
(Fish and Wildlife Service)
System Type Class
Savannah, wet prairie
Palustrine
Emergent
wetland
Meadow, wet meadow
fresh meadow
Palustrine Emergent
wetland
Hydrologically Open Wetl. nds
Marsh, bayou, brake,
ox-bow, swamp creek,
flat, prairie-marsh,
slough
Palustrine
Lacustrine
Riverine
Aquatic bed
Mixed bottomland
hardwood, hardwood
strand
Marsh
Cypress Strand
Palustrine Forested
Riverine Emergent
Lacustrine wetland
Palustrine Forested
wetland
Subclass
Persistent;
non-persistent
dependent on
dominants
Characteristic Flora
~Co~mmon name (Botanical
name)
Persistent;
Non-persistent
(dependent on
dominant)
Various;
dependent on
dominants
Grass -pink (Calopogon spp.); coastal milkweed (Asclepias spp.);
pitcher plant (Sarracenia spp.); St. Johns' wort (HyperTcum spp.)
toothache grass (Ctenium spp.); club-moss (Lycopodium prostratum);
bog-button (Lachnocaula anceps); sea pinks (Sabatia spp.);
yellow-eyed grass (Xyris spp.); meadow-beauty (Rhelia spp.); marsh
fleabane (Pluchea spp . ) ; muhly (Muhlenbergia spp.); Aristida spp.;
lobelia (Lobelia spp.); nutrush (Sclerla spp.); sun dew (Drosera
spp.); Pagonla spp.; milkwort (Polygala lutea); pipewort (Eriocaulon
spp.); bog-orchid (Habeneria SPP.): sedge (Dichromena spp.")
Broad-leaved
deciduous
Persistent;
non-persistent
(dependent on
dominants)
Needle-leaved
deciduous
(Cyperus spp.); rush (Juncus spp.);
ge (Rhynchospora spp.) tickweed, beggartick, stick-tight
(Bidens spp.); aster (Aster spp.); goldenrod (Solidago spp.); joint-
grass, para grass (Panicum spp.); broom straw (Andropogon spp.)
Sedge (Carex spp.); flat sedge
beaked sedge
Watershield (Brasenia schreberi); fanwort, cabomba (Cabomba
caroliniana); hornwort (Ceratophylum spp.); water hyacinth
(EichorniT'crassipes); El odea spp.; duckweed (Lemna spp.); penny-
wort (Hydfocotyle spp.); southern niad (Najas spp.); lotus (Nelumbo
lutea); spatterdock (Nuphar advena); white water lily (Nymphaea
oderata); pondweed (Potomogeton spp.); duckmeat (Spirodela poly-
rrhiza); bladderwort (Utricularia spp.); sa1vinia(Sa1vinia
auriculata); mosquito fern (Azolla caroliniana)
Laurel oak (Quercus laurifolia); willow oak (Q. phellos); swamp
chestnut (Q. michauxii); cherry bark oak, swamp Spanish oak (Q.
pagoda); loElolly pine (P. taeda); American white elm (Ulmus americana);
sweet gum (Liquidambar styraciflua); river birch (Betula nigra); ir
wood, blue beech (Carpinus caroliniana); palmetto, dwarf palmetto
(Sabel minor); cabbage palm (Sabel palmetto)
Lizards tail (Saururus cernuus); alligator weed (Alternanthera
philoxeroides); sedge (Eleocharis spp.); iris (Iris virginica);
pelandera (PeUandra virginlca); smartweed (Polygonum spp.);
pickeral weed (Pont¥deria cprdata); wild rice (ZlzanTa spp.);
bulrush (Sdrpus spp.); rush (Juncus spp.)
Bald cypress (Taxodium distichum);*pond cypress (T. ascendens)
i ron-
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SECTION 3
PROFILE OF EXISTING WETLANDS DISCHARGES
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3.0 PROFILE OF EXISTING WETLAND DISCHARGES
A PROFILE OF EXISTING WETLAND DISCHARGES FOR REGION IV WAS
ACCOMPLISHED THROUGH AN INFORMATION SURVEY PROGRAM
An Inventory was conducted to obtain Information from
existing wetlands dischargers. Information obtained
relates to land ownership, effluent characteristics,
discharge frequency and duration, monitoring programs and
identifiable problems.
The physical and biological characteristics of wetland ecosystems vary
greatly between states in Region IV. To provide a better understanding of
how wetland systems differ among states, an inventory and analysis of
existing wetlands discharges was conducted for Alabama, Florida, Georgia,
Mississippi, North Carolina, South Carolina and Tennessee. Kentucky has not,
at this time, identified wastewater discharges to wetlands.
A list of existing wetland dischargers was obtained from the appropriate
department in each state. A survey form (Table 3.0-a) was then sent to each
discharger. The wetlands profile for each state was based on questionnaires
received from dischargers who responded. Table 3.0-b gives the total number
of wetlands discharges included in the survey by state and the number of
respondents. An attempt was made to contact those dischargers in each state
who did not respond so that a complete wetland discharge profile for each
state could be presented. Information received from the surveyed wetland
dischargers is discussed in the following subsections.
Field trips were also conducted through each of the seven states with
identified wetlands discharges. These site visits were used to provide
first-hand knowledge of selected wetland discharges and provide a greater
understanding of the wetland systems in each state. In early April a trip
was taken through south Georgia and Florida. In early June a field trip was
taken through Alabama, Mississippi and west Tennessee while a second study
team visited the coastal plain of South Carolina and North Carolina.
Summaries of these site visits are included in the following subsections.
Issues of Interest
0 What are the predominant wetland systems used for wastewater management
in each of the EPA Region IV states?
• How many wetland discharges have been identified in EPA Region IV?
• What are the major characteristics of wetland discharges in EPA Region
IV?
73
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Table 3.0-a. Information Form Sent to Existing Wetland Dischargers in
Region IV.
WETLANDS DISCHARGE SURVEY
CLAUDE TERRY & ASSOCIATES, INC., ATLANTA, GEORGIA
Name:
NPDES Permit No.:
Discharge Source:
Would you like to be included on our mailing list to follow the progress of
this study? yes no
1. Please describe the type and approximate area of the system you discharge
to (e.g., river swamp, creek, swamp creek, cypress dome, etc.). Include a
general description of the vegetation (e.g., cattails, hardwoods, etc.) and
other uses.
2. Do you own this area? yes no
Do you have an easement to discharge to this area? yes no
3. How long have you been discharging into this water body? What is the
frequency of discharge (daily, weekly, continuous, etc.)?
4. What changes in the receiving waters have you detected since you've been
discharging (e.g., loss of vegetation, algae blooms, increased vegetation,
rise in water level, etc.)?
5. What problems have you experienced relating to the discharge (e.g.,
citizen complaints, legal questions, regulatory difficulties, etc.)?
74
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Table 3.0-a. Continued
6. What type of treatment system and backup system, if any, do you have?
What type of disinfection?
7. Please describe your in-stream monitoring program, if any.
8. What type of effluent do you discharge (e.g., industrial, domestic,
cooling water), and what is the average effluent flow?
9. What are your effluent characteristics?
BOD5 pH
NH3 Total Nitrogen
Dissolved Oxygen Total Phosphorus
Temperature Industrial Components
Total Suspended Solids
Composite sample frequency
Grab sample frequency
Other (please describe)
10. In your opinion, are wetlands useful for wastewater treatment and/or
disposal? What could be done to improve or enhance this use of wetlands?
75
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Table 3.0-b. Total Number of Surveyed Wetlands Discharges by State and the
Number of Respondents.
State
Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina*
South Carolina
Tennessee
Wetlands Discharges
13
58
10
-
40
61
34
12
Number of Respondents
8
30
3
-
13
21
22
8
*North Carolina listed 267 discharges to "swamp waters." The 61 in this
table are discharges greater than 0.1 mgd that discharge directly to
wetlands.
Source: Claude Terry & Associates, Inc. 1982.
76
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3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.1 Alabama
SWAMP CREEKS WITH HARDWOODS REPRESENT THE PREDOMINANT WETLAND
DISCHARGE IN ALABAMA
Alabama has 13 Identified wetland discharges, most of
which have been in operation for many years. Few
dischargers have indicated any significant impacts or
problems. Several survey respondents stressed that
wetlands are useful only with adequate wastewater
treatment. Four discharge sites in the central portion of
the state were visited in early June.
A list of 13 wetland dischargers was obtained from the Alabama Water
Improvement Commission (AWIC). These sites (10 municipalities; 3 industries)
were identified based on the knowledge of the AWIC staff. The profile of
existing dischargers in Alabama is based on eight survey responses and four
site visits.
Based on the survey responses, most wetland dischargers dispose treated
effluent into swamp creeks. Bottomland hardwoods and mixed hardwoods/pines
are the predominant vegetation types surrounding these wetlands. Cattails
and cypress were also identified at several Alabama discharge sites. All
discharges were described as continuous with the period of discharge ranging
from two years to 40 years (average: 18 years).
Few impacts or problems were identified by any of the wetland discharg-
ers; two respondents noted increased vegetation while one respondant cited a
pending lawsuit from an adjacent property owner (the legal issue was not
elaborated). Most effluent was derived from domestic sources. Opinions were
mixed concerning the use of wetlands for treatment or disposal with several
respondents highlighting the need for adequate wastewater treatment and
precautionary measures prior to discharging to wetlands.
Four municipal discharge sites located in the central portion of the
state were selected for site visits in early June, 1982. These four
discharge sites were highly channelized, forested streams, but local sources
indicated that these discharges may enter typical wetlands at a distance
farther from the discharge point. The following narratives describe the
field conditions observed during the site investigations.
Auburn, AL. The Director of Public Works for the City of Auburn provided
information concerning the two wastewater treatment plants serving the city.
The northside plant discharges approximately 1.0 nigd to Sagahatchee Creek.
No obvious odor problems were noticeable 1/4 mile from the discharge point.
Although this plant was operating beyond design capacity, the trickling
filter and clarifiers were producing an effluent of reasonable quality. The
creek bed was composed of granite and clay. Sagahatchee Creek near the
discharge point was highly channelized and forested with honeylocust and
bahx SPP- and did not appear to be a continuous wetland. It is possible
that this creek drains into a wetland five to ten miles downstream but this
was not verified.
77
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3.1 Continued
The southside treatment plant discharges approximately 4.0 mgd to Parkers
Mill Creek. Topographic maps indicate a wetland area exists one to two miles
south of the discharge point. Local sources contend that this is a seasonal
wetland and the stream generally remains channelized. Water quality studies
by Dr. Joe Morgan (Auburn University Department of Civil Engineering) suggest
that a significant amount of nitrification occurs along the length of Parkers
Mill Creek. Measurements indicate that dissolved oxygen is at or near back-
ground levels (2-4 mg/1) at the Parkers Mill Creek confluence with Chewakla
Creek. Chewakla Creek enters a large, permanently forested wetland in Macon
County, Alabama, about five miles further south.
Tuskegee. AL. The moderately sized, extended aeration wastewater treat-
ment plant at Tuskegee, Alabama discharges approximately 1.25 mgd to Calebee
Creek, contributing approximately 5-10 percent to the total stream flow.
Recent rains had raised this highly channelized creek four to six feet in the
few days proceeding the site visit. The terrain at Calebee Creek was flatter
than at Auburn and the soils were sandy in contrast to the clay and granite
soils found near Auburn. The immediate discharge area was not a riverine
wetland, but local sources acknowledge that the creek may enter a large swamp
in the Tuskegee National Forest, five to ten miles downstream.
Union Springs. AL. The Water Superintendent for the City of Union
Springs indicated there is no direct discharge to wetlands from either of the
two wastewater treatment plants serving Union Springs. He was also unaware
of any wetland areas downstream of the discharge plants.
Uniontown, AL. The Mayor of Uniontown provided information concerning
the two sewage lagoons "which provide treatment (no chlorination) for approx-
imately 0.05 mgd of wastewater. The receiving creek was well-channelized at
the time of the site visit but prone to flooding several times a year. The
predominant vegetation along the creek was Salix spp., but this creek would
not be classified as a wetland. The stream may enter a wetland area down-
stream but this was not verified. Industrial discharges reportedly cause
periodic water quality problems (odors, algae blooms) along the stream
course.
78
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Table 3.1. The Profile of Wetlands Discharges Based on Questionnaire Response for Alabama.
--J
10
Discharge Wetland
Number Type
1
2
3
4
5
6
7
8
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Creek
Creek
Swamp creek
Creek
Typical
Vegetation
Hardwoods,
pines, thick
underbrush
Pine, hard-
woods ,
pasture
Time Since
Easement or Discharge
Ownership Began
Easement 30 years
Ownership 40 years
Oaks, hickory Easement 25 years
pine, cattails
Hardwoods
Hardwoods
Mixed pine/
hardwoods
-
Hardwoods,
/*unpoc c
cypress
Easement 6 years
Ownership 14 years
22 years
2 years
Ownership 4 years
Discharge
Frequency
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
"*
Wetlands
Impacts
None
Improved
water quali-
ty (effluent
is 5 times
creek flow)
Increased
vegetation
None
Increased
vegetation
Sedimenta-
tion of
stream
None
None
Discharge
Related
Problems
Infrequent
odor and
color
problems
Flooding,
outfall
backup
Regulatory
difficul-
ties, citi-
zen complaints
None
None
Lawsuit by
adjacent
property
owner
None
None
Effluent Type
and Average
Daily Flow
Domestic
Domestic
(60%)
3.0 mgd
Domestic/
Industrial
.589 mgd
Domestic
1.25 mgd
Domestic/
Industrial
.35 mgd
Domestic
.375 mgd
Industrial
Domestic/
Industrial
.003 mgd
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
Wetlands are useful only
proper treatment
wi
Useful for wastewater treat
Useful for wastewater
disposal
Not useful for treatment;
could be used for disposal
Permit provisions need to :
adopted to allow wetlands
for treatment
-
Could be useful for treatmer
Source: Survey of wetland dischargers conducted by Claude Terry & Associates, Inc., Spring 1982.
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3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.2 Florida
CYPRESS DOMES AND SWAMP CREEKS DESCRIBE THE MAJOR WETLAND
DISCHARGE TYPES IN FLORIDA
Florida has 58 identified wetland discharges. Several
have been in operation for many years. Most respondents
believe wetlands are useful for wastewater treatment and
disposal.
A list of 54 wetlands dischargers was obtained from the Florida Depart-
ment of Environmental Regulation, Bureau of Water Analysis. The list was
compiled from a newly created data base system, and some areas in the state
had not stored pertinent information into the system at the time of data
retrieval. Because of this, some existing wetland discharge areas may not be
represented in the final list. Subsequently, four additional wetland dis-
charges were identified by the Florida DER Southwest District bringing the
total of identified wetland discharges to 58. The profile of existing
wetlands in Florida is based on 30 responses. Fifteen responses were the
result of the survey and 15 additional responses were provided by the
district offices of Florida DER. Fifteen negative responses indicating
non-wetland or discontinued discharges were also received, bringing the total
response rate to nearly 78 percent. Many of the responses prepared by
Florida DER, however, provided inadequate information.
A variety of wetland ecosystems in Florida are used as disposal sites for
treated wastewater. Cypress domes, swamp creeks and marshes represent the
most common wetlands used. These areas are vegetated with cypress, swamp
maple, water oak, sawgrass, cattails, hyacinth and a diversity of weeds. The
discharge areas are owned in 11 instances with the remaining respondents
using easement rights to discharge. The frequency of discharge ranged from
continuous in 19 areas to monthly in one area. Based on 25 responses, the
average period of discharge is 22 years with a range from less than one year
to 90 years.
Increased vegetation and water quality degradation were typical problems
relating to changes in receiving water. Regulatory problems associated with
discharging were indicated in seven areas. A variety of effluent is dis-
charged into Florida wetlands. Most effluent is domestic, but there are sev-
eral industrial and cooling water sites as well as one site that discharges
stormwater. The minimum and the maximum daily effluent flows for 11 sites
are 0.0005 mgd and 5.0 mgd, respectively. The respondents, as a majority,
felt wetlands are useful for wastewater treatment and disposal. Table 3.2
profiles existing wetlands in Florida based on the survey responses and
information from Florida DER.
A field trip to north and central Florida was conducted to examine the
various types of wetlands discharges found in Florida. Nine discharges were
visited and are summarized below.
80
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3.2 Continued
Royal Lakes (Jacksonville), FL. The Royal Lakes treatment plant,
originally serving the Royal Lakes subdivision but now serving as a regional
plant, discharges to a forest swamp. The tour was conducted with the
operator and the district engineers of the Jacksonville Suburban Utilities
Corp. After secondary treatment the effluent is discharged to a canal which
flows under a highway and into the swamp. Emergent and floating vegetation
were observed in the canal. This discharge, as with several others in
Florida, was the subject of another study; therefore, additional information
is available for this site. One interesting aspect of this site was at a
location where water from the swamp downstream of the effluent combined with
water from a part of the swamp undergoing development. The latter was
extremely sediment laden whereas the former showed no evidence of increased
solids or vegetation associated with wastewater (duckweed).
Deerwood Subdivision (Jacksonville), FL. This wastewater treatment
facility serves a large subdivision. After treatment in aerators, the
effluent is discharged to a lagoon from which it is discharged to a canal
that leads to a forest swamp. The swamp system was not investigated.
Lake Buena Vista, FL. The wastewater treatment system at Walt Disney
World is one of the most innovative and sophisticated systems in operation.
After undergoing a high degree of secondary treatment, effluent is disposed
of by three different methods. An experimental artificial wetland system
using water hyacinths is being studied for potential application. The major
portion of the effluent from the plant (<5 mgd) is discharged into a cypress
strand. Another portion is used for spray irrigation and the third portion
combines percolation ponds with overland flow through a cattail marsh. This
effluent, and that from the strand, ultimately discharge to the Reedy Creek
system. A tour of the facilities was provided by a representative of the
Reedy Creek Improvement District. This system appears to operate effectively
but is land intensive.
Clermont, FL. The wastewater facility at Clermont, Florida, has also
been researched by the University of Florida. At the time of research the
discharge was to a marsh system. However, this has since been discontinued
and discharge is now achieved via spray irrigation. The treatment system can
still be considered to include wetlands since one of the three lagoons used
for polishing after typical secondary treatment processes has become a
volunteer wetland with extensive and varied emergent and subemergent
vegetation. Wildlife is prolific in and around the polishing lagoons. Also,
due to probable groundwater movements, water discharged by spray irrigation
eventually leaches to the marsh system used for the research project.
Uildwood, FL. The discharge from Wildwood, Florida, is one of the most
well established and oldest wetland discharges. After receiving secondary
treatment the effluent is discharged to a canal which typically discharges to
a swamp. No visible stress or damage to natural systems is evident. How-
ever, under severe flow conditions the effluent may migrate to a shallow lake
that is characterized by extensive emergent, submergent and floating
vegetation.
81
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3.2 Continued
Gainesville, FL. The wastewater discharge at the Whitney Trailer Park in
Gainesville, Florida, was the subject of a long-term study on the effects of
wastewater disposed in cypress domes. A series of domes and strands were
used. Two domes received wastewater effluent and one dome received ground-
water only. The Austin Carey cypress swamp was used as control for these
experiments. The effluent from the trailer park was treated in a package
plant/oxidation pond system prior to discharge to the domes. This system was
discontinued in early 1981 but generated much of the information gathered on
the impacts of wastewater on cypress dome systems.
Waldo, FL. The city of Waldo, Florida, has been discharging primary
effluent to a cypress/hardwood swamp for several years. After passing
through an Imhoff tank, the wastewater travels through a canal to the swamp.
This site has also been the subject of research by the University of Florida.
Nutrient cycling, the fate of heavy metals and pathogenic microbes discharged
to the swamp have been studied but final results are not yet available.
Lake City. FL. Of several wetlands discharges found in the area, the
system visited was the Holiday Inn on 1-75. This motel discharges to a
cypress dome from a package plant operated by the motel. The operator pro-
vided a tour of the facilities. This site provided the best example of a
stressed system since many of the cypress were dead. However, this was not
related to the wastewater effluent but to a backwashing of salts which
occurred in the mid-1970's from the motel's water softening operation
(according to the current operator). The area currently receiving effluent
showed only the signs of increased duckweed populations.
Jasper, FL. As with several of the other visited discharges, the Jasper,
Florida, site has been the object of extensive research. The system is com-
posed of secondary treatment processes with two polishing ponds. The
effluent moves from the second pond into a marsh-swamp system with cattails
and cypress. The cypress in this system were visibly stressed. The cause or
causes are not fully understood but two explanations prevail: one, that the
primary effluent discharged for many years overloaded the system; two, that a
gasoline overflow from a nearby gasoline station (upgradient) impacted the
strand. The prevailing explanations do not indicate that the secondary
effluent has caused the observed problems.
82
-------
Table 3,2. The Profile of Wetlands Discharges Based on Questionnaire Response for Florida.
CO
Discharge Wetland
Number Type
*1
*4
Swamp creek
2 Forested
swamp
3 Cypress
swamp
Marsh
Marsh
Swamp
Swamp
One mile
through
grassed ditch
to private lake
Typical
Vegetation
Cypress,
hardwood
Swamp maple,
bay, gum,
water oak
Cypress
"
Sawgrass
Pines, weeds
Hyacinth
and cattail
lime bince
Easement or Discharge Discharge
Ownership Began Frequency
Easement
Ownership 90 years Continuous
Ownership 3.5 years
Ownership 12 years Daily
Ownership 18 years Continuous
Ownership 23 years Continuous
Easement 24 years Continuous
Ownership 9 years Continuous
Discharge Effluent Type
Wetlands Related and Average
Impacts Problems Daily Flow
None None Domestic
0.4 mgd
None None Industrial
3.5 mgd
Increase none
in phos- - 3.3 mgd
phate
None State of FL Domestic
& local 0.0005 mgd
pollution
control board
do not accept
marshland
disposal
methods
Water None Cooling water
level o.09 mgd
changes due
to seasonal
operations
None None Domestic 75%,
cooling water
25%
0.275 mgd
Regulatory Domestic
difficulties 0.275 mgd
Increased None Industrial
vegetation 0.005 mgd
Are Wetlands Useful
for Wastewater Treatment
And/or Disposal
Yes
Wetland discharge is our
only viable option.
Wetlands overflow discharge
is effective.
Wetlands disposal is only
practical solution in much
of central Florida.
Many large swamps in the
area could be used for
effluent disposal.
Yes
-------
Table 3.2. Continued
Discharge Wetland Typical
Number Type Vegetation
Time Since Discharge Effluent Type
Easement or Discharge Discharge Wetlands Related and Average
Ownership Began Frequency Impacts Problems Daily Flow
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
Wetland
* 10 Wetland
11 Swamp
oo
Pumpkin ash, Easement
maple, black-
gum, sweetgum,
bald cypress,
yellow poplar,
swamp bay, wax
myrtle, oak,
magnolia, holly,
peterbush, cabbage
palm, Virginia
wi11ow
12 years Continuous
Cypress,
hardwood,
cattail
Easement
Easement
66 years
25 years Continuous
12 Cypress dome Cypress, Easement 37 years Monthly
swamp algae
13 Prairie basin Cypress Easement 62 years
None Regulatory Domestic
difficulties -
Increased Collection
vegetation system has
problems
None
None
Regulatory
problems
engendered
by unrealis-
tic attitude
of EPA
EPA said
dissolved
oxygen prob-
lems exist
Domestic
0.221 mgd
Cooling water
Rainwater
Effluent
may have
caused an
increase
in algae,
but other
nonpoi nt
sources of
pollution
exist.
Regulatory Domestic
mandates to 2.0 mgd
remove all
effluent sites
from lake
basin. Nu-
trient loads
In lake ex-
ceed permis-
ible load which
is 0 nitrogen
and 0 phospho-
rus. Groundwater
pollution also
occurs
Wetlands are useful; should
be responsible
monitoring.
Wetlands are very useful
if not overloaded.
Yes. Our understanding is
that wetlands operate
naturally as cleaning areas
and should be allowed to
continue, bearing in mind
natural characteristics.
No opinion
Yes. A full environmental
assessment should be made
to evaluate wetlands' cap-
abilities to accept discharge.
-------
Table 3.2. Continued.
00
On
Number
14
15
16
17
18
19
20
21
22
23
25
3e Wetland
Type
Swamp
Swamp creek
Swamp creek
Creek
Canal
Drainage
Swamp
Cypress swamp
Swamp
Swamp
Cypress dome
River swamp
lime Since
Typical Easement or Discharge
Vegetation Ownership Began
Cypress - 72 years
Cattails, Ownership 17 years
hyacinth,
other aquatic
vegetation
Cypress, Ownership 1 year
cattails
-
-
8 years
-
Cypress,
bottomland
hardwoods
11 years
None 10 years
Cypress - 1 year
Ownership 6 months
Discharge
Frequency
Continuous
Continuous
Continuous
Continuous
-
Intermittent
-
Continuous
Continuous
Continuous
Intermittent
.
Wetlands
Impacts
Water
quality
impacts
Increased
vegetation
Increased
vegetation
-
Loss of
forests
_
-
-
-
_
_
Discharge Effluent Type Are Wetlands Useful
Related and Average for Wastewater Treatment
Problems Daily Flow and/or Disposal
Some cypress Industrial
trees have and domestic
died, but 0.45 mgd
exact cause
is not known.
None Water from In some cases wetlands are
clay settling useful. The degree of use
areas fulness would need to
5.0 mgd be evaluated in
each case.
None Non-contact Yes
cooling water
Industrial
Legal Industrial
questions
and regula-
tory problems
Industrial
.0072 mgd
Domestic
Unable to Domestic
harvest
timber
Domestic
Fish kill Cooling
molasses water
dump (1979)
Bad odors, Laundry
potential wastewater
problems .0042 mgd
Depressed Citrus
D.O. wastes
-------
Table 3.2. Continued
Discharge Wetland Typical Easement or Di^rae* Dlwharoi. u ti A "T^96 Effluent Type Are Wetlands Useful
Number lm Vegetation Ownership Bean F™?! ?"™'S 2e.!«*!l and Average for "—~ r~..
co
26
River swamp
uwnersnip Began Frequency Impacts
5 years Continuous
P roblems
Permit
Dally Flow And/or Disposal
Domestic
noncompliance
27
Swamp
Ownership 10 years Continuous
Permit
Domestic
noncompliance
28
29
30
Swamp
Swamp
River swamp
Easement 6 years Continuous
Easement 6 years Continuous None
Ownership 8 years Continuous None
None
None
Permit
violations
Domestic
(AWT)
1.3 mgd
Domestic
(AWT)
.844 mgd
Domestic
.818 mgd
S°UrCe: F^a°DfER"Bdt!;tnHc?oCfh?K" ^^ * """* ^ & *««'**• Inc- ^"* ^> supplanted by
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.3 Georgia
DISCHARGES TO INTERMITTENT AND SEASONAL WETLANDS
ARE IDENTIFIED IN GEORGIA
Responses from a limited number of surveyed discharges
provided Information which Indicates discharges are made
to Intermittent streams and seasonal wetlands. Responses
from continuous, long term discharges Identified few docu-
mented problems.
A list of 10 wetland discharges was provided by the Georgia Environmental
Protection Division, Water Protection Branch. This list included eight muni-
cipal discharges and two industrial discharges. Additional wetland dis-
charges may be permitted in Georgia but have not been identified as wetland
discharges by the staff of Georgia EPD. Of the 10 dischargers surveyed, only
three municipalities responded.
Information provided by the three dischargers indicated discharges to
drainage canals or possibly intermittent streams which drain directly into
wetland areas. Vegetation near the discharge sites include pines, mixed hard-
woods, cypress and cattails. These three discharges have been relatively
long-term and continuous. Two of the dischargers recognized a rise in water
level with varying impacts on vegetation. Permit violations and high BOD
loadings were cited as problems. These discharges consisted of domestic or
combined domestic/industrial discharges. Specific information for these
three dischargers is provided in Table 3.3.
A field trip through the south coastal plain of Georgia was conducted in
early April 1982, in order to supplement the survey responses. The dis-
charges of five communities were examined.
Cochran, GA. This discharge was typical of many observed in south
Georgia. The wastewater was treated to secondary levels and then discharged
into a swamp creek with a relatively low flow. The stream flowed through
sandy soils with hardwoods and some cypress and was characterized by high
organic color.
Alapaha, GA. After treatment via oxidation pond, the discharge entered a
small channel that cut through low lying lands before entering the floodplain
of the Alapaha River. The discharge stayed within the discharge channel for
approximately one mile before spreading over the floodplain as sheetflow.
The only evidence of this discharge was highly organic sediments within the
channel and along its banks.
Pearson, GA. The Pearson, Georgia, wastewater treatment plant used a
brush aerator system to provide secondary treatment. The wastewater moved
through clarifiers and a contact chamber prior to discharge into a bottomland
hardwood swamp. The effluent traveled through a pipeline approximately 50
meters long into the swamp, which had no discernable channel. The chief
operator of the plant indicated that the direction of flow within the swamp
was variable and the actual size, area of influence, and detention times were
87
-------
3.3 Continued
unknown. No visible stress on the system was evident, however large
quantities of duckweed were observed in the swamp.
Hahira, GA. The discharge from the Hahira, Georgia, treatment facility
was similar to that at Cochran. The receiving water was an organic-colored
swamp creek with low flows. Such systems appear to stay in their channels
under most conditions, with overflow occuring only during flood conditions.
No visible signs of damage or stress to the vegetation was evident.
Camilla, GA. Of the several discharges examined, this was the only
system which should probably not be considered a wetlands discharge.
Although it ultimately discharged to a forest swamp, the wastewater travelled
through a well-defined, non-vegetated channel for two to three miles. The
impacts on the swamp from this discharge had not been examined to determine
the degree of influence on the swamp or the extent of treatment achieved
within the channel. The water quality was visibly poor within the channel.
The situation in Camilla is important as it reflects the problems associated
with determining what is or is not a wetlands discharge. What may be
classified a wetlands discharge in one Region IV state may not be classified
a wetlands discharge in another Region IV state.
88
-------
Table 3.3. The Profile of Wetlands Discharges Based on Questionnaire Response for Georgia.
Discharge Wetland
Number Type
1 Drainage
canal
Creek
3 Drainage
canal to
creek
Typical
Vegetation
Pines, oaks Easement
myrtle buses
Easement
cattails, Easement
tupelo
CO
nme bince
or Discharge
3 Beqan
15 years
)/ 25 years
•/ 25 years
Discharge
Frequency
Continuous
Continuous
Continuous
Discharge
Wetlands Related
Impacts Problems
Rise in Regulatory
water problems,
level, permit
decreased violation
fish pop-
ulation
Loss of High BOD
vegetation, loading
Increased
algae growth
Increased None
vegetation
rise in
Effluent Type
and Average
Daily Flow
Domestic
1.6 mgd
Domestic/
Industrial
Domestic/
cooling water
.65 mgd
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
No. Need a year round
flow source. Wetland
operations are more
expensive
Yes, with adequate aeration
Yes, should use more
drainage ditches and canals
water level
Source: Survey of wetland dischargers conducted by Claude Terry & Associates, Inc., Spring 1982.
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.4 Kentucky
KENTUCKY DOES NOT HAVE ANY PERMITTED WETLANDS DISCHARGES
Although Kentucky contains wetlands in various parts of
the state, no permitted discharges to wetlands exist.
However, some discharges to wetlands occur from coal
mining operations.
The Kentucky Department for Natural Resources and Environmental
Protection, Bureau of Environmental Protection, indicated that there is no
provision in the Kentucky water quality standards for the specific
classification of wetlands. Although wetlands exist in Kentucky the state
does not have a list of wetlands dischargers because no NPDES permit
applications or permit issuances exist for wastewater "**'"&**«
As a result, a profile of wetlands discharges in Kentucky was not feasible.
Kentucky has, however, identified wetland water quality ^
association with certain coal mining operations. In some *
western Kentucky, wetlands have been impacted by "onpoint runoff
mining operations, discharges from sedimentation and silt structures, and
acid mine drain from abandoned mines. Discharges associated with coa mining
operations may require NPDES permits; however, this type of wetland discharge
is outside the scope of this EIS and has not been further evaluated.
90
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.5 Mississippi
BAYOUS REPRESENT THE WETLAND TYPE IN MISSISSIPPI MOST FREQUENTLY
USED FOR EFFLUENT DISPOSAL
Although only 13 positive responses were received from 40
Identified wetlands discharges, useful Information was
obtained. Bayous and sloughs are the common wetland types
used for discharges. Odor problems have been Identified
at some sites.
A list of 40 wetland discharges was obtained from the Mississippi
Department of Natural Resources, Bureau of Pollution Control. The profile of
existing wetlands dischargers in this state was based on 13 positive
responses. Four additional responses indicated non-wetland discharges or
discontinued discharges.
Bayous are the predominant wetland type used for wetland discharges in
Mississippi. Pines, hardwoods and cattails characterize existing vegetation
in these wetlands. Approximately half of the respondents own the discharge
area; the other half use easements. The frequency of discharge is continuous
for 12 wetlands profiled; one wetland site received effluent on a daily
basis. Only one respondent indicated changes in the receiving waters since
discharge was initiated. The apparent change was a rise in the water table,
but other factors such as an atypical year of total rainfall may also have
lead to this response.
The most common problem associated with the profiled discharges was odor.
This invariably precipitated citizen complaint and regulatory difficulties.
The predominant effluent discharged is domestic with a range of 0.05 mgd to
0.5 mgd. Most respondents had no opinion regarding the usefulness of
wetlands for wastewater treatment and disposal. Table 3.5 profiles existing
wetlands in Mississippi.
A field trip was conducted in June 1982 to examine wetland systems and
discharges in Mississippi. Since the overwhelming majority of wetland dis-
charges were identified in northwest Mississippi, four sites in this area of
the state were selected for site visits. The wetlands which predominate in
the western portion of the state are derived from old river scars and are
typically oxbow shaped, forested wetland systems. Wetlands in this area of
the state are subject to intensive pressures because the rising demand for
agricultural products has placed a premium on tillable and marginally till-
able land. Wetlands in this area are also subject to a high level of agricul-
tural nonpoint runoff, which may contain potentially harmful pollutants
(pesticides, herbicides and fungicides). The following narratives detail the
observations made during the four selected site visits.
Tchula, MS. The town of Tchula is located approximately 70 miles north
of Jackson in a flat delta region of the state. The total wastewater treat-
ment system for the town of Tchula is represented by two separate lagoons,
each with a flow of approximately 0.1 mgd. A small brake containing dead and
91
-------
3.5 Continued
dying willows and sweetgum received effluent from one of the lagoons. This
brake further drained toward Tchula Lake (an oxbow lake); however, the
precise water course could not be traced. The effluent from the second
lagoon was piped approximately 1/4 mile to the banks of Tchula Lake. The
discharge area was viewed from the opposite side of the lake and contained an
abundance of macrophytes with little apparent degradation.
Itta Bena, MS. Itta Bena is located approximately 35 miles northwest of
Tchula. The wastewater treatment plant consists of a series of three lagoons
with aeration and chlorination. The 0.3 mgd discharge flows approximately
1/4 mile in a ditch before entering Gayden Brake. This forested wetland
begins at the end of the ditch and rapidly widens to over 3/4 mile. The
total drainage area for Gayden Brake is not large but approximately 75
percent is agricultural. The brake extends approximately two to three miles
southwest of the discharge and forms one end of Blue Lake, a large oxbow
lake. Gayden Brake is heavily forested by tupelo gum and cypress and did not
appear to be adversely affected by the sewage discharge. Blue Lake appeared
to be eutrophic, but this condition may be more related to nutrients in
agricultural runoff than from the influence of the sewage.
Webb, MS. Webb is located 35 miles north of Itta Bena. The recently
installed package plant is situated adjacent to the highway and soybean
fields and serves both Webb and Sumner. The discharge flows about 200 yards
to the thin remnant of a brake. This now channelized brake eventually flows
into Stanton Brake which we were unable to visit.
Tutwiler, MS. This lagoon system is located approximately ten miles from
Webb on the outskirts of Tutwiler, and the 0.1 mgd discharge is into Hobson
Bayou. Although a few cypress trees lined the banks of the bayou, it has
been channelized and represents a sparsely forested creek. Channelization
was initiated several years ago to reduce flooding in the town. The stream
now represents a remnant wetland. The effluent from the lagoons did not
constitute a large percentage of the flow at the time of this field
i nvestigation.
92
-------
Table 3.5. The Profile of Wetlands Discharges Based on Questionnaire Response for Mississippi.
10
CO
Discharge Wetland
Number Tvoe
Time Since
Typical Easement or Discharge Discharge
Discharge
Wetlands Related
Effluent Type Are Wetlands Useful'
and Average for Wastewater Treatment
1
2
7
4
5
6
7
8
9
Bog Creek
Bayou
Bog
Bayou
Lake
Bayou
Bayou
Large ditch
Bayou
0
Pine, mixed
hardwood
Hardwoods,
cattail ,
algae
Hardwoods,
oak, tupelo
-
Burmuda
grass,
Johnson grass
-
Soybeans
-
Easement
Easement
Easement
Easement
-
Ownership
Ownership
Ownership
Ownership
20 years Continuous None
33 years Continuous None
10 years Continuous Rise in
water
table
10 years Continuous None
18 years - None
18 years Continuous None
21 years Continuous None
24 years - None
18 years Continuous None
r i uu i ein:>
None
None
Overflow of
solids from
plant
None
None
None
None
Regulatory
problems
caused by
overloaded
flow and sus-
pended solids
None
ug i i y r i uw gnu/ui uiapuaai
Domestic I believe effluent far exce
0.113 mgd quality of creek area runof
Domestic Yes
Domestic No
0. 5 mgd
Domestic and
1 industrial,
plastic industry
Cooling water -
No
Cooling water -
Industrial
and domestic
0.15 mgd
•
Domestic
0.05 mgd
10 Bayou
11
Bayou
Hardwoods - 20 years Continuous None
Easement 20 years Continuous None
Citizen com- Domestic
plaints about
odor problems
In summer
Citizen com- Domestic
plaints 0.6 mgd
about odor
problems in
summer
Yes
-------
Table 3.5. Continued.
Discharge
Number
12
13
Wetland
Type
Flowing creek
Bayou
Typical
Vegetation
Pine, hard-
wood cattails
Water grass,
willows
Easement or
Ownership
Ownership
Easement
Time Since
Discharge
Began
10 years
17 years
Discharge
Frequency
Daily
Continuous
Wetlands
Impacts
None
None
Discharge
Related
Problems
Erosion
around
lagoons
Fish indus-
try over
loaded
lagoon caus-
ing odor
problems
Effluent Type
and Average
Daily Flow
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
Domestic plus
an oi 1 mi 1 1
and wood factory
Domestic and
one fish
industry
Source: Survey of wetland dischargers conducted by Claude Terry & Associates, Inc., Spring 1982.
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.6 North Carolina
SWAMP ECOSYSTEMS ARE USED FOR WASTEWATER DISPOSAL IN NORTH CAROLINA
North Carolina has the most wetlands discharges of all
Region IV states. Information was received from a small
percentage of dischargers, so additional assistance was
requested from NCDEM. Regulatory problems and citizen
complaints have been experienced by some respondents.
The North Carolina Department of Natural Resources, Division of Environ-
mental Management (NCDEM), lists 267 discharges into waters classified as
"swamp waters". To obtain a shorter list, a selection process was developed
based on two specific criteria. First, only those wetland areas receiving
discharges greater than 0.1 mgd were selected. Second, only those areas
discharging effluent directly into wetland waters were selected. The final
list contained 61 discharges; of these, 36 responses were received resulting
in a total response rate of approximately 59 percent. Of the 36 total
responses, only 21 were positive; the other 15 negative responses indicated
non-wetland or discontinued discharges. Several industrial discharges
refused participation. Eight of the positive responses were provided by
NCDEM.
River swamps and swamp creeks appear to be the predominant type of wet-
land used for wastewater disposal in North Carolina. Typical vegetation in
these swamps include cypress, maple, sweetgum, oak, and various emergent
plants. The average length of discharge is approximately 16 years with a
range from four years to 26 years. Most discharges are continuous. Few dis-
chargers indicated any apparent changes in the wetland; two discharges indi-
cated dissolved oxygen problems. Regulatory problems were cited by several
dischargers, including the surveys completed by NCDEM. Surveys completed by
NCDEM also indicated several violations of effluent limitations. Most dis-
charges consist of domestic wastewater; however, industrial components were
included in several systems. Flow varied widely and conflicted with the
original screening criteria in several instances. Reported flows averaged
approximately 2.0 mgd with a range of 30.0 mgd to .02 mgd; most discharges
are less than 1 mgd. Specific information concerning the 21 profiled dis-
charges is included in Table 3.6.
To supplement the sketchy profile data, a field trip to North Carolina
was taken in early June 1982. Due to time constraints and logistics, only
two sites were visited in the south coastal plain of North Carolina.
Lake Waccamaw, N.C. The town of Lake Waccamaw, North Carolina, is served
by a secondary treatment facility supplemented by a holding pond and aerated
pond. This .15 mgd facility discharges to a well-defined channel which
drains immediately into a bottomland hardwood swamp. Duckweed was abundant
in the channel and swamp.
Whiteville, N.C.. The town of Whiteville, North Carolina, is served by a
2.5 mgd wastewater treatment facility which incorporates an oxidation ditch
with post aeration. Thf; facility has a current discharge of approximately
95
-------
3.6 Continued
1.5 mgd into a canal which drains directly into a bottomland hardwood swamp
within 200 yards (Whitemarsh Swamp). Eventual drainage is to Lake Waccamaw.
No apparent impacts or problems were identified at this site; however, very
little of the impacted wetland area was observed. No monitoring of the
wetland area takes place.
96
-------
Table 3.6. The Profile of Wetlands Discharges Based on Questionnaire Response for North Carolina.
Discharge Wetland
Number Type
1
2
3
4
5
6
7
8
9
River Swamp
River
Creek
Swamp
Classic
swamp
Swamp
creek
River
swamp
Hardwood
swamp
Swamp
creek
Typical Easement or
Vegetation Ownership
Hardwoods, Easement
cypress
Easement
Hardwoods, Easement
shrubs
Pines Easement
Cattails Easement
Hardwoods Ownership
Cypress, Easement
pine, oak,
gum
Cypress Easement
Maple, gum, Easement
cypress, cat-
Time Since Discharge Effluent Type Are Wetlands Useful
Discharge Discharge Wetlands Related and Average for Wastewater Treatment
Began Frequency Impacts Problems Daily Flow and/or Disposal
14 years Continuous None Chlorination Domestic
system has 0.085 mgd
failed, caus-
causing water
quality problems
26 years Daily None None Domestic
0.350 mgd
20 years Continuous None Regulatory Domestic
problems 0.165 mgd
Daily None None Domestic
0.067 mgd
7 years Daily Increased None Domestic
vegetation,
decreased
dissolved
oxygen, algae
blooms.
18 years Continuous None Regulatory Domestic
difficulties 0.350 mgd
13 years Continuous Increased Citizen com- Industrial
color plaints 30.0 mgd
during low centered
flows. around color
Dissolved issue
oxygen
problems
(9.5-1.0 mg/1)
9 years Continuous None None Domestic
1.3 mgd
14 years Continuous Increase None Domestic
in vegeta- 0.846 mgd
Wetlands should only be
used for disposal of highly
treated waste. Tertiary
treatment should be require
_
_
In our case, wetland dis-
posal has been satisf actor;
Yes
Yes
May provide reduction of
nutrients where needed.
Wetlands are useful but
it depends on topography
and wetlands1 ability to
contain effluent.
Yes
tails, reeds,
Spanish moss
tion
-------
Table 3.6. Continued.
Time Since
10
oo
Discharge Wetland Typical Easement or Discharge
Number Type Vegetation Ownership Began
10
11
12
13
14
15
16
17
18
19
20
21
Source:
River swamp - Easement
Swamp creek Hardwoods
Swamp creek - Easement
(intermittent)
Swamp creek Hardwoods, Ownership
cattails,
grasses
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Survey Of wetland disrharnorc rnnHurtoH
5 years
21 years
-
45 years
15 years
7 years
20 years
4 years
4 years
18 years
24 years
14 years
kw PI 91.,4/t T«~~
Discharge
Frequency
Daily
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
uiscnarge
Wetlands Related
Impacts Problems
None None
Possible Regulatory
rise in problems
water level
None None
Possible Beavers
rise in
water level ,
could be
caused by
beavers
Regulatory
problems/
ef f 1 uent
limits
Regulatory
problems/
effluent
limits
Effluent
limits
None
None
Effluent
limits
None
Effluent
limits
trnuent lype Are Wetlands Useful
and Average for Wastewater Treatment
Daily Flow and/or Disposal
Domestic
1.0 mgd
Domestic No real advantage to using
.321 mgd wetlands
Domestic No opinion
.4 mgd
Domestic Possibly
.35 mgd
Domestic Yes
.37 mgd
Domestic
.132 mgd
Domestic
.317 mgd
Domestic
Industrial
2.4 mgd
Domestic
.02 mgd
Domestic
.153 mgd
Domestic/
Industrial
1.042 mgd
Domestic/
Industrial/
Cooling water
.021 mgd
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.7 South Carolina
SOUTH CAROLINA WETLAND DISCHARGE AREAS ARE PREDOMINANTLY
SWAMP CREEK ECOSYSTEMS
South Carolina provided the highest percentage of returned
Information forms. As a result, 1t Is the most complete
profile. Several discharges have been occurring for many
years, with an average period of 19 years.
A list of 31 individual wetlands dischargers representing 34 discharges
was obtained from the South Carolina Department of Health and Environmental
Control. The profile of existing wetlands in South Carolina was based on 21
responses representing 23 discharges; only one negative response was received
indicating a system not yet in operation.
Swamp creeks are the dominant type of wetland in South Carolina used for
wastewater disposal. Typical vegetation in these wetlands include cattail,
oak, black gum, sweetgum, cypress, tupelo and duckweed. Approximately half
the respondents own the discharge area. The frequency of discharge for 22
profiled areas is continuous, and the period of discharge ranges from one
year to 100 years. The mean period of discharge is 19 years. According to
17 respondents, no changes in the receiving waters have occurred since
discharging began. The most common problem relating to the discharge is
regulatory difficulties, but this problem was infrequent, and the majority of
respondents indicated no discharge-associated problems. The typical effluent
discharged into wetlands is domestic. The range of effluent flow for 11
areas profiled is 0.015 mgd to 5.0 mgd. In general, respondents feel that
wetlands are useful for wastewater disposal. However, one respondent
stressed that swamps with little or no flow are poor choices for wastewater
disposal. Table 3.7 profiles existing wetlands discharges in South Carolina.
A field trip was taken in early June 1982, to provide first-hand
knowledge concerning wetland systems and discharges in South Carolina. This
series of site visits is summarized in the narratives below.
Berkeley County, SC. Five treatment plants with disposal to wetlands
were visited under the guidance of the Berkeley County sewer authority. Fair-
fax subdivision has a small 0.020 mgd package plant that discharges to a
bottomland hardwood swamp. Crowfield subdivision has a similar type dis-
charge from a 0.010 mgd package plant. The discharge flows through a channel
several hundred yards before actually discharging to the swamp and was the
subject of an inquiry by EPA due to potential problems resulting from the
extensive development near the area. The Beverly Hills subdivision flows
through a series of lagoons to another bottomland hardwood swamp, with a flow
of 0.040 mgd. This treatment system employs diquat to control weeds around
and in the lagoons, which raises a valid concern about potential impacts of
herbicides on wetlands.
The final two systems visited were the Conifer Hall and Sangaree
subdivisions. Conifer Hall is not considered a swamp discharge by the state
bat is similar to the previous discharges described. This again indicates
99
-------
3.7 Continued
the potential problem with the definition of wetlands discharges between and
within the states of Region IV. The Sangaree subdivision is a 0.40 mgd plant
with brush aerators that discharges to a canal that empties into a forest
swamp. The canal was extensively covered with floating, submergent and
emergent vegetation both upstream and downstream from the point of discharge.
Andrews, SC. The city of Andrews, South Carolina, represents one of the
few communities that has been involved in litigation over impacts to wet-
lands. For several years the municipal treatment plant, combined with two
major industrial dischargers, has been discharging to a marsh-swamp system of
cattails, hardwoods, and cypress. The wetland has been stressed as indicated
by the death of numerous hardwoods. Potential causes include increased flows
to the area with a change in the hydroperiod, toxic substances in the indus-
trial effluent, and increased runoff and other impacts from road construction
through the wetland. The 201 Plan Addendum still proposes use of the wetland
areas for disposal of effluent by upgrading the lagoons which currently com-
pose the system, purchasing the swamp, and continuing the discharge, which
ranges between 2-2.5 mgd. About 1000 acres of wetland area would be
purchased.
Loris, SC. The wastewater system at Loris, South Carolina, provides
minimal treatment prior to discharge to the wetland, which is a forest swamp.
The treatment system is composed of an oxidation pond containing large quan-
tities of suspended and floating matter. Flow from the Loris system is about
0.325 mgd. Due to dense understory, the wetlands system was not examined in
detail.
Lake City, SC. The treatment facility at Lake City was the most sophis-
ticated of any facility visited in South Carolina. The plant incorporates a
series of screens, an aerator, clarifier/sedinientation basin, rotating biolog-
ical contactors, chlorine contact chamber, and oxygenation steps prior to wet-
lands discharge. Loris and Lake City represent the two extremes of pretreat-
ment observed during the site visits. Lake City does have an industrial
component in its wastewater that results in coloring the wastewater red. The
treatment facility does not totally remove the dyes and, therefore, they are
discharged to the wetland, which is a bottomland hardwood swamp. Impacts of
the dye on this wetland system are unknown.
Florence, SC. The city of Florence, South Carolina, has a sophisticated
secondary treatment facility with nitrification. It was the largest treat-
ment plant visited, with a flow of 9 mgd. The discharge enters a channel
that cuts through a bottomland hardwood swamp. At one time the effluent
moved more as sheet flow across the wetland; however, the discharge cut a
channel through which the effluent now flows, and the treatment plant opera-
tor indicated that impacts to the remainder of the wetland are now minimal.
As a result, the discharge is not a pure wetlands discharge in that it rarely
overflows the banks of the channel to impact the wetland. However, the
channel transecting the wetland may have some influence on the hydrologic
pattern of the wetland.
100
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Table 3.7. The Profile of Wetlands Discharges Based on Questionnaire Response for South Carolina.
Number
3e Wetland
Type
River swamp
Pocataligo
Ri ver
Swamp creek
Swamp
Swamp
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Typical
Vegetation
Cattails
-
Cattail,
tupel o
cypress,
hardwood
Hardwood
Cypress, duck
weed, dead
hardwoods
Hardwoods,
pines, reeds
Dense aquatic
vegetation
and hardwoods
typical swamp
Pine, hard-
wnnrlc
W WUU J
Sweetgum,
CVDTGSS
T*J r * *»«*«*
lime bince
Easement or Discharge
Ownership Began
45 years
4.5 years
Easement 32 years
Ownership 8 years
17 years
Ownership 20 years
Ownership 10 years
9
Ownership 12 years
Discharge
Frequency
Continuous
Daily
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Wetlands
Impacts
Some trees
have died
because
logging
roads were
built
Rise in
water
table .
None
None
-
Occasional
algae
bl ooms
None
None
Discharge Effluent Type
Related and Average
Problems Daily Flow
Complaint Domestic and
by present industrial
land owner 1.2 mgd
over using
his land
without
compensation
None Domestic and
industrial
5.0 mgd
None Domestic
_
None Domestic
0.015 mgd
NPDEDS permit Domestic
to replace 0.25 mgd
present per-
mit has very
strict limi-
tations
None Domestic plus
one industry
Occasional Industrial
permit 0.5 mgd
Citizen com- Domestic (90%)
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
Yes. Wetlands for ter-
tiary treatment is a good
alternative.
No improvement occurs as
a result of wetland itself.
Yes
Wetlands especially swamps
with low flow are poor
choices, for waste disposal.
Yes
In cases where nutrient
levels will be consistantly
low and toxic substances are
closely controlled.
Yes
plaints re- industrial (10%)
Easement 13 years
Continuous
None
garding 0.15-0.5 mgd
nearby septic
tank malfunc-
tion
None Domestic and
Industrial
3.0 mgd
Yes
-------
Table 3.7. Continued.
Discharge Wetland
Number Type
10
11
12
13
14
15
16
17
18
Swamp creek
Swamp
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
Swamp creek
River swamp
Typical
Vegetation
Black gum,
cypress,
hardwood
Hardwood
Hardwood,
cattails
Surface
algae, cat-
tails, bot-
tomland
hardwoods
-
-
Hardwoods
Hardwoods
Hardwoods
Time Since
Easement or Discharge
Ownership Began
Ownership 15 years
Ownership 27 years
Easement 19 years
Easement 10 years
Yes
Yes 2 years
Ownership 30 years
6 years
14 years
Discharge
Frequency
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
(seasonal )
Continuous
Continuous
Continuous
Wetlands
Impacts
None
None
None
Increased
vegetation
-
None
Vegeta-
tion loss
None
None
Discharge
Related
Problems
None
Discharge
does not
meet NPDES
requirements
Odor problems
caused citi-
zen complaints
Water quality
parameters
do not meet
NPDES
requi rements
None
None
Regulatory
problems w/
DHEC
None
Problems
concerning
the require-
ments of PL-
92-500 as
amended and
priority for
upgraded
funding
Effluent Type
and Average
Daily Flow
Domestic
-
Domestic
0.3 mgd
Domestic
_
Domestic
0.037 mgd
Domestic
Domestic
Domestic
1.4 mgd
Domestic
0.025 mgd
Domestic
0.20 mgd
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
Yes, but obtain complete
information regarding
effluent quality and monitc
wetland water quality.
_
Yes
Yes
-
Only if treatment facility
discharges high quality
effluent.
Yes
Treatment should be accom-
plished prior to discharge.
Yes
-------
Table 3.7. Continued.
Easement or Discharge Discharge
Vegetation Ownership Began Frequency
Discharge
Wetlands Related
Impacts Problems
Effluent Type Are Wetlands Useful
and Average for Wastewater Treatment
Daily Flow and/or Disposal
o
co
19
20
21
22
Swamp creek Hardwoods Easement 9 years Continuous None
Swamp creek Hardwoods, Easement 1 year Continuous None
pines
Swamp creek
Easement 2 years Continuous None
River swamp Hardwoods Easement 100 years Continuous None
Infrequent Domestic
permit vio- .07 mgd
lations, odor
problems
None
None
None
Source: Survey of wetland dischargers conducted by Claude Terry & Associates, Inc., Spring 1982.
Domestic
Domestic
Domestic
(90%)
Industrial
(10%)
No opinion
Yes, as long as high quality
effluent is maintained
Yes
-------
3.0 PROFILE OF EXISTING WETLAND DISCHARGES
3.8 Tennessee
FREQUENTLY USED WETLAND DISCHARGE AREAS IN TENNESSEE INCLUDE
RIVER SWAMPS AND SWAMP CREEKS
The profile of existing wetlands discharges in Tennessee
was based on six responses from a list of ten dischargers.
The profile reflects discharges to large, typically wet
areas such as backwaters, old channels and swamps. Most
wetland discharges in Tennessee have been long-term and
continuous.
A list of ten wetland dischargers representing 12 individual discharges
was provided by the Southwest Regional Office of the Tennessee Division of
Water Quality Control. State officials earlier indicated that all wetlands
and wetlands discharges are located in west Tennessee. Of the ten dis-
chargers, six responded, representing eight individual discharges.
River swamps and swamp creeks represent the wetland types most frequently
used as discharge areas in Tennessee. Typical vegetation in these ecosystems
includes hardwoods, cypress and cattail. Half of the respondents obtained an
easement to discharge; the remaining respondents own the area. The average
period of discharge for all profiled areas is approximately 18 years. The
frequency of discharge is continuous for seven areas and daily for one area.
Significant increases in algae in receiving waters were noted by four respon-
dents, and a variety of problems relating to discharge operation was indi-
cated. Several problems were engineering-oriented and resulted in temporary
degradation of the discharge area. Domestic effluent is the type discharged
at six areas. One area discharges industrial effluent, and the other area
discharges cooling water. The average daily effluent flow is 0.70 mgd, the
range being from 0.03 mgd to 2.74 mgd. The majority of respondents concluded
that wetlands are useful for wastewater treatment and disposal. Table 3.8
profiles existing wetlands discharges in Tennessee.
A field trip was conducted through west Tennessee in early June 1982 to
survey three wetland discharges. The wetlands in Tennessee are predominated
by riverine swamps in the form of bottomland hardwood communities. The
following narratives describe the visited sites.
Brunswick, TN. A small package plant serves the town of Brunswick,
Tennessee, located approximately 15 miles northeast of Memphis. This package
plant is operating above design capacity and discharges approximately 0.05
mgd to an old river channel draining into the Loosahatchie River. A sizeable
number of dead trees (oaks, birch) were located in the immediate discharge
area; however, it could not be determined if this problem was related to
water quality or quantity. Further downstream from the discharge, the trees
appeared to be healthy, and thick underbrush was apparent. The actual dis-
charge point to the Loosahatchie River could not be located due to inacces-
sibility. Algae blooms and beaver dams are two operational/water quality
problems noted by the discharger.
104
-------
3.8 Continued
Moscow. TN. A simple lagoon system serves the town of Moscow, Tennessee,
and currently discharges directly into a riverine swamp forest (Wolf River).
At the time of the site visit the river channel was swollen by recent rains
and measured approximately 75-100 feet across. Numerous cypress and gum
trees of all sizes dominated the shallow floodplain, and cypress seedlings
were noted along the edge of the river. The actual outfall could not be
located since it was underwater at this flood stage. The zone of discharge
was distinguishable by color and emergent macrophytes, which were especially
thick at the discharge zone. A small stand of dead gum and cypress trees was
located in the proximity of the outfall area; however, the cause of this tree
kill is unknown.
Bolivar, TN. The town of Bolivar, Tennessee, is served by a standard
secondary treatment plant using a trickling filter and clarifier. This plant
discharges approximately 0.35 mgd into nearby Spring Creek and has been
operating continuously for 27 years. Spring Creek eventually flows into
"Hatchie Bottom" (Hatchie River), which is a large flat area braided with
numerous streams. The Hatchie River is a heavily forested river swamp
designated as a Scenic River.
The discharge area was heavily forested with mixed bottomland hardwoods
and cypress. The meandering stream channel readily changes with the flow
because the land is extremely flat. The volume of the discharge was minimal
compared to the total creek flow and wildlife was plentiful in the area.
Beavers frequently dam portions of the stream, causing shifts in the stream
channel and occasional tree kills.
105
-------
Table 3.8. The Profile of Wetlands Discharges Based on Questionnaire Response for Tennessee.
Discharge Wetland Typical
Number Type Vegetation
1 River swamp Small hard-
woods
2 River swamp Hardwoods,
cattails
Easement or
Ownership
Easement
Easement
Time Since
Discharge
Began
8 years
6 years
Discharge
Frequency
Continuous
Continuous
Wetlands
Impacts
Algae
growth
along
swamp
edge
Great in-
crease in
algae con
Discharge
Related
Problems
Excess
solids from
food pro-
cessing
plant has
caused odor
problems
No flow in
swamp
-
Effluent Type
and Average
Daily Flow
Industrial
(food pro-
cessing)
2.74 mgd
Domestic
0.03 mgd
centrations.
Are Wetlands Useful
for Wastewater Treatment
and/or Disposal
No
Where wetlands have
flowing water, it is
very efficient means
of disposal.
free
a
of
Beavers dammed
H- '
0
01 3 Swamp creek
4 Swamp creek
5 Swamp creek Cattails
6 Swamp creek Hardwoods,
cypress
7 Swamp creek Cattails,
hedge-hyssop,
sedge grasses
8 River swamp Cypress,
bottomland
hardwoods
Ownership
Ownership
Ownership
Easement
Easement
Ownership
22 years
18 years
12 years
27 years
29 years
20 years
Continuous
Continuous
Continuous
Daily
Continuous
Continuous
lower end
river.
Algae in
discharge
Algae in
discharge
None
None
None
None
of
Odor prob-
lems
None
Problems
with BOD and
suspended
solids
None
None
None
Domestic
0.07 mgd
Domestic
0.6 mgd
Cooling water
0.108 mgd
Domestic
0.35 mgd
Domestic
1.0 mgd
Domestic
Yes
Yes
Yes
Yes, for secondary
treated waste.
Yes
Yes. Funding assistance
is necessary for wetlands
manaoement
Source: Survey of wetland dischargers conducted by Claude Terry & Associates, Inc., Spring 1982.
-------
SECTION 4
NATURAL WETLANDS CHARACTERISTICS
-------
-------
4.0 NATURAL WETLAND CHARACTERISTICS
SPECIFIC WETLAND CHARACTERISTICS BASED ON THE INTERACTION
OF SOILS, HYDROLOGY, VEGETATION AND GEOMORPHOLOGY
The major components of wetland ecosystems interact to
form and contribute to the basic fabric and Integral
function of wetlands. The hydrology, vegetation* water
quality, wildlife and geomorphology of wetlands are the
key elements identified and discussed in this section.
These elements are discussed from the standpoint of
preservation of their natural function and the potential
impacts from wastewater addition.
The physical form of wetlands imparted by the geomorphology of the region
provides a basis for defining and characterizing typical wetland types. The
geomorphology of wetlands in Region IV states is characterized by a variety
of geologic formations and physiographic provinces including floodplains,
piedmonts and karstic areas, he majority of soils found in southeastern
wetlands are highly organic although clays and loams are typical of alluvial
plain wetlands.
The vegetation of wetlands form the basis for energy and material cycling
and are among the most productive ecosystems in the world. However, not all
wetlands within Region IV are highly productive. The vegetation is adapted
for life with some level of flooding. The predominant vegetation types form
the basis for the classification of wetlands. An understanding of the
ecology and succession of wetland vegetation is necessary to maintain the
natural structure and function of wetland ecosystems. This is especially
true in preserving rare and valuable wetland ecosystems.
The hydrologic regime is the key regulator of wetland ecosystems. It
influences the type of vegetation able to grow in wetlands and regulates the
movement of nutrients into and out of wetlands. The hydrologic character-
istics of wetlands define the filtration, buffering, storage and groundwater
recharge capacity of wetlands types. Many factors contribute to the hydro-
logic characteristics of wetlands including physical characteristics, soils,
and vegetation. Thus many wetland types have their own unique sets of
hydrologic characteristics.
Water quality in wetlands is a complex set of often locally important
chemical and biological parameters. The levels of pH and DO are typically
low in wetlands. Heavy metals are commonly bound to sediments when intro-
duced into wetlands, but many questions need to be resolved in this area.
Nutrient levels and cycling characteristics vary among wetlands. Many
wetlands act as a sink for nitrogen and phosphorus, while tidal freshwater
and alluvial wetlands may act as a source or sink. Carbon and sulfur cycles
are also important from the perspective of wastewater recycling. Most
endemic microorganisms in wetlands serve to decompose organic matter and
provide an important service of recycling nutrients. Endemic populations of
encephalitis-causing microorganisms sometimes form significant reservoirs in
mosquito and bird populations in wetlands.
107
-------
4.0 Continued
The value of wetlands as wildlife habitat and food source is well docu-
mented. Wetlands have received much attention as a reservoir of threatened
and endangered species. Perturbation or destruction of wetlands can result
in loss of wildlife or rare and endangered species.
Issues of Interest
• What are the major natural characteristics of wetlands within Region IV?
• How do these characteristics interrelate?
• Why are natural characteristics important to wetlands structure and
function?
• Which natural characteristics are likely to be affected by wastewater
application?
• What are the major physical characteristics of wetlands within Region IV?
• How is vegetation important in wetland ecosystems?
• What role does hydrology have in maintaining and regulating wetland
ecosystems?
• What water quality parameters are important in natural wetlands and are
these parameters affected by wastewater addition?
• Why are wetlands valuable to wildlife? Which threatened and endangered
species are dependent on wetlands?
108
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4.0 NATURAL WETLAND CHARACTERISTICS
4.1 Geomorphol ogy
PHYSICAL CHARACTERISTICS HELP DEFINE WETLANDS
The physical characteristics of wetlands systems are the
result of geology, soils, vegetation, and hyd rope Mod.
Common physical characteristics such as geology and topo-
graphy help distinguish different types of wetlands.
Wetlands systems have distinct physical characteristics that relate
directly to their occurrence and sustenance. The series of profiles illus-
trated in Figures 4.1-a through 4.1-f indicate the relationship of the sys-
tems to underlying substrate and/or topography. Dependent on the depth to
the water table, proximity to surface waters and surface water depth, wet-
lands systems of different types exhibit rather common physical characteris-
tics. The vegetation assemblage which develops depends on geology, soils,
hydrologic cycle, water chemistry, and moisture conditions. Each of these
elements will be discussed in detail in later sections. However, these
combine to form the typical physical characteristics that are associated with
different wetlands systems.
The geology and soils of wetlands play a significant role in the forma-
tion of wetlands and greatly influence their use for wastewater disposal.
Throughout the Southeast, wetlands are usually associated with river flood-
plains and lakes, karstic (limestone) areas, or perched water tables. Geo-
logic considerations are important when determining the potential for deep
aquifer wastewater contamination through direct recharge from wetlands. This
potential for groundwater contamination may be greatest with karstic forma-
tions; however, wetland systems associated with karstic dissolutions, such as
some cypress domes, are not well understood. The cypress dome profile pre-
sented in Figure 4.1-a provides an orientation to the fundamental physical
characteristics of a cypress dome receiving wastewater. The transition of
submergent to emergent vegetation in a marsh wetland community is presented
in profile in Figure 4.1-b. A similar profile of a transition between a
riparian to a bottomland hardwood community is presented in Table 4.1-c.
Wetland types can be highly interspersed due to changes in basin physiography
as is illustrated in Figure 4.1-d. Fine differences in the vegetational
assemblege within a wetland type may reflect subtle changes in the physio-
graphy. Various components of a bottomland hardwood ecosystem are profiled
in Figure 4.1-e.
The predominantly organic soils associated with southeastern wetlands
also have an important function in the formation and maintenance of wetlands.
Fine-grained, highly decomposed peat soils are associated with many types of
wetlands from North Carolina (pocosins, Carolina Bays) to Florida (cypress
and gum domes). A profile of the soil layers beneath a North Carolina poco-
sin is presented in Figure 4.1-f. The presence and extent of various soil
layers varies considerably among wetland types. Decomposition of these peat
soils slows percolation. Kaolinate clay interfaces existing below peat soils
in Florida cypress domes further impede subsurface water movement. This
subsurface phenomena in conjunction with wetland hydrology and vegetation are
important considerations when determining wastewater disposal potential.
Soils such as marsh soils also affect nutrient cycling in wetlands and can
further impact wastewater disposal alternatives.
109
-------
Cypress Dome
Pineland
Surface
Groundwater
Figure 4.1-a. Physical profile of cypress dome receiving sewage effluent.
Source: Odum, et al.
-------
Figure 4.1-b. Profile of submergent and emergent wetland marsh community.
Source: Darnell et al. 1976.
-------
ro
Taxodium distichum, Bold Cypress
Cephalanthus occidenfo/is. Common buttonbush
P/onero oquofico. Water elm
Salix nigra. Black willow
Foresfiero ocuminofa. Swamp privet
8efu/o nigra, River birch
Riparian Swamp
Diospyros virginiono. Persimmon
Quercus lyrata, Overcup ook
Crofoegus viridis, Green hawthorn
Ce/t/'s laevigata, Sugar berry
Popo/us deltoides. Eastern Cottonwood
Coryo oquofico, Bitter pecan
G/editsio frioconfhos. Honey loCUSt
First Terrace,
Bottomland Hardwood
Liquidambar styraciflua, Sweet gum
Ouercus nutlallii, Nuttoll's oak
Ouercus phe/fos. Willow oak
Ouercus nigra. Water oak
Ilex decidua, Possum haw
Second Terrace
Bottomland Hardwood
Pinus spp.
Pine
Upland
Figure 4.1-c. Transition from riparian wetlands to bottomland hardwoods.
Source: COE. 1978.
-------
WATER
LEVEL
Taxodium distichum, Bald cypress
Cypress Swamp
Juncus effusus. Soft Sedge
Cy penis spp., Cyp«ruS
E/eochoris spp., Spikerush
Sagittorio spp.. Arrowhead
Rhynchospora spp., Beaked Sedge
Marsh
Carcx spp.. Sedge
Polygonum spp.,
Smartweed
Cepho/onthus occidcntalis,
Buttonbush
Boccharfs ha/f'mjfo/ia.
Sea-myrtle
A/nus serrufota. Common
alder
Crofoegos vlridis. Green
hawthorn
Shrub Swamp
Ooercus nigra. Water oak
Ouercus pheffos. Willow oak
L/quidbmbar styracifluo, Sweet Gum
Ce/fis /oev/gafo, Sugarberry
Nyssa sylvatico, Black gum
Acer rvbrum. Red maple
Mixed Hardwood Swamp
Figure 4.1-d. Profile of transition between several common wetland types.
Source: COE. 1978.
-------
Stream
Channel
Better drained than backswamp
Low ridge
Backswamp
Water hickory
Overcup oak
Hackberry
Laurel oak
Overcup oak
Red maple
Green ash
Levee
Silver maple
River birch
Willow
Cottonwood
Oxbow
Water elm
Tupelo
Cypress
High ridge
White oak
Blackgum
Hickory
Blackgum
Water oak
Swamp chestnut oak
Cherrybark oak
Upland-
forest
Low ridge
Green ash
Sweetgum
Willow oak
Flats
Sweet gum
Willow oak
Laurel oak
High ridge
Live oak
Loblolly pine
FIRST BOTTOM
SECOND BOTTOM
SOUTHEASTERN BOTTOMLAND HARDWOOD;
Figure 4.1-e. Profiled, various components of the bottomland hardwoods ecosystem.
Source: Brinson, et al. 1981.
-------
Canal
Well 3
Well 9
Well
_, 16-,
UJ
_J
< '2-
LU
^ 10-
LU 8 "
i
6-
2-
0-
2000
i
100
500
3000 FEET
!000 METERS
•16
• 14
-12
-10
- 8
-6
- 4
-2
-0
-4
~ 3
>
o
CO
cc
LU
o
S tratigraphic section
Figure 4.1-f. Stratigraphic profile of soil beneath a pocosin wetland.
Source: Daniel. 1981.
-------
4.0 NATURAL WETLAND CHARACTERISTICS
4.1 Geomorphology
4.1.1 Geology
GEOLOGY HAS MAJOR INFLUENCE ON FORMATION OF WETLANDS
The geological characteristics of an area have a direct
impact on the formation and maintenance of wetlands. Of
particular interest to this study are formations which
lead to direct recharge of aquifers.
The Region IV states are characterized by a variety of geologic forma-
tions and physiographic provinces. The Mississippi River system borders the
region on the west and has a large influence on wetlands due to its extensive
floodplain. The north central area is transected by the Blue Ridge mountains
and is adjacent to the Ridge and Valley Province characterized by series of
faults and folds which form the ridges and valleys. These mountainous areas
transform into the Piedmont, which is rolling terrain dominated by clay
soils. Moving to the south and southeast, a fault line separates the Piedmont
from the Coastal Plain. This line occurs approximately across the middle of
the states of Alabama, Georgia, South and North Carolina. The Coastal Plain
is characterized by geologically recent sedimentary deposits formed by
changes in sea level.
Numerous geological surveys of these areas have been undertaken to study
the origin of substrate and outcrops, formation of land forms, and source of
soils. As a result, these will not be discussed in this section. Rather,
this section concentrates on correlating the formation and location of
wetlands areas with geologic processes.
Most wetlands are found in low lying areas where the water table is at or
near the surface. Many wetlands within Region IV are associated with river-
ine floodplains and areas contiguous to lakes. Many others are formed in
interior regions, unassociated with major surface water bodies. These wet-
lands are found in association with karstic (limestone) areas and perched
water tables (formed by near -surface impermeable substrate).
Karstic deposits are located primarily near the outer (seaward) portions
of the Coastal Plain. However, they are also found in other areas in Region
IV, as evidenced by the underground caverns located in portions of Tennessee
and Kentucky.
The geologic origin of some wetland systems is poorly understood. Caro-
lina bays, found in North and South Carolina, are unique systems whose
origins are not totally understood. Cypress dome systems appear to be the
result of karstic dissolution, but their origin is also less understood than
wetlands associated with contiguous surface waters.
Beyond understanding the origin of wetlands and why they are located in
certain areas, geology is important to this analysis of wetlands for its role
in the formation of recharge mechanisms. Wetlands have a direct interface
with shallow groundwater. For most wetlands systems, this interface is
116
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4.1.1 Continued
confined to the near surface or water table aquifer. Wetlands are extremely
important components of the hydrologic cycle and hydrologic regime of many
areas (See Section 4.3). But of major concern is an analysis of geologic
formations that connect wetlands to deeper aquifers that are a more direct
source of consumptive water supply.
The primary geologic formation associated with wetlands which leads to
direct deep aquifer recharge are karstic deposits, although others may exist.
Limestone deposits are particularly susceptible to dissolution, which opens
cavities across aquicludes and allows direct recharge. Figure 4.1.1 shows a
cross-section which typifies this situation. This type of formation is
predominantly found in Florida and near coastal areas of other Region IV
states. Other geologic process, while important to the formation and
maintenance of wetlands, are not likely to result in major impacts from
wastewater discharges. The specific importance of geologic factors in waste-
water recycling hinges upon the water balance and the presence or absence of
permeable or semi-permeable layers.
117
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00
Figure 4.1.1. Representative cross-section of karstic geology.
Source: Claude Terry & Associates, Inc. 1980.
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4.0 NATURAL WETLAND CHARACTERISTICS
4.1 Geomorphology
4.1.2 Soils
ORGANIC SOIL IS THE PREDOMINANT SOIL TYPE IN SOUTHEASTERN WETLANDS
Organic soils dominate the surface complex of most
southeastern wetlands. In alluvial plain wetlands, clays
and loams occur. In marsh soils, a thin aerobic surface
layer serves as a release mechanism for nitrogen and
Increases the soils' ability to serve as a storage
reservoir for phosphorus.
The majority of soils supporting southeastern wetlands are highly organ-
ic. These soils are commonly called bogs, moors, peats or mucks and are
grouped in the histosol order. Soil orders consist of broad groupings of
soils organized principally to show which soil-formation factor has had the
greatest influence in determining the properties of a soil. Histosols
develop in areas of impeded drainage where water stands on the soil surface
for long periods of time. The degree of decomposition is closely related to
fiber content and bulk density. Most histosols have bulk densities of less
than 1 g/cc which tends to increase with decomposition. Physical difference
between histosols relates to parent material, topography, time of development
and hydrologic fluctuations.
Histosol soils vary in other ways including, but not limited to percent
organic matter, water-holding capacity, pH and cation exchange capacity
(CEC). The CEC is a soil property which can remove significant amounts of
positively charged ions such as NH4+, K+ and others from waters in contact
with the soil. Organic soils generally have higher CECs than mineral soils
(Alexander 1977). The CEC is pH dependent. Further, the CEC increases as
decomposition increases. Anions (negatively charged ions) may also be sorbed
onto charged surfaces of peats (Kadlec and Tilton 1979). Nitrate is little
influenced by this process, but some phosphate removal may be attributed to
anion exchange. All these factors affect the nutrient absorptive capacity of
wetland soils. The nutrient removal capacity is in turn affected.
In North Carolina, peat supports three distinct wetlands: 1) pocosins;
2)river floodplains; 3) Carolina Bays (Ingram and Otte 1981). Peat deposits
are characterized as finegrained, highly decomposed hemic to sapric soils.
In general, two peats exist. The first is characterized as a mixture of
sedge and sphagnum peat associated with poor tree growth. The second type is
predominately sphagnum peat that is dome shaped and isolated from groundwater
sources (Very and Boelter 1978, Ingram and Otte 1981). As decomposition in
peat becomes complete, pore space size decreases and water drains less
easily. As a result, hydraulic conductivity is inversely related to the
degree of decomposition.
Peat soils are also characteristic of Florida's cypress and gum domes and
mixed hardwood domes. Spangler et al. (1975) analyzed soil profiles for
several cypress domes typical of north central Florida. The upper horizon
consists of a sapric peat followed by a zone of saturated coarse sand. A
confining layer of kaolinate clay separates the dome from direct connection
119
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4.1.2 Continued
with underlying aquifers and allows virtually no vertical movement of water.
Effluent disposal under these circumstances would be confined to the water
table aquifer. Not all domes conform to this geologic arrangement and have
different implications for wastewater management.
The diversity associated with alluvial floodplain soils is closely
related to inundation, vegetation and the source of water input. Water is
the primary factor that influences the type and properties of existing soils.
Where saturated soil conditions exist throughout the year, clays (alfisols
and inceptisol soil orders) usually dominate, and the soils exist in an
anaerobic condition. Where soil saturation occurs for shorter periods
(ultisols), clays and loams dominate, and an environment exists that is
favorable for vegetative root respiration (Clark and Benforado 1980, Soil
Survey Staff 1975).
The extent of soil saturation plays an important role in the development
of wetland soil characteristics. In the Southeast these soils exist in an
anaerobic condition, typify the alfisol soil order and maintain low redox
potentials. The anaerobic condition results in slow rates of decomposition
and mineralization. A thin aerobic oxidized surface layer (microzone) is
intermittently present in wetland soil profiles; the layer serves as a
regulatory mechanism for nitrogen release and increases the soil's ability to
serve as a storage reservoir for phosphorus (Klopatek 1978).
120
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
VEGETATION IS MAJOR CHARACTERISTIC OF WETLANDS
A variety of vegetation types comprise wetlands.
Different ecological processes, such as succession and
productivity, determine wetland characteristics and func-
tions. Various physical and biochemical components deter-
mine vegetative communities.
The vegetational characteristics of natural wetlands are among the best
studied attributes of natural wetlands. The vegetative component of wetlands
ecosystems have an important role in regulating hydraulic regimes, influ-
encing nutrient cycling and providing wildlife habitats. Vegetation types
are also important to soil processes and peat formation.
The types of vegetation which inhabit a particular wetland system are
dependent on several factors. Among the most important are hydroperiod,
soils and water chemistry. On a regional scale, climatic and
temperature/precipitation conditions also have a significant influence on
wetland communities, as certain species are limited to near coastal
sub-tropical environments. The type of predominant vegetation helps
differentiate wetlands.
Interactions between wetland components require that vegetation ecology
be understood. Knowledge of the successional pattern or stage of a system
assists in assessing the function of a wetland, its role with interacting
ecosystems, and its stability.
Wetlands are extremely productive natural ecosystems. They provide
habitat for a wide range of organisms during certain stages of their life
cycle. Wetlands provide an export of detritus and nutrients at certain times
of the year (in flowing wetland systems) which are critical to downstream
ecosystems and the organisms which inhabit them. Productivity is largely
dependent on interaction of the type of vegetation comprising a wetland,
nutrient availability and hydrologic stress.
In evaluating wetlands throughout Region IV, it is apparent that some
systems are particularly unique or limited in extent. These are identified
in Section 4.2.5 and will be given special attention.
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
4.2.1 Plant Ecology
PLANT ECOLOGY DESCRIBES INTERACTION OF WETLAND
STRUCTURE AND FUNCTION
A thorough understanding of the ecology of wetlands
vegetation Is Important to understanding how a wetland
functions. The impacts of hydrology, sedimentation, and
fire are important to the maintenance and succession of
wetlands vegetation.
The interplay of physical, chemical, and biological factors shape the com-
position and ecology of vegetational communities. Because each part of an
ecosystem is linked to another, the ecology of wetland vegetation is
intricately linked by the flow of materials and energy to other wetland com-
ponents such as wildlife, nutrient cycles, and hydrologic patterns.
Regional variations in precipitation, sunlight, and temperature are
important physical factors which determine the ecology of wetlands vegetation
in the Southeast. In general, the climate of Region IV is characterized by
distinct seasonal rhythms in temperature, mild winters and the absence of a
dry season. Annual rainfall varies from 40 to 65 inches and is generally dis-
tributed throughout the year.. In some cases, a large portion of the total
accumulates during the summer months. Even the northern areas of Region IV
(Kentucky, Tennessee) may experience over 250 frost-free days (Barry 1980).
The seasonal variations in these climatic variables determine the timing,
rates and extent of material flows in wetland plant environments. For
example, the pattern of nutrient uptake throughout the year in North Carolina
is quite different from that in Florida (Whigham and Bayley 1978).
Similarly, important primary trophic level processes such as growth season,
leaf fall, and productivity are seasonally related to local temperature and
moisture regimes. In turn, other trophic levels (second, third, detrital,
etc.) are affected. The life cycles of insects, soil organisms, reptiles and
birds are all adapted to primary trophic level processes. Therefore, the
ecology of wetland vegetation is important to the development and maintenance
of wetland plant and animal life.
The ecology of wetland plants includes the adaptation of plants for
survival and reproduction in wetlands. Adaptations to flood tolerance fall
into two categories, physical and metabolic (Teskey and Hinkley 1977). Both
types of adaptations have the similar purpose of decreasing the effects on
the plant of an anaerobic (low-oxygen) environment in the root zone produced
by high water levels. Physical mechanisms involve processes which increase
the oxygen content in the roots. This is accomplished either by transport of
oxygen from the upper part of the plant (stem lenticals, leaf stomatas) or
from parts of the system where oxygen is more available in secondary and ad-
ventitious (above-ground) or possibly knee (cypress knee) roots (Brown 1981).
Metabolic modification to anaerobic respiration enables plants to utilize
less toxic end products or discharge toxic volatiles through leaf stomata.
122
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4.2.1 Continued
Wetland grasses, sedges and rushes which dominate marshes have the option
of asexual reproduction which amplifies reproductive processes and species
maintenance. Trees and most herbaceous species are dependent upon successful
pollination, seed production, seed germination and seedling survival for
reproduction and maintenance of the species. These processes are compli-
cated, and the conditions for successful seed germination and seedling
survival are not well understood for many wetland species. For example,
cypress require dryer conditions for seed germination than other wetland
species (cottonwood, ash) but are more flood tolerant as mature trees (FWS
1976).
Monk (1968) and others (Ewel and Mitsch 1978, Teskey and Hinckley 1977)
stress the importance of fire in controlling the natural development of many
plant communities of the Southeast. Lightening associated with thunderstorms
in the Southeast (average 60-80/year in the Gulf coastal states) are a major
source of fire in wetlands. Fire is a selective force which favors the estab-
lishment of fire resistant vegetation (cypress, pine, etc.) or vegetation
adapted to rapid regeneration after fires (grasses) (see 4.2.3 on succes-
sion). Fire is also important in forming depressions in peat wetlands.
During severe drought, peats will readily ignite burning depressions in the
peat surface. These depressions form deep pools when water returns to nor-
mal. Fire also causes important releases and recycling of nutrients in
wetland ecosystems.
The detrital component of wetlands is influenced by vegetation types.
Cypress, pine, cedar and magnolia species have slowly decomposing leaf and
stem parts. Decomposition is slow because of the high amount of refractory
material such as waxes, oils and other organics formed as part of plant
survival mechanism during flooding. The peat found in these wetlands is
different in content and rate of formation than in wetlands dominated by
maples, cottonwoods, ashes, certain grasses and herbs with relatively rapidly
decomposing (labile) leaf and stem parts (litter). Perched bogs have only
atmospheric inputs of nutrients and support vegetation adapted to a low nu-
trient (especially N and P) availability situation. The vegetation in these
wetlands must adapt to limited internal nutrient cycling and water conser-
vation. Riverine wetlands, strands, and minerotrophic wetlands have signi-
ficantly more inputs of nutrients. The vegetation in these wetlands is'
adapted to high and seasonal assimilation. Efficient nutrient cycling is
less critical since qrganic export and productivity is higher in these eco-
systems (Brown 1981).
Many elements of wetland plant ecology are well described in the liter-
ature. Productivity measurements have been made, and successional patterns
have been described (see Sections 4.2.3, 4.2.4). The importance of plants in
nutrient cycles has also been investigated (Prentki et al. 1978, Klopotek
1978, and Simpson 1978). However, a full understanding of the intricate eco-
logical associations of the vegetation with other components of the wetland
ecosystem and among the plants themselves is still lacking. Little is known
about the symbiotic relationships in wetlands or the interaction between
canopy and sub-canopy trees in swamps. Although some authors (Brown 1981)
have noted the impact of grazing insects on wetland productivity, it has not
been quantified. Pollination ecology of wetland is unexplored and trophic
123
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4.2.1 Continued
interactions are not well described. Competition, as it relates to produc-
tivity, ecosystem stability and successional patterns is not well understood.
How these limitations affect the understanding of wetlands processes in
relation to wastewater management will be discussed further in Section 7.0
124
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
4.2.2 Vegetation Types
WETLANDS IN REGION IV ARE CHARACTERIZED BY A VARIETY
OF DOMINANT VEGETATION TYPES
A large variety of vegetation types naturally occurs in
wetlands, including trees, grasses, floating aquatics, and
epiphytes. The presence or absence of an individual plant
type is dependent on its ability to survive and reproduce
in the wetland environment.
A number of factors are responsible for the persistance, development, and
maintenance of vegetation types in the wetland environment. Local climate,
topography, flooding frequency and duration (hydropenod), water velocity and
water quality are a few of the important properties determining types of vege-
tation present in wetlands. Biological factors such as vegetation history
(succession), competition and inherent generic adaptibility to stress also
influence the presence or absence of plant types found in wetlands.
Most plants occuring in wetlands are known as "hydrophytic" plants or
literally "water loving" plants. "Water tolerant" would be a more accurate
description of these plants because to most of these plants, flooding is a
stress factor, decreasing photosynthesis and respiration (Teskey and Hinckley
1977). The varying ability of these plants to tolerate water stress forms a
natural gradient of wetland plant types from mostly tolerant to moderately
tolerant to mostly intolerant.
Plants which adapt to similar sets of environmental variables and hydro-
logic regimes form unique and recognizable plant associations or community
types. These community types may form distinct associations or intergrade
with other plant associations. Classification systems have relied upon these
community types as the basis for differentiation.
Vegetational community types are intimately tied to many common-use terms
describing wetland types. Marshes, for example, are commonly inundated with
water for much of the year and contain grass-sedge-rush community types.
Swamps imply a forest dominated by a variety of hydrophytic trees. The
species of trees present exist along a hydrologic gradient of flooding;
characteristically the more tolerant types (Cypress, gum) are found in the
deeper portions while less tolerant types (Maple, Pine, Willow) are located
in shallower, less frequently flooded areas. Bottomland hardwoods describes
the areas along the less permanently flooded gradient where assorted hard-
woods may predominate. Cypress domes are areas where cypress predominate
under a special hydraulic region. Wet praires, meadows and savannahs are all
common terms which refer to specific ecosystems in which characteristic
vegetation types dominate. Table 2.4 shows the various vegetation types
associated with different classifications of wetlands.
Sub-dominant vegetation types are also in wetlands. These types exploit
unfilled niches within the ecosystem and adapt to life there. Epiphytes are
air plants (bromelliads, orchids) which thrive in the humid swamp forests in
125
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4.2.2 Continued
warmer climates of the southeast. The understory of these swamps may contain
floating aquatic types where light does not permit emergent grasses to
survive.
126
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
4.2.3 Succession
SUCCESSION OF COMMUNITIES IS RELATED TO HYDROPERIOD AND FIRE
Wetland succession describes the process of wetland commun-
Ity development, how It Is maintained, and how It might
change in the future. Certain attributes are charac-
teristic of early wetland successional stages. Others are
associated with later successlonal (climax) wetland
communities.
Wetland succession is important in understanding the life stage of a
wetland community. No natural ecosystems are permanent but are- generally
changing, developing and maturing in response to environmental variables. As
ecosystems mature over perhaps hundreds of years, there is a tendency toward
increased stability, a more complex system, greater total energy flows and
more efficient utilization of resources. The high point of ecosystem
development is called a climax community and is often characterized by the
dominant vegetation at the site. Familiar examples of a climax forest are
the oak-hickory climax on the Appalachians and the California redwoods (Cost-
ing 1956). The southern mixed hardwoods of the Gulf South Atlantic Plain
communities can be either early successional or late successional communities
depending on species composition (Monk 1966). Late successional communities
may exist for prolonged periods of time and are called subclimax communities.
A climax community which is disturbed or degenerates forming a new stable eco-
system is called a disciimax community.
Monk (1968) concluded that cypress-dominated wetlands are subclimax
communities, and bays and mixed hardwood swamps are climax wetlands. Marshes
are most often considered early successional. Pocosins succession is contro-
versial, and these wetlands are thought to be either subclimax, climax or
even disciimax communities maintained by fire. Savannahs and some grass
prairies are also subclimax communities which in periods of declining mois-
ture tend to change into swamp forests. Scrub-bogs with more moisture may
succeed into swamp forests (Barry 1980). Figure 4.2.3 indicates the rela-
tionship between hydroperiod, fire and succession among selected Florida eco-
systems. While not general for the southeast, it is presented to emphasize
the complex interaction of factors which influence succession.
Attributes characteristic of early and late (climax) successional stages
are presented in Table 4.2.3. These attributes are the fabric of an ecolog-
ical system which changes naturally over time. Ecosystem development may be
arrested at certain stages for prolonged periods of time. Critical environ-
mental factors such as fire and flooding often limit ecosystem development.
White cedar bogs are thought to be "fire-climax" communities (Penfound 1952).
When fires are prevalent, they are the climax communities; without fire,
bay-magnolia swamps are climax. Wetland prairies and savannahs are also
fire-dependent climax communities. With less fire or more water they may
change into mixed hardwood swamps. Large tracts of swamps have had the
natural order of succession and development altered by timber cutting and
selective cutting of cypress.
127
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Table 4.2.3. General Attributes of Successional Trends (after Odum 1963).
Ecosystem Characteristic
Plant types and plant
Diversity
Species Composition
Plant size
Total living biomass
Total nonliving Biomass
(peat, etc.)
Stability
Net Productivity
Total Energy Flows
Respiration
Ecological Relationships
Successional Trend (early stage to climax)
Initially increases, stabilizes and may decline
in older stages
Rapidly changes, then is more gradual
Smaller, then larger
Increases
Increases
Increases
Decreases
Increases
Increases
More complex
Source: Odum 1963.
128
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so
UJ
Of
\LX
(A TO
100
aco
SCO
600
100
•too
1000
FftLMETTO
PINE/
PALMETTO
\
V
MARSH
\
\
\
\
\
\
\
SI/TTO.MBUSH
/WILLOW/
CYPRESS
CYPRBS/
HAKDVJOCD
\
HARDWOOD
HAM/AOCK
WILLOW
\r_ CYPRESS
0^0.
CYPRESS/
HARDVJOOD
OPEM WATER
SLOOOH
FLOATING
AND/OR
AQUATICS
f=ONP APPL6
AND/OR.
POP ASH
SLDOC.H
\
\
\
\
\
\
1ZU ISO lto aj0
HVOROPERtOD CDAYS)
270 300
Figure 4.2.3. Relationship between hydroperiod, fire and succession
for selected Florida ecosystems.
Source: Duever et al. 1976.
129
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4.2.3 Continued
Agricultural crops such as wheat and corn are an example of a domesti-
cated early successional ecosystem (Odum 1963). The high net yield of
agriculture relies on the high net productivity characteristic of early
successional ecosystems. Thus, succession can be managed to benefit man.
The integrity and ability of ecosystems to maintain equilibrium are
altered when important successional forces such as fire frequency, water and
nutrients are altered in an ecosystem (Figure 4.2.3), and natural succes-
sional trends are no longer maintained. Just as domesticated early succes-
sional ecosystems are valuable to man (agriculture), mature ecosystems (sub-
climax and climax) have important values in stabilizing water, nutrient and
environmental factors. The importance of succession relative to wastewater
recycling in wetlands is understanding the stability of wetlands, the charac-
teristic rates of production and biomass accumulation in various wetland
types, and the integrity of various wetland successional types and their
importance to man.
130
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
4.2.4 Productivity
SOUTHEASTERN WETLANDS EXHIBIT WIDE RANGE OF PRODUCTIVITY
Natural rates of production in wetlands vary from less
than 200 to over 1600 g/m2/yr. Tidal freshwater wetlands
and riverine swamps exhibit the highest productivity and
are among the most productive ecosystems in the world.
Productivity is governed by many interacting factors and
appears to be controlled by nutrients and hydroperiod
stress in wetlands. Productivity is important in Indexing
the assimilative capacity of wetlands.
The primary productivity of wetlands is usually the measure of the rate
of organic matter production by autotrophs (mostly plants). It is an
important index to the activity of a system. Primary productivity reflects
the ability and efficiency of wetlands in utilizing available nutrients and
sunlight to produce organic matter. Some wetlands are potentially among the
most productive ecosystems in the world (Odum 1963). Since many factors
govern the productivity in wetlands, a wide range of productivity has been
observed. Productivity is limited by genetic biotic potential, sunlight, and
nutrient availability and other locally important stress factors.
Primary productivity is expressed as either gross primary productivity
(GPP) or as net primary productivity (NPP). The GPP is the total amount of
organic matter fixed including that used up by respiration. NPP is the
organic matter stored in plant tissues in excess of respiration. Net produc-
tion represents food potentially available to heterotrophs and for export.
Under favorable conditions of light, moisture and nutrients, net production
is high (90 percent of GPP). Under many conditions in nature, stress results
in higher respiratory losses, and net production may be low.
A wide range of production has been reported for wetlands (Gosselink and
Turner 1978). Mitsch and Ewel (1979) have hypothesized generalized produc-
tivity in forested wetlands. This emphasizes the importance of hydroperiod
stress and productivity. Brown (1981) showed the importance of both hydro-
period and nutrients in determining productivity in swamp forests. She
suggested that only those forested wetlands that receive nutrient subsidies
either naturally from flooding rivers or artificially from sewage effluent
are highly productive.
Brown's (1981) results indicate that increasing nutrient inputs (via
hydrologic or man-induced additions) resulted in increased gross primary pro-
uctivity, net productivity and plant respiration. The gross primary produc-
tivity measurements were more sensitive to changes in phosphorus input than
other factors studied. These trends indicate that increased phosphorus
inflow increases the rate at which sunlight fixes C02 into organic matter
(gross primary productivity) but at a correspondingly higher cost (higher
plant respiration). This counteractive effect results in a leveling of bio-
mass production and net primary productivity instead of dramatic increases
with greater phosphorus inputs. Another observation made by Brown (1981) was
131
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4.2.4 Continued
that with increasing phosphorus input, a proportionally less percentage of
total phosphorus taken up by biomass is allocated to fruit and leaf
production, indicating that excess phosphorus is stored in woody biomass.
Still and slow-flowing wetlands not receiving effluents have compar-
atively less production than flowing water (riverine) wetlands because of
lower nutrient input (Brown 1981). The addition of sewage effluent will
increase productivity by increasing available nutrient, but, as is evident in
Figure 4.2.4, hydroperiod stress may constrain this increase.
Productivity and respiration may also be measured on the ecosystem level
yielding total community production and total community respiration. The P/R
rate of 1 reflects a steady state community (Odum 1963). If production and
respiration are not equal (P/R greater or less than 1), with the result that
organic matter is either accumulated or depleted, the community is expected
to change by the process of ecological succession (see Section 4.2.3). Suc-
cession may proceed either from an extremely autotrophic state (RP) toward a new condition in with P=R (Odum
1963). Wetlands vary in their successional stages (see Section 4.2.3). Wet-
lands assimilating highly organic sewage effluent are an example of the het-
erotrophic state, where organic matter is used up faster than it is produced.
Peat-forming wetlands result from storage of large amounts of carbon pro-
duction (i.e., high annual productivity). Riverine swamps and marshes export
substantial amounts of organic matter to estuaries, which influence fish and
shellfish harvests. Some wetlands (scrub cypress) are low in productivity,
and peat layers may be minimal.
Seasonal differences as well as diurnal differences affect productivity.
Winter typically causes lower productivity and subsequently lower nutrient
uptake. The understory of swamp forests also has limited productivity
because of shading effects. However, in the early spring, algae may tempo-
rarily dominate productivity in deciduous forests before leaves reappear
(Brinson et al. 1980).
These temporal and wetland type variations in productivity are important
in understanding and managing wetlands for nutrient assimilation. Especially
important from an ecological viewpoint is limiting stress on a wetland that
would significantly change the quantity and the quality of organic export,
thus affecting downstream communities dependent on wetlands exports.
132
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o
Q
O
DC
Q_
LU
ALL
TREES
CYPRESS
CYPRESS-PINE
CYPRESS-
HARDWOOD
CYPRESS-
TUPELO
PURE STAND
OF CYPRESS
DRYf-
DRAINAGE CONDITIONS
->WET
INCREASING DIFFERENCE BETWEEN WET AND DRY SEASONS
- CYPRESS DOME WITH ADDED
WASTEWATER OR GROUNDWATER
Figure 4.2.4. Hypothesized relationship between hydroperiod and net
productivity for several wetland forests.
Source: Mitsh and Ewel. 1979.
133
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4.0 NATURAL WETLAND CHARACTERISTICS
4.2 Vegetation
4.2.5 Rare and Landmark Wetlands of Region IV
WHITE CEDAR BOGS, OTHER WETLANDS MARKED FOR PRESERVATION
All wetlands have intrinsic natural value. Several
wetland types must be given special protection due to
their special ranges, uniqueness, scientific or cultural
value.
The wetland resources of the U.S. have declined dramatically since the
turn of the century. It has been estimated that over 40 million acres have
been lost since then. The consequences of wetlands destruction include loss
of flood storage, erosion control, wildlife production, and habitat and gene-
tic diversity. The most significant source of encroachment on wetlands has
been channelization activities and agricultural conversions. The use of wet-
lands for wastewater recycling does not fit into the above categories, but,
for some wetlands, this practice may not be appropriate.
The wetlands described in this section are those which are outstanding in
some regard. They deserve special consideration because of their rarity,
uniqueness of habitat, location, special endemic species, and scientific or
cultural values. As a result, they are less preferrable for use in a
wastewater management system.
An extensive survey of unique wetlands of the United States was published
in 1975 by the National Park Service (NPS) (see Section 2.3). The purpose of
this report was to identify wetlands which may qualify as national landmarks.
Wetlands were selected for their expanse, uniqueness, scientific and wildlife
value. A descriptive listing of the landmark wetland types in each Region IV
state is presented in Table 4.2.5-a. The NPS publication, "Inland Wetlands
of the U.S." (Goodwin and Niering 1975), contains a complete listing and
description of the wetland landmarks.
The group of wetlands listed by Goodwin and Niering (1975) is by no means
a complete listing of rare and sensitive systems important in maintaining our
wetland heritage. Wastewater recycling is a more sensitive issue regarding
these wetlands since the possibility exists that some characteristic of the
natural wetland may be altered (see Section 7.1.2). Identification of the
uniqueness and value of a wetland is not a simple task (Golet 1978). Local
authorities are best consulted to identify unique or unusual wetlands. South
Carolina, for example, has a series of map overlays which identify wetlands
in each county and key the distribution of rare and endangered plants to that
wetland map (Phillips 1982).
Other wetland types which are noted for their rarity and scientific value
on a region-wide basis are the white cedar bogs and the Carolina bays. The
limestone sag ponds are wetlands with a limited regional distribution. Pen-
found (1952) mentions the eight minor freshwater swamps and five minor
freshwater marshes (Table 4.2.5-b) which should be considered limited in dis-
tribution and possibly unique.
134
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Table 4.2.5-a. Landmark Wetlands of Region IV
Areas
State Reported Description
Alabama 3
Florida 11
Georgia 13
Kentucky 2
Mississippi 3
North 1
Carolina
South
Carolina
Tennessee
Riverine swamps, floodplain forest, sloughs, beaver
ponds, delta wetlands (fresh-saline, forest-marsh
transitions).
Swamp forests, wet prairies, tree islands, scrub
cypress, riverine headwaters.
Coastal and Piedmont areas dominated by Southern River
Swamps. Lack data on New Ridge Valley section of state.
Sagpond areas unique.
Seasonally flooded river bottoms of Ohio and Mississippi
Rivers. Sloughs. Include many scattered small sinks.
Extensive river bottom swamps. Southwesterly extension
of white cedar at Juniper Swamp.
Long Hope Creek spruce bog of interest, numerous pocosins
and bottomland swamps (riverine) exist, but not yet included
as "Landmark" wetlands.
Extensive bottomland forest: The Congaree, Fourhole swamp,
are outstanding examples. Channelization is a major
threat.
All three major wetland types (marshes, bogs, swamps)
represented. Bogs have specific scientific value in
pollen records. Limestone marsh sinks have special
habitat value. Some very diverse wetlands areas exist.
The rare bluewinged teal is associated with these
wetlands.
Source: Goodwin and Niering 1975.
135
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Table 4.2.5-b.
Swamps
Minor Marsh and Swamp Types Discussed in Penfound (1952).
Description
Water Elm
Swamp Privet
Pop Ash
Green Ash
Mayhaw
Canebrake
Custard Apple
Palm Savannahs
Planera aquatica, Forestiera acuminata form distinctive swamp
types within cypress-gum swamps. May occur in deeper waters
than cypress.
Fraxinus caroliniana: may occur in pure stands in Florida
ponds.
Fraxinus Pennsylvania: may occur in pure stands exhibiting
buttressed bases in shallow ponds.
Crataegus aestivalis ponds of coastal plain.
Arundinaria gigantea: covers large open areas in Dismal
Swamp; results after cutting in both blackgum, white cedar
swamps, spreads rapidly by underground stems.
Annona glabra now almost extinct, best developed near Lake
Okeechobee.
Marshes
Description
Flag Marshes
Prairies
Sphagnum spp.
Woodwardia
virginica
Scirpus -
Erianthus
Bur-reed
Marsh
Pontederia cordata, Sagittaria lancifolia. Thalia dealbata.
common in shallow ponds and sloughs, mostly in sandy areas of
Florida.
Similar to above with more diversified plant composition,
"pseudo marshes" nearly devoid of sedges, grasses, rushes,
common as medial stage of hyacinths mats into marshes.
In open areas of Dismal Swamp, shallow areas of Okeefenokee
Swamp, elsewhere.
This association of Scirpus cyperinus and Erianthus saccha-
roides major dominates in cutover areas of Dismal Swamp,
elsewhere.
Sparganium americanum dominated community in openings of swamp
forests.
Source: Penfound 1952.
136
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
ALL ECOSYSTEM PROCESSES IN A WETLAND ARE DISTINCTLY AND
SIGNIFICANTLY INFLUENCED BY HYDROLOGY
The natural integrator of most wetland ecosystem processes
Is hydrology. Understanding of hydrologic processes and
their relation to effluent disposal can only be achieved
through studying individual hydrologic processes amalga-
mated in the water budget. Each wetland is unique, and
the receipt and deposition of water are directly
influenced by wetland physical parameters.
An understanding of hydrologic processes in a wetland ecosystem is
necessary if wastewater management considerations are to be evaluated
properly. Hydrologic budgeting has considerable value as an index to the
hydrologic process; it is a means of isolating and estimating individual flow
and storage components that influence physical and biological wetland activi-
ties. Wetlands can receive water inputs from precipitation, overland flow
and groundwater, but some wetlands receive only precipitation. Evapotrans-
piration, groundwater recharge and runoff constitute the primary water
outputs.
Each wetland is unique in terms of location, morphology and other phy-
sical parameters that influence the receipt and deposition of water.
Catchment size and morphometry, antecedent moisture, infiltration capacity
and climatic fluctuations function as control mechanisms for inundation
frequency and duration. The temporal characteristics of inundation determine
vegetation distribution, diversity, and flows and regulate filtration pro-
cesses. Wetlands typically reduce peak flows and regulate filtration
processes. Wetlands typically reduce peak discharge and total stormflow
volume because short-term detention storage is greater, and overland flow
through a wetland frequently occurs as sheetflow.
Storage fluctuations in wetland ecosystems are closely linked to seasonal
variations in rainfall, evapotranspiration, water table level and soil mois-
ture. Groundwater is the major component of storage in a wetland basin and
recnarge and discharge processes depend on whether the wetland is isolated
Trom underlying aquifers.
137
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.1 Hydrologic Budgeting
THE HYDROLOGIC BUDGET REPRESENTS THE NET EFFECT OF ALL PROCESSES THAT
INFLUENCE THE HYDROLOGIC CYCLE OF A WETLAND ECOSYSTEM
Hydrologic budgeting has considerable practical value as
an Index to the wetland hydrologic process. The dominant
components In a wetland budget Include precipitation and
surface and subsurface flows as inputs; evapotranspiration
and surface and subsurface flows as outputs. The volume
of precipitation input is primarily a function of canopy
development, storm composition and prevailing climate (Lee
1980). Surface water inputs and outputs usually occur as
sheetflow. Variations in precipitation timing affect
total water yield, and more studies are needed before a
clear correlation between precipitation timing and
resulting streamflow is established. The importance of
groundwater in the budget depends on the participation of
the water table aquifer in recharge and discharge
processes. Evapotranspiration is dependent on net
radiation, wind speed, total availability of water and
vapor pressure gradients.
Hydrologic budgeting is primarily used to isolate and estimate individual
flow and storage components and to check on the accuracy of observational
data. The long-term average water budget for a wetland catchment appears in
various forms (Carter et al. 1978, Heimburg 1976, Boelter and Verry 1977).
During periods of drying (storage decrease) the budget can be represented as
P + Qi + Gi + S = Et + Qo + Go
Where P is precipitation, Qi and Qo are surface water inflows and outflows
respectively, Et is evapotranspiration, S is storage and Gi and Go are
corresponding groundwater flows.
Figure 4.3.1 is a graphic representation of the dominant components of a
hydrologic budget that can be identified for planning purposes. It
differentiates clearly between those components that involve rates of
movement (hexagonal boxes) and those that involve storage (rectangular
boxes). The usual assumptions associated with budgeting are that 1)
subsurface leakage into the catchment exists, 2) underflow and deep
percolation from the catchment are negligible and 3) catchment storage is
only subject to random or seasonal fluctuations. None of these assumptions
is totally accurate, especially as applied to wetland catchments where
hydrologic properties are not well understood and are difficult to analyze
quantitatively. Nevertheless, budgeting has considerable practical value as
an index to the wetland hydrologic process (Lonard et al. 1981). A brief
description of the major water budget components is presented below.
138
-------
(Evopotronspirotlon) (Precipitation)-
interception
throughfall^>
Interception
storage
-xC overland flow
infiltration
\r
Unsaturated
soil moisture
storage
<^groundwoter rechorge^>
Saturated
groundwater
storage
Deep percolation
interflow
boseflow
Figure 4.3.1. Systems diagram of the dominant components of a hydrologic
budget.
Source: Freeze and Cherry. 1979.
139
-------
4.3.1 Continued
Precipitation
The volume of precipitation input in most Southeastern wetlands is a func-
tion of canopy development, storm composition and prevailing climate (Lee
1980). Swamps are wooded ecosystems with well developed canopies; precipi-
tation volume here is limited by canopy interception and subsequent canopy
storage. Open marshes are generally covered with non-woody vegetation, and
precipitation volume is limited mainly by climatic factors such as
temperature and global radiation.
In several wetland types precipitation is the primary input, and mea-
surement accuracy is critical. These wetlands represent restricted hydro-
logic regimes in the sense that they are isolated from groundwaters and
receive no upland surface drainage. The central area of a perched bog
represents the most restricted hydrologic wetland (Verry and Boelter 1978,
Gosselink and Turner 1978). Pocosins in North Carolina are also typical of
this situation. Included to a lesser degree is the Okeefenokee Swamp in
Georgia and the Great Dismal Swamp in Virginia and North Carolina; these
swamps are generally isolated from groundwater sources but do receive some
upland surface runoff (Kuenzler et al. 1980, Gosselink and Turner 1978).
Precipitation timing has a bearing on wetlands being considered for efflu-
ent disposal. For most wetlands the timing of precipitation is dependent on
seasonal variations. During periods of greatest seasonal rainfall the maxi-
mum effluent loading capacity could be exceeded in some localities. The
timing and quantities of extreme rain events (hurricanes, etc.) need to be
considered in engineering planning for wetlands used in wastewater manage-
ment. Heimburg (1976) concluded that rainfall distribution in Florida
cypress domes could limit wastewater loading rates during both the winter and
summer wet season. High rainfall may mean lower nutrient concentrations and
rapid export of effluents without natural treatment.
Surface Water
Total water yield for a catchment is primarily determined by atmospheric
factors, catchment parameters and specific wetland influences. In small wet-
lands, considerable variation in water yield from year to year may ocicur, but
the data base characterizing variations is largely incomplete (Carter et al.
1978, Daniel 1981). In general, a positive correlation exists between annual
precipitation and water yield. Deviations from this norm may reflect
carry-over effects of alternating wet and dry years, differences in catchment
storage at the beginning of a year and variations in precipitation timing.
More studies are needed before a clear correlation between annual precipi-
tation fluctuations and resulting streamflow is established. Increases in
solar and net radiation and air and surface temperatures result in decreases
in water yield. Atmospheric humidity is positively correlated with water
yield.
Water yield is more than an atmospheric phenomenon, and important dif-
ferences in water yield from wetlands result from catchment location, relief,
area, shape and substrata. At present no clear relationship exists between
water yield and catchment area in cypress domes (Heimburg 1976). Daniel
140
-------
4.3.1 Continued
(1981) concluded that flat topography contributed to low rates of surface
runoff; in raised swamps and perched bogs, surface runoff was negligible.
Determination of specific wetland influences on water yield is important
because of the existing variations in Southeastern wetland types. Gooselink
and Turner (1978) developed a system that characterized wetlands, in part by
their source of surface water inputs and outputs. Perched bogs were class-
ified as having no surface inflow or outflow. Sunken minerotrophic fens were
classified as having a very slow surface water input and no downstream run-
off. Lotic fens and swamps and riverines were classified as having signi-
ficant surface water inputs and downstream ouputs. Surface water inflows to
an individual wetland are related to many local physical and environmental
factors. Factors affecting inflows include, orientation and size of wetland
surrounding soil characteristics and land use patterns, and storm charac-
teristics. Riverine wetlands (bottomland hardwoods, etc.) may be extensively
flooded as a response to upstream storms. Surface water inflows carry
nutrient and sediment loads that influence the productivity and soil
characteristics of wetlands. The environmental factors underlying these
causal relationships should be quantified as wastewater management options
are considered.
Groundwater
The importance of groundwater in the water budget depends on the parti-
cipation of water table aquifers in recharge and discharge processes. Fens
maintain contact with water table aquifers. The relative inputs and outputs
of water are variable, but groundwater inputs are significant (Boelter 1978).
bwamps and marshes may also have significant groundwater inputs. In well
developed peatlands, groundwater can enter the ecosystem from the uphill
edges or through amorphous groundwater channels Boelter and Verrv 1977-
Kuenzler et al. 1980; Daniel 1981). Wang and Heimburg (1976) estimated infil-
tration, percolation and groundwater flows for two cypress domes in north
Central Florida using standard techniques. One cypress dome served as both a
discharge and recharge area. Another dome served only as a recharge area.
Evapotranspiration
Evapotranspirationi for a given wetland depends on net radiation, wind
speed, total availability of water and vapor pressure gradients. Wetlands
with well developed canopies reduce direct evaporation by insulating the soil
against radiant heating and wind, but they overcompensate for this during
active growing seasons by drawing moisture from subsurface areas. Phreato-
phytes draw water directly from the saturated zone or its capillary fringe.
Once the water table drops be1ow the roQt ^^ evapotpansp1pat1 ^
arrpUdomn^teKr anhd Kerry,19u77; Daniel 1981)« In Poland ecosystems that
are dominated by shrubs and hedges, evapotranspiration tends to be greater
than in bottomland hardwood swamps because surface winds are higher and a
ofeaeVTDotr°r^ °J.tran.sP1r1n9 P]ants exists (Daniel 1981). Maximum values
of evapotranspiration in cypress domes generally occur during May, and
minimum values occur during February (Heimburg 1976).
141
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.2 Inundation: Frequency and Duration
DURATION AND FREQUENCY OF INUNDATION IS FIXED BY REGIONAL CLIMATE
AND WETLAND PHYSICAL CHARACTERISTICS
Both duration and frequency of flooding in a wetland
ecosystem are fixed to a large extent by regional climate.
Other factors, however, play an important role in deter-
mining the hydrologic response of a particular wetland to
runoff-producing storm events. The primary determinants
include catchment size, antecedent moisture, infiltration
capacity and climatic fluctuations.
Catchment Size
In wetlands associated with large catchments, the time of concentration
is greater, and intense rainfall is less likely to occur over the entire
area. As area increases, discharge per unit area decreases at high flows.
However, both discharge and precipitation depths are usually greater at
higher elevations. Smaller catchments that are restricted to more upland
areas have greater discharges and associated peaks.
Antecedent Moisture
Increased flooding occurs when antecedent moisture conditions are
greatest (Carter et al. 1978; Verry and Boelter 1978). When the water table
is high, available soil storage is reduced and the same phenomenon occurs.
Water table fluctuations are influenced by the hydraulic properties of the
soil and underlying strata, the seasonal pattern of evapotranspiration and
fluxes in the supply of water to underlying aquifers (Daniel 1981). Perched
bogs exhibit greater water table fluctuations because of the seasonal influ-
ences of precipitation and evapotranspiration. Bogs fed by groundwater or
riverine systems have a more uniform hydrologic regime, and water table
fluctuations are less pronounced (Verry and Boelter 1978; Brinson et al.
1981).
Infiltration Capacity
Infiltration capacity is important because it determines the downward
movement of water through the surface of mineral or organic soil. It is
affected by soil physical properties and moisture content, permeability and
soil microclimate. Little has been done in making comparisons of infiltra-
tion capacities for different wetland ecosystems. In peats infiltration is
inversely proportional to the degree of decomposition (see Section 4.1.2 on
Soils). Where precipitation is not strongly seasonal, maximum infiltration
rates occur toward the end of the growing season. The dynamic aspects of
infiltration in relation to inundation frequency and duration cannot be fully
understood without further studies. Existing studies cover bogs (Boelter and
Verry 1977; Verry and Boelter 1978) and cypress domes (Heimburg 1976).
142
-------
4.3.2 Continued
Climatic Fluctuations
The frequency and duration of inundation is closely associated with
seasonal climatic fluctuations. The greatest portion of annual flow from
perched bogs occurs in early spring when rainfall exceeds evapotranspiration,
and antecedent moisture is at a maximum. Most studies regarding cypress
domes indicate that storm events must exceed 0.4 inches before surface flow
occurs (Heimburg 1976). In riverine swamps inundation is greatest during
late winter and early spring when water storage capacity and evapotrans-
piration rates are minimal (Brinson et al. 1981). This, however may not be
true of all Region IV wetlands where, for example, a dry season may predom-
inate during the winter (Florida).
143
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.2 Inundation: Frequency and Duration
4.3.2.1 Relationship Between Flooding, Plants and Nutrients
THE EXISTENCE OF PLANTS AND THE AVAILABILITY OF NUTRIENTS DEPEND
ON INUNDATION FREQUENCY AND DURATION
The duration and frequency of flooding are dominant
factors responsible for plant species diversity, distri-
bution and growth rate. The duration of inundation is the
dominant factor influencing species distribution. The
seasonal timing and the energy associated with flood
waters affect the input, retention and export of
nutrients.
The diversity, distribution, and growth rate of wetland vegetation depend
to a great extent on the duration and frequency of inundation. Wetland
vegetation in turn affects flooding by retarding surface water flows and
controlling water inputs through canopy interception and evapotranspiration.
The relationship between the distribution of wetland vegetation and flooding
duration is so distinct that flooding characteristics for a given site can be
evaluated by observation of species composition (Bedinger 1978; Bedinger
1980). Duever et al. (1977) related flood duration with six habitat types in
Corkscrew Swamp, Florida. Carter et al. (1978) list numerous studies that
assess the long-range effects of inundation frequency and duration on species
growth rate, propagation and distribution for different wetland ecosystems.
The timing of inundation and the energy associated with flood waters
affect the input, retention and export of nutrients. The physical configu-
ration of a wetland area is related to the inputs of nutrients and water
(Figure 4.3.2.1). Flood water provides a vehicle for the movement of
dissolved and suspended solids. This movement provides a greater avail-
ability of micro-nutrients for plant growth; thus, plant growth is a function
of discharge velocity, As velocity increases so does sediment input, and
plant growth is accelerated. Nutrient availability is also a function of the
source of water input. Ombrotrophic bogs, for example, are nutrient poor
because the only input is rainwater. River and floodplain ecosystems, in
contrast, are nutrient rich because water inputs include rainwater, stream-
flow and overhead flow (Figure 4.3.2.1). The abundance of nutrients usually
associated with fens results from nutrient-rich groundwater supplies.
Gosselink and Turner (1978) give an excellent review of inundation effects on
nutrient availability.
144
-------
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.2 Inundation: Frequency and Duration
4.3.2.2 Filtration
HYDROLOGY EITHER LIMITS OR ENHANCES FILTRATION
The duration and depth of Inundation regulates filtration
processes. This effect occurs primarily because water in
wetlands travels mainly by sheetflow.
Vegetation type and density and soil type and physical properties play a
major role in a wetland1s ability to filter suspended matter. Direct
hydrologic processes, however, significantly affect the degree of filtration
through decreased flow rates. Decreased flows primarily occur because
overland flow in many wetland types is sheetflow. Sheetflow is associated
with decreased carrying power and fallout of suspended particles. Little
quantitative data on this process exist (Boto and Patrick 1978); therefore,
more studies are needed to determine the extent to which the duration and
frequency of inundation, along with vegetation, regulate filtration. The
amount of suspended sediment present in a wetland also impacts filtration and
subsequent removal of nutrients and toxins associated with wastewater
effluent. Filtration is an important mechanism for renovating water within a
wetland.
146
-------
4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.3 Buffering
THE DEGREE OF FLOOD REDUCTION DEPENDS ON TOPOGRAPHY AND
PERCENT SURFACE WATER AREA
The ability of a wetland to attenuate flood peaks and
storm flows are associated with wetlands having restricted
outlets and flat topography. Wetlands with greater
surface water area have greater detention storage and
significantly lower flood peaks. Evapotranspiration of
surface water reduces baseflow in wetlands during low flow
periods.
An abundance of evidence exists supporting the observation that peak
discharge is significantly less in wetlands than in other ecosystems (Carter
et al. 1978, Boelter 1978, Verry and Boelter 1978). Flood reduction depends
on the percentage of surface water in the catchment and topography. Wetlands
primarily attenuate flood peaks (Figure 4.3.3) and storm flow volumes by
temporarily storing surface water. This storage occurs because most wetlands
have restricted outlets and are located in flat topographic regions. Basins
with a greater percentage of water surface area have greater short term deten-
tion storage and thus reduced flood peaks. Storage of water in upper soil
horizons is typically greater in areas of flat topography. This capacity
also works to reduce flood peaks. The cypress domes of Florida, the Okeefe-
nokee Swamp of Georgia and the Great Dismal Swamp of Virginia and North
Carolina have long residence times for surface waters thus reducing poten-
tially high peak discharges (Daniel 1981, Boelter and Verry 1977). The
suppression of base flow also occurs in wetlands during low flow periods
because evaporation of surface water is significant.
147
-------
CO
Q
LLI
o
DC
LL
LLI
111
O
DC
O
CO
o
RAINFALL
WETLANDS
NO WETLANDS
TIME
Figure 4.3.3. Graphic presentation of a floodplain's ability to attenuate
discharge rate and peak flows with and without wetlands.
Source: Odum 1978.
148
-------
4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.4 Storage
STORAGE IN MOST WETLANDS OCCURS AS GROUNDWATER, SURFACE WATER AND
SOIL MOISTURE
Groundwater Is the major component of wetland storage, and
fluctuations in groundwater storage relate to precipita-
tion and evapotranspiration. Surface storage fluctuates
in response to infiltration. Soil moisture storage
depends on soil type, water table level, degree of
decomposition and microclimate.
Groundwater
Groundwater is the largest component of storage in a wetland basin. It
fluctuates slowly in response to precipitation and percolation inflow and to
seepage outflow. Average seasonal variations in groundwater storage are
highly correlated with the climatic balance between precipitation and evapo-
transpiration. Groundwater depletion lags behind increases in evapotranspira-
tion. Topography can also influence the total volume of water stored as
groundwater. Flat terrain contributes to low rates of surface runoff and
greater opportunities for downward movement of water.
Surface Storage
Surface storage increases or decreases in response to infiltration.
Water in a wetland ecosystem cannot continue to infiltrate unless percolation
removes stored water in the water table aquifer. Surface storage is gen-
erally greatest in wetlands that function as a discharge area (Wang and
Heimburg 1976, Heimburg 1976). The physical properties of the zone of
aeration cause variations in this generalization by controlling subsurface
storage and the direction of groundwater flow; so it is important to charac-
terize soil moisture storage by estimating soil bulk density, porosity and
moisture potential.
Soil Moisture
The storage capacity of wetland soils is clearly related to soil type,
water table level, degree of decomposition and climatic factors. Specific
retention, the fractional volume of water held against the force of gravity,
is greatest in clay and smallest in solid limestone. Fibric peats have a
high hydraulic conductivity because decomposition is less pronounced.
Reduced water storage results as water easily passes into the water table
aquifer. Soil moisture is a dynamic property of soils because water table
fluctuations control the total volume of pore space available for storage.
Storage of water in soil also responds to fluctuations in evapotranspiration
because vegetation regulates insulation and transpiration processes.
149
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4.0 NATURAL WETLAND CHARACTERISTICS
4.3 Hydrology
4.3.5 Groundwater Recharge
GROUNDWATER RECHARGE FOR A GIVEN WETLAND DEPENDS ON ITS INTER-CONNECTION
WITH UNDERLYING AQUIFERS
Pathways associated with groundwater recharge include 1)
infiltration from the surface through the zone of
aeration, 2) vertical movement of water through streambeds
and 3) seepage through confining beds. Recharge is
substantially lower from wetlands where an impermeable
clay interface separates the wetland from the underlying
aquifer.
Groundwater recharge depends on wetland type. In perched bogs, ground-
water recharge is negligible because usually no connection exists with
underlying aquifers (Verry and Boelter 1978, Boelter and Verry 1977). Swamps
and marshes adjacent to and drained by surface waters may or may not be
recharge areas. Kuenzler et al . (1980) briefly discusses requirements needed
for recharge to occur in these wetlands. Mineotrophic bogs mainly serve as
discharge areas. Heimburg (1976) concluded that cypress domes can serve as
recharge areas, but this depends on the existence of an impermeable clay
interface.
150
-------
4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
INTERRELATED PARAMETERS CREATE COMPLEX WATER QUALITY IN WETLANDS
Dissolved oxygen, pH, nutrients, metals and bacteria are
Interrelated parameters In wetlands and result In a
complex water quality system. Impacts to one parameter
may have further repercussions on other parameters. In
most cases, water quality parameters are site specific,
which limits the establishment of uniform effluent
limitations and loading rates for wetland discharges.
Dissolved oxygen (DO) values consistently below saturation have been
reported for many wetlands in the Southeast. Low DO levels in humic swamp
waters are attributed to heterotrophic respiration of organic matter, decom-
position, and a chemical process of oxygen consumption in the presence of
iron. DO levels also vary with water depth, season and time of day. Dis-
solved oxygen levels affect the release of nutrients, microbial respiration
and organic matter decomposition. Increased organic loadings in wetlands,
such as with the addition of wastewater, will alter the prevailing DO regime
and require the flora and fauna of wetlands to adapt to a larger range of DO.
Wetlands are also typically acidic with pH levels less than 7.0. This
low pH, associated with organic acids leached from wetland vegetation
significantly impacts the species composition and water chemistry of closed
wetland systems. Wetland systems that are well buffered tend to maintain a
relatively constant pH; wetland systems that are not well buffered are
generally those with high internal sources of acidity and few outsidQ sources
of alkalinity. The impact of wastewater disposal is dependent to some extent
on the buffering capacity inherent in the wetlands and the composition of the
wastewater.
Nutrient cycling may be the most important yet complex and least under-
stood wetland characteristic. Nutrients (nitrogen, phosphorus, carbon and
sulfur) and the dissolved constituents move through wetlands in association
with the hydrologic regime and atmospheric diffusions. The path by which
nutrients move through wetlands is altered by long-term uptake, internal
cycling, dilution and diffusion. Nutrient retention or release in a wetland
is site-specific and dependent upon litter fall patterns, rate of litter
decay, internal chemistry, substrate composition, seasonality, hydrology and
other locally important ecological parameters. The rate of nitrogen, carbon
and sulfur transformations is further modified by bacterial action. An under-
standing of the specific nutrient cycling characteristics is essential in
order to assess the impacts of increased nutrient loadings and altered pat-
terns of nutrient cycling associated with wastewater disposal.
The fate and impact of heavy metals and other toxins in wetlands is
particularly important because of their potentially adverse effects. Heavy
metals entering wetland ecosystems may be transported through active plant or
animal uptake, passive movement to surface or groundwaters, or immobilized
into the soil matrix by physical or chemical forces (Kadlec and Kadlec 1978).
Generally, studies of heavy metals in wetlands receiving wastewater effluent
151
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4.4 Continued
heavy metals in wetlands receiving wastewater effluent have been incon-
clusive; however, it is undoubtedly understood that many aquatic plants and
animals can assimilate heavy metals from the water. Potential loading limits
for heavy metals are related to levels acceptable for potential plant and
animal uptake, the rate of metal accretion and the degree of burial in the
sediments, and the additional uses of the wetland area and potential for
eventual human or animal exposure.
Specialized groups of bacteria also play a vital role in wetland water
quality by regulating nutrient cycling, water chemistry and decomposing
endemic and introduced organic materials. Certain endogenous and exogenous
bacteria can directly or indirectly threaten human health, and wastewater
introduced into wetlands may potentiate this problem.
Various water quality parameters are discussed further in the following
subsections.
152
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.1 Dissolved Oxygen
LOW DISSOLVED OXYGEN CHARACTERISTIC OF SHADED SWAMPS
Shaded swamp forests are characteristically low in
dissolved oxygen, consistently below saturation but
usually not anoxic. Marshes may have high dally fluc-
tuations In oxygen. In the summer they may become super-
saturated with oxygen and anaerobic in the same day.
Dissolved oxygen (DO) is an important chemical parameter of natural
waters. It is a measure of the amount of oxygen dissolved in the water and
is most often expressed in milligrams per liter (mg/1). The saturation value
of dissolved oxygen is strongly dependent on temperature and salinity. The
higher the temperature and salinity, the lower the saturation value for
oxygen.
Low DO values consistently below saturation have been reported for
several humic (tea-colored) swamps and bogs in the Southeast. Dierburg and
Brezonik (1980) reported a seasonal range of DO in an undisturbed cypress
dome of 0.25 mg/1 to 6.75 mg/1 with a bimonthly average value of 2.03 mg/1.
Beck (1974) noted that the DO in the Satilla River was reduced when
influenced by swamp waters. A reduction in DO content from 70-80 percent
saturation to 12-35 percent saturation was observed when the White Nite River
flowed through a swamp (Tailings 1957).
Low oxygen in humic swamp waters is attributed to several processes. Tra-
ditionally, heterotrophic respiration of organic matter has been noted for
consuming available oxygen in water. Intense decomposition can cause severe
oxygen deficits and create anoxic conditions (Wetzel 1975). There is also a
chemical process of oxygen consumption proposed in the presence of iron (Fe)
(Miles 1977). A catalytic cycle of Fe II and Fe III may reduce organics and
consume oxygen, creating an active oxygen sink in wetlands.
The DO will often vary with depth of water or peat, generally declining
with depth. The amount of DO is an important factor in determining the
biotic community and type of decomposition by microorganisms. When oxygen
becomes limiting in the roots (less than 1 mg/1), plants must develop an
alternate means of acquiring oxygen. Benthic invertebrates and fish are also
dependent on available oxygen. In well oxygenated marshes and swamps,
aerobic (with oxygen) respiration will occur. When oxygen is limiting,
anaerobic organisms dominate, and decomposition will take place at a much
slower rate.
A large daily variation in DO is commonly observed in marsh waters or in
those wetlands with a dense growth of aquatic or emergent plants (cattail,
duckweed, etc.). The photosynthetic activity of the plants, especially
during the summer, releases a large amount of oxygen into the water. The
high temperatures lower the saturation value for oxygen and the water is
often supersaturated, reported by Schwegler (1977) to exceed 200 percent
153
-------
4.4.1 Continued
saturation. A high respiration may drive down the DO to extremely low values
at night (less than 0.1 mg/1) as reported by Schwegler (1977). These highly
productive wetlands have plants, animals and microflora adapted to great
daily fluctuations in DO. These fluctuations are not as pronounced 1n the
winter months since respiration and photosynthetic rates are lower, and the
cooler temperatures allow greater DO retention in the winter.
Dissolved oxygen at the sediment-water interface controls the release of
important nutrients such as phosphorus (Wetzel 1975). Though forested wet-
lands are usually low in DO (Dierburg and Brezonik 1980), they are not consis-
tently anoxic. When anoxic conditions do occur (usually in the summer
months), phosphorus may be released from the sediments in which it is usually
bound. In the anoxic environment micronutrients tend to be more readily
available, and toxic materials such as hydrogen sulfide accumulate in the
substrate (Gosselink and Turner 1978)*. Low DO is also an essential condi-
tion for certain phases of the nitrogen, carbon and sulfur cycles (see
Section 4.5).
The profound influence DO exerts on microbial respiration directly
controls the rate and completeness of organic matter decomposition. Thus the
rate of peat formation and the composition of the peat are controlled by DO
levels since peat consists chiefly of decomposed and undecomposed organic
matter (Alexander 1971).
Higher organic loadings in wetlands, such as with the addition of waste-
water, will alter the prevailing DO regime. It will require the flora and
fauna of wetlands to adapt to larger fluctuations in DO, if they are not
already adapted. It will also result in greater decomposition rates and
greater oxygen consumption.
*Those species not adapted to lower DO or anoxic conditions will die or
emigrate.
154
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.2 pH
pH LEVELS INFLUENCE WETLANDS CHARACTERISTICS
The pH typically associated with wetlands is less than
7.0, indicating acidic conditions. This condition is
derived from leaching organic acids from wetland
vegetation. The pH significantly impacts the species
composition and water chemistry of wetlands systems.
The surface waters of wetlands are generally acidic (pH less than 7.0).
The low pH normally found in colored (humic) waters is derived from the acid
nature of organic compounds dissolved in the water, typically leached from
wetland vegetation. Dierburg and Brezonik (1980) proposed that rainfall
supported the acidic conditions in cypress domes, since the outside sources
of organic acids from runoff and stream flow are limited. Beck et al. (1974)
reported that organic acids were primarily responsible for the acidity in
riverine swamps of the southeastern United States.
The acidity of northern bog systems is greater in those communities domi-
nated by Sphagnum (Clymo 1967). Clymo suggested that Sphagnum acts as a
cation exchanger and is a major source of bog acidity. Sphagnum may also be
responsible for acidity in wetlands of the Southeast. Dierburg and Brezonik
(1980) suggested that other acidophilic plants such as Utricularia spp. (blad-
derwort) may also possess this capacity.
Daniel (1981) reported the pH in coastal pocosins of North Carolina
ranged from 2.2. to 6.6, averaging 4.4. Kuenzler et al. (1980) in studies of
riverine swamps of North Carolina noted average pH values ranging from 4.7 to
5.0 in a four-year study. Tributaries from a disturbed watershed tended to
elevate this pH. A pH range of 3.5 to 5.4 was reported in an undisturbed
cypress dome, with an average of 4.5 (Dierburg and Brezonik 1980). The min-
eral-rich groundwater beneath the dome registered pH of 6.0 and presumably
did not significantly influence the character of dome surface water.
A wetland system that is well-buffered tends to maintain a constant pH
throughout the year with little daily fluctuation. The buffering capacity of
water is an indication of its effectiveness in minimizing a pH change result-
ing from an addition of either acids or bases. Buffering capacity results
from the amount and type of dissolved material producing the acidity or
alkalinity. The source of this dissolved material may originate within or
outside the wetland. The surface water entering wetlands reflects the compo-
sition of the watershed. Dissolved substanaces may help to buffer the pH.
At pH 7, the bicarbonate-carbonate equilibrium is the major buffering system.
If groundwater is a major source of water for the wetland, its composition
(especially hard groundwater, high in carbonates or other salts) will raise
pH and buffering capacity. This is equally true of wetlands receiving
drainage in watersheds with a high amount of calcium and magnesium salts,
carbonate and bicarbonate ions, sulfate, chlorides or nitrates (hard waters).
155
-------
4.4.2 Continued
Wetland systems that are not well buffered are generally those with high
internal sources of acidity (plants, decomposition processes) and few outside
sources of alkalinity (hardwater runoff) such as bogs, bays, domes, pocosins,
and some marshes. Acidic rain throughfall helps maintain the acidic
conditions. In periods of intense photosynthesis by floating, emergent or
attached vegetation, the pH may be quite high (greater than 9.0); during
periods of high respiration and decomposition, the pH may be quite low (less
than 3.0). Respiration in sediments may depress pH locally due to the
production of organic acids.
The pH of water in wetlands is a factor to which all wetlands organisms
must adapt. Both nutrient release from sediments and the ionic form of
nutrients are pH dependent. Most organisms have a range of pH outside of
which they cannot effectively compete, grow or function. Some of these
ranges are narrow, others broad. The pH of most domestic wastewater is
approximately neutral and well buffered. The effects on the endemic pH of
wetlands depend on the relative volume of wastewater and the buffering
capacity inherent in the wetlands.
156
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.3 Metals
WETLANDS ACT AS NATURAL SINK FOR HEAVY METALS
Conclusive research about the fate of heavy metals 1n
wetlands is sparse. Several pathways of metal transport
and translocation have been identified. Metals tend to
accumulate in the sediments, but may be mobilized under
certain conditions. Because of the potential chronic,
toxic and food-chain effects, impacts of metals on wet-
lands should be carefully considered.
Heavy metals are of concern because of their potential adverse effects.
Opinions differ as to the definition of heavy metals from a toxicological
standpoint. The most common heavy metals include titanium (Ti), vanadium
(V), chromium (Cr), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic
(As), silver (Ag), cadmium (Cd), tin (Sn), mercury (Hg) and lead (Pb). The
form of heavy metals is important to the solubility and toxicity in the aqua-
tic environment (Figure 4.4.6). Heavy metals have been classified based oh
their solution chemistry into three classes: oxygen-seeking, nitrogen-sulfur
seeking and intermediate (Nieboer and Richardson 1980).
The aquatic-related fate of these metals has been included in a review of
this subject by Callahan et al. (1979). The health impacts, allowable limits
related to acute, subacute and chronic toxicity, synergistic or antagonistic
actions, teratogenicity, mutagenicity and carcinogenicity have been summar-
ized by Sittig (1980).
Heavy metals entering wetland ecosystems may experience three immediate
pathways of transport and translocation, (1) plant or animal uptake, (2) move-
ment to surface or groundwaters, and (3) immobilization into the soil matrix
(see Figure 4.4.5). Klien (1976) and Carriker (1977) studied the fate of
heavy metals in freshwater cypress domes, but the concentrations of metals in
the source (domestic effluent) was too low to determine the ultimate fate of
metals. Boyt et al. (1977) reported low concentrations of zinc, copper, and
lead in the effluent of the Wildwood, Florida sewage treatment plant and in
the receiving swamp. The concentrations of metals in the surface water and
sediment cores in a marsh receiving effluent since 1919 (Murdoch and Capo-
bianco 1979) were low and variable and no trends were detected.
Aquatic plants undoubtedly assimilate heavy metals from the water (Kadlec
and Kadlec 1979, Dinges 1978). The leaves of hyacinth culture receiving
treated sewage were found to contain high levels of Cr, Cu, Fe, Hg, Mn, Ni
and Zn. However, Ag, Cd and Pb concentrations were below detection limits
(Dinges 1978). Roots are also known to assimilate metals (Lee et al. 1976).
Heavy metals are easily adsorbed onto sediments trapped there by adsorption
to ion-exchange sites, incorporation into the lattice structure, or precipi-
tation as metal colloids. Carriker and Brezonik (1976) reported elevated
levels of metal associated with surficial sediments of cypress domes receiv-
ing secondary effluent. Metals are also complexed by organic compounds such
157
-------
4.4.3 Continued
as fulvic and humic acids found in wetlands (Boto and Patrick 1978) and may
reduce bioavailability and uptake by insects, plants and animals.
These processes of transformation for soluble metals are important since
secondary effluents tend to have a major proportion of metals in the
dissolved state (Chen et al. 1974).
Changes in pH and Eh influence the solubility of metals and determine
whether metals are retained or released by the sediments. For example, the
release of Al, Mn, Fe, Zn from the sediments was observed for a pH range of
5-6, but Cs, Hg, Se showed reduced solubility (Schindler 1980). Metals
loosely adsorbed to the surficial sediments have not been shown to migrate to
groundwaters, but may be mobilized to surface waters (Tuschall et al. 1981).
Boto and Patrick (1970) suggested that wetland systems can act as a high
capacity sink for heavy metals deposited in the sediments. They warn that
natural or man-made alteration of the system (lowering the water table,
dredging, etc.) can result in the release of metals trapped in anaerobic
sediments. Metals associated with sediments have a greater probability of
accumulating in the benthic or detrital based food chain than assimilated by
plants and entering another food chain.
The rate of metal accretion and the degree of burial in the sediments are
critical factors in determining the loadings which can be endured by wetlands
without damage. The wisdom in discharging high levels of bioavailable metals
in an ecosystem where they can be circulated and accumulated is certainly
questionable. While the natural attributes of wetlands may permit them to
act as a sink for metals, it is not a fail-safe or even consistent attribute.
Careful consideration should be given to disposal of these hazardous
compounds whenever they are allowed to enter the ecosystem.
158
-------
INSOLUBLE
SULFIDES
ORGANIC COMPLEXES
(Insoluble)
ORGANIC COMPLEXES
(Soluble)
INSOLUBLE OXIDES,
HYDROXIDES,
CARBONATES, AND
PHOSPHATES
O Moderately Soluble
D Highly Soluble
Figure 4.4.3. Relationship of heavy metal form and solubility in the aquatic
environment.
Source: Tchobanoglous 1980.
159
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.4 Nutrients
WETLANDS CYCLE AND TRANSFORM NUTRIENTS
Carbon, nitrogen, phosphorus and sulfur are the basic
building blocks of living organisms. They are considered
the major nutrients necessary for sustenance and growth.
Understanding the flow of nutrients into and out of
wetlands is essential to assessing wastewater recycling
through wetlands.
Wetlands ecosystems couple biotic and abiotic components of the environ-
ment. Nutrients and other dissolved constituents, heavy metals, and
suspended solids, move through wetlands in association with the hydrologic
regime and atmospheric diffusion. These constituents can be altered by
uptake, cycling, dilution and diffusion. Nitrogen, phosphorus, carbon and
sulfur are major elements which cycle through the incoming waters and
atmosphere into the water, plants and sediments. Net retention or release of
these constituents is site dependent. The interpretation of the effect of
wetlands on any material parameter requires an understanding of the hydrology
of that site and mass balance calculations.
Nutrient flow into and out of wetlands is of prime importance to under-
standing the structure and function of wetlands. The dynamic character of
wetland hydrology impacts the flow and rate of nutrient exchanges within
wetlands and surrounding ecosystems. The ability of wetlands to act as
nutrient traps depends on hydrologic regime, litter fall pattern, and the
rate of litter decay (van der Valk et al. 1978). Wetlands with predomi-
nantly organic substrates accumulate less N and P in the above ground
vegetation than those with predominantly organic substrates, yet organic
substrates seem to be capable of long term storage of N and P (Whigham and
Bayley 1978) by other means.
The dependence of downstream ecosystems (most notably estuaries) on the
quantity and quality of water leaving riverine wetlands is being investigated
in the Southeast (de la Cruz 1978). The buffering capacity of lacustrine
marshes toward moderating nutrient inflow and eutrophication in lakes has
been documented (Kadlec and Kadlec 1978). The impact of wetlands on nutrient
dynamics in the environment is one of the important natural characteristics
of wetlands.
Transformations of carbon, nitrogen, phosphorus and sulfur are influenced
by the prevailing oxygen conditions (Figure 4.4.4). The rate of nitrogen,
carbon and sulfur transformations are heavily modified by bacterial activity;
however, phosphorus cycling is less dependent on bacterial activity. Bac-
teria actively respond to temperature, pH, DO and other environmental vari-
ables. For example, at pH less than 5.0, microbes involved in denitrifi-
cation are severely inhibited.
160
-------
Cell material. H.S
N,0, N, CH-,; :- Aerobic Zone
Figure 4.4.4. Carbon, nitrogen and sulfur transformations in oxygen-poor
(anaerobic) environments.
Source: Cambell 1977.
161
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.4 Nutrients
4.4.4.1 Nitrogen
NITROGEN CYCLING IN WETLANDS IS AN IMPORTANT AND COMPLEX FUNCTION
Nitrogen Is an essential nutrient to vegetation and is
abundant in wetlands. It can be either stored or exported
depending on hydrology, chemical, and vegetational charac-
teristics.
The nitrogen cycle in wetlands is complex and pathways are variable
depending on site conditions (Figure 4.4.4.1-a). The major storages for
nitrogen in wetlands are also variable. In wetlands with larger drainage
patterns, generally more nitrogen will enter the wetlands (riverine marshes,
swamps, others). Nitrogen fixation mediated by epiphytes or rhizosphere
microflora (van der Valk 1979) may be a significant source of nitrogen for
other wetlands. Nitrogen may then be cycled within the wetland or leave the
wetland in two principal manners. Simple hydrologic export of both dissolved
and particulate forms of nitrogen is important in riverine and lacustrine
wetlands. This form of export is important to downstream ecosystems (Wharton
et al. 1980). The escape of gaseous nitrogen formed in the wetland (deni-
trification) to the atmosphere is the other principle means of nitrogen loss
to wetlands. Denitrification is an extremely important nitrogen sink in
those wetlands which do not have a significant means of hydrologically
exporting nitrogen (cypress domes, bay heads, bogs). Graetz et al. (1980)
found that denitrification rates of 14 Florida wetland soils were variable.
The Everglades soil removed an equivalent of 2,900 g ha-1 day-1 while only
600 g ha~l day~l was removed by Valkaria soil. These rates are indicative of
the great potential for denitirfication in wetlands soils. Organic matter
content and pH were the two variables used to explain variation of denitri-
fication rate in a model constructed to predict denitrification rates of
wetland soils.
Many wetlands are ideally suited for denitrification processes for
several reasons. Denitrification first requires that nitrogen forms (NH3+,
organic-N) be converted to nitrates (N03) in an aerobic environment (ammoni-
fication and nitrification in Figure 4.4.4.1-b). The anaerobic sediments in
wetlands with plentiful organic carbon is the prime site of actual
denitrification, the reduction of N03 to N2 (gaseous). The gaseous nitrogen
then escapes through the water column and is lost to the atmosphere.
Nitrogen is also conserved and recycled within the wetland ecosystem.
Dissolved nitrogen forms, especially ammonium (NH4+) and nitrates (NOs) are
taken up (assimilation) by plants and bacteria and stored in biomass for
varying lengths of time, then released to be either recycled again or
exported or lost to sediment. Algae and bacterial use of nitrogen represents
a short term storage unless trapped in sediments. Trees, shrubs and other
higher order forms of biomass often represent long-term and nearly permanent
nitrogen storage. This assimilation component of the nitrogen cycle is shown
in Figure 4.4.4.1-b.
162
-------
4.4.4.1 Continued
The sediments are also a storage for nitrogen in wetlands (Figure
4.4.4.1-a). For example, ammonia or nitrate nitrogen may be pumped out of
the sediments by roots of plants for nutrition or may remain locked in
organic matter (peat) until it is either released through peat degradation or
flushed out by hydrologic surges. Leaching of fresh litter releases large
amounts of nitrogen but older litter may act as a sink for nitrogen that is
never released. Natural wetlands which become dry, or drained wetlands, may
release large quantities of nitrogen. Ammonia can be lost to the atmosphere
by volatilization (Figure 4.4.4.1-b). The decomposition in anoxic sediments
is slow and nitrogen contained in organic matter may accumulate faster than
it is released, acting somewhat like a nitrogen trap (van de Valk et al.
1978). Upon drawdown of water, the sediments become aerobic and decompo-
sition is much more rapid, typically releasing large quantities of dissolved
nitrogen (Alexander 1971).
Figure 4.4.4.1-a provides a graphic display of nitrogen and phosphorus
cycling through the environment. Factors important in regulating the
exchange of these compounds between the various compartments of their cycles
are also illustrated in the figure.
163
-------
WATERSHED,
ATMOSPHERE,
GROUND WATER,
TRIBUTARY INPUT
WATERSHED,
ATMOSPHERE,
GROUND WATER,
TRIBUTARY OUTPUT
LAND USI
VEGETATION
CLIMATE
GEOMORPHOMCT*
PRECIPITATION
V VWTIK PLOW
INORGANIC
NITROGEN
PHOSPHORUS
DECOMPOSITION
ION EXCHANGE
RE SUSPENSION
NVTRKNT
N: P RATIOS
OXYGEN
WATER FLOW
LIGHT
TEMPERATURE
NUTRIENT
CONCENTRATIONS
pH
NUTRIENT
UPTAKE
SECRETION
RESPIRATION
f EXCRETION
ION EXCHANGE
ORGANIC
NITROGEN
PHOSPHORUS
BACTERIA
FUNGI
DCTRITIVORY
ORGANIC UPTAKE
EXCRETION
DEATH
r FEEDING
smrrRATE TYPI
PARTICLE SIZE
C:N
JWTERMOVEMCKT
»YOEN
IIOTIC INTERACTIONS
REPRODUCTIONS
GROWTH
'C:N:P
PARTICLE SIZE
OXYGEN REOOX
pH, ALKALINITY
SUBSTRATE TYPE
ORGANIC MATERIAL
.TEMPERATURE
NUTRIENT PUMPING ( rSEDIMENTATION
BIOTA
\>
^NUTRIENT LIMITATION*
OXYKN
TOXIC EFFECT OF
•LUC-MCINS
SHADING BY ALGAE (
MACROPHYTES
LIGHT. pH. TEMPCRATUKl
. none COMWTITION
\PREOATION
REPRODUCTION
OROWTH
Rf*U«*CN«ON
NUTMCNT PUHPING
I WATER FLOW
WIND, MIXING
STRATIFICATION
(OXYGEN)
8IOTIC STIRRING
BACTERIAL TRANSFORMATION
REOOX, TEMPERATURE
MORPHOMETRY
CHELATOR (FE, S)
V ROOTED MACROPHYTES
SEDIMENTS
Figure 4.4.4.1-a. Generalized nitrogen and phosphorus cycling in aquatic
environments.
Source: Farnworth et al. 1979.
164
-------
VOLATILIZATION
ORGANIC N
AMMONIFICATION ^
ASSIMILATION
•
NM^.M
nn^""!!
NITRIFICATION fc
4
ASSIMILATION
ki/\^™ kt
N03-N
DENITRIFICATION ^
FIXATION
2
Figure 4.4.4.1-b. Major components of the nitrogen cycle in aquatic
environments.
Source: Farnworth et al. 1979.
-------
4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.4 Nutrients
4.4.4.2 Phosphorus
PHOSPHORUS CONCENTRATIONS DEPENDENT ON VEGETATION AND SOILS
Like nitrogen, phosphorus Is an essential nutrient to
wetlands vegetation. Unlike nitrogen, the phosphorus
cycle Is not complicated by significant export to the
atmosphere. Certain vegetation are able to utilize
phosphorus more effectively than others.
The movement of phosphorus in wetlands closely parallels nitrogen
movements. A significant exception is that phosphorus cannot leave or enter
wetlands in a gaseous form as does nitrogen (see Section 4.4.4.1). Conse-
quently fewer pathways exist within the phosphorus cycle, which is further
simplified by having fewer ionic valance states. Phosphorus, like nitrogen,
is an essential element for plant growth and may limit productivity in some
instances (Brown 1981), and like nitrogen, the patterns of phosphorus input,
output and availability is dependent on local hydrologic regimes.
Phosphorus may enter wetlands as one of many forms of organic-P or
inorganic-P from either surface waters or rain and throughfall at varying
rates (see Table 4.4.4.2), depending on local conditions. In many wetlands,
groundwaters may contribute to total phosphorus inputs. Phosphorus in the
ionic form is easily leached from trees and leaves. Mitsch et al. (1979)
found more phosphorus contributed by throughfall than actual rainfall in a
floodplain forest. Phosphorus is converted from organic-P to inorganic-P in
the sediments or the surface waters of wetlands by hydrolysis.- Inorganic-P
may be present as ortho- or poly-phosphate. Sorption of organic-P to
sediments is an important pathway in some wetlands, although sorption by
sediments inhibits the rate of hydrolysis (Rodel et al. 1977).
Phosphorus is transported from wetlands via hydrologic export through
surface and groundwaters, or biological export. Ionic forms of phosphorus
have a high affinity to clays (Brown 1981). Exchange reactions with clays
underlying some wetlands will immobilize phosphorus and prevent it from
reaching groundwater (Odum et al. 1978).
Within wetlands, phosphorus in the ortho-phosphate form is a mobile ion
and is readily assimilated by plants and returned to the soil in litter fall.
Phosphorus may also be precipitated or sorbed onto organic matter in an
exchange reaction. New leaf litter leaches phosphorus rapidly, while older
litter may actually accumulate phosphorus (van der Valk et al. 1978).
In oxygen-rich surface waters, ortho-phosphate forms insoluble complexes
with certain ions, most notably iron, aluminum and calcium. Aluminum and
iron phosphate fractions predominate in an acidic environment (Nur and Bates
1979). The resulting precipitate removes phosphorus from the water column.
Phosphorus is released from the sediments back to the oxygenated water column
166
-------
4.4.4.2 Continued
when anaerobic conditions prevail (Stumm and Morgan 1970). Phosphorus may
also be released as a result of the activity of sulfate reduction (Mitchell
1974).
The dynamics of phosphorus in wetlands is similar to nitrogen in its
dependence on hydrologic regimes for essential inputs. The patterns of
availability, assimilation and export of phosphorus vary among wetlands. In
wetlands with naturally high phosphorus inputs (floodplain forests)
phosphorus is found to accumulate in the leaves (Brown 1981).
The pattern of phosphorus uptake and release is also dependent on the
vegetation. Typical marsh vegetation and epiphytes are capable of rapid
phosphorus uptake and generally do so more rapidly than trees and shrubs
(swamp vegetation). The assimilation rate varies highly among plant species,
location and season (Kadlec and Kadlec 1978). Many plants take up nitrogen
and phosphorus in excess of current needs, a well documented phenomenon in
emergent marsh plants (Wetzel 1975). These same plants release nutrients
back into the wetland, and depending on the labileness of the returned
substance may be permanently stored in peats like nitrogen, or exported in
hydrologic surges.
167
-------
Table 4.4.4.2 Inputs of Total Phosphorus to Four Types of Cypress
Ecosystems.
Study site
Scrub cypress
Large Dome
Sewage Dome
Floodplain forest
Rainfall
0.11
0.09
0.09
*
Inputs (gP
Surface
Runoff
*
0.12
13.901
*
m2 yr-1)
Overbank
Flooding
**
**
**
1620.0
Total
0.11
0.21
13.99
1620.0
*Not estimated.
**Does not occur in these ecosystems.
^Includes sewage effluent
Source: Brown 1981.
168
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.4 Nutrients
4.4.4.3 Carbon
CARBON HAS A CENTRAL ROLE IN THE BIOLOGICAL AND CHEMICAL
FUNCTIONING OF WETLANDS
Carbon flow in wetlands is biologically regulated by
photosynthesis and respiration. Hydrologic imports and
exports of carbon are significant only in riverine and
lacustrine wetlands. Carbon is stored in biomass and in
organic sediments. The pH regulates the inorganic carbon
forms in natural waters and is a selective pressure on
plants. Organic carbon exports have important linkages
with downstream ecosystems. Humic and fulvic acids are
primary components of dissolved organic carbon which
imparts the typical tea-coloring to many wetland waters.
Carbon has a central role in the chemistry of life in wetlands. Like
other macronutrients (N,P,K, etc), carbon is present in organic and inorganic
forms. The majority of carbon in freshwater systems is often present as
simple inorganic carbon, principally as products of carbonic acid equilibrium
(C02, H2C03, HC03-, C03=). A lesser amount occurs in organic carbon com-
pounds as either dissolved particulate, or detrital organic carbon.
A small fraction of the total carbon in freshwater occurs as living
biomass (Wetzel 1975). Dissolved inorganic carbon in freshwater is important
in both biological and chemical processes. From a chemical standpoint,
inorganic carbon forms the basis of the carbonate-bicarbonate buffering
system in most freshwaters. Aquatic plants and algae utilize dissolved
inorganic carbon during photosynthesis. Some aquatic plants utilize
bicarbonate (HCOs_) which predominates at neutral pH, others (mosses) can
only utilize free C02 which predominates at pH less than 5.0. Other plants
and algae are able to utilize both HC03- or C02 (Wetzel 1975). The forms of
carbon in the water acts as a selective pressure for some plants (Etherington
1975).
In research on a floodplain forest, the primary inputs of carbon were
from the net primary productivity process of trees (Kuenzler et al. 1980).
The second most important source of carbon was hydrologic inputs (inorganic
and organic). Minor sources of carbon inputs were from the shrub-understory,
and algae. In the spring, before trees and 'shrubs begin active photosyn-
thesis, algae temporarily dominate carbon inputs (Kuenzler et al. 1980).
Rainfall and groundwater sources of carbon were minor.
The export of carbon from swamp forest wetlands is primarily from respira-
tion (biological) and hydrologic pathways. In the swamp floor, litter decom-
position was the major respiratory pathway with carbon returned to the atmos-
phere (Kuenzler et al. 1980). Respiration in the water column and benthic
respiration were other significant biological pathways of carbon export.
Hydrologic export in dissolved and particulate carbon was the most signifi-
169
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4.4.4.3 Continued
cant physical export of carbon. Release of carbon by benthic respiration may
occur under aerobic or anaerobic conditions. Methane production during
benthic respiration is strongly associated with anaerobic conditions (see
Figure 4.4.4), but is usually only a minor carbon export.
The accumulation of carbon reserves in wetlands is commonly stored in
biomass and the peats. This soil organic matter is typically 50 percent
carbon by dry weight (Wetzel 1975). Although many marshes, bogs and swamps
accumulate peats, it is not as typical in riverine swamps and marshes because
the organic matter is either flushed out or lost during drydown when respir-
ation is more rapid. A significant carbon export from some wetlands occurs
by fire. This is typically not on an annual basis but represents an impor-
tant export of carbon in those wetlands which are maintained by fire (see
Section 4.2.2). Fire is capable of releasing many years of accumulated
organic matter, much like periodic floods carying away accumulated sediments
(Ewel and Mitsch 1978, Monk 1968).
The aforementioned carbon inputs and outputs are not all applicable to
each wetland type within Region IV, but vary among wetland types and with
local conditions. The importance of any one pathway may be amplified or
diminished in accordance with local conditions and seasonal pulses.
In those wetlands with significant hydrologic export (riverine, lacus-
trine, wetlands), particulate and dissolved aquatic carbon export has sig-
nificant ecological importance. Both dissolved and particulate carbon forms
exported from wetlands have important ecological downstream linkages to
riverine and estuarine productivity. The seasonal timing of this export is a
delicate ecological balance in estuaries (Whigham and Bayley 1978, Simpson et
al. 1978), and wetland integrity is critical to maintaining this balance.
Humic and fulvic acids are dissolved organic (carbon-based) acids which
give many wetland waters their characteristic tea color. Dierburg and
Brezonik (1980) found a significant correlation between total organic carbon
(TOC) and color. These carbon compounds are important to the water chemistry
of wetlands. They also impede light penetration and thus algal productivity
by reducing the photic zone in wetlands. Humic or fulvic acids, often asso-
ciated with metals such as Fe or Zn, may bind with orthophosphate ions.
Humic materials are known for their complexing properties, most notably heavy
metals. Humics are also resistant to microbial decomposition (Alexander
1977).
170
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.4 Nutrients
4.4.4.4 Sulfur
SULFUR AFFECTS CYCLING OF OTHER NUTRIENTS, PRODUCTIVITY,
AND METALS DISTRIBUTION
The abundance of $64= in oxygenated surface water rarely
makes sulfur a limiting nutrient for plant growth.
Reduced forms of sulfur produced by decomposition may
mobilize phosphorus and increase plant growth.
Sulfur-metallic interactions provide a sink for metals in
wetlands.
Sulfur is used in both chemical and biotic forms by all living things.
The amount of organic sulfur in the biota and detritis is small in comparison
to the inorganic sulfur compounds in natural waters. The distribution and
cycling of sulfur in wetlands revolves around the various chemical states and
biotic activities endemic to wetlands. Typical transformations and storages
in the sulfur cycle are illustrated in Figure 4.4.4.4.
The source of sulfur inputs to wetlands is through rainfall and dry
deposition. In many wetlands hydrologic sulfur inputs are important, similar
to that of other nutrients. Sulfate ($04=) is the predominant form of sulfur
in oxygenated surface waters, naturally ranging from 5 to 30 mg/1 (Wetzel
1975), depending on local geochemistry. Groundwater may be a source or sink
of sulfur according to hydrologic flows. Sulfur from groundwater sources are
likely to be contributed in a chemically reduced state (H2S), but usually a
minor percentage of the total sulfur inputs.
Sulfur is generally present in excess of the needs of plants. It is
rarely a direct limiting factor in plant productivity for aquatic plants
(Wetzel 1975). The most commonly assimilated form of sulfur is the sulfate
ion (S04=) which is used to build proteins. Some bacteria assimilate H2S and
oxidize this form of sulfur as an energy source in anaerobic environments.
During decomposition, sulfur is released as H2S. The H2S is rapidly
converted to 804= by any oxygen which is present, effectively acting as a
scavenger of available oxygen.
1
No significant amounts of H2S were reported in natural cypress dome
sediments due to the oxygenated state of these sediments (Dierburg and
Brezonik 1980). The odor of H2S has been detected in the domes when
sediments are disturbed (Dierburg and Brezonik 1980) indicating that H2S may
be present at localized sites. Elemental sulfur (S°) may also be found
deposited by bacteria under low 02 and Eh conditions. The presence of HS is
rare in wetlands unless they are alkaline.
Several bacterial groups are important in sulfur cycle transformations.
The genus Proteus contains a group of common bacteria which degrade the
proteins contained in organic matter. High numbers of Proteus release
significant amounts of ^S which results in a reduction of Eh and dissolved
oxygen. This alteration of the chemical environment mobilizes phosphorus
171
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4.4.4.4 Continued
from the sediments which contributes to phosphorus limited plant productiv-
ity. Two other bacteria groups are found in connection with the production
of H2S in wetlands. The groups Beggiatoa and Thiothrix oxidize H?S as an
energy source. They are also known to store elemental sulfur (S°) inter-
cellularly. They may be essential in protecting plant roots from the phyto-
toxic effects of S in anaerobic sediments.
Another aspect of the sulfur cycle is the formation of metal sul fides by
this general reaction:
H2S + metal (Me++) — »> MS.
There is a strong affinity between sul fide (H2S) and iron (Fe) and once
formed (FeS), they are extremely insoluble. The precipitation of FeS is a
common sulfur-cycle pathway in wetlands. The removal of sulfide also
increases the migration of other metals (zinc, copper, lead) to the sedi-
ments, forming precipitates more insoluble than FeS.
172
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GJ
ABSORPTION -
DESORPTION
CLAY
ATMOSPHERE
SOIL
AND
SEDIMENTS
PHOSPHOROUS
RELEASE
IRON
SULFIDES
Figure 4.4.4.4. Generalized sulfur cycling in the environment.
Source: Odum 1971.
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4.0 NATURAL WETLAND CHARACTERISTICS
4.4 Water Quality
4.4.5 Bacteria
BACTERIA ARE IMPORTANT IN NUTRIENT CYCLING,
DETRITUS FORMATION
Specialized groups of bacteria are Important in the
cycling of N, P, C, and S In wetlands. More generalized
groups are responsible for an equally Important task of
decomposition and detritus formation. The public health
aspects of natural wetlands require close attention.
The microbial flora of wetlands is quite diverse. Certain microorganisms
are restricted in function to key roles in regulating nutrient cycling.
Others are generalized organisms adapted to decompose endemic and introduced
organic materials in wetlands. Still other microorganisms endemic to
wetlands (arbovirus) are significant threats to humans as reservoirs of
debilitating disease (Davis 1978).
The regeneration of nutrients is one of the most essential functions of
microorganisms in wetlands (Mitchell 1974). In order for these organisms to
function properly and release nutrients bound up in organic matter, they
require specific environments with regard to pH, oxygen conditions, carbon
substrate and temperature (Mitchell 1974). The regeneration of nutrients
begins with proteolytic bacteria, fungi, or actinomycetes which decompose
organic matter into simpler molecules. Decomposition proceeds more rapidly
for most organic substances in aerobic conditions than in anaerobic
conditions. Anaerobic degradation of organic matter is not only slow by
comparision but often results in the production of organic acids and
incomplete degradation. The refractory portion of organic matter forms the
basis for peat formation. If exposed again to air, the organic matter will
continue to be degraded.
Once simpler molecules are produced by general decomposing bacteria,
specialized groups of bacteria are responsible for further breakdown of
organic matter. For example, organic acids are utilized by a specialized
group of bacteria to produce methane (see Figure 4.4.4). Certain Bacillus
and Pesudomonas groups are responsible for converting nitric acid to nitrogen
gas for atmospheric release. Important transitions of sulfur compounds are
mediated by bacteria (see Section 4.4.4.4.). Each species has highly
specific range of environmental variables (pH, 03, temp.) outside which it
will not function. When these ranges are exceeded, important cycles may be
interrupted. For example, Nitrobacter is inhibited at low temperatures and
high pH. It is responsible for converting nitrite to nitrate. If this
bacteria does not function, a buildup of nitrite may occur which is toxic to
fish and humans. Nutrient cycle imbalances occur when conditions for key
microorganisms are not present.
The fate of other bacteria including fecal coliforms and pathogens will
be discussed in Section 7.1.5, Public Health.
174
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
COMMON, THREATENED AND ENDANGERED WILDLIFE SPECIES USE
WETLANDS AT LEAST DURING SOME PART OF THEIR LIFE CYCLE
Wetlands provide abundant food, water and shelter needed
for the continued existence of many wildlife species.
Thus, in many instances, a positive correlation exists
between wildlife survival and the availability of wet-
lands. This provides a basis for establishing wildlife
and recreational values of wetlands. This is particularly
important with regard to species that are listed as
endangered or threatened by federal and state agencies. A
large group of these species depend on wetlands for
survival, but many of these species do not appear on appro-
priate lists and may not be protected by state or federal
laws or statutes.
Wetlands provide abundant food, water and shelter needed by a large
number of wildlife species. Thus, adequate tracts of wetland areas are
needed if many species are to remain extant. Other factors unrelated to the
wetland itself affect the level of importance a given wetland plays in the
continued existence of wildlife. Climatic variability and atypical
reproductive periods are examples of other factors affecting the density and
diversity of species inhabiting wetland areas.
Many southeastern wetlands provide the requisites of survival for a wide
variety of wildlife species. Included are cypress domes, marshes, pocosins
and bottomland hardwood wetlands. The density and diversity of species
present in these wetlands at any one time depends on the current needs of the
species, the present ecological status of the wetland and the population
status of the species where the wetland is located. This abundance of
wildlife includes but is not limited to game animals and fish, song birds,
raptors, owls, racoons, minks, turtles, salamanders and snakes. The wildlife
values of wetlands lie not only in the survival of these wildlife groups, but
as well to conservation and education groups and those who pursue hunting and
fishing activities.
Several species of wildlife listed as endangered or threatened under the
Endangered Species Act of 1973 are dependent on wetlands for nutritional
and/or reproductive requirements. Each state in Region IV also maintains a
list of endangered or threatened species endemic to the state. Included in
these lists are species that are wetland-dependent. State listed species of
the endangered or threatened status may or may not be protected by state laws
or statutes.
175
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.1 Value of Wetlands as Habitat for Wildlife
WETLANDS PROVIDE FOOD, WATER, ESCAPE COVER AND REPRODUCTIVE
REQUIREMENTS FOR MANY WILDLIFE SPECIES
The use of wetlands by wildlife is common. Wetlands are
generally associated with greater habitat diversity which,
in turn, leads to a greater number of species and
individuals of each species. Climatic variability and
wetland size are examples of factors unrelated to habitat
that may affect species density and diversity in wetland
ecosystems. Pocosins, cypress domes, marshes and bottom-
land hardwood wetlands provide food, shelter and
reproductive requirements for a wide variety of wildlife
species, and many species depend heavily on wetlands for
survival during some portion of their life cycles.
The ability of wetlands to serve wildlife needs for food, shelter and
water depends on a variety of interrelated factors. Wildlife needs differ
with season and reproductive cycles. Weather conditions, predation and
atypical reproduction cycles may cause changes in species abundance from year
to year that are not associated with the condition of the wetland.
Conversely, wetlands generally contain a large number of species (species
richness) and a large number of species individuals (species density) because
wetlands form the meeting point between two or more types of plant
communities.
This interface of ecological communities is called the edge effect; both
the number of species and the total biomass will be larger in the edge area
than in any comparable area contained wholly within one or the other commun-
ity type. The degree of edge determines in part the carrying capacity of an
area (the limitation of the number of any one species that can be maintain-
ed). Most wetlands compare favorably with the best managed moist terrestrial
systems, in terms of primary productivity (Odum 1971). Thus, the hetero-
geneity of ecosystem types in a wetland complex creates habitat diversity
including high species richness.
Other factors may play an important role in determining whether wildlife
species are abundant in wetlands. For instance, the size of a wetland and
vegetation type and structure are vital to the maintenance of wetland fauna.
Wetlands wildlife also change in response to climatic (and seasonal) influ-
ences. In many instances, the form of vegetation seems to be more important
to wildlife than taxonomic composition (Schitoskey and Linder 1978).
In marshes, several distinct plant zones are produced by changes in depth
of inundation. A naturally devegetated marsh that is dewatered produces a
subsequent germination phase. Shallow-marsh plants dominate during this
period and are succeeded, after inundation depth increases, by more water
tolerant species such as cattail. This phase of vegetation change is
associated with a dense habitat dominated by vigorous aquatic emergents.
176
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4.5.1 Continued
Thus, dewatering followed by reflooding produces excellent interspersion of
emergent cover and water, and species richness and species diversity is
enhanced (Weller 1981).
Pocosins provide food, water, escape cover and reproductive needs for
several species which once ranged widely in North Carolina but are now con-
fined only to pocosins. The black bear (Ursus americana). white tailed deer
(Odocoileus virginianus) and the pine barrens treefrog (Hytia andersoni) are
examples of species which depend on pocosins for suitable habitat because
other areas have been developed. Pocosins also serve as food support systems
for species endemic to other community types. The eastern diamondback rattle-
snake (Crotalus adamentius) is endemic to flatwood ecosystems but feeds on
rabbits that depend on pocosins for food and shelter (Wilbur 1981). Several
small game species, including the marsh rabbit (Sylvilagus palustris). exist
where pocosins and surrounding agricultural areas meet, but habitat loss has
been an overriding factor causing a decline in total numbers (Monschein
1981). Birds use pocosins as nesting sites and/or as a source of food. Bob-
white quail (Colinus virginianus) use pocosins as a source of food. Pocosins
provide nesting and roosting sites for the mourning dove (Zenaidura
macroura), and the woodcock (Philohela minor) uses pocosins for shelter
during the day. The information available on pocosins as habitat for fish is
scarce. Monschein (1981) lists several endemic species occurring in canals,
lakes and streams.
Natural cypress domes serve a very important role as refuges for wild-
life. These wetlands also aid in stabilizing animal communities and pro-
viding abundant edge through which many species find food, water and shelter.
The edges of cypress ponds are highly dynamic areas of animal activity.
Jetter and Harris (1976) studied the effect of sewage effluent on wildlife
species in Florida cypress domes and tabulated important species endemic to
dome areas. They noted higher frog densities, lower mosquito, fish and
crayfish densities, greater numbers of dipteran detritivores, fewer herons
and greater passerine birds in the dome receiving sewage than in the control
(groundwater) dome.
Bottomland hardwood wetlands are transitional zones between the aquatic
stream ecosystems and the upland ecosystem. These wetlands are used exten-
sively by a large variety of wildlife. Many riverine fish species use these
types of wetlands for feeding, spawning and nursery grounds. Regardless of
how briefly bottomland hardwood wetlands are flooded, they contribute signi-
ficantly to the viability of riverine fishes and invertebrates. Prolonged
inundation of vegetated zones increase the probability of survival of fishes
during early life stages (Clark and Benforado 1980). The use of bottomland
hardwood wetlands by bird and mammals will differ by species, season and
flooding regime. Wharton et al. (1980) describes the major wildlife species
found in bottomland hardwood ecosystems.
177
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Species
ALL STATES IN REGION IV HAVE ENDEMIC SPECIES OF WILDLIFE CLASSIFIED
AS ENDANGERED OR THREATENED WHICH DEPEND ON WETLANDS
FOR NUTRITIONAL AND REPRODUCTIVE NEEDS
The Federal Endangered Species Act of 1973 lists 15
species endemic to Region IV that depend on wetlands for
food, shelter, and reproductive needs during at least some
part of the species' life cycle. The act emphasizes the
need to preserve critical habitats on which endangered and
threatened species depend for their continued existence.
Every state in Region IV has a list of unique state
species of the endangered, threatened or special concern
status that includes wetland dependent species. These
species may or may not be protected by state laws or
statutes.
The U. S. Department of Interior lists under the Endangered Species Act
of 1973 67 threatened and endangered wildlife species endemic to Region IV.
These two classes of protected species are defined as follows:
Threatened species: any species which is likely to become an endangered
species within the foreseeable future throughout all or a significant portion
of its range.
Endangered species: any species which is in danger of extinction through-
out all or a significant portion of its range other than a species of the
class Insecta determined by the Secretary to constitute a pest whose protec-
tion under the provisions of this Act would present an overwhelming and over-
riding risk to man.
In addition to protecting threatened and endangered species of wildlife,
the Act emphasizes the need to preserve critical habitats on which endangered
species depend for their continued existence. Individual states are also
encouraged to establish guidelines which will complement the goals of the
Act.
Fifteen species included in the federal list of endangered and threatened
species endemic to Region IV are known to be wetland dependent. For the
purposes of this report, wetland-dependent species classified as threatened
or endangered are species which depend on wetland habitat for food, water,
shelter and/or reproductive needs at least during some portion of the
specie's life cycle. Many species use wetlands exclusively for nutritional
and reproductive requirements and shelter needs. Some species, however,
require wetlands during only short periods of their life cycle. Table 4.5.2
lists these species and their distribution within Region IV.
178
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4.5.2 Continued.
The appropriate environmental resource agency for each state in Region IV
maintains and updates a state list of endangered or threatened species. Most
state lists are amalgamations of endangered and threatened species included
in the federal list and endemic wildlife deemed endangered, threatened, or of
special concern by state officials. Several states in Region IV have not
enacted specific laws to accomplish protection of state listed endangered
species, but instead, have general protective provisions for wild birds and
animals. These provisions are deficient in terms of ultimate authority and
enforceability to accomplish adquate protection of these species.
179
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Table 4.5.2.
United Stated Department of Interior Fish and Wildlife Service
List of Wetland-dependent Endangered (E) and Threatened (T)
Species Endemic to Region IV.
Status Distribution
Mammals
Florida panther (Felis concolor coryi)
Birds
Mississippi sandhill crane (Grus canadensis
Bald eagle (Haliaeetus leucocephalus)
American peregrine falcon (Falco peFegrinus)
Bachman's warbler (Vermivora bachmanii)
Everglade kite (Rostrhamus sociabilis plumbeus)
Cap Sable seaside sparrow
(Ammospiza maritima mirabilis)
Dusky seaside sparrow
(Ammospiza maritima nigrescens)
Til
Brown pelican
!_gi[
Ivory billed woodpecker (Campephilus principalis)
•own pelican
(Pelecanus Occident all's carol inensis)
Amphibians and Reptiles
American alligator (Alligator mississippiensis)
American alligator ((Alligato'r mississippiensis)
Pine barrens treefrog (Hyla andersoni)
Fish
Bayou darter (Etheostoma rubrum)
Okaloosa darter (Etheostoma okaloosae)
AL, FL, GA, MS, SC, TN
E MS
E AL, FL, GA, KY, MS, NC, SC
E AL, FL, GA, KY, NC, SC, TN
E AL, FL, GA, KY, MS, NC, SC
E FL
E FL
E FL
E FL
E AL, FL, GA, MS, NC, SC
E AL, GA, MS, NC, SC
T1 FL, GA, SC
E FL
T MS
E FL
igator populations are threatened in Florida and coastal areas of Georgia
and South Carolina.
Source:
Adapted from the United States Fish and Wildlife Service List of
Threatened and Endangered Species of Fish and Wildlife (50 CFR
17.11)
180
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.1 Alabama
ALABAMA HAS 25 SPECIES LISTED AS THREATENED, ENDANGERED OR OF SPECIAL CONCERN
The Alabama Department of Conservation and Natural
Resources maintains and updates an unofficial list of
species considered to be in need of protection, but
Alabama has no official law or regulation that protects
these species. The unofficial list includes a variety of
wetland dependent mammals, birds, fish and reptiles and
amphibians. These species are classified as being
threatened, endangered or of special concern.
Alabama has no law or regulation that protects rare and endangered
species in the state. An unofficial list of endangered species does exist.
The list includes all species protected by federal laws and regulations and
species which the Alabama Department of Conservation and Natural Resources
(DCNR) has considered to be in need of protection. By using a uniform class-
ification scheme, DCNR lists endangered species as those in danger of extinc-
tion throughout all or a significant portion of their range in Alabama.
Threatened species are likely to become endangered. Species of special
concern must be continually monitored because imminent degrading factors,
their limited distribution or other physical or biological characteristics
may cause them to become threatened or endangered in the foreseeable future.
Table 4.5.2.1 lists all wetland dependent species classified as endan-
gered, threatened, or of special concern in Albama. Boschung (1976) dis-
cusses the methodologies used in the classification of species into one of
the three categories.
181
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Table 4.5.2.1. List of Wetland-Dependent Species in Alabama of
Endangered Status (E) Threatened Status (T) and
Special Concern Status (S).
Status
Mammals
Florida black bear (Ursus americanus floridanus) E
Florida panther (Felis concolor coryi'l E
Southeastern shrew (Sorex longirostis) S
Marsh rabbit (Sylvilagus palustris palustris) S
Bayou grey squirrel (Sciurus carolinensis fuliginosus) S
Meadow Jumping Mouse "(Zapus hudsonius americanus)S
Fish
Slackwater darter (Etheostoma boschungi) T
Broadstripe shiner (Notropis~euryzonus) S
Brindled madtom (Noturus miurus)S
B1 rds
Bald eagle (Haliaeetus leucocephalus) E
Osprey (Pandion haliaetus)E
Peregrine fa1con~{Fa1co peregrinus) E
Bachman's warbler (Vermi'yora bachmanii) E
Ivory-billed woodpecker (Campephilus principalis) E
Little blue heron (FloridiTcaerulea)' S
Wood stork (Mycteria americana)S
Swallow-tailed kite (Elanoides forficatus) S
Sandhill crane (Grus canadensis") S
Amphibians and Reptiles
Flatwoods salamander (Ambystoma cingulatum) E
American alligator (Alligator mississippiensis) T
Alabama red-bellied turtle (Pseudemys alabamensis) T
River frog (Rana heckscheri) S
Greater siren(Siren lacertina) S
Florida green water snake (Matrix cyclopion floridana) S
North Florida black swamp snake (Seminatrix pygaea pygaea) S
Source: Adapted from Boschung. 1976.
182
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.2 Florida
FLORIDA HAS 31 SPECIES OF WETLAND-DEPENDENT WILDLIFE CLASSIFIED AS
EITHER ENDANGERED, THREATENED OR OF SPECIAL CONCERN
The Florida Endangered and Threatened Species Act of 1977
recognizes species of endangered or threatened wildlife
including mammals, birds, fish, amphibians and reptiles.
The act applies to any member of the animal kingdom and
defines the terms endangered, threatened and special con-
cern. The Florida Game and Fresh Water Fish Commission
has published a list of animals classified under these
three categories. Included In the list are 31 wetland-de-
pendent species.
In 1977 the State of Florida enacted the Florida Endangered and Threat-
ened Species Act of 1977. The act applies to a list of species classified as
either endangered, threatened or of special concern. The Florida Game and
Fresh Water Fish Commission defines an endangered species as a resident of
the state during a substantial portion of its life cycle and which is in imme-
diate danger of extinction or extirpation from the state or which may attain
such a status within the immediate future unless it or its habitat are fully
protected in such a way as to enhance its survival potential. The commission
defines a threatened species as one which is acutely vulnerable to
environmental alteration and whose habitat is declining in area at a rapid
rate and as a consequence is destined to become an endangered species within
the foreseeable and predictable future. A species of special concern, as
defined by the commission, is one which warrants special protection because
it occurs disjunctly or continuously in Florida and has a unique and signifi-
cant vulnerability to habitat modification or environmental alteration which
may result in its becoming a threatened species.
Table 4.5.2.2 lists and designates the endangered, threatened and
special concern species in Florida. Pritchard (1978) discusses ranges and
habitat requirements and describes most of the species listed in the table.
183
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Table 4.5.2.2. List of Wetland-Dependent Species in Florida of
Endangered Status (E) Threatened Status (T) and
Special Concern Status (S)
Status
Mammals
Pallid beach mouse (Peromyscus polionptus decoloratus) E
Florida panther (Felis concolorcbryi)E
Choctawhatchee beach mouse (Peromyscus polionotus allopyhrys) T
Perdido Bay beach mouse (Peromyscus polionotus trisyllepsis) T
Florida black bear (Ursus americanus floridanus") T
Everglades mink (Mustela vison evergladensis)T
Fish
Okaloosa darter (Etheostoma okaloosae) E
Crystal darter (Ammocrypta asprella) T
Saltmarsh topminnow (Fundulus jenkTnsi) S
Birds
Wood stork (Mycteria americana) E
Everglade kite (RosTrhamus sociabilis) E
Peregrine fa1con~TFa1co peregrinus)E
Ivory-billed woodpecker (Campephilus principal's) E
Bachman's warbler (Vermivora bachmanni)E
Dusky seaside sparrow (Ammospiza maritima nigrescens) E
Cape Sable seaside sparrow (Ammospiza maritima mirabilis) E
Eastern brown pelican (Pelecanus occidental is carolinensis) T
Bald eagle (Haliaeetus leucocephalus)T
Audubon's caracara (Caracara cheriway auduboni) T
Florida sandhill crane (Grus canadensiT)T
Roseate tern (Sterna dougalliT)T
Little blue heron (Florida caerulea) S
Snowy egret (Egretta thula) S
Louisiana heron (Hydranassa tricolor) S
Amphibians and Reptiles
Pine barrens treefrog (Hyla andersoni) E
Florida brown snake (Storeria dekayi victa) T
American alligator (Alligator mississippiensis) S
•'•Classified as endangered on the federal list.
Source: Adapted from Pritchard. 1978.
184
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.3 Georgia
GEORGIA LISTS SIX ENDANGERED SPECIES AND ONE THREATENED
SPECIES THAT ARE WETLAND DEPENDENT
The Georgia Department of Natural Resources lists 23
unusual, rare, threatened or endangered species. Of
these, seven species use wetlands during some part of
their life cycles. Under the Georgia Endangered Wildlife
Act of 1973, only habitats on public lands are protected
to enhance the survival of these species. The Act does
not affect private property rights nor can it impede con-
struction of any nature. Georgia law has, however,
established a regulatory program and review process to
provide for the protection of certain identified species
and their habitat.
In 1973, Georgia passed the Endangered Wildlife Act to protect various
species existing in the state. Under this Act, the Georgia Department of
Natural Resources (DNR) was required to identify species considered endan-
gered, threatened, rare, or unusual. These classes are defined as follows:
Endangered Species: Any resident species which is in danger of
extinction throughout all or a significant portion of its range or one which
is designated as endangered under the provisions of the federal Endangered
Species Act of 1973.
Threatened Species: Any resident species which is likely to become an
endangered species within the foreseeable future throughout all or a signifi-
cant portion of its range or one that is designated as threatened under the
provisions of the federal Endangered Species Act of 1973.
Rare Species: Any resident species which, although not presently endan-
gered or threatened as previously defined, should be protected because of its
scarcity.
Unusual Species: Any resident species which exhibits special or unique
features and because of these features deserves consideration in its con-
tinued survival in the state.
Georgia's act provides that only habitats on public lands shall be pro-
tected (Smith 1978). The DNR has made a list of 23 species which are rare,
unusual, threatened or in danger of extinction. The list includes seven
species which depend on wetlands. All of these species are endangered with
the exception of the American alligator (Alligator mississippiensis). This
reptile is classified as endangered along the Georgia coastal plain and
threatened in other coastal regions. Odum et al. (1977) gives a complete
description of each species range and habitat requirements.
Table 4.5.2.3 lists these species and indicates their status.
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Table 4.5.2.3. List of Wetland-Dependent Species in Georgia of
Endangered Status (E) Threatened Status (T), Rare
Status (R) or Unusual Status (U)
Status
Mammals
Florida panther (Pelis concolor caryi) E
Fish
none
Bi rds
Ivory-billed woodpecker (Campephilus principal's) E
Peregrine falcon (Falco peregrinusj" E
Southern bald eagle (Ha'liaeetus leucocephalus leucocephalus) E
Brown pelican (Pelecanus occidental's carolinensis)T
Bachman's warbler (Vermivora bachmanif)E
Amphibians and Reptiles
American alligator (Alligator mississippiensis) E/Tl
^American alligator is an endangered species along the Georgia coastal
plain and a threatened species in coastal areas.
Source: Adapted from Odom et al. (eds). 1977.
186
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.4 Kentucky
KENTUCKY LISTS 14 RARE OR ENDANGERED SPECIES THAT ARE WETLAND DEPENDENT
Species designated as endangered by the Secretary of
Interior are considered an endangered species In Kentucky.
The state also has a list of rare, threatened, or
endangered species, many of which are affected by these
regulations. From the total list, 14 species are wetland
dependent; three are endangered, the rest are considered
rare.
Kentucky administrative regulations allow the state to comply with the
federal Endangered Species Act of 1973 and gives the jurisdiction for
enforcing these regulations to the Kentucky Department of Fish and Wildlife
Resources. The regulations pertain to the federal list of endangered and
threatened species listed in Table 4.6.1. Kentucky also maintains and
updates a state list of rare species which the Endangered Species Regulation
does not protect. These species are protected (except rats, mice and shrews)
by Kentucky statutes unless there is a regulation permitting them to be
taken. Fourteen endangered and rare wetland-dependent species are protected
by federal regulations or Kentucky statutes.
Table 4.5.2.4 lists endangered and rare species in Kentucky, and Parker
and Dixon (1980) describes their distribution, habitat and characteristics.
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Table 4.5.2.4. List of Wetland-Dependent Species in Kentucky of
the Endangered Status (E) Threatened Status (T), or
Rare Status (R)1.
Status
Mammals
Cougar (Felis concolor)
River otter (Lutra canadensis)
Black bear (Ursus americanus)"
Swamp rabbit (Sylvilagus aquaticus)
Fish
Mud darter (Etheostoma asprigene)
Birds
Bald eagle (Haliaeetus leucocephalus)
American peregrine falcon (Falco peregrinus)
Osprey (Pandion haliaetus)
Mississippi kite (Ictinia misisippiensis)
Sandhill crane (Grus canadensis)
Amphibians and Reptiles
Western lesser siren (Siren intermedia)
Western bird voiced treefrog (Hyla avTvoca avivoca)
Green treefrog (Hyla cinera cinerea)
Western mud snake (Farancia abacura reinwardti)
Green water snake (Natrix cyclopion cyclopionj
Broad-banded water snake (Natrix fasciata confluens)
Alligator snapping turtle (Macroclemys temminckT]
Slider (Chrysemys concinna hieroglypnicT)
E
R
R
R
E
E
R
R
R
R
R
R
R
R
R
R
R
iRare species are protected (except rats, mice and shrews) by Kentucky
statutes unless there is a regulation permitting them to be taken.
Source: Adapted from Parker and Dixon. 1980.
188
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.5 Mississippi
IN MISSISSIPPI, 14 ENDANGERED AND THREATENED WILDLIFE SPECIES
ARE WETLAND-DEPENDENT
The Mississippi Game and Fish Commission adopted a list of
endangered and threatened vertebrates In 1977. Fourteen
wetland-dependent species are included In this list.
The State of Mississippi passed the Nongame and Endangered Species
Conservation Act to manage and protect wildlife and fish included in the
United States List of Endangered Fish and Wildlife. The state act requires
the Mississippi Game and Fish Commission to maintain an official list of
endangered and threatened species. All species on the list are protected by
state laws regulated by the Commission. The Commission defines an endangered
species as one which is in danger of extinction throughout all or a
significant portion of its range. A threatened species is one which may
become an endangered species within the foreseeable future in all or a
significant portion of its range. The list includes 14 species which are
wetland dependent.
Table 4.5.2.5 lists these species and indicates whether they are
endangered or threatened.
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Table 4.5.2.5. List of Wetland-Dependent Species in Mississippi of
the Endangered Status (E) and Threatened Status (T).
Status
Mammals
Florida panther (Fells concolor coryi) E
Black bear (Ursus americanus) T
Fish
Bayou darter (Etheostoma rubrum) E
Crystal darter (Ammocrypta asprella) E
Birds
Mississippi sandhill crane (Grus canadensis pull a) E
Bald eagle (Haliaeetus leucocephalus)E
Peregrine falcon (Falco peregrinus]" E
Bachman's warbler (Vermiyora bachmanii) E
Ivory-billed woodpecker (Campephilus principal is) E
Amphibians and Reptiles
Rainbow snake (Farancia erytrogramma) E
American alligator (Alligator mississippiensis) E
Black-nobbed sawback turtle (Graptemys nignnoda) E
Ringed sawback turtle (Graptemys oculifera)T
Yellow-blotched sawback turtle (Graptemys flavimaculata) T
Source: Adapted from the Mississippi Department of Wildlife Conservation
Bureau of Fisheries and Wildlife, Public Notice No. 2156.
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.6 North Carolina
NORTH CAROLINA HAS EIGHT WETLAND-DEPENDENT SPECIES
CLASSIFIED AS ENDANGERED OR THREATENED
The North Carolina Wildlife Commission is responsible for
monitoring the effects of proposed projects on any
wildlife species that is listed as either endangered or
threatened by federal or state authorities. Seventeen
resident species of wildlife are designated as endangered,
and eight of these species are wetland dependent. These
eight wetland-dependent species are also listed as
endangered under the federal Endangered Species Act of
1973.
North Carolina has general statutes authorizing the protection of
endangered and threatened wildlife species. Public funds may not be spent in
a way that would jeopardize the continued existence of certain species. The
North Carolina Wildlife Resources Commission is responsible for monitoring
the effects of proposed projects on these species. A listing of 17
endangered and four threatened species has been compiled for North Carolina.
The terms threatened and endangered, as defined by the Endangered Species Act
of 1973, are used to determine the status of species existing in North
Carolina. Eight wetland-dependent species are found on the North Carolina
list. These species are also included on the federalist and protected by
federal laws.
Table 4.5.2.6 lists these species and indicates whether the species is
endangered or threatened. Parker and Dixon (1980) discuss the description,
distribution, habitat and characteristics of these species.
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Table 4.5.2.6. List of Wetland Dependent Species in North Carolina
of the Endangered Status (E) and Threatened Status (T)
Status
Mammals
Eastern cougar (Pelis concolor cougar) E
Fish None
Birds
American peregrine falcon (Falco peregrinus) t
Artie peregrine falcon (Falco peregrinus tundris) E
Bachman's warbler (Vermivora bachmanii) E
Bald eagle (Haliaee^s leucocephalus) E
Ivory-billed woodpecker (Campephilus principalis) E
Brown pelican (Pelecanus occidentaTTs) E
Amphibians and Reptiles
American alligator (Alligator mississippiensis) E
Source: Adapted from Parker and Dixon. 1980.
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.7 South Carolina
THIRTEEN WETLAND-DEPENDENT WILDLIFE SPECIES ARE CLASSIFIED AS
ENDANGERED OR THREATENED IN SOUTH CAROLINA
The South Carolina Nongame and Endangered Species
Conservation Act of 1976 lists 25 endangered or threatened
wildlife species. Thirteen species on this 11st inhabit
wetlands at least during some portion of their life cycle.
A variety of other state laws, Including the Heritage
Trust Program Act, provide wetland habitat protection for
threatened or endangered wildlife species.
The South Carolina Wildlife and Marine Resources Department manages and
protects certain threatened and endangered wildlife species residing in the
state. Under the South Carolina Nongame and Endangered Species Conservation
Act of 1976, 25 endangered and threatened species are afforded protection; of
these species, 13 are wetland dependent. The act states that it is unlawful
to take, posess, or sell any of these species, but taking and possession of
these animals may be permitted in limited circumstances (Smith 1978).
Wetland habitat for threatened or endangered species can be protected from
development or other disturbances either directly or indirectly by a variety
of state laws including the Coastal Zone Management Act and the Heritage
Trust Program Act.
Table 4.5.2.7 lists the 13 wetland dependent wildlife species. Parker
and Dixon (1980) characterize the habitat and distribution of these species.
193
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Table 4.5.2.7.
List of Wetland Dependent Species in South Carolina
of the Endangered Status (E) and Threatened Status (T).
Status
Mammals
Eastern cougar
Fish
None
(Pelis concolor cougar)
Birds
American peregrine falcon (Falco peregrinus)
Bachman's warbler (Vermivora bachmanii )
Eastern brown pelican (Pelecanus occidentalis carolinensis)
Golden eagle (Aquila chrysaetos)
Swallow-tailed kite (Elanoides~forficatus)
Wood stork (Mycteria americana)
Cooper's hawk (Acciipiter cooperii)
American ospreyTPandion haliaetus)
Amphibians and Reptiles
Pine barrens treefrog (Hyla andersoni )
American alligator (Alligator mississippiensis)
E
E
E
E
E
T
T
T
E
E
Source: Adapted from Parker and Dixon. 1980.
194
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4.0 NATURAL WETLAND CHARACTERISTICS
4.5 Wildlife
4.5.2 Threatened and Endangered Wildlife Species
4.5.2.8 Tennessee
THIRTEEN WETLAND-DEPENDENT WILDLIFE SPECIES ARE CLASSIFIED AS
ENDANGERED OR THREATENED IN TENNESSEE
A number of wildlife species in Tennessee have been
officially listed by the Tennessee Wildlife Resources
Agency as endangered or threatened. Thirteen species
that depend on wetland ecosystems for survival are
included in this list. The Tennessee Nongame and
Endangered or Threatened Wildlife Species Conservation Act
of 1974 requires the protection of these species. The
Tennessee Department of Conservation maintains a computer
bank concerning key habitats used by these species.
The Tennessee Wildlife Resources Agency (TWRA) and the Heritage Program
(THP) of the Tennessee Department of Conservation are most directly concerned
with the protection of rare species endemic to Tennessee. Through the
Tennessee Nongame and Endangered or Threatened Wildlife Species Conservation
Act of 1974, these agencies protect and classify wildlife species whose
existence is deemed to be endangered, threatened, or in need of management.
In general, the state uses the federal definitions of endangered and
threatened to classify rare species. In need of management and special
concern are terms assigned to those species which may not currently exist at
or near their optimum carrying capacity (Eagar and Hatcher 1980).
Fifty-seven species of wildlife are listed as either endangered or threatened
in Tennessee. The Tennessee Department of Conservation maintains a computer
bank concerning the location of key habitat areas for these species.
Thirteen wildlife species of the endangered or threatened status depend on
wetland ecosystems for survival. Eagar and Hatcher (1980) have surveyed the
status of these species to learn their distribution, population density,
ecological requirements, limiting factors and management potential.
Table 4.5.2.8 lists all wetland-dependent wildlife species classified as
endangered and threatened in Tennessee.
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Table 4.5.2.8.
List of Wetland Dependent Wildlife Species in Tennessee
of the Endangered Status (E) and Threatened Status (T)
Status
Mammals
Eastern cougar (Pelis concolor cougar) E
Florida panther (Pelis concolor coryi) E
River otter (Lutra canadensis) T
Fish
Slackwater darter (Etheostoma boschungi) T
Trispot darter (Etheostoma trisella) T
Birds
Bachman's warbler (Vermivora bachmanii) E
Peregrine falcon (Falco peregrinus)E
Bald eagle (Haliaeetus leucocephalus) E
Ivory-billed woodpecker (Campephilus principal is) E
Brown pelican (Pelecanus occidental is) E
Mississippi kite (Ictinia misisippiensis) E
Osprey (Pandion haliaetus) E
Marsh hawk (CiFcus cyaneus hudsonius) T
Black-crowned night heron (Nycticorax nycticorax) T
Amphibians and Reptiles
Western pigmy rattlesnake (Sistrurus miliarius sticckeri) T
Source: Adapted from Eagan and Hatcher. 1980.
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SECTION 5
INSTITUTIONAL CONSIDERATIONS
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5.0 INSTITUTIONAL CONSIDERATIONS
INSTITUTIONAL CONSIDERATIONS HAVE AN IMPORTANT BEARING ON IMPLEMENTATION
OF WETLAND DISCHARGES
Federal and state regulations determine the feasibility
and final form of wetland discharges; however, regulations
must be promulgated on a firm base of technical under-
standing. The question of considering wetlands for
treatment or disposal of wastewater effluent is one
example of an institutional issue which must be resolved
through technical and regulatory considerations in order
to facilitate implementation. Additional implementation
problems and institutional issues which must be addressed
concern wetlands ownership and proprietary rights,
wasteload allocations and effluent limitations, wetlands
definitions, and the need for evaluative criteria.
Wetlands, as part of the waters of the United States, are under the
jurisdiction of several federal agencies charged with natural resource
management and pollution control. In addition, wetlands are almost always
considered waters of the state under individual state laws and are further
regulated under Section 404 (dredge or fill permits) or Section 402 (NPDES
permits) of the Federal Water Pollution Control Act (PL 92-500, as amended).
Wetlands have also been the subject of official policy statements and
executive orders concerning resource protection and federal funding.
With the emphasis that has been placed on resource protection, it is
understandable that wetlands use, particularly for treated wastewater
discharges, has not been pursued in a systematic manner. Potential policy
conflicts exist between federal agencies, between state and federal agencies,
and among various states. Existing state policies concerning wetland
discharges vary between all eight EPA Region IV states and may result in
regulatory inequities at the state and regional levels.
While certain policy differences between individual states are necessary
considering the variability of wetland types, certain questions must be
addressed at the regional or even national levels. The issue concerning
wetlands for treatment or disposal has a direct bearing on many other
institutional considerations such as wastewater treatment levels, effluent
limitations, ownership and proprietary rights, and potential federal funding.
Although existing regulations preclude consideration of wetlands for
treatment, the technical literature illustrates the treatment capacity of
certain wetlands. Clearly, the issue of treatment or disposal remains open
to f^er .debate and clarification. Other institutional issues such as
wetland definitions and the need for evaluative criteria also highlight the
need for state initiatives under the direction of regional policies.
Institutional considerations are discussed further in the following
subsections as well as in Section 9.2, Summary of Critical Institutional Con-
siderations.
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5.0 Continued
Issues of Interest
• Which federal agencies are involved in wetlands protection and
regulation?
• How do federal policies and regulations affect the use of wetlands for
wastewater effluent disposal?
• What are the state policies and regulations concerning wetland discharges
and how do they differ among the eight EPA Region IV states?
• How are wasteload allocations currently set for wetland discharges?
t What are the arguments concerning the use of wetlands for wastewater
treatment vs. wastewater disposal?
• What are the current implementation problems facing potential wetland
dischargers?
198
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5.0 INSTITUTIONAL CONSIDERATIONS
5.1 Federal Policies and Regulations
EPA, COE AND FWS ARE THE PRIMARY FEDERAL AGENCIES WITH WETLANDS
REGULATORY JURISDICTION
The U.S. Environmental Protection Agency (EPA) has
promulgated regulations pertaining to wetlands pursuant to
Section 402 and 404 of the Federal Water Pollution Control
Act. The U.S. Army Corps of Engineers (COE) has
jurisdiction over dredge and fill activities in wetlands
(Section 404 Permit Program). The U.S. Fish and Wildlife
Service (FWS) has only advisory functions relating to the
Fish and Wildlife Coordination Act.
Federal involvement in the protection and regulation of wetlands stems
from the definition of "waters of the United States" (40 CFR 122.3) and the
Federal Water Pollution Control Act (PL 92-500, as amended). Section 402 of
the Act established the National Pollutant Discharge Elimination System
(NPDES) to provide a permitting system for all point source pollution dis-
charges into waters of the U.S. Section 404 of the Act established a permit
program, administered jointly by EPA, COE and approved states, to regulate
the discharge of dredge or fill material into waters of the U.S. The FWS has
review authority over all Section 402 and Section 404 Permits in accordance
with the Fish and Wildlife Coordination Act.
In addition to the above mentioned federal laws and regulations, several
policy statements have been issued pertaining specifically to wetlands. In
1973, EPA issued a Statement of Policy on Protection of the Nation's
Wetlands, which elaborated the agency's position concerning wastewater
disposal to wetlands. However, implementation of this policy through rules
and regulations has not taken place. In 1977, President Jimmy Carter issued
Executive Orders 11988, Floodplain Management, and 11990, Protection of
Wetlands. Both executive orders limited federal activities in floodplains
and wetlands and further emphasized the need for interagency cooperation
concerning the protection of these sensitive areas.
The following sections detail the involvement of the EPA, COE and the
FWS in the protection of wetlands, with special emphasis on the disposal of
treated wastewater to wetlands.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.1 Federal Policies and Regulations
5.1.1 U.S. Environmental Protection Agency
EPA REGION IV HAS NOT INSTITUTED AN OFFICIAL POLICY CONCERNING
THE DISPOSAL OF TREATED WASTEWATER TO WETLANDS
Discharges of treated domestic wastewater to wetlands are
regulated under Section 402 of the Federal Water Pollution
Control Act. In order to comply with the Act, municipal
dischargers must achieve at least secondary treatment;
however, certain aquaculture systems may be specially
permitted. The EPA issued an official Statement of Policy
on Protection of Nation's Wetlands on March 20, 1973 (38
FR 10834).
Based on the definition of "waters of the United States" (40 CFR 122.3),
discharges of treated wastewater to wetlands are regulated under Section 402
of the Federal Water Pollution Control Act (PL 92-500, as amended). Section
402 of the Act established the National Pollutant Discharge Elimination
System (NPDES) for permitting all point source pollutant discharges. All
potential dischargers must apply for and obtain an NPDES Permit before
discharging to wetlands. Further, in accordance with the Act, all municipal
dischargers were to achieve secondary treatment by July 1, 1977, unless the
water quality showed that stricter controls were needed. Proposed amendments
to the water quality standards regulations may have a distinct bearing on
water quality standards and criteria for wetlands. These proposed amendments
are further discussed in Section 5.1.4.
Based on Section 318 of the Act, aquaculture systems may be specially
approved and permitted under the NPDES Permit Program. The EPA Administrator
is authorized to promulgate regulations establishing procedures and guide-
lines appropriate to the "discharge of a specific pollutant or pollutants^
under controlled conditions associated with an approved aquaculture project"
(Section 318(a), FWPCA). Each state is also authorized to administer its own
aquaculture permit program upon approval of the program by the EPA Admin-
istrator. "Aquaculture project" is defined as a "managed water area which
uses discharges of pollutants into that designated area for the maintenance
or production of harvestable freshwater, estuarine, or marine plants or
animals" (40 CFR 122.56). Additional regulations or requirements pertaining
to aquaculture projects have not been promulgated.
On March 20, 1973, EPA Issued an official Statement of Policy on Protec-
tion of Nation's Wetlands (38 FR 10834). The explicit purpose of the policy
statement was to "establish EPA policy to preserve the wetland ecosystems and
to protect them from destruction through wastewater or nonpoint source dis-
charges and their treatment or control..." Minimizing alterations in the
quantity or quality of the natural wetlands flow was also a stated policy of
EPA. It was further stated that "it should be the policy of this Agency not
to grant federal funds for the construction of municipal wastewater treatment
facilities or other waste-treatment-associated opportunities which may inter-
face with the existing wetland ecosystem..." Specific requirements or review
procedures were not implemented in conjunction with this policy statement.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.1 Federal Policies and Regulations
5.1.2 U.S. Army Corps of Engineers
COE RESPONSIBILITIES RELATE PRIMARILY TO DREDGE AND FILL ACTIVITIES
COE responsibilities concerning the use of wetlands are
derived primarily froa Section 404 of the Federal Water
Pollution Control Act. Permits must be issued by the COE
before any dredge or fill activities can take place in
waters of the United States, including wetlands. A
nationwide general permit has been authorized for all
utility line crossings, including sewers and sewage
outfalls.
The U.S. Army Corps of Engineers (COE) is not directly involved in the
permitting of wetlands for wastewater disposal. Jurisdiction in wetlands is
derived from Section 404 of the Federal Water Pollution Control Act (PL
92-500, as amended) and the definition of waters of the United States (40 CFR
122.3). Section 404 of the Act establishes a permit program, administered by
the Secretary of the Army, to regulate the discharge of dredge or fill
material into waters of the United States.
In the past, the COE restricted its regulatory authority concerning the
discharge of dredge or fill material to mean high water levels and below.
However, in 1975 the COE was ordered by a U.S. Court to expand its jurisdic-
tion to all waters of the United States, including the primary tributaries of
navigable waters, adjacent wetlands, and lakes. Section 404 Permits are not
generally required for discharges beyond the "headwaters" of a river or
stream unless the interests of water quality require assertion of COE juris-
diction. "Headwaters" is defined as "the point on the stream above which the
flow is normally less than five cubic feet per second" (Federal Register,
7/19/77, Part II, p. 37124).
COE review and a Section 404 Permit may be required in conjunction with
the construction of sewage treatment facilities in wetlands, if dredge or
fill activities are part of the general construction. However, a specific
permit for pipeline or outfall construction may not be required. A nation-
wide permit has been authorized for all "dredge and fill material placed as
backfill or bedding for utility line crossings provided there is no change in
preconstruction bottom contours... A "utility line" is defined as any pipe
or pipeline for the transportation of any gaseous, liquid, liquifiable or
slurry substance for any purpose ..." (33 CFR 323.4). Additional information
concerning the COE Section 404 Permit program is contained in 33 CFR
-323-Permits for Discharges of Dredged or Fill Material into Waters of the
United States. Additional regulations pertaining to the discharge of dredge
or fill material have been promulgated by the EPA (40 CFR 230).
The COE does not have an official policy concerning the use of wetlands
tor wastewater disposal.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.1 Federal Policies and Regulations
5.1.3 U.S. Fish and Wildlife Service
FWS RESPONSIBILITIES ARE PURELY ADVISORY
FWS responsibilities concerning the use of wetlands are
primarily derived from the Fish and Wildlife Coordination
Act. Although the FWS is authorized to review all NPDES
Permits and wastewater facilities funding by EPA, most
review activities in relation to wetlands are focused on
the Section 404 Dredge or Fill Permits issued by the COE.
The Fish and Wildlife Coordination Act (PL 85-624 as amended by PL
89-72) is the major impetus behind the involvement of the U.S. Fish and
Wildlife Service (FWS) in wastewater management planning. According to this
law, any federal agency involved with a project to impound, divert, control
or modify the waters of any stream or other body of water must consult with
the FWS. This provision applies to the issuance of NPDES Permits and Section
404 Dredge or Fill Permits. Recommendations of the FWS should be made an
integral part of any report prepared or submitted by any federal agency
responsible for engineering surveys and construction of water resources
projects. In this review capacity, the comments and findings of the FWS are
only advisory and have no legal bearing on the approval or denial of any
federal permit or authorization.
In addition to the above review responsibilities, the FWS is authorized
under the Act to make appropriate investigations as deemed necessary to deter-
mine the effects of domestic sewage on wildlife and to make reports to Con-
gress concerning the results of these investigations. These investigations
should include a determination of appropriate water quality standards, the
study of pollution abatement and prevention, and the collection and dis-
tribution of appropriate data.
Although the FWS is authorized to review all NPDES Permits issued by
EPA, most review responsibilities of the FWS are focused on the Section 404
Dredge or Fill Permits issued by the COE (Brown 1982). Dredge or fill acti-
vities are generally considered by the FWS to be more damaging to wetlands;
however, the agency has expressed concern about wetland discharges. These
concerns are centered on alterations to wildlife habitat such as degradation
of water quality, accelerated eutrophication and vegetational changes. The
FWS does not have an official policy on the use of wetlands for wastewater
disposal but does have an official policy concerning the mitigation of the
loss of fish, wildlife and their habitat from land and water developments.
Based on this Mitigation Policy, the FWS response to a proposed wetland
discharge would depend upon the fish and wildlife resource values involved,
potential impacts to those resources, mitigation opportunities, and the
availability of feasible, less damaging alternatives (Huber 1982).
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5.0 INSTITUTIONAL CONSIDERATIONS
5.1 Federal Policies and Regulations
5.1.4 Proposed Amendments to the Water Quality Standards Regulation
PROPOSED AMENDMENTS MAY AFFECT WATER QUALITY CRITERIA FOR WETLANDS
Fundamental changes have been proposed to the water
quality standards regulations established under the Clean
Water Act. These changes will increase the states'
flexibility to review and revise water quality standards
on priority water bodies or segments rather than reviewing
all standards statewide every three years. States will
also be allowed to establish site-specific criteria and
remove or modify designated use classifications based on
analyses of the attainability of the uses and on benefit-
cost assessments.
Water quality standards are the foundation of the nation's water quality
management program and are used to define the water quality goals of a
particular water body. Specific uses are designated for a water body and
criteria are established to protect or achieve those uses. Criteria are
numerical or narrative descriptions of water quality parameters or pollutants
that must be maintained if the designated uses are to be met. It has been
argued that some existing water quality standards are unrealistic stemming
from the designation of overly-ambitious uses and the inflexibility of
recommended water quality criteria. Amendments to the regulations have been
proposed based on the premise of use attainability and the experience gained
from administering the program over the past several years. Proposed changes
to the water quality standards regulations concern the following:
- Focusing on priority water bodies rather than reviewing all standards
every three years.
- Determining the attainability of uses by characterizing present uses,
analyzing environmental and physical factors impacting the attainment of
a use, and assessing the benefits and costs of attaining a use.
- Promoting changes to (adding, removing or modifying) designated uses,
where reasonable.
- Developing site-specific criteria.
- Clarifying the antidegradation policy.
Provisions concerning use attainability, site-specific criteria, and varying
levels of aquatic protection may have the greatest bearing on water quality
standards for wetlands.
Use Attainability
In the past, water quality standards were often set to provide for the
protection and propagation of fish, shellfish and wildlife, and recreation,
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5.1.4 Continued
often without adequate analysis as to whether these uses were attainable.
Agricultural and industrial uses and navigation, which may have been more
appropriate uses, were usually rejected as not meeting the requirements of
the Clean Water Act. As a result, standards reflecting unreasonable stream
uses were sometimes adopted which either forced overly stringent and costly
treatment controls or were simply ignored in the implementation of water
pollution control programs (EPA Proposed Rule, 40 CFR Part 131).
The proposed amendments to the water quality standards regulations will
allow states to change use designations when legitimate factors effectively
prevent a use from being met. Use attainability analyses and benefit-cost
assessments will be used to determine the reasonableness of existing use
designations and justify proposed changes in the designations.
In the case of wetlands, discussions with state officials have indicated
that most wetlands are classified for fish and wildlife use. However, in
some instances, wetlands associated with other water bodies may carry the use
designation of the other water body, along with the corresponding water
quality criteria. This situation may have resulted in the application of
inappropriate or unreasonable water quality criteria to the wetland. The
proposed amendments provide a mechanism for. modifying use designations and
corresponding criteria where the current designations are found to be
unreasonable.
Site-Specific Criteria
Under Section 304(a)(l) of the Clean Water Act, EPA has developed
guidelines for surface water criteria. In the past, EPA operated under the
policy of presumptive applicability, requiring states to adopt a criterion
for a particular water quality parameter at least as stringent as the
304(a)(l) criteria recommendation unless the state was able to justify a less
stringent criterion. No guidance was provided to assist states in modifying
criteria based on site-specific local conditions and few modifications were
in fact accepted. Since the Section 304(a)(l) criteria are not rules and
have no direct regulatory impact, EPA rescinded the policy of presumptive
applicability on November 28, 1980 (45 FR 79320). (EPA Proposed Rule, 40 CFR
Part 131).
The proposed amendments to the water quality standards regulations will
encourage states to develop site-specific criteria reflecting local condi-
tions such as high natural background levels of certain pollutants and differ-
ences in temperature, hardness, and other parameters. In certain instances
designated uses may be met even though specific criteria are exceeded, and
the proposed regulations will allow these criteria to be modified following
EPA review and approval.
Site-specific criteria are most applicable to wetlands, where background
conditions usually differ significantly from other water bodies. Again, the
application of site-specific criteria will provide for greater flexibility in
regulating wetland water quality and may provide for greater use of wetlands
for wastewater management.
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5.1.4 Continued
Levels of Aquatic Protection
Level of protection refers to the impact on propagation, growth, survival
and diversity of species relative to various water quality criteria levels in
a water body. Levels of aquatic protection are also dependant on the type of
fisheries present and the existing habitat values. While the existing
regulations do not provide explicit references to define levels of protection
within the aquatic protection use category, the proposed amendments will
provide states the opportunity to define sub-categories of aquatic protection
uses (for example, warm water and wild water fisheries, fish survival, fish
passage, put-and-take fisheries, etc.)
The flexibility to assign varying criteria based on subcategories of
aquatic protection will increase the states flexibility in regulating
wetlands. Levels of aquatic protection for wetlands designated for fish and
wildlife use may vary according to the specific type of wetland and the
naturally occurring fish and wildlife community. This increased regulatory
flexibility may provide greater opportunities for wetlands use.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2 State Policies and Regulations
WETLAND DISCHARGE POLICIES AND REGULATIONS VARY
BY STATE THROUGHOUT REGION IV
Only Florida and South Carolina have explicit wetland
discharge policies; however, all states recognize the
inherent variability of natural water quality and provide
for exceptions to certain water quality criteria. Most
states use technological guidelines and qualitative
analyses when determining effluent limitations for dis-
charges into aquatic systems that cannot be modelled.
Definition
The definition of wetlands has an important bearing on how wetlands are
delineated and regulated at the state level. All eight states in EPA Region
IV recognize wetlands as waters of the state for the purpose of controlling
water quality and permitting wastewater discharges. However, variations in
the extent to which "waters of the state" is defined could have an important
impact on jurisdictional limits.
Florida is the only state which precisely defines the landward extent of
the waters of the state through the use of detailed species lists. All other
states maintain a broad definition subject to further clarification and
debate. Most states also deliberately limit the state's jurisdiction over
certain waters. With the exceptions of Kentucky, North Carolina and South
Carolina, Region IV states exempt from state regulations those waters wholly
confined and retained on the property of an individual owner or corporation.
No state limits the definition of "waters of the state" based on size or use.
Additional definition and delineation of wetlands is often done by the
individual states for the purpose of issuing Sections 404 Dredge or Fill
Permits or administering state fish and wildlife programs. Only North
Carolina and South Carolina define "swamp waters" for the purpose of estab-
lishing water quality criteria and permitting wastewater discharges.
Wetland Policies
State policies concerning wastewater disposal to wetlands vary and can be
either explicit or implicit. Only Florida and South Carolina have explicit
state policies concerning the conditions under which wetland discharges can
be permitted. All other states in EPA Region IV vary in the degree to which
they recognize wetlands as distinct systems and accommodate alternative water
quality criteria.
All state water quality regulations and criteria recognize the inherent
variations in natural water quality; however, Alabama and Georgia are the
only states which do not explicitly provide for exceptions to the water
quality criteria when the natural conditions are below the adopted standards.
Exceptions to water quality criteria have, however, been granted in both
Alabama and Georgia. North Carolina and South Carolina are the only states
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5.2 Continued
which have defined "swamp waters" in terms of water quality. Most often,
dissolved oxygen and pH are the parameters which are recognized as needing
variable criteria. No state explicitly permits discharges as a component of
the treatment process; wetlands discharge is only viewed as a disposal method
for treated effluent. Only Florida explicitly recognizes the potential
treatment capabilities of wetland systems.
Wasteload Allocations/Effluent Limitations
Each state has its own method of determining wasteload allocations and
effluent limitations for wetland discharges. Kentucky, North Carolina and
Tennessee are the only states that modify their standard stream models in
order to set permit limitations for discharges to wetlands; additional states
use water quality modeling for a wetland system as long as a distinct channel
can be defined. Most states simply use secondary treatment as a basis and
perform site-specific baseline studies to determine additional treatment
requirements and water quality criteria. EPA technical guidelines are often
used as the basis for treatment requirements when the aquatic system cannot
be modeled.
Monitoring Requirements
All state water quality regulations allow the establishment of monitoring
requirements on a site-specific basis. Most typical effluent monitoring
requirements include flow, BOD, dissolved oxygen, pH and total suspended
solids. Again, only Florida has explicit monitoring requirements outlined
for wetland discharges. In Florida, control system monitoring is required
for experimental wetlands.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.1 Alabama
ALABAMA REQUIREMENTS FOR WETLAND DISCHARGES DO NOT DIFFER
FROM OTHER WASTEWATER DISCHARGES
The Alabama Water Improvement Commission (AWIC) does not
distinguish wetlands from other waters of the state for
the purpose of permitting wastewater discharges. Permit
limits are based on technology guidelines and water use
and flow characteristics for the receiving waters.
Alabama was authorized to administer its NPDES permit
program in 1979.
Definition
Wetlands in Alabama are considered waters of the state, which are broadly
defined as "all waters of any river, stream, watercourse, pond, lake, coas-
tal, ground or surface water, wholly or partially within the state" (CA
22-22-1). Exceptions are made for waters totally confined or retained com-
pletely upon the property of a single individual. The AWIC further defines
and delineates wetlands using the Corps of Engineers definition (see Section
2.2.2). Other state agencies, specifically the Department of Conservation
and Natural Resources and the Coastal Area Board, may have different
definitions of wetlands which are better suited to their regulatory
responsibilities.
Wetlands Policy
The State of Alabama does not distinguish wetlands from other waters of
the state for the purpose of permitting wastewater disposal. Alabama regula-
tions recognize that natural waters may have characteristics outside of the
limits established by state water quality criteria; however, provisions are
not available to provide exceptions to specific water quality criteria. At a
minimum, secondary treatment is required for all wastewater discharges.
Wasteload Allocations/Effluent Limitations
Specific procedures and guidelines have not been developed for establish-
ing wasteload allocations and effluent limitations for wetland discharges.
Generally, permit limits for industrial discharges are developed from EPA
Best Available Technology/Best Conventional Pollutant Control Technology
(BAT/BCT)guidelines. In the absence of EPA guidelines, best engineering
judgement is used. Secondary treatment provides the initial basis for muni-
cipal discharge permit limits. In all cases, an analysis of water use and
flow characteristics for the receiving water shall be used for determining
the degree of treatment required.
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5.2.1 Continued
Monitoring Requirements
Specific monitoring requirements have not been established for wetland
discharges. The AWIC is responsible for determining the monitoring
requirements for each discharge, and the monitoring requirements may vary
according to the specific conditions and needs associated with each dis-
charge. Most discharges, at a minimum, monitor flow, BOD, total suspended
solids, ammonia-nitrogen and dissolved oxygen. Additional requirements may
be imposed on industrial discharges depending on the constituents of the
effluent.
\
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.2 Florida
WETLANDS DISCHARGES ARE PERMITTED WITH MODIFIED CRITERIA
Specific sections of the Florida Water Quality Standards
and the Permit Requirements provide for site-specific
water quality criteria and exemptions for experimental use
of wetlands. Additional requirements concerning hydraulic
loading and nitrogen and phosphorus removal may also be
applied to wetland discharges. Criteria are established
based on baseline studies without water quality modelling.
Florida has not been granted full authority to administer
the NPDES permit program.
The State of Florida has recognized the specific nature and potential
importance of wastewater disposal to wetlands. As a result, specific
exemptions and modifications can be made to the state water quality criteria
in order to permit wetland discharges, taking into consideration the
site-specific water quality and the nature of wetland systems.
Definition
Under state law, most wetlands are considered waters of the state and,
therefore, are under the jurisdiction of the Florida Department of Environ-
mental Regulation (FDER). Chapter 17-4 FAC Section 17-4.02 (17) defines
"landward extent of waters of the state" as that portion of a surface water
body indicated by the presence of one or a combination of the following as
the dominant species: (species list divided between submerged marine species
and submerged freshwater species) or that portion of a surface water body up
to the waterward first fifty (50) feet or the waterward quarter (1/4) of the
entire area, whichever is greater, where one or a combination of the
following are the dominant species: (species list divided between tradi-
tional freshwater species). Wetlands isolated from other bodies of waters
may not be considered waters of the state. This area of jurisdiction is not
explicit, and jurisdiction of certain wetlands must be determined on a
case-by-case basis.
Waters of the state, as defined under the Florida Air and Water Pollution
Control Acts (Florida Statutes, Chapter 403) includes, but is not limited to
"rivers, lakes, streams, springs, impoundments, and all other bodies of water
including fresh, brackish, saline, tidal, surface or underground. Waters
owned entirely by one person other than the state are included only in regard
to possible discharge on other property or water." (FS 403:031).
Wetlands Policy
Wetlands contiguous to another body of water would be considered a part
of that water body and would possess the same water quality standards.
However, it is recognized that certain portions of waters of the state
(particularly wetlands) do not meet specific water quality criteria due to
man-induced or natural causes. Most frequent wetlands "violations" occur for
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5.2.2 Continued
pH and dissolved oxygen. Under Section 17-3.031 FAC (Site-Specific Alterna-
tive Criteria) alternative water quality criteria may be applied based on
designated water use, extent of biota adaptions to the background conditions,
evidence of ecological stress and adverse impacts to adjoining waters.
Site-specific alternative criteria offer permanent relief under a given set
of background conditions.
Exemptions to specific water quality criteria are also granted for the
experimental use of wetlands for low-energy wastewater recycling. Under
Section 17-4.243(4) FAC (Exemptions from Water Quality Criteria), exemptions
from certain criteria may be granted upon petition indicating that the
appropriate criteria will not adversely affect public health or adversely
impact the biological community in the receiving waters or the contiguous
water body. With this exemption, appropriate criteria are not necessarily
the background levels. In addition, an exemption has to be renewed every
five years based on long-term monitoring data, whereas alternative criteria
(Section 7-3.031 FAC) provide permanent permit conditions. These exemptions
are provided to encourage experiments designed to lead to the development of
new information concerning wastewater disposal to wetlands.
Additional requirements concerning loading rates and treatment levels are
usually applied to wetland discharges (Thabaraj 1982). Hydraulic loading
rates are usually resticted to 0.5 to 1.0 inch per week. Minimum treatment
required would be secondary treatment (Chapter 17-6 FAC) followed by disin-
fection and storage in a holding pond (with a detention time of three days at
design flow) to achieve dechlorination. Nitrification before discharge would
be necessary to optimize nitrogen removal in wetlands where the ambient pH
level is not conducive for nitrification. Pretreatment to remove phosphorus
would also be necessary for flow-through wetlands unless site-specific infor-
mation is available to indicate long-term storage by the wetland sediments.
These above requirements can be modified based on consideration of the type
and ambient water quality of the downstream water body. In addition, some
form of legal control of the wetland would be necessary in order to restrict
public access to the site.
Wasteload Allocations/Effluent Limitations
The assimilative capacity of wetlands for nutrients, organics and metals
are site-specific and primarily dependent on hydological regimes. Standard
water quality models are not generally applicable to wetlands, and as a
result, FDER has not used predictive modeling to assess the potential impacts
of wastewater discharges on wetlands. In instances where ambient conditions
warrant site-specific criteria or exemptions, baseline water quality studies
are used to determine the appropriate criteria. It is the responsibility of
the discharger to design, construct and operate the permitted treatment and
disposal system to maintain the revised criteria in the wetlands (Thabaraj
1982). At this time, Florida has not been granted authority to administer
the NPDES permit program.
Monitoring Requirements
When exemptions to water quality criteria are granted to provide for
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5.2.2 Continued
wetland discharges, state regulations require the implementation of various
experimental controls to monitor the long-term ecological effects and waste
recycling efficiency. Monitoring of the significant chemical and biological
parameters, including control systems, is required to insure that the
applicable water quality criteria are met. Monitoring requirements vary from
site to site and may include the usual parameters (pH, dissolved oxygen,
suspended solids, etc.) in addition to more specific parameters such as
chlorides/sulfates, fecal streptococcus, benthic macroinvertebrates, and
possibly annual aerial infrared photography and vegetation species distribu-
tion surveys.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.3 Georgia
GEORGIA REQUIREMENTS FOR WETLANDS DISCHARGES DO NOT DIFFER
FROM OTHER WASTEWATER DISCHARGES
The Georgia Environmental Protection Division (EPD) does
not distinguish wetlands from other waters of the state
for the purpose of permitting wastewater disposal. How-
ever, permit limitations for wetland discharges are set
based on qualitative analyses rather than predictive
modeling. Georgia was authorized to administer its NPDES
permit program in 1974.
Definition
Section 17-503 of the Georgia Code defines waters of the state as "all
rivers, streams, creeks, branches, lakes, reservoirs, ponds, drainage sys-
tems, springs, wells, and all other bodies of surface or subsurface water,
natural or artificial, lying within or forming a part of the boundaries of
the state which are not entirely confined and retained completely upon the
property of a single individual, partnership, or corporation." Georgia EPD
does not distinguish wetlands from other waters of the state for the purpose
of permitting wastewater discharges.
Wetlands Policy
The Georgia EPD does not have an official policy concerning the discharge
of treated wastewater to wetlands. Georgia water quality regulations recog-
nize that certain natural waters of the state may have a quality that will
not be within the criteria of the regulations. In addition, a provision in
the regulations allows for the incorporation of "alternative effluent limi-
tations or standards where warranted by 'fundamentally different factors."'
(Section 391-3-6.06 Waste Treatment and Permit Requirements). It should be
noted, however, that alternative effluent standards do not constitute
exceptions to the water quality criteria.
Wasteload Allocations/Effluent Limitations
Water quality criteria and permit limitations for wetland discharges are
usually established on a case-by-case basis depending on the treatment facil-
ity, the size and nature of the wetland and the water quality conditions.
Permit requirements are based on federal effluent guidelines, secondary
treatment, or some degree of treatment more stringent where it is necessary
to achieve and/or maintain the water quality standards. The Georgia EPD does
not use predictive modeling to establish effluent limitations for wetland
discharges but instead relies on site analyses and qualitative judgements
(Welsh 1982). Certain wetland systems such as swamp creeks might be modeled
if a defineable channel exists. In this situation, however, the discharge
would not be considered a wetlands discharge under current policies.
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5.2.3 Continued
Monitoring Requirements
Monitoring requirements for wetland discharges do not generally differ
from other wastewater discharges. However, monitoring requirements are not
specifically outlined in the Georgia regulations; provisions are established
to allow the Georgia EPD to require additional monitoring, recording and
reporting as may be determined appropriate. Generally, Georgia dischargers
are required to monitor BOD, total suspended solids and flow.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.4 Kentucky
NO WETLAND DISCHARGES ARE CURRENTLY PERMITTED IN KENTUCKY
The Kentucky Division of Water (DOW) administers the water
quality programs in Kentucky. Wetlands are not
distinguished from other waters of the Commonwealth, and
wetland discharges have not yet been permitted. However,
provisions are available for case-by-case analysis of
wetland discharges. Kentucky has not yet been granted the
authority to administer the NPDES permit program.
Definition
The Kentucky DOW does not differentiate wetlands from other waters of the
Commonwealth. "Waters of the Commonwealth" are broadly defined in the
Kentucky Environmental Protection Law (KRS, Chapter 224) as "any and all
rivers, streams, creeks, lakes, ponds, impounding reservoirs, springs, wells,
marshes and other bodies of surface or underground water..." Wetlands are
further identified and classified by the Kentucky Department of Fish and
Wildlife using the FWS classification system (Cowardin et al. 1979).
Wetlands Policy
Since wetlands are not distinguished from other waters of the Common-
wealth, a specific policy concerning wastewater discharges to wetlands has
not been developed by the Kentucky DOW. However, wastewater discharges,
either industrial or domestic, are not expressly prohibited to any waters of
the Commonwealth, with the possible exception of certain outstanding resource
waters. Application for discharge to a wetland would be reviewed on a
case-by-case basis with input from the Kentucky Department of Fish and Wild-
life and the Kentucky Nature Preserves Commission.
Kentucky regulations provide for variances to certain classification
criteria when demonstrated that the applicable criteria are not attainable
due to naturally occuring poor water quality. Determinations of appropriate
criteria are made on a case-by-case basis and are subject to review at least
every three years (401 KAR 5:029, Section 9).
To date, Kentucky has not permitted any discharges of treated wastewater
to wetlands.
Wasteload Allocations/Effluent Limitations
Since no wetlands discharges have been permitted in Kentucky, a procedure
for assigning effluent limitations has not been tested. However, the Ken-
tucky DOW has indicated that stream segments that are characterized as
marshes are assumed to respond as natural channels under critical flow
conditions. Under this assumption, wetlands would be modeled similarly to
any other free flowing stream segments using DOW's broad based general dis-
solved oxygen model (domestic discharges). Industrial discharge limitations
would be developed on a case-by-case basis.
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5.2.4. Continued
Monitoring Requirements
General provisions are included in the Kentucky Waste Discharge
Regulations (40 1 KAR 51005, Section 9) to provide for effluent monitoring
and reporting. The type and frequency of analysis may be specified on the
permit, allowing for special considerations for wetlands should the need
arise.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.5 Mississippi
BAYOU AND OXBOW LAKE DISCHARGES ARE EVALUATED QUALITATIVELY
Most apparent wetland discharges 1n Mississippi are to
bayou and oxbow lake systems. Discharges to these systems
are evaluated qualitatively on a case-by-case basis.
Provisions are available for establishing specific water
quality criteria and monitoring requirements. The State
of Mississippi was granted authority to administer its
NPDES permit program in 1974.
Definition
Wetlands in Mississippi are considered waters of the state, which are
defined as "all waters within the jurisdiction of this State, including all
streams, lakes, ponds, impounding reservoirs, marshes... and all other bodies
or accumulation of water surface and underground... except lakes, ponds, or
other surface waters which are wholly landlocked and privately owned." (MPC
3-74). The Mississippi Bureau of Pollution Control (MBPC) further defines
and delineates wetlands using the Corps of Engineers definition (see Section
t- • 1 / •
Wetlands Policy
The State of Mississippi does not distinguish wetlands from other waters
of the state for the purpose of permitting wastewater discharges. When deter-
mining appropriate water quality criteria, the MBPC considers whether the
wetland is isolated or contiguous to other state waters. At a minimum, the
state applies Fish and Wildlife Service criteria, establishing minimum levels
for various water quality parameters. However, it is recognized that certain
waters of the state may not fall within desired or prescribed limitations due
to natural background conditions or irretrievable man-induced conditions.
Under these circumstances, exceptions can be made to the standard water
quality criteria.
Wasteload Allocations/Effluent Limitations
Wasteload allocations and effluent limitations for wetland discharges in
Mississippi are established in the same manner as for other discharges. When
a discernable channel and flow exist, a standard stream model is applied.
However, many apparent wetland discharges in Mississippi are to bayou and
oxbow lake systems, for which standard steady-state river models are
inappropriate.
For those systems determined unmodelable, qualitative evaluations are
made to estimate the effect of the proposed discharge. Water quality studies
are used to determine any existing water quality problems. Eutrophication
studies may be used to determine whether a proposed discharge will cause
significant increase in nutrient loadings. The relative size of the water
body to the discharge may also be considered.
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5.2.5 Continued
Mississippi was granted authority to administer its NPDES Permit program
in 1974.
Monitoring Requirements
Monitoring requirements for all permitted discharges are variable and can
be set by the State NPDES Permit Board. Requirements may include the
installation, use, and maintenance of monitoring equipment or methods,
including biological monitoring methods. Recording and reporting
requirements are also outlined in the state NPDES regulations. Generally,
wetland dischargers in Mississippi are not required to perform any additional
or specific monitoring.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.6 North Carolina
NORTH CAROLINA REGULATIONS RECOGNIZE DISTINCT WETLAND CHARACTERISTICS
The North Carolina Division of Environmental Management
(NCDEM) has jurisdiction over wastewater discharges In
North Carolina and has defined swamp waters for the
purpose of applying appropriate water quality standards,
primarily lower pH and dissolved oxygen levels. However,
the state does not have a specific policy concerning
wetland discharges; generally, stringent treatment levels
are applied in order to protect all standards in the
receiving water. North Carolina was granted authority to
administer its NPDES permit program in 1975.
Definition
Wetlands are recognized by NCDEM as specific water bodies and are
classified as swamp waters. Swamp waters are defined as "...those waters
which are so designated by the Environmental Management Commission and which
are topographically located so as to generally have very low velocities and
certain other characteristics which are different from adjacent streams
draining steeper topography" (NCAC 15-2B.0202). Swamp waters are categorized
as distinct water bodies for the purpose of applying appropriate water
quality standards; however, all true wetlands may not be categorized as swamp
waters. In some cases they may be classified as part of a contiguous water
body.
Wetlands Policy
The NCDEM does not have a specific policy to encourage or prohibit waste-
water discharges to wetlands. However, wetlands disposal is viewed as a
viable alternative and has been widely used throughout the coastal plain
river basins. State regulations recognize that natural waters may "have
characteristics outside of the limits established by the standards. Where
wastes are discharged to such waters, the discharger shall not be considered
a contributor to substandard conditions provided maximum treatment in compli-
ance with permit requirements is maintained..." (NCAC 15-2B.0205). Since it
may be impossible or impractical to bring the quality of the receiving waters
into complaince with the applicable water quality standards, variances from
the standards may be authorized.
Water quality standards are applied according to designated best-use cate-
gories. Swamp waters are recognized in every surface water classification
except Class A-l Waters (potable water supply). In every other surface water
classification, exceptions are made for swarnp waters in terms of pH and
dissolved oxygen; swamp waters may have a low pH of 4.3 and may have dissolv-
ed oxygen levels below 4.0 mg/1. All other appropriate water quality
standards are applied according to the designated classification. Discharges
to wetlands are not permitted as a buffering or treatment devices.
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5.2.6 Continued
Additional provisions in the state regulations pertain specifically to
the dissolved oxygen standards and nutrient sensitive waters. Specific
revisions to the dissolved oxygen standards may be granted for certain stream
segments for Class C waters where natural background conditions preclude the
attainment of a daily average dissolved oxygen concentration of 5.0 mg/1.
Treatment levels for discharge to these waters must be at least as stringent
as present waste treatment technology (NCAC 15-2B.0213). In addition,
certain waters may be classified as nutrient sensitive waters for the purpose
of controlling the growth of microscopic or macroscopic vegetation. For
waters classified as nutrient sensitive, no increase in phosphorus and/or
nitrogen over background levels will be allowed unless it is shown that the
increase is the result of natural variations, or will not endanger human
health or cause an economic hardship (NCAC 15-2B.0214). These provisions
could have a precise impact on the feasibility of using wetlands for waste-
water disposal; the dissolved oxygen revision could be used to permit wetland
discharges, whereas the nutrient sensitive designation could be used as a pro-
tective device.
Wasteload Allocation/Effluent Limitations
No specific provisions are made for determining wasteload allocations and
effluent limitations for wetland discharges. As with all other receiving
waters in North Carolina, predictive modeling is used to establish permit
limits. The standard Streeter-Phelps model is modified for wetland-type
systems. Variances may be granted for certain water quality parameters when
the natural background conditions warrant it. North Carolina was granted
authority to administer its NPDES permit program in 1975.
Monitoring Requirements
No specific monitoring requirements have been instituted for wetland
discharges. Monitoring requirements are established by regulation according
to the size of the treatment facility and the receiving water classification.
Additional tests and measurements may be required for certain industries,
based on the Standard Industrial Classifications.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2. State Policies and Regulations
5.2.7 South Carolina
WETLANDS DISPOSAL POLICY PERMITS DISCHARGES AS LAST OPTION
The South Carolina Department of Health and Environmental
Control (SCDHEC) has jurisdiction over all waters of the
state, including wetlands, for the purpose of permitting
wastewater discharges. A specific policy has been adopted
for the purpose of determining wasteload allocations for
wetland discharges. State regulations also recognize the
distinct differences of swamp waters. South Carolina was
authorized to administer its NPDES program in 1975.
Definition
Wetlands are considered waters of the state as defined under the South
Carolina Pollution Control Act (SCC Section 48-1-10 (2)) and, therefore, are
under the jurisdiction of the South Carolina Department of Health and
Environmental Control (SCDHEC) for the purpose of permitting wastewater
discharges. Swamp waters have been specifically defined for the purpose of
assigning wasteload allocations and permitting wetland discharges. As
outlined in the Summary of Methodology and Policies for Determining Stream
Assimilative Capacity and Developing Wasteload Allocations for Point Source
Discharges (SCDHEC, March 1981), swamp waters are defined as:
...those waters which have been exposed for a substantial
period of time to conditions which cause these waters to
have all of the following characteristics:
- Chemical and biological characteristics found in waters
which have been exposed for a substantial time to decaying
organic matter. For example, low velocity, low dissolved
oxygen, low pH, and a dark color.
Inundated land areas covered by trees and other
vegetation. This inundation occurs much of the year.
Wetlands Policy
Wetlands discharges are distinguished from other wastewater discharges
in South Carolina, and the SCDHEC has developed a policy specifically
concerning the determination of wasteload allocations for wetland discharges.
Wetland discharges are currently authorized only as a last resort when there
are no other reasonable alternatives. In addition, SCDHEC advises that the
wetlands should be owned by the discharger or that an easement should be
acquired.
The State Water Classification Standards System recognizes that some
natural waters may have characteristics outside the established limits.
Specific exceptions may be made in Class A and Class B waters where natural
conditions have lowered dissolved oxygen and pH levels. Separate numeric
221
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5.2.7 Continued
standards may be established for other waters which have natural conditions
outside existing standards; however, specific standards for wetlands have not
yet been established (Sansbury 1982).
SCDHEC recognizes that waters vary in their ability to assimilate
nutrient loadings. Therefore, nutrient loadings and specific nutrient
standards for waters are addressed on a case-by-case basis.
wasteload Allocations/Effluent Limitations
The policy adopted by the SCDHEC for developing wasteload allocations
recognizes the difficulties in defining average water quality conditions in
wetlands and in predicting the assimilative capacity of these waters. When
specific water quality data are not available to identify the impact of a
wastewater discharge to swamp waters, publicly-owned treatment facilities
will provide secondary treatment or comply with current EPA policy on treat-
ment greater than secondary. Privately-owned treatment facilities will
provide best available treatment (BAT) as defined by SCDHEC.
In some instances, a site investigation of a proposed wetland discharge
will indicate a drainage system that can be described with an appropriate
mathematical model. If so, modeling techniques will be used in setting a
wasteload allocation. In addition, higher winter effluent limits for ammonia
may be permitted on a case-by-case basis.
South Carolina was authorized to administer its NPDES program in 1975.
Monitoring Requirements
Under the South Carolina Pollution Control Act (SCC 48-1), the SCDHEC has
the power to require wastewater dischargers to install, use, and maintain
monitoring equipment or methods and to sample and analyze the effluent.
Generally, specific monitoring requirements are not estabished for wetland
discharges. Usually, only BOD, dissolved oxygen, temperature, total suspend-
ed solids, pH, ammonia and flow are required to be monitored.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.2 State Policies and Regulations
5.2.8 Tennessee
TENNESSEE DOES NOT HAVE A SPECIFIC POLICY CONCERNING WASTEWATER
DISCHARGES TO WETLANDS
The Tennessee Department of Public Health, Division of
Water Quality Control permits wastewater discharges to
wetlands associated with other water bodies. Predictive
modeling is used to determine wasteload allocations under
low flow and no flow conditions. Tennessee was granted
authority to administer its NPDES permit program in 1977.
Definition
Wetlands in Tennessee are considered waters of the state and as such are
under the jurisdiction of the Department of Public Health for the purposes of
protecting water quality and permitting wastewater discharges. Exceptions
are made for wetlands which are confined within the limits of private
property in single ownership and which do not form a junction with natural
waters (Tennessee Water Quality Control Act; TC 70-324).
Wetlands are further classified and delineated in Tennessee using the FWS
classification system (Cowardin et al. 1979). The COE definition is used for
regulatory purposes (404 permits).
Wetlands Policy
The State of Tennessee does not have a specific policy concerning waste-
water discharges to wetlands; however discharges are permitted to wetlands.
The Tennessee Water Quality Criteria state "the rigid application of uniform
water quality criteria is not desirable or reasonable because of the varying
uses of such waters." In addition, the assimilative capacity varies depend-
ing upon the volume of flow, depth of channel, rate of flow, temperature and
natural characteristics (Chapter 1200-4-3.01(2)). Therefore, the established
water quality criteria are considered as guides, and additional criteria may
be set to meet the needs of particular situations. Although considered as
guides, these water quality criteria have been determined to be legally
applicable and enforceable under state law.
Water quality criteria are established for specific use categories. Most
wetlands in Tennessee are designated for Fish and Aquatic Life (Bowers 1982).
Under this use category, the dissolved oxygen criteria is set at 5.0 mg/1
except where the natural background conditions are less than the desired
minimum. These exceptions to the dissolved oxygen limit are determined on a
case-by-case basis, but in no instance will the dissolved oxygen concentra-
tion be allowed to fall below 3.0 mg/1 (Chapter 1200-4-3.01(3)). The pH
criteria for Fish and Aquatic Life is set at 6.5 to 8.5, which may be higher
than that naturally associated with wetlands.
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5.2.8 Continued
Wasteload Allocations/Effluent Limitations
The Tennessee Division of Water Quality Control has not instituted spe-
cific procedures concerning wasteload allocations and effluent limitations
for wetland discharges. Generally, predictive modeling using a modified
Streeter Phelps model is used when a discernable channel is present; low flow
conditions are modeled and overbank flooding to associated wetlands is
ignored. When the flow is slow or nonexistent, or when a distinct channel is
not distinguishable, a lake model is used.
The Tennessee Water Quality Control Board has adopted general and
specific requirements for effluent limitations (Chapter 1200-4-5). Effluent
limitations for effluent limited and water quality limited stream segments
have been adopted in conformance with the Federal Water Pollution Control
Act.
Monitoring Requirements
No specific monitoring requirements have been established for wetland
discharges in Tennessee. Monitoring and reporting requirements can be set on
a case-by-case basis, allowing for modifications on an individual basis.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.3 Wetlands Discharge: Treatment or Disposal
THE TREATMENT/DISPOSAL ISSUE IS IMPORTANT TO IMPLEMENTATION
OF WETLAND DISCHARGES
The consideration of wetlands discharges as either treat-
ment or disposal has specific implications on regulating
discharges. Currently, wetlands are considered part of
the waters of the United States and as such cannot be used
in lieu of secondary treatment.
As currently defined, wetlands are considered waters of the United States
(40 CFR 122.3). Therefore, whether a wastewater discharge is considered as
disposal or as part of the treatment process has several specific implica-
tions. As waters of the United States two criteria must be met: 1) A
minimum of secondary treatment is required for discharges, and 2) established
US^SMnnrctheSe Waters must be mair)tained through the water quality standards
and NPDES permitting programs.
Some have suggested that wetlands, due to their inherent ability to
renovate wastewater, serve as part of the treatment process and should be
considered as such. This would allow permitting difficulties associated with
wetlands dischargers (effluent limitations) to be bypassed. However as
waters of the United States, wetlands cannot be incorporated as part of the
treatment process. Therefore, under their current status, wetlands must be
assessed for their capacity to dispose of wastewater effluent as any other
itrCci VI nCj WGt G P•
Wetlands research projects conducted to assess the use of wetlands for
wastewater discharges have evaluated wetlands to determine the degree of
treatment received and have considered wetlands to be a part of the treatment
process. In the case of the University of Florida project that discharged to
cypress domes, the wastewater had received secondary treatment prior to
discharge. The cypress domes were being studied for their capability to
provide additional wastewater renovation. In certain other cases in Region
IV where municipalities were discharging raw or primary effluent, wetlands
discharges were considered to be both a means for treatment and disposal. In
this context, it is clear that wetlands systems provided a degree of
treatment and, therefore, were part of the treatment process. For small
communities, wetlands discharges may provide benefits in conjunction with
conventional treatment processes.
Conversely, some existing municipal discharges to wetlands were likely
treated5waSfpi^S fpensiv* me,thot°f disposal by discharging only nominally
treated wastewater to a wetland. This is true for discharges begun several
years ago when wetlands were not considered to be valuable ecosystems. Prob-
lems associated with considering a wetlands discharge as only a disposal
m tPelJteit0K dejerminin9 meaningful effluent 1 imitations and disre-
potential benefits resulting from natural assimilative processes in
f ntJ1mitati°ns are typically based on modelling, but with
a hvdronpHnHc Th " ^T"6^ f]ows> "ndefineable channels and season-
al hydropenods, the capability to assign meaningful effluent limitations is
constrained.
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5.3 Continued
With the recently proposed revisions to the water quality standards
regulations, greater flexibility in addressing the treatment/disposal
question is likely. Concepts of use attainability, site-specific criteria
and benefit-cost analysis provide the institutional framework to better
address the subtleties of discharges to wetlands. A minimum of secondary
treatment, as currently required for waters of the United States has not been
shown to be an unreasonable predisposal condition. This requirement may be a
reasonable level of pretreatment unless a wetland is to be removed from the
public domain and fully dedicated to treatment alone. Recent amendments to
the Clean Water Act that defines oxidation ponds, lagoons, ditches, and
trickling filters as the equivalent of secondary treatment (when water qual-
ity will not be adversely affected) add flexibility in meeting a secondary
treatment predisposal requirement.
The revision or modification of uses and the establishment of
site-specific criteria to meet water quality standards will be the key
institutional mechanisms involved in discharges to wetlands. Use of a
wetland for wastewater management must be consistent with the other estab-
lished uses of a wetland. The maintenance of these other established uses
will be achieved through NPDES permitting and water quality monitoring
processes.
Phase II of the EIS will further explore the treatment/disposal question
and will consider institutional options that are available in addressing this
issue. Regardless of whether a discharge is considered treatment or dis-
posal, wetland functions and values should be maintained and assimilative
capacities should not be exceeded.
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5.0 INSTITUTIONAL CONSIDERATIONS
5.4 Existing Implementation Problems
TECHNICAL AND LEGAL QUESTIONS MAY IMPEDE IMPLEMENTATION
Increased implementation of the use of wetlands for
wastewater disposal requires further clarification of
several legal and institutional issues. These issues
concern wetlands ownership and proprietary rights,
effluent limitations, wetlands definitions, and the need
for evaluative criteria.
Of the eight states in EPA Region IV, only two, Florida and South
Carolina, have officially recognized wetland discharges as being distinct
from other surface water discharges. North Carolina has defined swamp waters
for the purpose of applying appropriate water quality criteria but has not
instituted a formal policy for permitting wetland discharges. The initial
step towards instituting the use of wetlands for wastewater disposal (aside
from a basic understanding of the natural systems) involves a recognition of
wetlands as distinct systems. This recognition requires a specific defini-
tion of wetlands, leading to the development of official policies and analy-
tical tools for establishing effluent limitations. Finally, the question of
ownership and proprietary rights must be addressed to avoid legal problems.
Wetlands Policies
Wetlands definitions need to be developed before a comprehensive wetlands
disposal policy is formulated. An official definition of wetlands is neces-
sary to establish jurisdictional limits and provide a basis for applying an
official wetlands discharge policy.
Only Florida has defined the "landward extent of waters of the state"
using a detailed species list. North Carolina and South Carolina have
defined swamp waters in a general manner in terms of water quality but do not
provide for an accurate delineation of wetland areas. Other states in EPA
Region IV consider wetlands as waters of the state but do not provide a
specific definition nor allow for precise delineation. Several states define
wetlands for the purpose of permitting Section 404 Dredge or Fill Permits
(COE definition, see Section 2.2.2) or for fish and wildlife management
purposes. These definitions may be adapted for the purpose of permitting
wastewater discharges, provided consideration is given to appropriate water
quality parameters.
Wetlands are most appropriately defined at the state level because of the
variability of wetland types throughout the region. Each state needs a
definition which will best address the natural systems in that state and the
regulatory requirements of state agencies. H6wever, attention must also be
paid to the need for regional consistency. Definitions should be consist-
ently applied from one state to another within the framework of the Federal
Water Pollution Control Act and EPA regulations and guidelines.
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5.4 Continued
Wasteload Allocations/Effluent Limitations
Currently in EPA Region IV eight different methods exist for determining
wasteload allocations and effluent limitations for wetland discharges. From
the state perspective, difficulties may be encountered when applying models
which may not be precisely appropriate or using qualitative analyses which
limit consistency. When technological guidelines are followed, consistency
in application may be achieved at the expense of individual dischargers by
possibly requiring treatment levels that, in some cases, are unnecessarily
stringent. The use of models and qualitative analyses may allow recognition
of the variability of wetland systems but may not provide adequate protection
of the natural system. On the other hand, when low-flow conditions are used
as a basis for effluent limitations, valuable assimilative capacity may be
ignored, again resulting in unnecessarily stringent treatment levels.
From a regional perspective, different methods of permitting wetlands
discharges may limit consistency of wetlands use and protection. Treatment
levels permitted in one state may not be allowed in another, creating
economic inequities and inefficient resource use. At the same time, the
regional variability of wetland systems must be recognized and accounted for
while maintaining consistent application of a regional wetlands discharge
policy. In fact, the feasibility of a regional wetlands discharge policy
must be examined in view of the differences in wetland systems and the
different permitting methodologies.
Evaluation Criteria
Before wetland discharges can be widely implemented, evaluation criteria
are necessary to determine the effectiveness of permitted treatment levels.
In terms of water quality, it is difficult to determine when a wetland system
has been degraded by effluent discharges. A change in species composition
(vegetation) or reduced growth or loss of vegetation may indicate stressed
conditions; however, irreparable damage may occur before such overt changes
are noted. Certainly, evaluation criteria will vary between wetland types.
Still, these criteria are needed to balance wetlands use and protection.
Ownership/Proprietary Rights
In contrast to distinct water courses, wetlands can be, and in many
instances are, privately owned. The question of private ownership and pro-
prietary rights has distinct implications on the use of wetlands for waste-
water disposal, as illustrated by an example in South Carolina. Litigation
is currently underway in South Carolina pertaining to damages to a privately
owned wetland allegedly resulting from a permitted wetland discharge from the
town of Andrews. A private landowner is suing the State of South Carolina
for the loss of harvestable timber on his land. The plaintiff contends that
the cause of his timber loss relates to the permitted discharge and that the
State is responsible because it issued a permit for the discharge. As a
result of this case, the State has adopted a policy to require, as a precon-
dition to a wetlands discharge permit, ownership of the wetland to be used or
an easement from the owner.
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5.4 Continued
While the question of ownership and proprietary rights has not been faced
in any other state, Florida is the only state that has specifically addressed
this issue. Legal control of the wetland to be used (ownership, lease,
easement, etc.) is required before a permit to discharge is issued in
Florida.
Additional questions related to ownership include the extent of ownership
to be required and additional uses of the wetland. Due to the unpredictable
flow associated with wetlands, it is difficult to delineate the area that may
be potentially affected by an effluent discharge. This determination must be
made to establish ownership requirements and avoid legal problems similar to
the town of Andrews, South Carolina. Additional uses of wetlands used for
wastewater disposal may need to be limited. Florida requires posting of
wetlands used for effluent disposal to restrict public access. Potential
public health effects need to be determined before wetlands used for effluent
disposal can also be used for recreation, including the consumption of fish
and wildlife from these areas. In addition, the harvesting of timber from
these wetlands may need to be restricted to insure continuation of the wet-
lands' assimilative functions. Limitations on the use of privately owned
wetlands due to wastewater discharges may have to be compensated by the state
or discharger.
The question of EPA funding the purchase of wetlands needs to be
addressed in conjunction with the ownership issue. If wetlands are included
as an integral component of the wastewater treatment and disposal alterna-
tive, can EPA funding be used for the purchase of the wetlands? Land costs
associated with land application systems may be eligible for EPA funding;
does the same principle apply to the use of wetlands? These questions have
an important bearing on the future implementation of wetland discharges and
need to be addressed on the regional and national levels.
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SECTION 6
ENGINEERING CONSIDERATIONS
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6.0 ENGINEERING CONSIDERATIONS
ENGINEERING CRITERIA STILL IN DEVELOPMENTAL STAGES
The primary goal In the design of a wetlands-wastewater
system is to enhance the treatment capabilities of the
wetland while protecting its environmental values and func-
tions. Several wetlands wastewater disposal systems have
been studied in recent years. Design criteria are being
developed more rapidly for artificial systems than for
natural systems.
The objective of this section is to assess engineering considerations
associated with facilities for discharging wastewater to natural and arti-
ficial freshwater wetlands within Region IV. Engineering considerations
include facilities planning, design, installation, and operation and
maintenance (O&M).
Engineering considerations are important to the implementation and
proper functioning of wetland disposal systems. Three major areas of
importance are addressed:
Potential engineering problems
Planning, design, installation, and O&M criteria noted from existing
wastewater disposal systems to wetlands
Incomplete or missing criteria.
Generally, more is known about the design and performance of artificial
wetlands and aquaculture systems than natural wetland systems. Artificial
wetlands are those areas that become wetlands only with supplemental,
engineered inputs of water. Within these areas, additional wetland habitat
is created. Operation and maintenance procedures such as plant harvesting
and altering water levels can be included as part of the design of a
wastewater-wetland system. Volunteer wetlands is a term sometimes utilized
to denote irrigated fields or lagoons that become wetlands as a result of
applying wastewater to an area or some other form of hydrologic modification.
Aquaculture systems refer to artificial wetland areas operated for mul-
tiple purposes often including biomass production and perhaps energy produc-
tion as well as wastewater treatment. Five types of aquaculture-wastewater
systems have been tested: hyacinth, duckweed, common reed and cattail,
invertebrate, and fish pond systems. Hyacinth ponds are the most extensively
studied because of their high biomass production. However, the geographic
ranges of duckweed, reed and cattail ponds are more expansive as they can
tolerate wider temperature fluctuations (Wolverton and McDonald 1981). Aqua-
culture-wastewater systems utilizing invertebrates or fish are considered to
be in the exploratory/developmental stage and not ready for widespread use.
In addition, aquaculture systems involving animals are generally less effi-
cient in treating wastewater, require more land area, and are more difficult
to control than plant systems (Schwartz and Sin 1980).
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6.0 Continued
Issues of Interest
• Can a single set of preliminary design considerations for costs, system
configurations, treatment potential, and system operation be usefully
defined for wetlands-wastewater systems?
• Are costs favorable compared to other wastewater treatment methods?
• How are wetland-wastewater systems installed without damaging the
wetland?
• What type of monitoring activities should be conducted to assure the
proper operation of the system and the condition of the wetland?
t Can too much wastewater adversely affect wetland conditions?
• How long can a wetland-wastewater system be expected to function
properly?
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
VEGETATION AND HYDROLOGY IMPACT DESIGN CRITERIA
Physical and biological characteristics of wetlands
influence design since hydrologic processes and vegetation
type largely control renovation of wastewater. Artificial
wetlands can be designed to optimize such characteristics.
Physical characteristics of natural and artificial wetlands differ,
although planning considerations are quite similar. The many planning
considerations for both natural and artificial wetlands have been segregated
into eight categories; one category is addressed in each of the eight
portions of Section 6.1.
Distinguishing physical, biological and chemical characteristics of
wetland systems have been presented in earlier sections. Those charac-
teristics relevant to engineering considerations are:
- The variety and assemblage of vegetation types
- Water patterns as existing within channels or as sheet flow over the
entire wetland surface area
- Natural wetlands can be hydrologically open (connected to lake or stream)
or closed (isolated such as a bog)
- Water from a wetland area may discharge to a nearby water body; percolate
downward during drier periods; evaporate; or be transpired, by plants.
Artificial wetlands including aquaculture systems can be purposely
designed with fewer types of vegetation than natural wetlands and more
predictable flow patterns. The only physical restriction is that an
artificial wetland area must be relatively level and able to pond water;
otherwise, the area will function as a more conventional land appliction
system. Significant components of an artificial wetland are: 1) plant
species utilized, 2) spacing and diversity of vegetation, 3) the extent to
which wastewater is disposed by downstream discharge, percolation to water
table, transpiration by plants, and evaporation, and 4) detention time.
Possible types of artificial methods are presented in Table 6.1.
To design properly a wetlands-wastewater system, the proposed use of the
wetland must be clarified. This should be done in conjunction with site
selection since the type and size of available wetlands impact design
considerations. While information regarding pre-treatment requirements and
allowable loadings is increasing for some wetlands systems, information for
design criteria is still limiting. Finally, cost analyses are important in
determining the feasibility of a wetlands discharge. The major component of
cost analyses relates to the distance to and size of available wetlands.
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Table 6.1. Artificial Wetlands Used for the Treatment of Wastewater.
Type
Description
rv>
Freshvater
Marshes
Marsh-pond
Pcids
Tr ?nch
Trench (lined)
Aqi aculture
Areas with semi-pervious bottoms planted with various wetlands plants such
as reeds or rushes.
Marsh wetlands followed by pond.
Ponds with semi-pervious bottoms with embankments to contain or channel
the applied water. Often, emergent wetland plants will be planted in clumps
or mounds to form small sub-ecosystems.
Trenches or ditches planted with reeds or rushes. In some cases, the trenches
have been filled with peat.
Trenches lined with an impervious barrier usually filled with gravel or sand
and planted with reeds.
One or more basins or ponds with one or more species of aquatic plants (e.g.,
water hyacinths, duckweed, or reeds and cattails) and/or stocked with inverte-
brates or fish. As wastewater is treated, biomass can also be harvested and
utilized for food or energy production.
Source: Tchobanaglous and Gulp. 1980, except for aquaculture description.
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.1 Proposed Use of Wetlands
WETLANDS CAN BE MANAGED FOR THE ASSIMILATION OF POINT AND NONPOINT
POLLUTION SOURCES
Wetlands serve many functions for the direct benefit of
society. They can be further managed to enhance these
benefits although proper protection and maintenance become
crucial under such conditions, particularly when
considering wastewater discharges.
The most basic planning analysis is to determine how a wetland area is to
be utilized. In other words, what types of flows (wastewater, runoff, flood
water) are to enter the wetland area. Such a decision must be made on a
site-by-site basis; subsequent engineering activities are based on this
assertion.
Potential engineered uses of a wetland area include: wastewater treat-
ment, wastewater disposal, both wastewater treatment and disposal, runoff
treatment and/or disposal, creation of habitat for plants and animals, flood
control, drought inhibition, biomass production for animal feed or energy,
and resource recovery. A number of technical factors enter into this first
planning-level decision:
- the nature of the effluent (e.g., the presence of industrial by-products)
- the level of pre-treatment prior to discharging wastewater to a wetland
- the frequency and duration of discharges (e.g., to be disposed seasonally
or year-round)
- the sensitivity of downstream rivers, lakes or streams to pollutant
loadings
- adjoining land uses
- the amount of runoff from areas farther upstream
- the amount of contaminants input from upstream sources
- environmental impacts resulting from diverting runoff from areas farther
upstream
- the susceptibility of local wildlife to habitat alteration
- the need for additional wetland habitat or regeneration of degraded
wetlands
- the susceptibility of downstream areas to flooding
- the potential significance of the wetland for drought inhibition
(relative to the overall potential for a drought to occur and drought
ramifications)
- the potential for biomass production which could also be utilized
economically for energy production or feed.
Those wetland treatment systems specified to have multiple aquaculture
components in a single unit or that combine with other aquaculture or conven-
tional units to form a process are called combined systems. If combined
systems are to be employed, another factor to consider is the relative lack
of rational design criteria. It is difficult to optimize the aquaculture
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6.1.1 Continued
units of combined systems for both wastewater treatment and biomass/protein
production in the same unit (Reed, Bastian and Jewell 1982).
Structurally, several options are available for implementing wetlands
management:
- Little or no modification to a wetland area would allow runoff and
floodflows to continue to enter and exit the area.
- A wetland area can be controlled hydrologically by constructing earth
dikes around the perimeter. Flow paths can be modified adjacent to the
wetland area to allow extra water which previously entered the wetland
area to be controlled without drainage or scouring problems.
- Wastewater flows entering a wetland area as surplus flows can: 1)
percolate downward if underlying soils allow, 2) be released from the
downstream portion of the wetland area, or 3) increase water depths
within the wetland area. This decision regarding the ultimate method of
wastewater disposal will depend primarily upon downstream water uses and
wetland area characteristics.
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.2 Site Selection
SIZE, TYPE AND ACCESSABILITY OF NATURAL WETLANDS IMPACT SITE SELECTION
The site selection process proceeds from very general
considerations to detailed site selection suiWc
w~t™tnt W6tland 8reas can have «Slfl«?t ly ^^rt
5£SX?« m\na9ement capabilities and different
sensitivities to wastewater flows. The size tvn* *n*
accessability of available wetlands are important? '
™ d^n of • preferr?d ""land area for WWTP
ST -*
assess the
area
the^time period during Bh1ch a discharge to the wetland area would take
source of wastewater
g»te..t.r loading rates In gallons (or pounds) per acre per day (Secti
on
are
wastewater (Fritz and HeHe 1978) PTh """"^"S larger quantities of
a,d ultimate,,, the ^ Lsl Jill""'/ a ™' 0"S "°Uld ""^ "'*'
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6.1.2 Continued
Climate may be the most important consideration when evaluating sites
for the use of an aquaculture system. Water hyacinths grow most rapidly in
waters with temperatures between 28° and 30°C (82-86°F). Hyacinth growth
ceases if water temperatures are below 10°C (50°F) or above 40°C (104°F).
Hyacinth leaves are destroyed if air temperatures of -3°C (27°F) are exper-
ienced for 12 hours; the plants are killed entirely if air temperatures of
-5°C (23°F) are experienced for 48 hours. Hyacinths are able to grow
year-round only in southern Florida. Within the other areas of the Southeast
where hyacinths exist, growth occurs for seven to ten months each year.
Transparent covers placed over the plants can extend the growing season
(O'Brien 1981). Duckweed, reeds and cattails have a wider range of tem-
perature tolerance than water hyacinths. Duckweed is able to grow at water
temperatures greater than 1° to 3°C (33 to 37°F).
Artificial wetlands (much like land treatment systems) can potentially
be built nearly anywhere, given appropriate (or in some instances
substantial) engineering input and capital (Bastian 1982). Site selection
processes should include the ultimate level of construction necessary to
achieve treatment goals.
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.3 Alternative Physical Configurations
THE ENGINEERING CONFIGURATION FOR THE USE OF WETLANDS IS IMPORTANT TO
OVERALL WASTEWATER MANAGEMENT EFFECTIVENESS AND TO NEARBY LAND USE
Engineering activities can Influence the mechanisms by
which discharges enter and leave a wetland area, waste-
water treatment and storage configurations, and flow
patterns within a wetland area.
Wastewater discharges to and from a wetland area can be designed as 1)
one point source, 2) a number of point sources, or 3) overflow/runoff from a
storm or intentional discharge. The selection of a preferred discharge
configuration will depend primarily upon costs, other uses of the wetland
area, and upon activities further downstream.
Costs, installation impacts, operation impacts, energy requirements, and
operation and maintenance requirements, may limit the choice of discharge
configurations. In general, these limitations are less substantial for
artificial systems because artificial systems are designed and constructed
specifically for wastewater treatment purposes and existing wetland habitats
are not impacted. Conceivable discharge system configurations include the
following:
Point discharge(s) at edge of wetland, gravity flow
Channel discharge at edge of wetland, gravity flow
Distribution within wetland, gravity flow
Distribution within wetland, spray flow
Treatment plant and storage configurations must also be considered. In
many cases, wetlands discharges are associated with existing treatment
facilities. However, in other instances treatment and/or storage facilities
may be required. In such cases, a treatment plant or storage basin could be
located adjacent to the wetland area, or adjacent to any other disposal point
(e.g., a stream or a conventional land application site). Factors involved
in this decision, in addition to costs, are:
locations of densely populated areas
extent to which discharges would be released to wetlands for locations
where other disposal options are available
age and suitability of the existing wastewater treatment plant
land availability
impacts of developing a new site for a wastewater treatment plant.
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6.1.3 Continued
Where possible, artificial wetlands and aquaculture systems should be
designed with a minimum of two units (ponds, basins, etc.) in parallel, each
having the capacity to treat average daily flow. This allows one unit to be
periodically taken out of service for routine maintenance and repairs.
Additionally, flow patterns within a wetland area can be altered to
improve wastewater management effectiveness or enhance some other objective
established for the wetland. Channels can be dredged, dikes added, growths
of vegetation can be controlled, and some form of dredging can be done to
achieve these objectives.
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.4 Pre-Treatment Requirements
THE DEGREE OF TREATMENT AND TYPE OF DISINFECTION ARE MAJOR CONSIDERATIONS
Primary wastewater treatment conducted within a
conventional wastewater treatment plant, instead of within
a wetland area, generally is cost-effective. Conventional
secondary treatment, however, may not be cost-effective in
a treatment plant compared to utilizing land application
the effluent needs
natp 3-MaSV 1W,hether the effluent needs to «* cn^r
nated (possibly followed by dechlorination) prior to its
release to a wetland area merits consideration.
ssffirss p~ ~
erations should be evaluated for different levels of pretreatment:
aheollutant in "*"*"' *"* ^stream areas to
effluent loadings from primary effluent than from secondary
°f hl9her 103din^ f- primary effluent
- removal of potentially toxic constituents prior to discharge.
wate^aDDlicaJinnrtn"5",16 ^ fu"'*^* ^search projects regarding waste-
°"
241
-------
6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.5 Allowable Wastewater Loadings to Wetlands
SITE-SPECIFIC CHARACTERISTICS AND COMPLEX PHYSICAL-CHEMICAL-BIOLOGICAL
MECHANISMS WITHIN WETLAND AREAS ARE IMPORTANT IN ESTIMATING
THE EXTENT OF NECESSARY WASTEWATER PRE-TREATMENT
Each wastewater constituent is affected, converted or
removed from the waste stream to various extents within a
wetland area. The variables and conversion mechanisms are
not entirely definable. A significant level of uncer-
tainty exists for estimating the capacity of a wetland
area to provide wastewater treatment for certain
constituents.
Most of the existing projects involving wastewater application to wetland
areas have physical dimensions and capacities based on the objective of
providing nutrient removal, particularly nigrogen and phosphorus removal.
The following key points with regard to nutrient removal in wetland areas are
taken primarily from Nichols (1981):
- Nutrient removal capability depends upon specific soil characteristics,
hydrologic conditions (based on hydraulic detention time of the
wastewater within the wetland area), types of vegetation, and wastewater
loading rates.
- Growth of wetland vegetation in general represents only a minor sink for
nutrients. In a Florida wetland, however, 43 percent of the applied
phosphorus from wastewater was taken up by cypress root tissue (Ewel and
Odum 1978).
- Natural wetlands receiving wastewater have had widely varying nitrogen
removal efficiencies.
- The length of time during which a particular type of wetland can remove
any wastewater constituent, particularly phosphorus, is not known.
- Nutrients can be flushed from a wetland area due to die-off of vegetation
and high runoff flows.
- Wetlands in warmer climates remove nutrients more efficiently. Also,
nutrients may be flushed in pulses as a result of storms, depending upon
a wetland's physical configuration.
- Certain types of vegetation are able to store and utilize nutrients
better than others. Stored nutrients that are not utilized are often re-
turned to the water upon death and decay of the vegetation.
- Some marsh systems apear to have a limited capacity for assimilating
nutrients (Steward and Ornes 1975).
- Nutrient uptake by plants varies seasonally.
242
-------
6.1.5 Continued
- Effective nitrogen removal can occur while phosphorus concentrations
remain at significant levels (Tuschall et al. 1981).
- Long-term removal of nutrients over a period of years is questionable
without harvesting vegetation or burning peat layers periodically.
Each of these must be considered when designing a wetlands system that
will maintain its function and assimilative capacity. Natural and artificial
wetland-wastewater systems can be operated to enhance nutrient removal, as
discussed in Section 6.4, by promoting percolation through soil and sub-
sequent denitrification within soil under anaerobic conditions. Maximum
nutrient removal for aquaculture systems is obtained in shallow ponds that
are harvested frequently.
A major difficulty in establishing allowable loadings to a wetlands area
relates to the varied mechanisms or pathways for the assimilation of pollut-
ants. Section 4.4 and its subsections describe nutrient cycles and assimila-
tive mechanisms of other pollutants. These are summarized in Table 6.1.5-a.
on
Detention time, the time period over which removal mechanisms can act ur
the wastewater, should also be considered when estimating allowable loadings.
Time-dependent mechanisms include suspended solids removal, BOD removal,
denitrification and nutrient removal. If the detention time is too low,
removal mechanisms will not be able to act long enough to achieve the desired
treatment level. Beyond a certain time period, however, removal efficiencies
will drop. Detention time is dependent on the volume and water budget of the
wetland area. The components of the water budget are illustrated in Figure
4.3.1. If the water budget is well defined, the desired detention time can
be maintained through changing conditions by control of wastewater inflow or
water depth. For example, in summer months when evapotranspiration is high
and detention times increase, reducing the liquid depth can bring detention
times down to the desired level. In natural wetlands, where the water budget
is hard to quantify, such control may prove more difficult.
The size of wetland areas needed to achieve treatment requirements will
depend on the allowable loading rate. For example, at a loading rate of 3
cm/wk (1.2 in/wk) a 946 cubic meters/day (0.25 mgd) community would require
22 hectares (54 acres) of wetland area. This result is based on 3 centi-
meters of wastewater being spread evenly over 22 hectares for a one-week time
period. Unfortunately, other factors are involved which complicate con-
siderations.
Acreage requirements vary with: 1) portion of land to receive
wastewater, 2) detention time specified for the effluent and 3) desired
water-wastewater depth as well as loading rate and percentage of time when
effluent is applied to a wetland. This can be represented by the following
equation:
Ar = (Qj + Qe)ti X (unit conversion factors)
D
and
243
-------
6.1.5 Continued
Ar = PAt
where
QT = net water inputs to a wetland other than wastewater
Qe = wastewater flow (e.g., mgd)
ti = desired detention time (e.g., days)
D = desired water depth of both effluent and other inputs
(precipitation, evaporation, runoff...)
Ap = wetland area receiving wastewater
At = total wetland area
P = portion of total wetland area receiving wastewater
Q-j, D and P could vary with time. Qe could also vary. The above equations
neglect infiltration to the underlying soil by Qi or Qe, although it can be
considered part of Qi (Metcalf and Eddy 1979).
For water hyacinth systems, organic loading rates and detention times are
similar to those for more conventional, wastewater stabilization ponds that
utilize untreated wastewater. Harvesting of hyacinth growth may be needed
for high performance levels as it is for high levels of nutrient removal
(Reed, Bastian and Jewell 1980). Wolverton has suggested that harvesting
should be conducted every five weeks during the warm growing season (EPA
1977).
Preliminary results from two hyacinth-wastewater systems in Florida indi-
cate that a final effluent can be produced that meets all advanced wastewater
treatment (AWT) requirements except the level of phosphorus. The difficulty
with removing phosphorus may result because the nitrogen-to-phosphorus ratio
of secondary effluent is slightly less than the same ratio in harvested
plants. Addition of nitrogen to a hyacinth pond may be a viable method for
correcting this problem. Other methods, not yet mentioned, for achieving AWT
treatment levels may include 1) additions of iron salts to prevent chlorosis
and 2) provision of facilities for phosphate precipitation if removal of
phosphorus is critical and not achieved by other means (O'Brien 1981).
Achieving high treatment efficiencies for a long period of time is
somewhat uncertain because no hyacinth systems have been operated for an
extended period of time. Proper O&M is essential for long-term operation.
Primarily, long term allowable loadings depend on the assimilative capa-
city of a wetland as well as on maintaining natural wetlands functions. This
depends in part on whether a system is hydro!ogically open or closed and
whether resulting changes in the wetland system are acceptable or unaccep-
table. From an engineering standpoint it will be difficult to establish
broad, quantitative guidelines. Site-specific characteristics of the
wastewater and wetland system will ultimately determine allowable loadings.
Such guidelines will be established in Phase II of this EIS.
Design criteria and associated removal (conversion) of wastewater consti-
tuents obtained from existing natural, artificial and aquaculture waste-
water-wetland systems within the southeastern United States are summarized in
Tables 6.1.5-b, 6.1.5-c and 6.1.5-d.
244
-------
Table 6.1.5-a Removal (Conversion) Mechanisms in Wetlands for the Contaminants in Wastewater
Contaminant Affected *
Mechanism
Physical
Sedimentation
Filtration
Adsorption
Chemical
Precipitation
Adsorption
Decomposition
Biological
Bacterial Metabolism2
Plant Metabolism2
Natural Die-Off
riman
term
v>
> v*
-Q v> KJ c -r- i- -t- v- cn .c o « j_ 3
T,"^Oi~ p a. >, «> o> O i— O I- S_ I. 4-> *r-
4J c/1 f— (/) O •*-> o cQzo-nio; oo
P S I I I I I I
s s
P P
P P S
P P
P P P
s s
P
Description
Gravitational settling of solids (and constituent
contaminants) in pond/marsh settings.
Particulates filtered mechanically as water passes
through substrate, root masses, or fish
Interparticle attractive force (van der Waals force).
Formation of or co-precipitation with insoluble compounds.
Adsorption on substrate and plant surfaces.
Decomposition or alteration of less stable compounds by
phenomena such as UV irratiation, oxidation, and reduction
Removal of colloidal solids and soluble organics by suspended,
benthic and plant-supported bacteria. Bacterial nitrifica-
tion/demtnfication.
uptake and metabolism or organics by plants. Root excretions
may be toxic to organisms of enteric origin.
Natural decay of organisms in an unfavorable environment.
•ncludes both biosynthesis and catabolic reactions.
Source: Tchobanaglous and Culp. 1980.
contaminant).
-------
Table 6.1.5-b
cn
Engineeri ,g Characteristics and Treatment Efficiencies for Various Aquaculture-Wastewater Systems in the Southeastern
United St tes.1
Engineering Characteristics
Location
Coral Springs,
Walt Disney
World, FL
Lakeland, FL
NSTL, MS
Lucedale, MS
Gulf port, MS
Biloxi, MS
Frojec Surface
Status Area, ha.
FL Field esting 0.5
(5 bas ns in series)
Experimental 0.1
(3 channels)
femons ration 0.4
(3 bas ns in series)
Field esting 2.0
(Singl' Cell Lagoon)
Field esting 3.6
(Single cell
facultative lagoon)
Water
Depth, m.
0.4
0.4
-
1.22
1.73
Field testing 0.28 1.83
(2 aerated lagoons in parallel
3 unaerated lagoons)
Field testing 0.07
1.5
Soil
Vegetation Sub;
Hyacinths
Hyacinths
Hyacinths
Hyacinths
Hyacinths
Hyacinths
Duckweed
Pre- Flow, cubic Surface Area
>trate Treatment meters per day Loading cm/wk
Secondary 380 0.82
(activated sludge)
Primary 190
Secondary 450 to 980
None 475
None 935
Secondary 1000
(aerated lagoons)
-------
Table 6.1.5-h Continued
-Pi
•-•j
Wetland Treatment Efficiencies
Location
Coral Springs, FL
Walt Disney
World, FL
Lakeland, FL
NSTL, MS
Lucedale, MS
Gulf port, MS
Biloxi, MS
Five-day
BOD
77
91
50 :o 90
93
86
72
57
Suspended
Solids
48
89
80 to 100
90
95
69
91
Total Total
Nitrogen Phosphorus Comments
96 67 15 to 20% of plants are
harvested every 4 weeks
Best harvesting pattern
not yet determined
75 to 85 38 to 40 Influent quality was better
than typical secondary effluent
Influent quality was 11 mg/1 BODg,
97 mg/1 TSS into aquatic system
Influent quality was 161 mg/1 6005
and 125 mg/1 TSS into aquatic
system
Influent quality was 50 mg/1
BOD5 and 49 mg/1 TSS into
aquatic system
Influent quality was 35 mg/1 BODs and
155 mg/1 TSS into aquatic system
NOTE: The reference for information presented in this table in US EPA, 1982 unless otherwise noted.
-------
Table 6.1.5-c Engineering Characteristics and Treatment Efficiencies for Various Natural or Artificial Wetland-Wastewater Systems in Region IV.
Location
Natural Wetlands
Whitney Park, FL
Wildwood, FL
Reedy Creek, FL
Clermont, FL^
Gainesville, FL
Jasper, FL
Waldo, FL4
Jacksonville, FL
Surface Water
Area, ha. Depth, m.
6 variable2
202
41 up to 1
0.8 variable
1.6 1.5
-
-
189.4
Vegetation
Cypres
Swamp
Swamp
Harsh
Cypress dome
Cypress swamp
Cypress strand
Swamp
Soil
Substrate
Organic muck
Duckweed
Native clay
Native soils,
Peat soil ,
Sandy clays
-
-
Pre- Flow, cubic
Treatment m/day
Secondary
Secondary
Secondary
muck
Secondary
sands
Package plant
Secondary
Primary
Secondary
230
946
7,570
-
95
-
-
285-368
Surface Area1
Loading cm/wk
2.7
0.33
13
-
1
6 to 7
-
gal/min
Hydraulic Deten-
tion Time, days
-
-
-
-
variable^
-
Ifiased on a 7-day pe' week operation
2Water depths are keft below the tops of cypress knees
3The Clermont, FL system is said to be more closely controlled than the Wildwood, FL system (US EPA 1981)
4This system has been in operation for over 40 years (EPA 1981)
5Storm runoff entering the wetland area reduces wastewater detention time to as low as 4 days; during dry periods wastewater detention time can
be as high as 64 days.
-------
Table 6.1.5.-c Continued
ro
-P»
10
o
Wetland Treatment Efficiencies, In percent
Five-day
Location BOD
Natural Wetlands
Whitney Park, FL
Wildwood, FL
Reedy Creek, FL
Clermont, FL
Gainesville, FL
Dulac, LA
Jasper, FL
Suspended Total
Solids Nitrogen
89
90
-
-
-
51
to 1.9 mg/1
as N
Total
Phosphorus
91*
984
-
94
90+
53
-
Comments
Reference is EPA, 1982
unless otherwise noted
Reference: Solan et al . 1n
Drew 1978
Fritz and Halle, 1978
Meo, Day and Ford 1975
Boyle Engineering Corp.,
March 1981
Waldo, FL
Jacksonville, FL
Fritz and Helle, US EPA 1979
87.0 61.8 CHgM-Hill Engineering.
No artificial wetland projects
have been reported in the literature
for the Southeastern U.S.
treatment efficiencies can be based on constituent concentrations or constituent loadings. The EPA 1982 reference
does not specify the basis.
-------
Table 6.1.5-d Performance of Polyculture Systems Utilizing Fish.
Source
Location
Period
Major Culture
Minor Culture
Flow (mgd)
Unit Area (acres/mgd)
Average Depth (ft)
Detention time (days)
Loading (Ib BOD5/acre/day)
(Ib TSS/acre/day)
Initial fish stocked (Ib/acre)
Net fish produced (Ib/acre/mo)
(Ib/lb BOD5 removed)
(Ib/lb TSS removed)
Coleman et al . 1974
Oklahoma
June-Oct., 1973
channel catfish
Tilapia
Minnows
1.0
26
3.9-4.3
35
7.8
23
27
34
0.2
0.06
Henderson. 1979.
Arkansas
Dec. 1978-July 1979
Silver and bighead ca
Channel catfish
Buffalofish
Grass carp
0.45
36
4.0
47
6.5
8.7
378
340
2.9
2.4
Performance: Influent - Effluent (% Removal)
BOD5 (mg/1)
TSS (mg/1)
Total N (mg/1)
NH3-N (mg/1)
N02-N
N03-N
Total P (mg/1)
Fecal coliform (no/100 ml)
pH
DO (mg/1)
24-6 (75)
71-12 (83)
7.04-2.74 (61)
0.4-0.12 (70)
0.96-0.16
2.31-0.29
7.97-2.11 (74)
1380-20
8.2-8.3
28.1-9.4 (67)
38.0-17.1 (55)
5.1-2.0 (60)
0.02-0.11
0.01-0.5
3.0-2.5 (17)
7.88-8.19
3.0-7.4
Source: Schaurtz and Shin. 1980.
250
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.6 Other Preliminary Design Considerations
LAND USE AND BACK-UP METHODS ARE OTHER CONSIDERATIONS
ASSOCIATED WITH SYSTEM DESIGN
Industrial wastes, septage, land values, storage facil-
ities, back-up methods, federal grant conditions, and
considerations unique to artificial wetlands are
presented. Factors important to the operation of
wetland-wastewater systems are also listed.
Preliminary design considerations that significantly affect costs,
environmental impacts and operability but that have not been previously
discussed are presented in this section. Some of these considerations are
directly associated with system design, while others are associated with
operation and maintenance.
The considerations directly associated with system design are as follows:
- The presence of industrial wastes within the wastewater can result in
significant adverse effects on a wetland area. These effects could
result in adverse environmental impacts and/or less efficient removal
(conversion) of wastewater constituents
- Work at a water hyacinth treatment facility at Bay St. Louis,
Mississippi, showed one particular industrial wastewater to be treatable
with water hyacinths (O'Brien 1980). The uniqueness of each industrial
waste would necessitate laboratory and pilot-scale testing before a
full-scale waste treatment facility could be implemented.
- Septage from on-lot wastewater systems could be applied to an artificial
wetland area once it undergoes primary treatment. Septage quality and
flow are preliminary design considerations
- The enhancement (or detraction) resulting from wastewater entering a
wetland area can alter the economic value of surrounding locations
- Storage facilities such as holding ponds can be utilized both to store
effluent during wet periods and to prevent unusually large, intense,
short-term flows from reaching wetland areas. With adequately large
storage facilities, wastewater can be applied to wetland areas in
consistent quantities as a function of time
- For long periods of time when no wastewater should be applied to wetland
areas, a back-up method of wastewater treatment or disposal would be
needed.
- EPA does have the option of imposing grant conditions in connection with
federal funding provided for a natural or artificial wetland-wastewater
251
-------
6.1.6 Continued
system. A grant condition could conceivably address any aspect of design
or O&M: pre-treatment requirements of water or nutrient balance cal-
culations, soil characteristics, land area requirements, surrounding land
use, vegetative cover, treatment efficiency, method of ultimate disposal,
monitoring requirements, or a directive to hire a biologist for operating
and maintaining the system.
Implementation of an artificial wetland system or aquaculture system
allows greater design flexibility than in a natural wetlands system. A
number of additional design considerations need to be evaluated for an
artificial wetland system:
- Two systems in parallel can be installed
- Various ecological communities can be utilized in series. For example,
two possible configurations are marsh-pond and meadow-marsh-pond. When a
variety of ecological communities are utilized, nutrient retention is
enhanced (Blume 1978). Ponds can also be provided in alternating
sequence. Different plant types could be purposely instituted to improve
wastewater treatment efficiency (also possible with "natural" wetlands).
- Flows can be spread uniformly over an area or channelized
- Vegetation can be harvested regularly.
- The Grass and Plants Interstate Shipment Act (Public Law 874) prohibits
interstate transport or sale of water hyacinths, alligator grass, water
chestnuts and seeds of these plants (O'Brien 1981). Therefore, within
Region IV of the EPA, water hyacinth-wastewater systems cannot be
installed north of Georgia, Alabama and Mississippi. In more natural
settings, these plants are considered to be great nuisances.
Operational factors that can also be relevant to preliminary design
considerations are:
- energy required to pump wastewater into a wetland area and/or to harvest
vegetation
- chemical requirements for chlorination and/or enhanced nutrient removal
- equipment as needed--pumps, chemical feeders, plant harvesting equipment
- management of accumulated solids materials within any wetland-wastewater
system, particularly if primary or untreated effluent is being applied.
- Mosquito control may be necessary. Fish that prey on mosquitoes and good
water circulation are methods to inhibit mosquito populations. A mat of
duckweed will prevent mosquito production in an aquaculture system as
long as the entire surface area of each pond is covered.
- Water losses as a result of hyacinth growth can be significant. Evapo-
transpiration rates have been reported to be approximately three to six
252
-------
6.1.6 Continued
times higher for waters covered with hyacinths than for open waters
(O'Brien 1981). Within Florida, water losses could be a particular
concern. Total dissolved solids build-ups can also result. Greenhouse
structures can reduce water losses and, at the same time, allow hyacinths
to grow year-round if water temperatures can be kept at favorable levels.
Costs for such greenhouse structures have not been reported in the litera-
ture.
For natural wetlands, an important operational consideration is to allow
the area to maintain its natural condition (Odum 1980):
- A wetland area should be allowed to maintain its self-organizing
patterns
- Artificial changes in water table levels and flow patterns should be
limited
- Artificial swamps and marshes can be created if the water seal, in-
flow-outflow patterns and nutrient regime can be adjusted. Diversity of
seeding is the safest principle for insuring that a wetlands ecosystem is
established quickly.
These concepts represent a different approach to those described for the
artificial system above. It should be noted that both approaches potentially
have merit depending on the natural system available for use, the size of
area available for development as a wastewater management system, and the
amount of wastewater to be discharged per unit area.
253
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.7 Costs and Economic Values
COSTS CAN BE FAVORABLE COMPARED TO MORE CONVENTIONAL
WASTEWATER TREATMENT PROCESSES
Several site-specific conditions can affect system costs.
In general, wetland wastewater systems are less costly
than more conventional processes (systems) because the
natural environment and naturally available energy are
utilized. The importance of considering all aspects of
costs including uncertain treatment reliability, is also
discussed.
Various pilot-scale and full-scale wetland systems have been shown to be
more cost-effective and energy efficient than comparable, conventional waste-
water treatment processes (Weber et al. 1981). Both capital costs for
facilities and operation-maintenance costs associated with labor and energy
needs have been lower.
Costs for natural wetland systems primarily result due to costs for
planning, design, implementation, operation and maintenance of:
- Pre-application treatment
- Piping and perhaps pumping wastewater from a treatment plant to a wetland
area
- Distributing wastewater to a wetland area
- Potential land costs
- Minor earthwork.
These costs should include costs for field work and monitoring as well as for
other aspects of wastewater management. More extensive containment struc-
tures and channels may be needed for artificial wetland systems which
increase total system costs. Costs can be kept low by: 1) not installing
many facilities within a wetland area, 2) not removing vegetation from a
wetland area on a continuing basis unless energy production or resource re-
covery from removing vegetation is cost-effective or if removal of vegetation
is a necessary part of treatment activities, 3) optimizing or minimizing
storage requirements, 4) optimizing chlorination and dechlon'nation
requirements, and 5) avoiding large land costs.
Very little costing information is available in the literature for
hyacinth-wastewater systems. A series of basins with associated weirs and
pumps is neither particularly sophisticated nor costly. Capital costs for
these facilities depend primarily upon hydraulic detention time and pond
depth. If untreated wastewater is input to the system, additional equipment
such as a bar screen, grit chamber and perhaps an additional basin is
254
-------
6.1.7 Continued
required. Aerators and greenhouse covers are optional equipment that could
enhance system performance.
Within any aquaculture system, biomass needs to be harvested periodically
if biomass production is to be kept as high as possible. Unfortunately,
biomass harvesting cannot, at the present time, pay for itself by utilizing
harvested biomass for animal feed, fertilizer, or energy production.
Harvesting and various other equipment is needed, including a front-end
loader, a truck and/or a wagon, and perhaps a mechanical chopper (for
hyacinths, depending upon how the harvested biomass is to be utilized).
Hyacinths can be composted and digested anaerobically to produce methane or
processed into animal feed. All of these processes have been shown feasible
but not competitive economically. Additional studies of converting hyacinths
to energy are needed to investigate more economically efficient conversion
methods and also to market the potential for the product.
Tchobanoglous and Gulp (1980) have prepared cost estimates for these
comparable wastewater treatment-disposal systems: 1) activated sludge (AS)
plus chlorination (C), 2) primary treatment (P) plus artificial wetlands (AW)
plus chlorination, and 3) facultative pond (FP) plus artificial wetlands.
Plant harvesting and energy production from plant biomass were not included
in the cost estimates. The third option included no sludge management or
dechlorination costs. No mention is made of provisions for back-up
facilities. The results of this cost estimate are shown in Table 6.1-7.
Facilities were sized to represent typical systems under average climate,
topography and wastewater conditions.
As shown, the second system-primary treatment plus artificial wetlands
plus chlonnation-is the least costly. The authors go on to state that even
with land costs of $10,000 per acre the second system is still less costly
than conventional, activated sludge treatment plus chlorination.
This analysis by Tchobanoglous and Gulp (1980) does imply, however, that
treatment efficiencies are similar for the three systems. Such similar treat-
ment efficiencies are not necessarily obtainable. Moreover, the costing
assumptions which were utilized could differ significantly on a site-specific
basis. r
No cost analyses have been found in the literature for the general use of
natural or artificial wetlands to provide more advanced forms of treatment,
such as nutrient removal. Such a cost analysis would need to include an even
larger number of assumptions than Tchobanoglous and Gulp had to utilize, many
of which could differ significantly at different locations. Therefore, costs
for wet!and-wastewater systems should be compared to costs for more conven-
tional forms of treatment only on a site-specific basis.
Fritz and Helle (1978) have developed a site-specific cost analysis for
an anticipated advanced treatment system in Waldo, Florida. Their analysis
does indicate that, for Waldo, Florida, advanced treatment utilizing cypress
of secondary 'e'"] „»".'* """ SffV irr19at1°" °r P^al-chemical treatment
255
-------
Table 6.1.7. Annual and Unit Costs,' Excluding Land, for Treatment Systems.
Item
Capital cost, $ x 10*
O&M cost, $/y
Labor, $10/p.h
Power, $0.06/KWH
Chlorine, $300/tor
Parts and supplies
Subtotal
Amortized capital
(8% at 20 y)
Total annual cost, $
Unit cost, $1000 gal
AS+c
Plant size,
0.1
0.71
16,000
10,400
457
8,000
34,857
72,313
107,170
2.94
0.5
1.23
36,000
27,940
2,283
12,000
78,223
125,275
203,498
1.12
mgd
1.0
1.60
55,000
41,556
4,566
16,000
117,122
126,960
280,082
0.76
P+AW+c
Plant size,
0.1
0.37
12,500
5,572
228
3.000
21,300
37,684
58,984
1.62
0.5
0.55
30,000
11,378
1,142
5,000
47,520
52,962
100,482
0.55
mgd
1.0
0.90
45,000
19,456
2,283
7,000
73,739
91,655
165,404
0.45
0.1
0.49
12,500
5,883
--
3,500
21,883
49,905
71,788
1.97
FP+AW
Plant size, mgd
0.5
1.12
30,000
11,494
--
4,500
45,990
114,072
160,062
0.88
1.0
1.80
45,000
18,600
—
6,500
70,100
183,330
253,430
0.69
*Land costs are excluded. Costs represent June 1979 prices.
AS+C: activated si jdge plus chlorination
P+AW+C: primary trea;ment plus artificial wetland plus chlorination
FP+AW: facultative oond plus artificial wetland
Source: Tchobanoglous and Gulp. 1980.
-------
6.1.7 Continued
Uemgen and Note (1980) have presented site-specific costs of an arti-
ficial wetland wastewater system for Mt. View Sanitary District in
California.
Crites (EPA 1979) has developed comparable cost estimates for convention-
al, advanced secondary treatment processes, land application, and hya-
cinth-wastewater systems managing 3,800 cubic meters per day (1 mgd) The
conclusion from this effort is that hyacinth-wastewater systems offer
low-cost, low-energy wastewater treatment options. For the given conditions
land application was found to be more costly than a hyacinth-wastewater sys-'
tern.
Cost-effectiveness must consider environmental impacts, system oper-
ability and system implementability as well as costs. Mitigative measures
such as actions to control mosquitoes, flies or odors, must also be included
In addition to mitigative measures, the use of wetland areas for wastewater'
management could alter local economic conditions. Wetlands can attract
investments to a local area according to Odum (1980), at least for locations
which he has considered. In contrast, management of wetlands could also
detract from investments under certain conditions. These effects should be
included in any cost effectiveness analysis for wetland-wastewater systems
257
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6.0 ENGINEERING CONSIDERATIONS
6.1 Facilities Planning/Preliminary Design
6.1.8 Areas of Uncertainty
SOME UNCERTAINTIES EXIST THAT COULD IMPACT DECISION MAKING
Variability of the natural environment (particularly
climate) from location to location, inability to
quantitatively predict biological reactions, a lack of
large amounts of experience with wetland-wastewater
systems, and the difficulty with monitoring ecological
stress are the primary uncertainties of applying waste-
water to wetland areas.
Wetlands discharges, from an engineering design viewpoint, pose a variety
of problems that differ from traditional treatment and discharge considera-
tions. Wetland types vary significantly in their ability to assimilate
wastewater, in dominant vegetation, size, and hydrologic characteristics, all
of which affect design criteria. A series of concerns unique to wetlands
need to be incorporated into engineering design, yet sufficient information
to establish criteria is limited. Some of these issues include:
- the inability to predict biological and ecological changes as functions
of temperature, water availability, wastewater characteristics, and other
variables (e.g., changes in species composition, odor production, mosqui-
to/fly breeding)
- a lack of long-term experience with wetland-wastewater systems that limit
estimates of long-term effects of wastewater applications (e.g.,
accumulation of substances within wetland areas, potential toxic effects,
or long-term changes in species composition and productivity)
limited information exists to evaluate changes in a regional water budget
if significant quantities of wastewater are diverted to wetland areas
- meteorological parameters are relatively unpredictable; water levels and
circulation patterns within a wetland area will be unpredictable as a
result
- limits concerning how much a wetland area can be disturbed by wastewater
management activities before intolerable consequences occur have not been
quantified.
Many of these uncertainties can, unfortunately, affect the entire perform-
ance of a wetland-wastewater system in significant and adverse ways. Ration-
al design criteria for wastewater-wetland systems may only be able to be de-
veloped as more systems are implemented. These systems are too complex to be
designed reliably based on mathematical equations and laboratory simulations.
Tchobanaglous and Culp (1979) contend that reliable, standard design
criteria cannot be developed even if hundreds of reliable natural wetland
wastewater systems are implemented. Variations in environmental character-
istics at different locations would force pilot-scale testing to be conducted
258
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6.1.8 Continued
at a site before a full-scale wetland-wastewater system could be implemented
and effectively operated. So many unknowns or uncertainties are related to
soils, vegetation, and other site characteristics that design, installation
and operation procedures must be tailored to individual wetland areas. This
does not necessarily detract from the use of wetlands for wastewater
disposal. It acknowledges that standard design criteria as developed for
conventional systems probably cannot be developed for wetlands systems.
However, guidelines and ranges of acceptability can be established for the
design of wetlands systems.
Fewer uncertainties and research needs are evident for hyacinth-waste-
water systems than for any other type of wetland-wastewater or
aquaculture-wastewater system. Yet even for hyacinth-wastewater systems,
more data are needed to establish: 1) preferred hyacinth harvesting and
utilization techniques (Middlebrooks 1980), 2) optimum harvesting strategies
that would vary for different locations, 3) alternataive methods to provide
improved phosphorus removal wherever such removal is needed (O'Brien 1980),
and 4) the best wastewater management methods to institute during periods
when hyacinths are unable to grow. For more northern locations within Region
IV of the EPA, efforts are needed to establish treatment efficiencies, costs
and operability of other aquatic plant-wastewater systems, such as duckweed
systems. In addition, the economics of converting harvested plant mass to
compost, energy or animal feed need to be periodically re-evaluated in light
of uncertain economic conditions at the present time. If new, less expensive
technology for converting plant mass to energy could be developed, aquatic
plant-wastewater systems could conceivably pay for themselves in the future.
259
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6.0 ENGINEERING CONSIDERATIONS
6,2 Design of Natural and Artificial Wetland-Wastewater Systems
TRADITIONAL DESIGN CRITERIA FOR WASTEWATER MANAGEMENT
SYSTEMS NOT AS APPLICABLE TO WETLANDS
Although numerous wetlands disposal sites currently exist
insufficient evaluations have been conducted to establish
design criteria for the variety of wetlands found in
Region IV. It is clear, however, what type of design
criteria should be developed.
As for any wastewater management system, a variety of tasks must be
undertaken to properly design the system. As indicated in the previous
section generic design criteria applicable to all wetlands is probably not
feasible. However, a range of criteria can be proposed based on evaluations
of existing wastewater systems: even then uncertainties remain. This
represents a major difference between traditional wastewater systems and
wetlands wastewater systems. Despite this limitation the range of values
observed for existing wetlands discharges will be related to design criteria.
Not unique to wetlands discharges but an area that requires unique
considerations is that of mixing and flow patterns. This relates directly to
the type of wastewater distribution system that might be most effective for a
particular wetland.
Site access and easements, safety factors, and specifications for
structures are elements of design of any wastewater management system yet
involve a different series of considerations for wetlands systems.
260
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6.0 ENGINEERING CONSIDERATIONS
6.2 Design of Natural and Artificial Wetland-Wastewater Systems
6.2.1 Design Criteria
GENERIC DESIGN CRITERIA FOR ALL WETLAND TYPES NOT FEASIBLE
Pilot studies may be required at natural wetlands to
determine proper loading rates and design criteria for
each wetland system. Some general criteria have been
suggested for artificial wetlands which may be applicable
to natural systems as well. Design criteria for water
hyacinth systems have been recommended.
The lack of established design criteria for natural and artificial wet-
lands is due, in part, to the relatively small number of operating systems
and the extent of long-term research conducted. However, this void is also a
function of the many site-specific components, such as climate, vegetation,
soils and natural flow patterns.
In the design of artificial wetland systems, some degree of control over
the site-specific components is possible. Tchobanoglous and Culp (1980)
developed the preliminary design parameters shown in Table 6.2.1-a and Crites
(1979) reports the following values used for artificial wetlands:
Parameter Reported Range
Detention Time, days 2 to 25
Depth, ft (m) 0.52 to 3
(0.2 to 0.9)
Area, Acres/mgd 10 to 130
(ha-day/m3) (0.0011 to 0.0139)
For natural wetland areas, detention times may be considerably longer
than for artificial wetlands. However, because such characteristics as flow
paths, extent of percolation, and nonpoint source imputs are so difficult to
quantify for a natural wetland, detention time as historically defined (vol-
ume/flow rate) becomes less meaningful as an engineering term. Land area
requirements typically range from 30 to 60 acres per million gallons of
wastewater, although larger areas may be required for significant removal of
nitrogen and phosphorous (Tchobanoglous 1980). Loading rates to artificial
(Table 6.1.5-c) and natural wetland systems which have been studied in Region
IV vary greatly:
location Pre-Treatment
Whitney Park, FL
Wildwood, FL
Reedy Creek, FL
Gainesville, FL
Jacksonville, FL
Secondary
Primary
Secondary
Package Plant
Secondary
0.026 (243)
0.214 (1,997)
0.0054 (50)
0.0168 (157)
0.094 (880)
261
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Table 6.2.1-a. Preliminary Design Parameters for Planning Artificial Wetland
Wastewater Treatment Systems3
ru
o^
ro
Characteristic/design parameter
Flow
Detention
Time, d
Type cf System Regime^ Range Typ.
Depth of
Flow, ft (m)
Range
j£Ri
Trench (with PF 6-15
reeds )r rushes)
Marsh 'reeds AF 8-20
rushes others)
Marsh-f'Ond
1. Marsh AF 4-12
10
10
1.0-1.5
(0.3-0.5)
0.5-2.0
(0.15-0.6)
1.3
(0.4)
0.75
0.25
0.5-2.0 0.75
(0.15-0.6) (0.25)
Loading rate
g/ftLd (cm/d)
Range
Typ.
0.8-2.0 1.0
(3.25-8.0) (4.0)
0.2-2.0 0.6
(0.8-8.0) (2.5)
0.3-3.8 1.0
(0.8-15.5) (4.0)
2. Pond
Lined trench
AF 6-12
PF 4-20
(hrs)
8 1.5-3.0 2.0
(0.5-1.0) (0.6)
6
(hr.)
0.9-2.0
(4.2-18.0)
5-15
(20-60)
1.8
(7.5)
12
(50)
aBased )n the application of primary or secondary effluent.
bPF = p ug flow, AF = arbitrary flow (partial mixing).
Source: Tchobanoglous and Gulp. 1980.
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6.2.1 Continued
Loading rates for natural wetlands will be greatly influenced by the
hydrology of the system (see Sections 4.3 through 4.3.5). If nutrient
(nitrogen and phosphorus) removal is an objective of a natural wetland-waste-
water system, nutrient cycling and transformations within the wetland area
must be also investigated (see Sections 4.4.4 through 4.4.4.2).
Aquaculture systems generally consist of one or more basins or ponds
inhabited by one or several species of aquatic plants or animals. Selection
of plant/animal species is based on several factors (Bowker 1982):
degree of pre-treatment
required treatment level
by-product recovery
requirements of plant/animal species.
Preferred plant species for aquatic systems have the following charac-
teristics (Bowker 1982):
rapid growth rate in waste-enriched waters
high nutrient and mineral absorption capability
harvesting ease (floating plants)
good nutritive value or value for energy production
not susceptible to minor environmental changes
disease resistant.
Water hyacinths have been the most commonly used plant for aquatic
systems in the past. This species thrives in waters with municipal effluent;
it also appears to do well in mixtures of municipal and industrial waste-
water. The use of water hyacinths is limited, however, by the fact that
growth ceases at temperatures below 10°C (50°F). Duckweed, another species
which has been used in aquatic systems, has a much wider geographic range
because it vegetates above 1-3°C (33.8-37.4°F), and it winters well (O'Brien
1981).
Several sets of design criteria have been noted in the literature. These
criteria are essentially similar; discrepancies result from differences in
influent quality and treatment objectives. Middlebrooks (1980) suggests that
hydraulic loadings to a water hyacinth system of 1) 2,000 m3/ha-day (214,000
gal/acre-day) of secondary effluent and 2) 200 m3/ha-day (21,400
gal/acre-day) of untreated wastewater "appear reasonable" if nutrient control
is not an objective. These values are consistent with those given by O'Brien
(1981) for raw wastewater systems (Table 6.2.1-b) and by the Texas Department
of Health (Table 6.2.1-c) for secondary effluent systems without nutrient
control.
Broad, rectangular basins with a length to width ratio of 3 to 1 are
recommended for aquatic plant systems to provide suitable hydraulic
characteristics (EPA 1982). Water hyacinth basins should have an area less
thari or equal to 0.4 ha (1 acre) based on ease of harvesting and cleaning. A
long rectangular basin may have an area greater than 0.4 ha (1 acre)
(Middlebrooks 1980).
263
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6.2.1 Continued
To produce an effluent with 2 mg/1 of TN, Middlebrooks (1980) suggests
less than 0.4 meter (1.3 ft) pond depth and an approximate loading rate of
500 m3/ha-day (53,500 gal/acre-day) of stabilization pond effluent. These
criteria are intended to provide maximum contact of wastewater with the root
system. In addition, regular harvesting should be conducted to remove
nutrients from the system. As shown in Table 7.2.4, O'Brien gives a depth of
0.91 meter (3 ft) and a loading rate of 800 m3/ha-day (85,500 gal/acre-day)
to provide an effluent with less than or equal to 5 mg/1 TN.
As the harvesting of hyacinths disrupts treatment, Dinges (EPA 1979)
recommends draining each basin annually and removing accumulated sludge and
plant debris. Harvested hyacinths should be dried prior to ultimate
disposal. This can be accomplished on sloped, impervious areas; the water
released as the plants decompose can be drained to a soil absorption system.
Dried plants can be plowed or disked into adjacent farmland, composted, made
into animal feed or converted to biogas through anaerobic digestion (O'Brien
1981).
There appears to be sufficient data for the design of water hyacinth
aquatic systems. Although much of the design of other types of plant aquatic
systems may be similar, several critical parameters, particularly the loading
rate and detention time, will vary with different plant characteristics.
Scant data are available on which to base design criteria for animal or
integrated systems. More research is needed before standards can be
developed for this technology.
264
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Table 6.2.1-b Design Criteria for Water Hyacinth-Wastewater Treatment Systems
to be Operated in Warm Climates (based upon best available data).
Parameter
A. RAW WASTEWATER SYSTEM
(Algae Control)
Hydraulic Residence Time
Hydraulic Loading Rate
Depth, Maximum
Area of Individual Basins
Organic Loading Rate
Length to Width Ratio
Hyacinth Basin
Water Temperature
Mosquito Control
Diffuser at Inlet
Dual Systems, Each
Designed to Treat
Total Flow
B. SECONDARY EFFLUENT
SYSTEM
(Nitrogen Removal and
Algae Control)
Hydraulic Residence Time
Hydraulic Loading Rate
Depth, Maximum
Area of Individual Basins
Organic Loading Rate
Length to Width Ratio of
Hyacinth Basin
Mosquito Control
Diffuser at Inlet
Dual Systems, Each
Designed to Treat
Total Flow
Nitrogen Loading Rate
Design
Metric
> 50 days
200 m3/ha-day
< 1.5 meters
0.4 hectare
j< 30 kg BOD5/
ha. day
>3:1
>10°C
Essential
Essential
Essential
> 6 days
800 m3/ha-day
0.91 meter
0.4 hectare
_< 50 kg BOD5/
ha-day
> 20°C
Essential
Essential
Essential
j< 15 kg TKN/
ha-day
Value
English
> 50 days
0.0214 mgd
_< 5 feet
1 acre
< 26.7 Ibs
BOD5/ac.day
>3:1
>50°F
Essential
Essential
Essential
> 6 days
0.0855 mgd
3 feet
1 acre
< 44.5 Ibs
BOD5/ac'day
> 68°F
Essential
Essential
Essential
< 13.4 Ibs
TKN/ac-day
Expected
Effluent
Quality
BOD5 _< 30 mg/1
SS _< 30 mg/1
BOD 5 _< 10 mg/1
SS <. 10 mg/1
TP _< 5 mg/1
TN _< 5 mg/1
Source: O'Brien 1981, and Middlebrooks 1979.
265
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Table 6,2.1-c Recommendations for the Construction of Hyacinth Basins for
Upgrading Stabilization Pond Effluent.
Parameter
Loading rate
Basin length to width ratio
Basin construction
-Side slopes
-Freeboard
-Width
Minimum
Basin piping
(diameter)
Design
Metric
2000 m3/ha-day
3:1
1:3
0.61 m
3.0 m
0.25 m
Value
English
0.2 mgd/acre
3:1
1:3
2 ft
10 ft
10 inches
Additional specifications:
Dual systems, each capable of treating average daily flow
Barrier provided by 1 percent of total area in clear area around the
Outlet
* Mosquito control provided by 8 to 10 ft. diameter fish enclosures spread
throughout the basins.
Man-proof fencing surrounding system
Water level gage to provide depth control
Source: Dinges. 1976.
266
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6.0 ENGINEERING CONSIDERATIONS
6.2 Design of Natural and Artificial Wetland-Wastewater Systems
6.2.2 Wetland Mixing Patterns and Methods of Effluent Application
WETLAND MIXING AND FLOW PATTERNS INFLUENCE APPLICATION METHOD
Selection of application method is site-specific. Mixing
and flow patterns can be controlled.
The source, velocity and application rate of wastewater into a wetland
directly control the spatial heterogeneity of flows in wetlands and the
nutrient, oxygen, and toxin load of sediments. These secondary factors in
turn control or modify such ecosystem characteristics as species composition,
primary productivity, organic deposition and flux, and nutrient cycles
(Gooselink 1978).
Numerous methods of effluent application can be employed. A single dis-
charge from the point at which a stream enters a wetland, at the edge of a
wetland, or at a location within the interior of a wetland is possible. A
discharge can also be distributed uniformly across a lateral section, perpen-
dicular to the general direction of flow. Such a multi-point discharge
provides greater initial mixing with the receiving water and smaller area
loadings. As compared to a single-point discharge, however, the multipoint
discharge would have greater construction impacts, be more difficult to
operate and maintain, and would be more expensive (particularly if a number
of unrelated disposal locations are utilized). Based on site visits con-
ducted during this EIS the following observations were made:
- wastewater treatment plant owners will utilize the least costly effluent
disposal system (point discharge to edge of wetland) unless required to
do otherwise
- installing pipe in any manner other than laying it on the ground surface
will require temporary drainage, excavation, and backfill
- continuous flows of wastewater from a pipe or channel will create
channelized flow for at least a few hundred feet into the wetland area.
The location and type of effluent application for a given wetland area
should be selected based on the following factors:
- path and direction of flow
- type, arrangement, and density of vegetation
- potential for mixing with receiving waters.
The choice of discharge configurations is important if a specific level
of treatment is desired and is imperative to maintaining the environmental
values and functions of a natural wetland. At higher application rates
configurations which provide distribution within the wetland are more
attractive because 1) adequate distribution is needed to achieve desired
treatment, and 2) erosion and channelization impacts from point discharges
267
-------
CD
Table 6.2.2. Efflti;nt Application Configurations.1
Advantages
Effluent Applicatio
Configurations
Disadvantages
Comments
Point discharge at '!dge
of wetland, gravity flow
Channel discharge
edge of wetland,
gravity flow
Distribution within
wetland, gravity flcv
Distribution within
wetland, spray flow
Low cost
Low O&M requirements
Low energy use
Can be installed with minimal
impacts to a natural wetland
Low O&M requi rements
Installation impacts limited
to edge of wetland
May provide some dechlorination
within channel (cascade affect)
More uniform distribution
Relatively low (&M requirements
(no moving parts)
- Distribution of wastewater
- May provide some dechlorination
- Low erosion potential
via spraying
Often poor or unknown distri-
bution of wastewater
Erosion and channelization may
occur if wastewater velocity
is high
Solids may accumulate near
Distribution may be improved by selection
of discharge point to take advantage of
natural flow paths, increasing the number
of discharge points, or enhancing mixing
within the wetland by mechanical or
__..__ ...__, __^ .,„„. physical devices
discharge if wastewater velocity - Erosion control techniques are available.
is low
Often poor or unknown distribu- - Concrete or grass-lined channel may be used
bution of wastewater - Erosion control techniques are available
Erosion or channelization may
occur if wastewater velocity is
high
Solids may accumulate near
discharge if wastewater velocity
is low
Installation impacts to
natural wetands
Installation costs
Aerosols may cause public health
impacts
Energy required
Nozzles may clog unless pre-
treatment includes fine
screening
O&M requirements higher than
for other alternatives
Installation impacts to natural
wetlands
Installation costs
Distribution may be accomplished by pipe
outfalls at a variety of points within
wetland, or by perforated or gated pipes
Pipes can be installed on the surface,
buried or elevated
Surface pipes will have lesser installation
impacts and costs but will have greater O&M
requi rements
Piping may be laid on the surface,
buried or elevated
Surface piping will have lesser installation
impacts and costs but will have greater
O&M requi rements
1. U.S. EPA. Assesjiient of current information on overland flow treatment of municipal wastewater. May 1980, p. 63.
Source: Gannett Fleiring Corddry and Carpenter, Inc.
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6.2.2 Continued
can become significant if not properly controlled.
To further enhance mixing in a wetland area, wind-driven circulators or
aerators can be used. Flow paths in artificial systems can be controlled by
structures (wiers, dikes, baffles, etc.), vegetation, or levees.
Many methods are available; few have been utilized, particularly for
natural systems. Least-cost discharges to the edge of wetlands nearest waste-
water treatment plants have most often been utilized within Region IV.
269
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6.0 ENGINEERING CONSIDERATIONS
6.2 Design of Natural and Artificial Wetland-Wastewater Systems
6.2.3 Site Access and Easements
THE GOAL IS OFTEN TO PROVIDE ACCESS TO OPERATORS AND TO
PREVENT ACCESS BY THE PUBLIC
Inlet/outlet location and multiple plots can provide
greater operator access for natural and artificial systems
respectively. Fencing and buffer zones can discourage
public access.
A wetland-wastewater system should be designed to provide easy access for
operation and maintenance while at the same time controlling public contact
with the system.
For a natural wetland area, inlet and outlet structures should be located
to provide easy access with the least possible removal of natural vegetation.
Site access can be made easier in an artificial wetland by providing multiple
plots divided by levees large enough for vehicular traffic. Multiple plots
also provide greater control of erosion and vectors.
Most wetland-wastewater system should have a fence or posting around its
periphery if public access is to be prevented. Additionally, a buffer zone
surrounding the system should be provided. No information was found in the
literature regarding the size of such a buffer zone. A 200-foot buffer is
generally provided for spray irrigation land application systems. A similar
figure may also be appropriate for use with wetland systems.
270
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6,0 ENGINEERING CONSIDERATIONS
6.2 Design of Natural and Artificial Wetland-WastewaterSystems
6.2.4 Safety Factors to Account for Uncertainties
SAFETY FACTORS ARE IMPORTANT FOR WETLAND DISPOSAL SYSTEMS
DUE TO THEIR FUNCTION AND COMPLEXITY AS ECOSYSTEMS
Given the uncertainties associated with the design of
wetland systems safety factors must be incorporated.
These include buffer zones, storage facilities, and
monitoring of wetlands.
Given the small number of operating wetland-wastewater systems and the
limited knowledge regarding removal/conversion mechanisms and rates, it will
be desirable to incorporate certain safety factors into the design of the
system. Such factors could include the following:
- storage facilities to provide for excessively wet periods, cold periods
(if nutrient and metal uptake are significant and desired in the system),
and, possibly, dechlorination
- nutrient removal in pre-treatment
- buffer zone
- system isolation
- chlorination perhaps followed by dechlorination
- monitoring of system discharge and receiving waters (surface and ground-
water)
- monitoring of vegetation for:
1. metal or toxin accumulation
2. changes in natural vegetation
harvesting of vegetation.
These measures can help assure that a wetland system is not overloaded,
that wastewater is properly assimilated, and that wetland functions are
maintained.
271
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6.0 ENGINEERING CONSIDERATIONS
6.2 Design of Natural and Artificial Wetland-Wastewater Systems
6.2.5 Drafting and Specifications
GUIDELINES FOR DRAFTING AND SPECIFICATIONS OF STRUCTURES AND EQUIPMENT
ARE NOT ESTABLISHED
A representative list of items that require specification
Includes pipe sizes, influent structures, and flow path
controls.
Because of the small number of wetland-wastewater systems in operation,
no guidelines on drafting and specifications have been established. General-
ly speaking, however, the following list is representative (but not all in-
clusive) of the type of items that will require specification to the
contractor:
- pipe depths, sizes, and types for transmission of wastewater to a wetland
and the distribution system
- influent structures such as 1) stand pipes, wiers, or gate valves for
artificial wetlands or cypress domes or 2) irrigation pipes (aluminum)
with multiple flap gates
- plastic or clay liner to prevent percolation to water table for
artificial wetlands, if desired
- artificial substrates used to enhance or replace vegetation in artificial
wetlands
- structures or mechanical devices to control flow paths or mixing
patterns, such as
1. vegetation
2. levees
3. wind driven circulators or aerators
- filter around effluent structure of aquaculture system to prevent the
escape of plants
- circular galvanized wire mesh enclosures in ponds to improve production
of fish used for controlling mosquitos
- installation equipment and methods to minimize construction impacts.
Any operation and maintenance procedures that could directly affect the
performance of structural facilities can be incorporated into design
specifications or within an operation and maintenance bulletin or manual.
272
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6.0 ENGINEERING CONSIDERATIONS
6.3 Installation of Wetland-Wastewater Systems
INSTALLATION AND CONSTRUCTION TECHNIQUES ARE IMPORTANT
TO MAINTENANCE OF WETLAND
Overly expedient or careless installation procedures can
cause operating problems as well as damage to natural
wetland areas. Techniques to both minimize disturbances
and enhance distribution of effluent throughout a wetland
area are presented.
Excellent planning, design, operation and maintenance will not ensure
satisfactory wastewater treatment results from a wetlands area if installa-
tion causes irreparable damage to the wetland system.
Little information exists in the literature pertaining to installing a
wetland-wastewater system. Many of the concepts presented in this section
are based on experience with installing other types of wastewater systems.
Other types of construction experience in wetlands (highways, etc.) may be
helpful in avoiding the difficulties presented in the construction of waste-
water facilities. The lack of experience with installing wetland-wastewater
systems should, at a minimum, force engineering contractors to be more
careful and conservative in their activites.
Installation as it pertains to artificial wetland systems and aquaculture
systems involves creating a wetland area where previously such an area did
not exist. Installation in a natural area involves constructing the means of
applying wastewater to the existing area. Installation within natural
wetlands either attempts to simply transport wastewater to the wetland or to
circulate wastewater to the desired locations. Associated pumping stations
and treatment facilities may also be required.
273
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6.0 ENGINEERING CONSIDERATIONS
6.3 Installation of Wetland-Wastewater Systems
6.3.1 Installation Techniques
INSTALLATION TECHNIQUES THAT MINIMIZE ADVERSE IMPACTS ARE DESIRED
Natural wetland areas and artificial wetland areas require
different installation techniques. Possible techniques to
minimize adverse impacts include berms and boardwalks.
The major factor affecting the selection of installation techniques is
the type of wetland in question. To inhibit adverse environmental impacts
natural wetlands should be as undisturbed as possible when being incorporated
into a wastewater treatment scheme. This lack of disturbance limits installa-
tion flexibility. Artificial wetlands, by definition, require significantly
more construction activity, which allows for greater flexibility in installa-
tion alternatives. Some of the methods utilized to minimize disturbance from
installing wastewater application systems in natural wetlands are listed
below (EPA 1981):
- planks laid on peatland to permit laying of pipe and movement of people
(Drummond, WI)
- walkway suspended above a peatland surface (Houghton Lake, MI)
- berm and pathway lined with gravel into a forested wetland (Bellaire, MI)
- a point discharge ditch at the periphery of a wetland (Kincheloe, MI).
No study has been done to determine the relative merits of these or other
methods (EPA 1981).
Installation techniques for natural wetlands are necessarily dictated by
the physical characteristics of the wetland area such as:
- type of wetland (e.g., peat bog versus reed meadow)
soil depth to stable material
- erodability of wetland material
- water velocities and circulation patterns
- ecological sensitivity of the wetland system.
Although the desire to minimize wetland disturbances is a primary
objective in the installation of artificial systems, the greatest concern is
stabilizing areas disturbed by required construction activity. In some
cases, actual construction activity may be significant, while for other
cases, minimal activity may be required. Installation techniques will
generally be dictated by such factors as: costs, system size, equipment
availability, site configuration and contractor experience.
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6.3.1 Continued
Supplemental installation activities such as the following can be
instituted, particularly for natural wetlands:
- minimize all slopes to reduce erosion potential
- avoid soil compaction where not required
- revegetation will require water-tolerant species
- all levees should be at least ten feet wide and one foot above the
highest water level for access ease (ASCE 1978)
- maintain strict control of water entering and leaving the site during
installation to avoid unnecessary soil erosion and inhibition of installa-
tion activities
- avoid installing pipelines or facilities directly adjacent to a wetland
during ecologically-sensitive periods (e.g., during reproductive periods
for sensitive wetland species).
Improper installation can result in failure of the wetland system to
perform as envisioned. Artificial and aquaculture systems may not have
sufficient detention time if water flow to the system is not controlled.
Flow patterns within natural wetlands may be altered by installation of
distribution pipes. Modified water depths resulting from improper instal-
lation activities can also have detrimental impacts on naturally occurring
plant species. Natural wetland materials can be eroded if wastewater is
applied too heavily. Therefore, proper inspection of installation techniques
and materials is an important component of installation. Additional infor-
mation that could be useful in the installation of various types of equipment
in wetland environments may be available through pipe line contractors who
have worked under such conditions.
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6.0 ENGINEERING CONSIDERATIONS
6.3 Installation of Wetland-Wastewater Systems
6.3.2 Construction Inspection
INSPECTION OF INSTALLATION TECHNIQUES AND MATERIALS IS NEEDED
DURING CONSTRUCTION
Improper installation techniques and materials can cause
adverse environmental impacts. Inspection activities
should assure minimal disturbance to wetlands areas.
The objective of construction inspection is to ensure that all components
of the wetland system will function as intended after installation is com-
pleted. Because wetland areas may be significantly damaged by system
installation, proper inspection becomes very important.
The primary item of concern with inspection of wetland-wastewater system
construction is protection of the wetland area. Of particular concern for
both natural and artificial wetland areas are:
- maintenance of wetland vegetation and animal populations
- minimal disturbance of wetland soils and runoff patterns
- contamination of a wetland by construction material
- minimizing fuel and lubricant spillage
- controlling access to actual locations of construction.
Construction inspection for artificial wetland systems including aqua-
culture systems has many of the same concerns as for natural wetlands.
However, there are some factors that are unique to natural wetlands so that
additional effort should be used to ensure proper compliance. The factors of
major concern are as follows:
- control of water depths and the size of the area to be receiving
wastewater
- limited access to the wetland area
effective erosion control
Inspection activities need to focus on three areas: 1) site development,
2) materials, and 3) construction. Site development and construction have
been previously discussed. The materials used in wetland installation should
be compatible with site conditions; they must be able to withstand prolonged
wetness. Materials need to be able to function year-round for extended
periods of time to avoid excessive maintenance costs.
The primary benefits of inspection activity for wetland systems is the
added insurance that the system will function as intended. Additional costs
276
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6.3.2 Continued
incurred with detailed inspection should be considered as an inherent instal-
lation expense. The complexities and uncertainties of wetland areas make
detailed inspection an integral part of installation procedures.
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6.0 ENGINEERING CONSIDERATIONS
6.3 Installation
6.3.3 Operational Initiation
IMPROPER INITIATION PROCEDURES CAN DAMAGE WETLAND AREAS
Initiation procedures may differ between natural and
artificial systems. Season of the year and site are among
the factors influencing selection of initiation
procedures.
Initiation for wastewater applications to natural wetlands differs con-
siderably from that for artificial wetlands. Natural systems have existing
vegetation present to assimilate wastewater consitutents. Artificial systems
need to establish stands of plants sufficient to treat wastewater
effectively. The process of establishing wetland vegetation could take 6 to
12 months (Tchobanoglous and Gulp 1980). Within more southern areas of the
country, growths could develop more quickly.
Water hyacinths are well known for their ability to cover a wetland area
quickly and completely. Large aquaculture systems may require a mechanical
approach to harvesting such as that used at Walt Disney World, Florida
(Kruzic 1979). Because hyacinths normally begin to grow and multiply during
the spring, system start-up at that time would be appropriate and perhaps
more successful than during seasons when plant growth is inhibited. Duck-
weed, other aquatic plants or animal-based aquaculture systems would require
more care and time to begin operations effectively (Stowell et al. 1980). A
specialist knowledgeable in such aquatic systems may be needed.
Natural wetland system initiation is critical; an artificial system can
be re-seeded if the original vegetation does not survive. A natural system,
however, may be damaged by initiation procedures that Overload the immediate
capacity of the wetland. The degree of damage is site-specific. Damage
itself can be either organic or hydraulic in nature. Initiation of aquatic
systems needs to take the following concerns into consideration:
- season of the year
water levels
- ambient temperatures
- wastewater temperatures
- condition of wetland due to other environmental disturbances.
Specific initiation procedures need to be determined based on the wetland
site characteristics and the wetland1s ability to assimilate projected waste-
water loads. Procedures used for conventional land treatment systems may be
a useful source of ideas. The following list suggests some ideas that should
be considered to begin effective operation of wetland systems:
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6.3.3 Continued
- apply wastewater gradually
l
- begin when the wetland is at its most productive stage
- apply water when the greatest dilution exists but when hydraulic
overloads will not occur
- maintain suitable water levels
- ensure the wetland is not stressed for DO when wastewater is applied.
Within three northern artificial wetlands, aquatic plant communities were
established with relative ease, and efficient wastewater renovation was
accomplished (EPA 1981). For these three artificial wetlands, the installa-
tion process was monitored sufficiently to assess its success. Such
monitoring of wetland water levels, flow patterns, and vegetation growth can
help to determine if and when installation procedures can be modified or
halted on a temporary basis.
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6.0 ENGINEERING CONSIDERATIONS
6.4 Operation and Maintenance (O&M)
PROPER O&M IS ESSENTIAL TO SATISFACTORY PERFORMANCE
Present knowledge of effects of O&M techniques is limited.
O&M will be dependent on the primary objective of the
system.
Even if a wetland-wastewater system has been well-planned, well-designed
and well-installed, the system can still fail without proper and well-ex-
ecuted operation and maintenance. Although natural wetlands are more
environmentally significant, the artificial wetland and, particularly, aqua-
culture systems require more intensive O&M because wastewater loadings per
hectare (acre) are generally higher for artificial systems.
O&M decisions are dependent upon the primary objective of the system.
Some examples of primary objectives are the following:
- Maximize the level of treatment obtained within the wetland
- Minimize odor production, excessive erosion, and/or sludge accumulation
- Minimize adverse environmental impacts to the wetland
- Maximize the wildlife values of the wetland
- Maximize the amount of effluent released to the wetland
- Maximize biomass production.
Some wetland-wastewater systems may also be operated and maintained with
research as an objective. Once the primary objective is established (and
approved by the appropriate environmental agency if necessary), O&M pro-
cedures can be more clearly defined. O&M activities at operating wetland
systems visited by members of the project team were generally minimal. Costs
and a lack of established O&M procedures were noted as contributing factors.
The desire is to keep costs at a minimum.
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6.0 ENGINEERING CONSIDERATIONS
6.4 Operation and Maintenance (O&M)
6.4.1 Maintenance of Effluent Distribution Patterns
FLOW PATHS AND DISTRIBUTION PATTERNS CAN BE CONTROLLED
AS PART OF SYSTEM OPERATION
Methods and purposes of controlling flow paths and
distribution patterns are important to functions of
wetland systems. Periodic inspection of facilities and
management structures are important to operation.
Techniques for controlling flow paths and distribution patterns include
the following:
- Provide and maintain channels
- Provide mechanical or wind-driven aerators/circulation devices, or simple
baffles
- Manage the types and densities of vegetation within the wetland
- Control inflows and/or outflows by utilizing weirs, levees, and storage
ponds.
The use of storage ponds is discussed in Section 6.4.3.
Structures would require inspection and periodic maintenance. Mechanical
aerators would require electrical energy and connection to a source of such
energy. Managing vegetation types and densities may require .plant harvesting
equipment and plant seeding materials, as well as a person knowledgeable of
the impacts of such activities on the wetland. Inflows and/or outflows can
be controlled by designing and maintaining: 1) adjustable weirs whenever
water is released from a wetland to downstream areas, 2) levees or berms to
control the extent of wetland inundation, and/or, 3) storage ponds with
adjustable outlet weirs, outlet pipes with valves or pumping capability.
Alternate flow patterns could be established through a wetland by placing
channels, levees and weirs in specific configurations. Use of more than one
configuration within one wetland system provides operational flexibility in
case treatment efficiences are not as high, environmental impacts are unac-
ceptably adverse, or some other primary objective is not being met. However,
operational flexibility carries with it additional O&M efforts.
Additional efforts which would affect effluent distribution patterns
within a wetland are:
- The possibility of periodically flushing a wetland system (Tchobanoglous
and Culp 1980) to remove soluble compounds or to remove solid particles
with adsorbed nutrients
- Purposely encouraging or inhibiting vertical percolation beneath the soil
surface
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6.4.1 Continued
- Periodic harvesting of vegetation
- Purposely flooding a wetland system, perhaps during a particular portion
of the year, to promote anoxic conditions in the underlying soil.
Denitrification, which results in the release of nitrogen gas, can occur
only under anoxic conditions if an organic (carbon and combined hydrogen)
source is available. Water levels would need to be varied as well (Sloey
et al. 1978).
Vertical percolation can be encouraged by artifically draining adjacent
lands, providing underdrains, or by removing clay soils from a wetland.
Percolation can be inhibited by adding clay soils or an artificial layers, or
by allowing sludge from a wastewater treatment plant to be distributed
throughout all or part of a wetland.
For the objective of removing nutrients, as well as affecting flow pat-
terns, vegetation should be harvested several times during the growing
season. However, such harvesting can destroy aquatic habitat and, at the
same time, remove only 5 to 20 percent of the nutrients detained within a wet-
land system (Sloey et al. 1978). Further, multiple harvests have been
observed to reduce production and in some cases lead to plant succession
(Sanville 1983).
Water hyacinths must be harvested to obtain effective removal of nutri-
ents and BOD from wastewater. Such harvesting may need to be done every four
to six weeks during growing seasons (EPA 1977 and O'Brien 1980). Approxi-
mately 15 to 20 percent of the hyacinth plants can be harvested at one time
to produce optimum results (Coral Springs, Florida, system in EPA 1982).
Harvesting must be planned to avoid significantly decreasing the detention
time of wastewater within the hyacinth system.
Harvesting procedures have been estimated to require six to seven hours
of time for every 0.1 hectare (0.25 acre) to be harvested. Hyacinth biomass
can be composted after two to three weeks of drying. The biomass could also
be anaerobically digested to produce energy, or, as in Lakeland, Florida, the
biomass can be chopped, pressed and dried as part of a system to produce
pelletized animal feed (USEPA 1982). Duckweed harvesting is somewhat easier
than hyacinth harvesting.
Duckweed can be harvested by utilizing one of a variety of skimmer
devices developed originally for conventional wastewater treatment plants and
oil recovery systems. Duckweed could also be transported by pipe. Stored
quantities of duckweed can remain unspoiled for periods of weeks without
being treated (Hi 11 man and Culley 1978). Costs for precise harvesting or
processing methods for duckweed or for any other aquatic plants, except water
hyacinths, have not been developed.
According to Ryther et al. (Clark and Clark 1979) a hyacinth harvest
yield of 88 dry metric tons per hectare per year is considered to be close to
the maximum yield obtainable within the continental United States. These
authors assumed the hyacinths have an energy content of 20 million BTU per
dry ton, half of which would be recoverable via anaerobic digestion. Such
282
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6.4.1 Continued
estimates provide a preliminary basis for anticipating the amount of energy
which can be produced from harvested hyacinths.
Harvested yields of duckweed and hydrilla are 14 and 15 dry metric tons
per hectare per year compared to 88 dry metric tons of hyacinths per hectare
per year (Ryther et al. 1979).
Frequent harvesting of rooted aquatic plants is not recommended, because
plant stems are harvested while roots remain in the substrate. These roots
will extend more significantly if the stems are harvested frequently, thereby
contributing to system clogging (Pope 1981).
The optimal method for controlling flow patterns is largely dependent
upon both the system's primary objective and upon site-specific charac-
teristics and uncertainites. Possible operational policies towards flow
paths and effluent distribution include:
- Total "hands-off"
- Avoid inundation of vegetation or excessive erosion only
- Modify or avoid discharges when effluent or wetland displays certain
characteristics, such as poor effluent quality, large runoff flows from
upstream or noticeable adverse impacts of the wetland community
- Divert runoff flows from upstream areas away from the wetland system
- Manipulate flows into, around and out of the wetland system to accomplish
whatever objectives are primarily desired. Daily, weekly, and/or
seasonal procedures can be developed.
- Manipulate flows to promote revegetation or other natural reproduction,
wildlife.
Based on the extent of current understanding, pilot-scale testing of
possible techniques might be beneficial before affecting a large portion of a
wetland system with various artificially operated patterns of effluent
distribution. Distribution system alternatives will be dependent largely on
the type of wetland used for a discharge.
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6.0 ENGINEERING CONSIDERATIONS
6.4 Operation and Maintenance
6.4.2 Resting Periods and Use of Storage Facilities
RESTING PERIODS MAY BE BENEFICIAL FOR SOME WETLAND SYSTEMS
Resting periods may be used to recover wastewater treat-
ment capacity or to enhance environmental quality.
Storage facilities can provide the means to regulate water
depths, detention time, and wastewater inflows to wetland
areas.
Flows and water depths within a wetland system need to be maintained if
wastewater renovation is a primary objective. Denitrification is often
encouraged with greater water depths; the release of nutrients and toxic
compounds can be regulated by adjusting water depths (Tchobanoglous and Culp
1980), and detention time can be regulated by water depth and flow. Storage
facilities and control of discharges from wetlands to downstream areas can
allow wastewater flow and water depths within a wetland system to be
regulated.
A wetland system may require a resting period in order to: 1) recover
its capacity to renovate wastewater effluent, or 2) to enhance or maintain
important wetland functions. During a resting period, the treatment capacity
can be enhanced by 1) doing nothing, 2) passing water with silt through the
system to restore absorption capacity, or 3) passing nutrient-rich water
through the system to enhance growth. Bypasses of wastewater to other areas
should only be utilized when the impacts of that discharge on the downstream
areas receiving the discharge are judged to be acceptable.
Inoperability of aquaculture systems during winter months is a signifi-
cant concern. Hyacinths and other aquatic plants do not grow significantly,
even in central and southern Florida, between November and February. Since a
high level of wastewater flows may continue during these months, the waste-
water will need to be stored or treated in some other manner, or a tropical
climate will need to be artificially established through the use of
greenhouse covers.
Storage facilities and/or bypasses can also be utilized to maintain rela-
tively constant inflows to wetland systems. The natural environment is often
susceptible to adverse consequences if large flows of water or toxic com-
pounds are allowed to reach it. Difficulties and uncertainties about how
large to design storage facilities and bypasses and about when to utilize and
not utilize the facilities will be evident. The aspect of O&M associated
with resting periods and use of storage facilities/bypasses is, therefore,
best accomplished by experienced, innovative operators.
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6.0 ENGINEERING CONSIDERATIONS
6.4 Operation and Maintenance
6.4.3 Energy, Chemical and O&M Equipment Needs
ENERGY AND CHEMICAL REQUIREMENTS MINIMAL
For most wetland systems, energy and chemical requirements
are low. O&M equipment needs can be Important, but are
not extensive. O&M equipment can be major uses of energy.
Energy requirements vary for different systems because of site-specific
topographic characteristics. Wetland wastewater systems generally utilize
less energy than conventional advanced treatment processes and some land
application systems, because wastewater only needs to be distributed in the
wetland. Energy is often required for pumping wastewater or, if needed, for
providing disinfection, mechanical aeration, or harvesting of vegetation.
Chemicals to be utilized, if any, could include alum, ferric chloride, or
a polymer to enhance phosphorus removal and chlorine dioxide, other halogenat-
ed compounds, or ozone for disinfection. Lower amounts of disinfectant may
be needed for discharges to a wetland than for discharges to a stream, river
or lake.
Supplemental quantities of nitrogen could also be added to a wetland
system in order to increase vegetation production and thereby improve
phosphorus removal from wastewater. Iron salts can be added to prevent
buildups of chloride compounds (O'Brien 1980).
Equipment needs for O&M include pumps, replacement pipe and pipe support
structures, access vehicles (if needed) and vegetation removal equipment.
None of these forms of equipment are particularly difficult to obtain.
Harvesting equipment for aquaculture systems can include (EPA 1982):
- a "weed-bucket equipped, truck-mounted guideline" (Coral Springs,
Florida)
- a front-end loader, double-belt conveyor and chopper, and a forage wagon
(Lake Buena Vista, Disney World, Florida).
For natural and artificial wetlands, vegetation removal techniques can
include manual removal of vegetation from small areas or the use of a backhoe
or loader to scoop vegetation from the sides of channels. Control of algal
blooms, which limit BOD and suspended solids removal, can be provided by
zooplankton that utilize algae and organic detritus material as food sources
(ASCE 1978).
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6.0 ENGINEERING CONSIDERATIONS
6.4 Operation and Maintenance
6.4.4 Consequences of Improper Operation and Maintenance (O&M)
IMPROPER O&M CAN CAUSE POTENTIAL ENVIRONMENTAL
AND HEALTH PROBLEMS
In addition to causing the system to fail in accomplishing
its objective, improper O&M can cause adverse environ-
mental impacts and public health effects, odors, and may
impair wetland functions.
Without proper O&M, a wetland can become ineffective in its ability to
assimilate wastewater constituents. At worst, wastewater added to a wetland
could also cause adverse environmental impacts such as:
Breeding of flies, mosquitoes and other disease vectors (mosquito fish
can often discourage the growth of mosquitoes)
- Deteriorated water qualty and undesired release of nutrients to
downstream areas
Development of odors
- Increased populations of plants and animals considered to be pests
- Sludge accumulation inhibiting growth of organisms which require original
wetland substrate
- Accumulation of toxic heavy metals or other toxic compounds within the
wetland food chain, and
- Adverse impacts on protected species.
To avoid these impacts, O&M activities must be controlled keeping the
primary objectives of the wetland-wastewater system in mind. As new
information becomes available, individual wetland dischargers should be kept
abreast of advances. Carefully-conceived O&M activities, can prevent adverse
impacts to a wetland system.
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\o
SECTION 7
MANAGED WETLANDS CONSIDERATIONS
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7.0 MANAGED WETLAND CONSIDERATIONS
PROPER MANAGEMENT OF WETLANDS INVOLVES UNDERSTANDING PROCESSES
AND MONITORING
Management of wetlands leads to certain changes In
wetlands which should be understood and monitored. Arti-
ficial wetland systems may provide a reasonable alterna-
tive for some communities and contribute to establishing
design criteria.
The use of wetlands as part of a wastewater management strategy is a
relatively new concept despite the use of wetlands by some communities for
many years. To consider wetlands for widespread use, certain analyses must
be conducted. First, an understanding of the types and range of changes that
could occur in a wetland is important. Also important is the degree to which
wetlands assimilate or renovate wastewater. The acceptability of using
wetlands for wastewater discharges is contingent upon the understanding of
these issues. The data base on natural systems has increased, but certain
data limitations remain.
Another approach to the use of wetlands for wastewater management is the
development of artificial/aquaculture systems. This is also a new area of
endeavor, as only a few communities throughout the country have utilized this
approach. It is a viable approach, however, for many small communities and
information gained from the design of such systems may be applicable to
natural systems as well.
If a system is to be managed properly, management tools are helpful. A
major issue with wetlands systems has been the assessment of wasteload allo-
cations. However, with no models designed for that purpose for wetlands,
wasteload allocations remain a problem. Models, or analytical tools, are
discussed in Section 7.4 as they relate to the wasteload allocation process.
Finally, a managed system must be monitored adequately. In the case of
wetlands, monitoring should be conducted to assess not only the quality of
effluent entering and leaving a wetland but also the functions and character-
istics of the wetland. If a major goal of using a wetland area is to main-
tain its function and role as an ecosystem, such monitoring will be extremely
important.
Issues of Interest
• What types of changes occur in wetlands as a result of discharging
wastewater?
• Can wetlands1 functions and values be maintained?
• Are artificial wetland systems preferable to natural systems for waste-
water discharges?
• What types of artificial systems exist?
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7.0 Continued
• Can the effects of wastewater discharges on wetlands be predicted by
models?
• What can be done to monitor the impacts of wastewater on wetlands and the
effectiveness of wetlands in renovating wastewater?
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
KNOWLEDGE ABOUT MANAGED WETLANDS SYSTEMS HAS
INCREASED IN RECENT YEARS
Despite limitations in the data base, much is known about
the impacts of wastewater on some types of wetlands. Some
types remain unstudied, which could affect their accept-
ability for use.
This section is designed to parallel Section 4, Natural Wetland Char-
acteristics, which summarizes the characteristics, functions and processes
inherent to wetlands systems. With the addition of wastewater, or other
management measures, certain changes occur in a wetland. Some changes are
predictable. However, some are unpredictable based on the limitations of
knowledge regarding the impacts of management strategies on natural systems.
As existing wetlands discharges have received increased attention in
recent years, research on such systems has increased. For some types of wet-
lands systems, data have been collected not only on the impacts of wastewater
to wetlands but also on their ability to assimilate or treat wastewater.
Unfortunately, many wetlands systems have not been studied for their capacity
to receive wastewater.
The impacts of wastewater on wetland systems is interactive in nature.
The effects of changes in water chemistry and water quantity are not always
separable. Chan et al. (1980) have summarized the responses of ecosystems to
shifts in hydrologic regime related to velocity, renewal rate and timing
(Table 7.1). Ecosystem parameters of species composition, primary productiv-
ity, material cycling and nutrient cycling are evaluated in light of poten-
tial alterations due to changes in hydrologic regime. This analysis high-
lights the interactive changes which take place during ecosystem alterations
and illustrate the "interconnectedness" of ecosystem compartments.
Given the state of knowledge concerning wetland-wastewater systems, the
following sections summarize and evaluate the types of changes that occur in
wetlands used for wastewater disposal. Some changes can be objectively
evaluated (e.g., public health impacts), whereas others are more subjective
based on current knowledge (e.g., acceptability of species shifts).
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Table 7.1. Wetland Ecosystem Responses to Various Hydrologic Factors.
Ecosystem
Characteristics
Source
Velocity
Hydro!ogle factors
Renewal rate
Timing
Species composi ;ion
and richness
Primary
productivity
rv>
vo
o
Organic depositinn
and flux
Nutrient cycling
o Nutrient overload
may alter species
diversity
o Affects availability
of dissolved nutri-
ents for plant growth
o Sediment inflow in-
creases substrate
density, leading to
more vigorous plant
growth
o Salts, pesticides and
other toxins detri-
mental to productivity
o Affects distribution
X deposition of sedi-
ments, influencing ele-
vation and plant zonation
o Species richness found to
increase directly with
ve 1 oc i ty
o Increased velocity related
to greater sediment input
and increased plant growth
o "Edge-effect"--stimu-
lation of production
along channels due to
increased velocity
o Affects flow and avail-
ability of toxins
o Stagnant waters linked
to anaerobic conditions
and plant stress
o Dissolved oxygen related
to velocity
o Rate of total particu-
late and total organic
export directly propor-
tional to flow rate (and
velocity)
o Influences nutrient
loading and acidity
Ombrotrophic bogs--nutrient poor
Minerotrophic bogs--nutrient rich
o Provides vehicle for water
movement and circulation
o Uniform mixing leads to
monospecific stands to
vegetation
o Diversity tends to increase
with elevation, which is
influenced by flooding
duration 8 depth
o Availability of water
seems to control lat-
eral spread of ombro-
trophic bogs
o Availability of nutri-
trients for plant
growth related to
availability of water
o Regular renewal of water
in tidal areas minimizes
salt accumulation and
plant stress
o Regular renewal supplies
02, minimizing stressful
anaerobic conditions; depth
& duration of flooding most
important
o Increased flow rate
related to greater silt
input and organic matter
outflow
o Timing or seasonality
of rain input may affect
lateral and vertical spread
of ombrotrophic bogs
o Frequency of flooding
influences availability
of toxins to wetland
flora and fauna
o Influences mass loading,
transport and flux of
nutrients
o Flooding frequency directly
related to silt input and
organic matter outflow
o Soil organic concentration
increases on gradient from
actively flooded stream banks
to less actively flooded
inland high marshes
o Nutrient flux related to
timing of flooding with respect
to plant growth cycle.
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.1 Hydrology
THE EFFECTS OF WASTEWATER DISCHARGE TO A WETLAND ECOSYSTEM ON
HYDROLOGY RELATE DIRECTLY AND INDIRECTLY TO BUFFERING
The addition of wastewater to wetlands Increases surface
storage and soil moisture content and decreases the
wetland's ability to store excess rainfall. The addition
of wastewater reduces infiltration capacity, and increases
the probability of downstream flooding. If effluent is
rich in nutrients, plant growth is likely to accelerate
resulting in a reduction in total water input through
increased canopy interception and evapotranspiration.
Most effluent is likely to be stored as surface water;
this can change plant species composition and distribu-
tion.
Naturally functioning wetlands provide water, maintain water quality and
aid in flood prevention. When a wetland is altered through the addition of
wastewater, a change in water input occurs which causes direct changes in the
hydrologic regime of the wetland. This is clearly seen through an under-
standing of the hydrologic budget; when water inputs increase, a corres-
ponding increase in outflow must occur. When wastewater is applied to a
wetland ecosystem, surface storage increases, and the ability of the wetland
to store excess rainfall decreases. Thus, downstream inundation resulting
from an extreme rainfall event is more likely to occur.
Wastewater additions to wetland ecosystems also increases moisture
content to those wetlands not permanently inundated. This reduces the
downward movement of water through the soil surface resulting in a decrease
in the infiltration capacity. Higher water table levels and greater moisture
content prior to storm events increases downstream flooding probability.
Moderate applications of wastewater rich in nutrients usually accelerates
plant growth. Increased wetland vegetation would retard surface water flows
and reduce water inputs through canopy interception and evapotranspiration.
Also, if the loading of wastewater is significant enough to increase dis-
charge velocity, micronutrient availability to plants would increase.
Groundwater, surface area and soil pore space are the significant storage
areas for water inputs to wetlands. Continuous wastewater addition would
decrease the degree of seasonal fluctuations occurring in these storage
reservoirs through uniform effluent application. Infiltration and perco-
lation of effluent to groundwater areas depends on the physical components of
the soil. Most effluent is likely to be stored as surface water. Signifi-
cant increases in surface water force changes in plant species composition
and distribution which, in turn, may affect wildlife species abundance and
diversity.
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.2 Vegetation
VEGETATION IMPACTS SHOULD BE MINIMAL, OCCURRING MOSTLY AS
INCREASED PRODUCTIVITY
The impacts on vegetation in wetlands managed for
wastewater disposal generally result in increased growth
and biomass comparable to naturally productive systems.
Species replacement may occur, and successional trends may
be altered. Adverse effects have been found in wetlands
receiving wastewater, but these are not always the result
of domestic effluent inputs. Careful management is
stressed to avoid adverse impacts.
The plant community in wetlands employed for wastewater disposal is
affected by the management pattern in operation. A carefully administered
wastewater plan can be expected to increase productivity and cause few
perturbations in the vegetational community. The magnitude and severity of
the effects of wastewater on wetland plant communities are dependent on the
quality of the effluent, the amount of wastewater applied, the manner in
which wastewater is applied, and the ability of the existing wetland
ecosystem to assimilate wastewater.
The best documentation of impacts of wastewater on wetland vegetation is
derived from the Florida wetland studies. Impacts were noted in the struc-
ture, productivity and biomass components of wetland vegetation. Differences
in structural characteristics between cypress domes receiving sewage effluent
and control domes were most easily detected in those compartments with short
turnover times. For example, leaf biomass in the sewage dome was 1.4 times
higher than in control domes. The total leaf area index was more than twice
that in control area due to dense canopy (Lemna).
Comparisons of biomass, structure and productivity of domes receiving
effluent and other natural systems were made by Brown (1981). She found the
chlorophyll _a values for the sewage dome were similar to the values reported
for floodplain forests, tropical rain forests (2.3 g/m2, Odom 1920) and a
cove forest in the Smokey Mountains (2.2g/m2, Whittaker and Woodell 1969).
The high overall chlorophyll a in natural systems resulted from a combination
of high leaf area index (LAl]~and average leaf chlorophyll _a content. Con-
versely, the sewage dome achieved its high overall chlorophyll a value as a
result of an average LAI and high leaf chlorophyll _a content. ~
A marsh near Clermont, Florida, showed increased peak biomass in plants
receiving wastewater over those that did not. The presence of standing water
resulted in significant physical and chemical changes that affected plant
growth. Extensive growth of algae and floating plants was noted. Some
species, especially shorter grasses (Pancium sp.), declined in density from
increased competition, thus altering community structure. The low avail-
ability of oxygen may have limited some plants. Emergent plants such as
Sagittaria spp. are not limited by this factor since they are capable of sup-
plying oxygen to their roots through their vascular system. Micronutrients,
292
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7.1.2 Continued
phosphorus availability, and the generation of hydrogen sulfide (toxic to
root metabolism) were other factors considered as important deterrents or
stimulants to plant growth in this study. These factors are applicable in
evaluating impacts to vegetation in other wetlands.
Wastewater was reported to increase the Typha and Lemna biomass approx-
imately 30 percent at the effluent outfall in a Michigan marsh but changed
succession patterns (Kadlec et al. 1980). Algae was abundant, but effects
declined away from the outfall. Some species shifts were noted as
Polygonium, Utricularia and Myriophyllum densities declined, possible
outcompeted by Typha and Lemna. No effects on woody vegetation were detected
in the short-term study.
Significant detrimental impacts on wetland vegetation receiving sewage
effluents have been demonstrated in several instances. In a pilot project
with sawgrass marshes having limited nutrient uptake ability (Stewart and
Ornes 1975), the addition of wastewater severely upset the natural equil-
ibrium of this marsh vegetation. Tree ring analysis showed depressed growth
rates of cypress trees during the addition of raw and primary sewage to a
hardwood swamp near Jasper, Florida, over a period of 20 years. Small trees
and shrubs (red maple, Baccahris) replaced many dying cypress near the
effluent outfall to this swamp, but the causes were not obvious. A petroleum
spill, logging, toxic effects of raw sewage and hydroperiod alteration have
been suggested as possible causes, but actual causes have not been
determined. The cypress forest near Waldo, Florida, received primary
effluent without apparent adverse effects for over 40 years, so causes other
than normal effluent characteristics at Jasper are thought to contribute to
the observed changes there.
An Andrews, South Carolina, gum-tupelo swamp receiving wastewater
effluent has been reported to be severely damaged (J. Jones 1982). It has
not been determined whether the sewage effluent directly affected the swamp.
Indirect hydroperiod stress and catastrophic chemical discharge have also
been suggested as causes.
A cypress swamp adjacent to Lake City, Florida, was receiving domestic
effluent, but a large number of trees were reported as dead or dying. On a
recent staff field trip to this site, local sources indicated that salts from
a water softening agent were discharged into the swamp along with the
effluent and was the suspected cause for the severe impacts on vegetation
there. A hardwood swamp receiving effluent contiguous with Pottsburg Creek
near Jacksonville, Florida, was reported to have a high number of tree crown
kills. Winchester (1981) found that the distribution of tree kills in the
swamp was unrelated to effluent discharge points in the swamps. It was
suggested that hydroperiod alteration rather than effluent characteristics
was the cause of vegetation impacts.
On a long-term basis, subtle effects have been difficult to detect in the
sites studied, but several have been suggested on a generic level. Long-term
maintenance of a vegetation community requires replacement of mature organ-
isms. Concern has been expressed that a prolonged hydroperiod may prevent
seed germination for cypress and perhaps other woody species. Changes in
293
-------
7.1.2 Continued
water chemistry may influence successional trends. Monk (1966) suggested
changes from low calcium, pH and water levels to high calcium, pH and water
levels (similar to wastewater addition effects) will encourage shifts from
evergreen to decidious vegetation dominants in Florida wetlands. The
presence of wastewater also affects the rate of litter fall decomposition in
wetlands (Deghi 1976), and the long-term effects on peat composition and
accumulation are speculative. Other potential long-term impacts on
vegetation include the effects of wastewater on the frequency and severity of
fire in wetlands. Some wetlands are dependent on fire for maintaining their
vegetation composition (Monk 1969, Richardson 1980, Ewel and Mitch 1980).
Released from fire, vegetation species composition will undergo change in
these wetlands, which may or may not experience adverse effects.
On a generic level, the diversity of vegetation in wetlands of Region IV
makes the assurance of low impact from wastewater addition impossible.
Quantitative data are also lacking on the impact of wastewater on many
vegetation types within Region IV. Since vegetation is such an essential
component of wetlands, impacts from wastewater additions should be minimized
and carefully managed by controlling the quality and quantity of effluent
introduced to wetlands. Figure 7.1.2 shows the type of changes that could be
observed as a result of wastewater additions to wetlands.
294
-------
SWAMP SHRUB
UNDISTURBED
WBTLAND
CLEARED
LAND
8ULRUSM AQUATICS
SEDGE CATTAILS
THICKETIZATION
CLEARED LAND
DISTURBED
WETLAND
SEDGE
CATTAILS
m^m
^*t^r^H1^' ^"* ^^^^sT*?*^^"'"'*^™'*^
SWAMP
LOOSESTRIFE
t /
/ ¥. DUCKWEED
'*/ ALGAE
MINERAL SOIL
Figure 7.1.2. Potential modifications resulting from wetland management,
Source: Jaworiski and Raphael. 1978.
295
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.3 Nutrients
NATURAL CHARACTERISTICS IMPORTANT IN DETERMINING
NUTRIENT RETENTION
Removals of nitrogen and phosphorus reported for wetlands
receiving wastewater has varied from site to site. The
capacity to remove nitrogen is much greater than
phosphorus due to the atmospheric escape of nitrogen and
the excess of phosphorus in biological assimilation.
Nitrate is more easily removed than ammonium. Accurate
removal rates are difficult to assess due to lack of
hydrologic information. Long term capacity seems
promising at several sites, but should be evaluated on a
case by case basis. Impacts to vegetation are not
generally adverse. The abundance of some plant species
may be altered.
The natural nutrient transformation processes (Section 4.4.4) enable many
wetlands to satisfactorily assimilate and store increased levels of nutrients
from wastewater sources. In wetlands managed for wastewater assimilation,
conditions which maximize nitrogen and phosphorus removal are of primary
concern. Minor elements may be of concern on a local basis.
Nitrogen and phosphorus in domestic wastewater is present in several
organic and inorganic forms. The natural nitrogen to phosphorus ratio of
approximately 10:1 is frequently much lower (1:1 to 2:1) in domestic waste-
waters, causing an excess in phosphorus for biological assimilation. This
ratio varies with source of sewage and level and efficiency of pretreatment.
The impacts of nutrients are minimized by maintaining a high quality (low
nutrient) effluent. In numerous circumstances (Sloey et al. 1975) wetlands
have been shown to act as natural nutrient traps, some permanent, (domes,
peat, etc.) and others on a seasonal or intermittent basis (tidal marshes,
riverine swamps). The reported nutrient removal rates for those wetlands
receiving sewage effluent reflects the expansion of the wetlands capacity to
assimilate nutrients above the natural levels.
At Wildwood, Florida, (Boyt et al. 1977) reported an 89.5 and 98.1 per-
cent reduction for total nitrogen and phosphorus respectively in domestic
secondary sewage water, passing through a mixed hardwood swamp. At Waldo,
Florida, primary effluent total posphorus concentrations were reduced 51
percent in surface waters leaving a cypress strand and 77 percent after
passing through the soil profile into shallow groundwaters (Nessel 1978). A
69 percent reduction was reported for total nitrogen after secondary effluent
passed through mixed hardwood strand near Jasper, Florida (Tushall 1980).
Kohl and Mekin (1981) studied nutrient removal rates of a hardwater cypress
swamp south of Orlando. Total nitrogen concentration was reduced 88.1
percent but no corresponding total phosphorus reduction was observed. The
combination of the sandy soils and phosphorus-laden stormwater runoff were
factors cited as preventing observable phosphorus-removal. At Clermont,
296
-------
7.1.3 Continued
Florida, experimental natural marsh plots receiving secondary sewage effluent
reported 80 and 97 percent retention of total nitrogen and phosphorus as the
water passed through the soil profile (Zoltec et al. 1979). Experimental
chambers were located in the floodplain of a bottomland hardwood (cypress
tupelo) swamp in North Carolina to determine the assimilative capacity of
these systems for nitrogen and phosphorus (Brinson et al. 1981). These
authors suggested that the capacity for nitrate (N03) form was much greater
than the ammonia (NH4+) form of nitrogen. The nitrate was rapidly lost
through denitrification (see Section 4.4). Ammonia was accumulated until
conditions for nitrification and subsequent denitrification were present
(usually during summer drawdown). The rate of phosphorus accumulation was
reported to be proportional to phosphorus loading. These authors suggested
that the lack of an atmospheric pathway for phosphorus may limit the capacity
of swamps for long term phosphorus assimilation and long term sewage applica-
tion. However, increased particulate matter may provide long-term binding of
phosphorus. In analyzing nutrient levels and nutrient reduction, dilution
should not be confused with actual removal via nutrient removal pathways.
Some of the literature may be misleading in this regard and should be
properly interpreted.
The principal pathways by which nitrogen can be permanently removed from
a wetland is by denitrification or by hydro!ogic export. Export through
surface waters is a major loss for those wetlands with this capacity. Export
through groundwater has the advantage of additional filtering and treatment.
Because of the importance and sensitivity of conditions correct for denitri-
fication, (see Section 4.4.4), the manipulation of water depths and oxygen
conditions is essential to achieve good nitrogen removal via this pathway
(Sloey et al. 1980). Other chemical processes which are important in
nitrogen and phosphorus removal are co-precipitation and sorption reactions.
These reactions are important in nitrogen and phosphorus retention in the
soil profile. While the retention appears permanent for wetlands studied,
exceptions have been noted (Stewart and Ornes 1975).
As noted in Section 4.4.4, phosphorus has no significant means of atmos-
pheric loss and is highly dependent on physical-chemical reactions for re-
moval. Biomass uptake is also a route for storage of nutrients. In swamps,
the storage of nutrients in this compartment is larger than in marsh vege-
tation where biomass turns over on an annual basis (labile). Biomass storage
may be extended for long periods of times, for example, when nutrients became
stored in woody biomass. Excess phosphorus is stored in leaves of cypress
and gum (Brain 1981) in swamps receiving sewage. Other wetlands may use
roots as nutrient storage devices (Klopatek 1979). The leaf fall results in
some phosphorus leached from the leaves and returned to the surface waters.
The refractory constituents of litterfall continue to hold nitrogen and
phosphorus and may eventually form a permanent storage as peat.
The fate of nutrients in wetlands is important in understanding the
nutrient removal capacity. Sloey et al. (1978) have presented a diagrammatic
representation of sources, rates of transfer and storage compartments of
nutrients in wetlands receiving wastewater (see Figure 7.1.3). It is valu-
able in understanding the complexity of nutrient trapping and storage in
wetlands.
297
-------
7.1.3 Continued
In general, the addition of wastewater has resulted in increased levels
and storages of nutrients in wetlands. The impact has been favorable for
many wetland plants, however some species are replaced by those better
adapted to higher nutrient and hydrologic loadings (Sloey et al. 1981). This
loss of diversity may not be desirable in all circumstances, especially when
valuable wildlife and rare and endangered species are involved (Section 4.6).
Concern has been expressed over the ultimate retention capacity for
nutrient storage. Several long term studies have given conflicting results.
The persistence of nitrite and unionized ammonia forms of nitrogen are also
of concern due to their toxicity to fish (Kadlec 1978; Ruffier et al. 1981).
Florida sites have demonstrated long term assimilation capacity for nitrogen
and phosphorus (Nessel 1978, Tuschal 1981) but a California site displayed a
reduction in phosphorus removal efficiency (Whigham and Bayley 1979).
Because of the variability in wetlands, the nutrient retention capacity and
associated impacts must be evaluated on a case by case basis. Salient
factors important to this evaluation include hydrologic input and outputs,
soil profile composition, and the vegetational characteristics of the
wetland. The most limiting factors in evaluating the removal and retention
capacities of wetlands are the availability of accurate hydrologic
information for mass balance calculations and the long term prospects of
nutrient retention. Nutrient retention is especially important upstream from
lakes or reservoirs which might be sensitive to nutrient additions. However,
in riverine systems this may not be as critical if impacts on downstream
water bodies can be identified and assessed.
298
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INS
RAIN &
SURFACE
WATER
CULTURAL
WATER
GROUND -
WATER
«v
*
^
^
^
WETLAND
A
ATMOSPHERE
1 FREE-FLOWING
V
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aETATION
VJI
HI
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J
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l
WETLAND WATER
"
_*^
oi
1?I
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£95
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TRAPPED INTERSTITIAL WATER
J
RECEIVING
SURFACE
WATER
RECEIVING
GROUND-
WATER
STORAGE
COMPARTMENTS
Figure 7.1.3. Representation of nutrient storages and flows in wetland
ecosystems receiving wastewater ("cultural water").
Source: Sloey et al. 1978.
-------
7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.4 Wildlife
WASTEWATER DISPOSAL TO WETLANDS MAY HAVE ADVERSE AND
BENEFICIAL EFFECTS ON WILDLIFE SPECIES
A complicated array of interrelated biological and
chemical changes in natural wetlands subsequent to
effluent disposal may force changes on the existing
wildlife community. These changes are difficult to
quantify but usually result from changes in the flow rate
and water level and the structure and composition of vege-
tation. Alteration of the water and vegetation regime
will determine the presence of other impacts. Water
quality impacts to wildlife are usually determined by the
degree of treatment prior to disposal. Inadequate treat-
ment would reduce dissolved oxygen levels and increase the
presence of toxic substances. These impacts may lead to a
decrease in species richness through increases in the
occurrence of wildlife diseases.
Potential changes in the wildlife community of a wetland ecosystem
resulting from managed wastewater additions may occur from a complicated
array of interrelated biological and chemical changes in the wetland. Most
of these changes would be secondary, but several direct impacts may also
occur. Potential wildlife impacts are difficult to quantify and evaluate
completely because they usually involve dilatory shifts in natural wetland
parameters. Specific studies are lacking in the southeast on the potential
changes and impacts to wildlife from the addition of wastewater. In general,
major wildlife impacts would result from changes in the following:
flow rates and water level
structure and composition of vegetation
amount of edge
availability of food
These changes are interrelated, and in many instances, the degree of one
impact will determine the presence and degree of another. Changes in flow
rates may change the types and densities of escape cover. Water level
changes may force changes in the distribution and composition of plant
species, and this could alter the horizontal and structural diversity of the
wetland plant regime. Thus, changes in flow rates and water levels deter-
mine, in part, changes in structure and composition of vegetation and avail-
ability of food. Food availability alters the carrying capacity of a wet-
land; if this occurs, distinct changes in wildlife species composition are
possible.
Changes in water quality after subsequent discharge of treated effluent
may cause indirect changes in the wildlife community. Increases in nutrient
levels can alter macroinvertebrate, algal and insect populations. Changes in
pH and alkalinity may impact fish populations and plant species composition,
distribution and biomass. Increased sedimentation may eliminate submerged
300
-------
7.1.4 Continued
plants, and reduction in levels of dissolved oxygen may depress normal levels
of algal and invertebrate populations. The above impacts could eventually
lead to changes in species richness and species diversity through alterations
in the quality and quantity of available food.
Wildlife impacts would also be controlled by the degree of wastewater
treatment prior to disposal. Poorly treated effluent may be associated with
heavy metals and viral or bacterial pathogens. Absorption of these
constituents by plants and invertebrates may lead to bioaccumulation and
increases in the occurrence of wildlife diseases.
In Region IV, few long-term studies have been conducted on wildlife
impacts resulting from wetland disposal of treated effluent. Harris (1975)
studied the effect of sewage effluent on wildlife species endemic to Florida
cypress domes. Most benthic invertebrates, fish and juvenile amphibians were
eliminated from a dome receiving effluent rich in organic material. Insects
concentrated in the center of the dome, which increased the number of frogs
present, but anaerobic conditions limited tadpole development. Several
migrating passerine bird species increased drastically in numbers during the
winter and spring because fly populations increased.
General estimates of the effects of wastewater discharge on wildlife may
be inferred from studies outside Region IV. Kadlec (1979) reported no major
shifts in species richness or species diversity at a Michigan lake treatment
site after two years of wastewater discharge. Possible long term effects,
however, could not be quantified. Studies on the beneficial and adverse
effects of effluent discharge on wildlife populations and habitats of wetland
ecosystems would prove helpful in assessing the long-term impacts of a
wetlands discharge.
301
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.5 Public Health Impacts
MECHANISMS TO REDUCE POTENTIAL PUBLIC HEALTH PROBLEMS EXIST
BUT ARE NOT FAIL-SAFE
Although many types of wetlands remain unstudied in Region
IV, studies from Florida suggest that wetland soils are
excellent natural barriers against groundwater
contamination. Surface waters adjoining wetlands
receiving wastewater may acquire some contamination if
detention time of treatment is not sufficient. Exotic
diseases were not found to be amplified by wastewater
addition to wetlands.
The public health implictions of wastewater recycling in wetlands have
not been fully evaluated for all natural wetland types in Region IV. Poten-
tial adverse impacts include increasing the threat of waterborne disease (via
surface or groundwater contamination) and increasing the incidence of
insect-, bird-, or mammal-vectored diseases. Several Florida wetland types
have been studied in this regard, and much current knowledge is derived from
these studies. No study to date has been designed to provide direct epi-
demiological evidence on this subject.
A substantial reduction (90-99 percent) in bacteria (Fox and Alison 1978,
Zoltec et al. 1979) and viruses (Scheuerman 1978) has been observed in waste-
water passed through typical marsh (peat) and cypress dome soil profiles of
peat, sand and clay mix. However, Sheuerman (1978) demonstrated that binding
was not permanent, and viruses could be released from the soil profile under
certain conditions. Wellings (1978) isolated viruses from a well at the same
cypress dome experimental site, demonstrating that although the soil profile
retained viruses and bacteria, it was not a fail-safe system.
Those wetlands receiving wastewater that interconnect with other bodies
of water (lakes, streams, etc.) could potentially transmit bacteria and
viruses. At the Jasper experimental site, fecal and total coliforms were
exported at variable rates, depending on the detention time of the strand
(Brezonik et al. 1981). Generally, the longer the detention time, the
greater the sedimentation and die-off of coliform populations. Wells moni-
tored at this site indicated a limited sphere of contamination extending
vertically in the limestone surrounding the swamp, but groundwater supplies
were basically protected (Brezonik et al. 1981).
Concern has been expressed over the possible amplification of the enzoo-
tic eastern equine encephalitis (EEE) vectors in swamps receiving sewage
(Davis 1975). Possible increase in bird and mosquito populations associated
with EEE was the basis for concern. Subsequent study (Davis 1978) of EEE
vectors of mosquitos and sentinel birds demonstrated that EEE activity was
not substantially greater in cypress domes receiving sewage than in natural
domes. Although known EEE mosquito vectors (Culiseta melanura, Culex
nigropalpus) increased, human nuisance mosquitos[Aeries iTrTirmata, Aedes
atlantica) declined due to elimination of habitat in this case. Mosquito
302
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7.1.5 Continued
populations elsewhere may react differently and concern has been expressed
over the amplification of nuisance mosquito populations, but this has not
been field verified.
Other public health aspects of wastewater discharges to wetlands remain
uncharacterized. For exmple, the persistance of nitrite resulting in contam-
ination of drinking water supplies presents potential toxicity problems,
especially for infants (methemoglobomenia). Un-ionized ammonia compounds are
directly toxic to fish and other creatures (Ruffier et al. 1981). The
effects of adverse weather conditions (storm events, freezing, etc.) on
treatment efficiency are unknown, and the long-term capability of soil layers
to protect groundwater resources is not fully understood. While sufficient
data exist to indicate the potential for public health problems arising from
wetlands discharges, no incidences of disease resulting directly from such
discharges have been identified.
303
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7.0 MANAGED WETLAND CONSIDERATIONS
7.1 Impacts to Natural Characteristics
7.1.6 Natural and Artificial Wetlands
LOWER COSTS ASSOCIATED WITH NATURAL WETLANDS
Artificial and natural wetlands are capable of providing
cost-effective upgrading of domestic effluents. Artifi-
cial wetlands may have higher O&M costs but are more
amenable to multiple-use management plans and handling
industrial effluents. Natural wetlands have been reported
to be more efficient at removing BOD but less efficient at
removing nitrogen and phosphorus.
The utility of natural and artificial wetlands has been demonstrated in
many instances as effective tools in upgrading the quality of domestic
effluents. The overall advantage of one system over the other is dependent
on many site specific variables and general treatment objectives. Tradi-
tionally, artificial wetlands are engineered systems designed to provide
treatment of a variety of effluent types. In this regard, artificial systems
generally provide for greater reliability and predictability of the treatment
process and its products than are observed in natural systems.
Artificial and natural treatment alternatives are land-intensive compared
to conventional treatment systems. Given a natural wetland of adequate size
and reasonable proximity to a wastewater treatment plant, the artificial
wetlands treatment system is generally more capital and energy intensive than
a natural wetland of equivalent capacity. This, however, would depend great-
ly on the design of the artificial/aquaculture system and largely on its
degree of mechanization. The O&M costs of artificial systems also tend to be
higher; however, extensive environmental surveillance of natural wetlands
used for wastewater may equalize these differences. This fact again high-
lights the site-specific nature on which these factors must be analyzed.
Artificial systems, in addition to possessing greater predictability, are
reported (Table 7.1.2) to be more efficient in removing phosphorus, COD and
nitrogen from wastewater than are natural wetlands. These ranges were de-
rived from field data and illustrate the variability among and between arti-
ficial and natural systems. Slightly greater BOD removals were reported for
natural than for artificial wetlands. The low phosphorus removal reported
for both systems suggests that some type of pre-treatment for phosphorus may
yield quantifiable benefits.
Artificial wetlands offer potential benefits of harvestable biomass for
food or energy production. Forested natural wetlands receiving wastewater
have also been cited for additional use in harvestable timber management
plans. Natural wetlands have additional benefits of water conservation and
greater embodied habitat and wildlife potential.
In the final analysis, site-specific factors and treatment objectives
dictate the system most desirable for a specific area.
304
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Table 7.1.6. Reported Removal Efficiency Ranges for the Constituents in
Wastewater in Natural and Artificial Wetlands.
Removal efficiency, %
Constituent
Total solids
Dissolved solids
Suspended solids
BOD5
TUC
COD
Nitrogen (total as N)
Phosphorus (total as P
Natural wetlands
Primary Secondary
40-75
5-20
60-90
70-96
50-90
50-80
40-90
) 10-50
Artificial
Primary
50-90
50-90
30-98
20-90
wetlands
Secondary
Refractory organics
Heavy metalsa 20-100
Pathogens
^Removal efficiency varies with each metal.
Source: Tchobanoglous and Gulp. 1980.
305
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7.0 MANAGED WETLAND CONSIDERATIONS
7.2 Monitoring
7.2.1 Water Resources
QUANTITATIVE ANALYSIS OF THE MAJOR WETLAND HYDROLOGIC
PROCESSES IS DIFFICULT
Measurement of the major hydrologic Inputs and outputs of
a wetland ecosystem is difficult but necessary if proper
effluent loading and assimilation rates are to be
established. Precipitation measurement is difficult
because of the extreme local and microscale variability of
precipitation at ground level. The difficulty involved in
measuring surface water relates to channel boundary
determination and estimates of sheetflow. Measurement of
groundwater resources is limited by financial concerns.
Evapotranspiration is usually estimated as the difference
between precipitation and discharge, thus introducing
difficulties involved in estimating these parameters.
Quantitative measurement of water inputs and outputs in a wetland
ecosystem is difficult because of the complexity of interrelated hydrologic
processes and the difficulty involved in measurement itself. Climatic
variations compound the situation, but monitoring of precipitation, surface
water, groundwater and evapotranspiration would allow the assessment of
effluent loading and assimilation rates for a wetland. A brief discussion of
measurement techniques for these hydrologic and climatic processes is
presented below.
Precipitation
The standard rain gauge is a cylindrical open topped vessel that modifies
the windfield in its immediate vicinity, causing a deficiency in catch that
increases with wind speed. The local and microscale variability of rain in
wetland areas introduces a large degree of uncertainty with regard to aerial
interpretations. Because of this, aerial weighting techniques such as the
Thiessan and Isohyetal methods have been developed to take into account
ground level variabilities associated with atmospheric and topographic
influences.
Surface Water
Surface water inputs and outputs are usually computed in terms of
volumes, depths or average flow rates for months, seasons and years. The
flow rate in natural wetland channels may be described in terms of its stage
and velocity. Stage and velocity data are used to determine discharge rate.
Since the cross-sectional area of flow and the change in velocity across the
stream segment in question are needed to develop flow rates, boundary deter-
minations for the stream channel and catchment divide must be determined.
Unfortunately, surface water runoff usually does not exit a wetland area
through a single outlet, and sheetflow often results from intense storm
events (Daniel 1981). Sheetflow inputs and outputs are difficult to measure;
the Chezy-Manning equation has been modified for estimating sheetflow, but
306
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7.2.1 Continued
few published estimates of Manning's roughness coefficient exist for wetland
ecosystems (Carter et al. 1978).
Groundwater
In most cases the measurement of groundwater inputs and outputs are
limited by time and money. Observation wells are needed to establish
potentiometric surfaces so directions of flows can be determined. A
piezometer is the basic device used for the measurement of hydraulic head,
and several piezometers are needed to determine hydraulic gradients. Once
the hydraulic gradient has been estimated, Darcy's law is used to obtain
specific discharge. The hydraulic conductivity (K) factor in Darcy's law is
a function of the density and viscosity of water and the physical properties
of the aquifer itself. Carter et al. (1978) lists several studies that have
developed techniques for measuring hydraulic conductivities. By applying
Darcy's law, standard techniques can be used to determine not only specific
discharge but also porosity, specific yield and head.
A practical but precarious method of estimating groundwater inputs and
outputs is to determine groundwater as the residual in the water budget
equation. Unfortunately, all errors associated with measurement of other
budget components accumulate and appear in final estimates of groundwater
inputs or outputs.
Evapotranspi ration
Evapotranspiration losses from wetlands cannot be measured directly but
must be estimated as the residual in either water or energy budget equations
by use of standard field techniques or by empirical methods such as those
proposed by Thorwaithe and Mather and Penman. The determination of
evapotranspiration as the residual in the energy or water budget equation is
considered the most accurate estimate of total evaporation losses. Standard
field techniques include National Weather Service Class A evaporation pans
for determining evaporation from a free water surface. Lysimeters are used
to measure normal evaporation from bare soil or evapotranspiration from vege-
tated areas. Wang and Heimburg (1976) estimated evapotranspiration from a
cypress dome aquifer by analyzing groundwater level fluctuations. Brown
(1981) measured total vaporization losses in three cypress domes in Alachua
County, Florida by monitoring water vapor changes in plastic chambers
enclosing plants in the dome system.
307
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7.0 MANAGED WETLAND CONSIDERATIONS
7.2 Monitoring
7.2.2 Water Quality - Aquatic Ecology Monitoring
POSSIBLE MONITORING NEEDS AND METHODS ARE DESCRIBED
A monitoring effort can be limited to the discharge from
the system, or it can include the wetland system itself.
For each parameter to be monitored, sample timing,
frequency, and location must be established.
In general, an owner of a wastewater treatment plant will monitor what
the state environmental protection agency or the EPA require. Because
wetlands are highly dynamic systems that are more complex and less understood
than typical receiving waters, monitoring may need to be more intensive and
extensive than for more conventional types of wastewater management systems.
Considerations for a monitoring effort include parameters to be measured,
timing and frequency of monitoring, and sampling locations. Quality control
and the need for scientist and technician training are also important.
A key decision which needs to be made for each wetland wastewater system
is whether the wetland system itself is to be monitored as part of the
environment receiving wastewater or only the water released from a wetland.
Monitoring activities can be based on viewing a wetland as a "black box",
monitoring along transects or at specific locations, or monitoring at
assorted locations as a function of time.
Items related to monitoring activities are the following:
- Parameters which could be measured: five-day BOD, total organic carbon,
total suspended solids, various forms of nitrogen and phosphorus,
chlorine residual, selected metals, selected organic compounds, and
various biological indicators of health hazards (pathogens, coliforms,
and other organisms).
Effects of toxic substances would need to be measured in isolated
conditions where all but one parameter can be controlled (EPA 1981).
For invertebrate analyses, use of an indicator species is considered an
effective method (EPA 1981).
- Concentration of metals within vegetation under natural conditions can
not be utilized as indicators of metal uptake or treatment efficiency,
because many variables affect metal uptake, such as climate and soil
conditions, types of plants and availability of metals (EPA 1981).
- Monitoring of metals, particularly calcium, potassium, magnesium, zinc,
iron, and manganese would allow the extent to which metals accumulate
within the food chain to be measured. Both water column, sediment and
plant material would need to be monitored. Such an effort would be best
conducted by a university or a research institute.
308
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7.2.2 Continued
- Chloride concentrations can be measured to indicate the dilution which
wastewater has undergone.
- Sampling of water in monitoring wells along the perimeter of a wetland
would help assess lateral percolation of wastewater constituents through
the soil.
- 24-hour composite sampling is needed to establish mass balances through a
system for any wastewater constituent of interest (O'Brien 1980).
- Non-wastewater hydrologic input and outputs should be evaluated in
wetlands receiving wastewater. It can be done with simple rain gauges,
and gauging stations. This is important to understanding the impact
wastewater has on endemic hydrologic flows and may assist in indexing the
assimilative capacity of the wetland.
- Monitor for adverse changes in the structure and function of vegetational
community. The methods employed must be tailored to the dominant vegeta-
tion type (emergent, submergent, tree, shrub). Methods previously
employed include aerial photography (especially infrared), harvest
methods, litter fall estimates, gas exchange productivity chambers, and
simple point-quarter counts.
- Detailed cycling should be monitored by litter bag studies, or sediment
composition and accrual analyses.
- Use of sentinal birds to monitor for enzootic disease (encephalitis).
- Monitor nuisance insect populations for possible amplification of disease
vectors,
- Establish and monitor control areas for appropriate parameters (vege-
tation, wildlife, sediments, chemical parameters).
Supplemental funding would be needed by a treatment plant owner to
implement the more sophisticated monitoring activities if they prove to be
necessary to properly assess and monitor a wetlands discharge. Selection of
monitoring activities may vary for each wetland wastewater system. These
issues will be addressed by Phase II.
309
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7.0 MANAGED WETLAND CONSIDERATIONS
7.3 Analytical Tools
7.3.1 Wetland Ecosystem Modeling
FEW MODELS EXIST WHICH CAN BE USED EFFECTIVELY FOR
ESTABLISHING EFFLUENT LIMITS
Existing wetland models have been developed for specific
ecosystems and only simulate particular environmental
processes applicable to certain geographic regions.
Models have been developed to simulate ecosystem processes
and Impacts for cypress domes and bottomland hardwood
swamps. Other wetland ecosystem models that integrate a
wide range of wetland environmental parameters are needed.
The inherent difficulties involved in quantifying hydrologic processes
associated with wetland ecosystems have resulted in few wetland models being
developed. Existing models are simplified and can only be applied to speci-
fic wetland types. Carter et al. (1978) examined three approaches to
hydrologic modeling and referenced pertinent studies. Whitlow and Harris
(1974) reviewed modeling attempts to predict the impact of flooding on vegeta-
tion. The authors stated that few models are available for direct use in
assessing the impacts of floods on woody vegetation because extensive empir-
ical data on species tolerance and occurrence in the immediate locale is
needed. Ecosystem processes and impacts have been modeled in detail for
cypress domes in Florida.
Wang and Heimburg (1975) developed a water budget model for Florida
cypress domes, calibrated for two different years and for three different
domes. Layland (1975) simulated the major ecosystem interactions between
cypress swamps and watersheds based on a conceptual energy model developed by
H. T. Odum (1971). Auclair (1975) has developed a model that simulates the
fate and effects of total phosphorus levels in natural and effluent-treated
cypress domes.
Similar models have been developed for bottomland hardwood ecosystems.
MacCullum (1980) developed a dynamic mathematical model of the zone of aera-
tion for bottomland hardwood swamps describing the vertical distribution of
water available for vegetation use. A forest simulation model (swamp)
developed by Phipps (1979) simulates the effect of flood frequency and depth
to water table on floodplain forest vegetation dynamics. Franz and Bazzaz
(1977) constructed a similar model that describes the distribution of bottom-
land vegetation as a function of flood-stage probability to predict changes
in species distribution resulting from stream impoundment. Hopkinson and Day
(1980) have modeled hydrology and eutrophication processes in a Louisiana
swamp forest.
r ev
models developed for specific wetland types can be modified and adapt-
ed for use in other ecosystems. Gupta (1977) developed a broad model appli-
cable to many wetland ecosystems that explores the response of ecosystem
physical parameters to a planned wastewater addition. The model keeps track
of inputs and outputs over time for a particular ecosystem, thus developing
general trends that can be expected for certain changes in inputs such as
310
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7.3.1 Continued
wastewater loading rates. Mitsch et al. (1982) provides the most recent
review of models of freshwater wetlands in North America. These models
generally cannot be utilized to assess loadings to wetlands or impacts from
discharges. Therefore, basing NPDES Permits on modeling is probably not
appropriate for wetlands based on current knowledge and models.
311
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7.0 MANAGED WETLAND CHARACTERISTICS
7.3 Analytical Tools
7.3.2 State Modeling Efforts
NO STATE USES A SPECIFIC WETLAND MODEL FOR DETERMINING
EFFLUENT LIMITATIONS
North Carolina and Tennessee have modeled wetlands for
wasteload allocations using a modified form of the
Streeter Phelps model. South Carolina has modeled swamps
using a standard water quality model developed by the
Texas Water Quality Board. The remaining states have not
modeled wetlands as part of any permit application
program.
Most states in Region IV use various water quality models to aid in
issuing NPDES permits and establishing effluent limitations. The models are
generally used to estimate the assimilative capacity of a water body and the
maximum wasteload allocation. Water quality models are designed to apply to
streams or rivers where flow is one dimensional; only advective transport is
simulated and steady state conditions are assumed. Wetlands in general do
not have these characteristics, but the lack of specific models applicable to
wetland ecosystems and the absence of a sound wetlands data base have forced
most states to either use stream models or make qualitative evaluations.
Inherent problems with modeling wetland systems are related to topography
and life cycle changes. In order to properly model an aquatic system, flow
paths need to be defineable; flat topography and lack of defined channels
allow flow paths to vary easily from day to day and from season to season.
In addition, biochemical roles of life forms vary with life cycles.
Steady-state conditions are rarely observed.
Flori da
No wetland modeling has been conducted by Florida as part of an effort to
establish effluent limitations.
Georgia
Georgia uses a modified version of the DOSAG model developed by the Texas
Water Quality Board. The model is applicable to unbranched river segments
and has not been used for wetland analyses.
K.entuck^
The State of Kentucky has developed a general broad-based dissolved
oxygen model to be used for setting permit limitations for wetland ecosystems
as well as other water bodies. The model has not been used to date because
no penult applications or issuances for wastewater discharges to wetlands
exist.
312
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7.3.2 Continued
Mississippi
Mississippi State University has developed a Standard Water Quality Model
called AWFRESH for determining effluent limitations for streams where little
or no field data are available. Bayous with and without flow are not
modeled, but a qualitative judgment is made concerning the effect of an
anticipated discharge on water quality.
North Carolina
A modified form of the Streeter Phelps model is used to determine
effluent limits for wetland ecosystems in North Carolina.
South Carolina
South Carolina models swamps that have definable channel geometry and
obvious flow using DOSAG II, a standard water quality model developed by the
Texas Water Quality Board.
Tennessee
Tennessee does not differentiate between wetlands and stream discharges.
Because of this, a modified form of the Streeter Phelps model is used to
establish limits for these water bodies. For wetlands where little or no
flow exists, a lake model similar to that developed by Chen and Orlob is
used.
313
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Wastewater N. •
Addition / .
Unconsoli-
dated
Sediment
SECTION 8
RANGE OF KEY FACTORS
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8.0 RANGE OF KEY TECHNICAL FACTORS
ENVIRONMENTAL FACTORS ARE EQUALLY IMPORTANT AS ENGINEERING FACTORS
IN EVALUATING WETLANDS WASTEWATER DISCHARGE
The key technical factors which must be evaluated include
traditional engineering considerations and nontraditional
environmental and management evaluations.
The key factors identified in this section reflect technical areas of
importance which must be evaluated by decision makers involved in the design,
operation, monitoring or permitting of wastewater discharges to wetland
areas. The unusual nature and great potential of the wetlands-wastewater
interface demands unique sets of design, operation, and permitting criteria.
In addition to the traditional engineering criteria (unit processes, nutrient
loading, hydrologic loading, BOD, SS, etc.) wetlands receiving wastewater
require a different approach to operational and environmental management
considerations.
The key criteria traditionally involved with an engineering assessment of
wastewater disposal are summarized in Section 8.1. Included in that discus-
sion are ranges of observed values which have been noticed in wetlands
receiving wastewater.
The key environmental/managerial factors that determine the feasibility
of a wetlands-wastewater discharge are presented in Section 8.2. These en-
vironmental criteria, because of the uniqueness of wetland systems, must be
evaluated equally with the traditional engineering considerations. The
environmental/managerial criteria take into consideration the assimilative
capacity of the wetland and the potential environmental costs of wastewater
application to wetlands.
From an implementabi 1 ity standpoint, the use of a wetland site for the
disposal of wastewater can be declared unfeasible if these key engineering
environmental criteria are not satisfied. A wetland site may also be
undesirable for use as a wastewater management option if one of the many
factors discussed in this report are not satisfied. These key technical
factors are put forth as the most likely limiting factors in the implement-
ability of a particular wetlands-wastewater disposal system.
Issues of Interest
0 Can reliable design criteria for wetland-wastewater systems be based on
existing information?
0 Can engineering design overcome the limitations of particular wetlands?
0 What are the most important factors that should be considered during
design?
0 What conditions preclude the use of a wetland from any wastewater dis-
charges?
315
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8.0 RANGE OF KEY TECHNICAL FACTORS
8.1 Key Engineering Considerations
HYDRAULIC LOADING AND DETENTION TIME REQUIREMENTS
ARE KEY ENGINEERING CRITERIA
The key engineering considerations involved with
discharges to wetlands focus on hydrologic elements*
nutrients and other water quality parameters. The
feasibility of wetlands utilization for alternative
wastewater management schemes is dependent on these key
engineering factors.
A multitude of engineering considerations are involved in the planning,
design and operation of any wastewater management system. Factors such as
facilities planning and preliminary design, detailed design, installation and
operation and maintenance, have been discussed in Sections 6 and 7. Comple-
tion of each of these engineering tasks is necessary to implement a
wastewater management plan. Wetlands systems incorporated into wastewater
management plans are subject to these and other constraints.
Hydrologic factors are key considerations in determining pollutant re-
moval efficiencies. The relationship of important hydrologic parameters to
several pollutant removal mechanisms known to occur in wetlands is presented
in Table 8.1. This summary demonstrates the importance of hydrology to pol-
lutant removal and the complexity of the processes involved. The importance
of interdependence of hydrology, water quality and ongoing ecosystem
processes are also highlighted by the information provided in Table 8.1.
The hydrologic loading rate of wastewater to wetlands is one of the key
engineering factors for a particular wetlands discharge. The hydrologic
loading rates for several wetlands are presented in Section 8.1.1 and are
intended to serve as guidelines for what has been observed or proposed for
each wetland system discussed. The observed values are based on a limited
number of field investigations and are not intended to be applicable to all
wetland systems. Water quality considerations such as nutrient loadings,
BOD, pH and dissolved oxygen are of primary importance and influence
engineering considerations. Their specific limits and influences on wetlands
receiving wastewater are presented in Section 8.1.2.
316
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Table 8.1. Relationship of Hydroloqic Factors to Pollutant Removal in Wetlands.
Major pollutant removal mechanisms
Hydrologic
factors
Sedimentation
Aeration
Biochemical transformations
Sediment/Soil adsorption
Circulation and Beaver dims beneficial in Internal circulation
flow distribu- dispersiig flow over meadow- important in distributing
tion (cont'd) lands tc enhance sedimenta- 02 from surplus to deficit
tion and filtration. areas
Circuitcjs flow paths and
sheet fl )w lead to large
settling areas and good
sedimentation.
Broad flow distribution leads
to large effective areas for
biological contact and high
removal rates.
Turbulence and
wave action
Seasonal and
climatic
factors
Most dranatic sediment re-
ductions associated with
storm ep'sodes in meadow-
lands--more even flow dis-
tributior over wetland.
Soil saturation
Lowering of water table leads
to aeration, mineralization
and greater mobilization of N.
G.W. table within 5-10 cm
of wetland surface promotes
anaerobic (reducing)
condi tions.
Soil-water interface essential
as major site of sorption,
deactivation and denitri fication.
Reaeration a function of
channel roughness.
Wind can be important in keep-
ing localized parts of wetland
water aerated and mixed.
Pond and pond-like areas
nearly depleted of DO in
summer and supersaturated
in winter and spring.
Nitrifying and denitrifying
bacteria limited in activity
during drought or low water
temperatures.
Freezing promotes release of
N and P from plants and soils
for subsequent washout.
Spring snow melt appears to
have flushing effect on
nutrients.
Best plant uptake of nutrients
in spring-summer growth period.
First flush of wet season may
wash out decaying organic matter
from prior winter.
Temperate systems experience
winter release of nutrients.
Seasonal rainfall and runoff im-
portant as diluting agent and to
encourage water circulation.
Level of soil saturation controls
microbial activity.
Higher respiratory activity and
biological decomposition with
well drained soil conditions.
-------
Table 8.1. Continui;d
CO
Hydrologic
factors
Sec. imentati'on
Soil saturation
(cont'd)
Permeabi1ity
and groundwater
movement
Source: Chan et al. 1981.
Major pollutant removal mechanisms
Aeration
Biochemical transformations
Lowering of water table allows
aeration and decomposition of
organic matter and slug release
of nutrients in next flush of
runoff.
Source and amount of g.w.
inflow influences pH and
resultant solubility and
precipitation reactions.
Sediment/Soil adsorption
Seepage wetlands nay act
similarly to flood-irriga-
tion forage grass systems in
virtual completeness of P
removal.
Nitrogen removal through
nitrification/denitrification
may be excellent in surface
soils and shallow seepage zone.
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8.0 RANGE OF KEY TECHNICAL FACTORS
8.1 Key Engineering Considerations
8.1.1 Hydrologic Parameters
HYDRAULIC LOADING AND GROUNDWATER RECHARGE ARE KEY
HYDROLOGIC PARAMETERS
Hydraulic loading rates and the extent of groundwater
recharge are identified as key hydrologic parameters which
affect wetland utilization. The importance of adequate
detention time and maintenance of acceptable water depths
are also stressed for optimum treatment and for minimizing
adverse environmental impacts.
The hydrologic loading rate is a key engineering consideration in the
design of artificial or natural wetlands-wastewater management systems. This
study has shown that although many wetlands within Region IV are unin-
tentionally or intentionally part of a wastewater management strategy (see
Section 2.2.3), few have been studied in this most important regard.
Appropriate hydrologic loadings are dependent on endemic hydrologic patterns,
soils and the extent to which changes in wetlands ecosystems are acceptable.
Ranges of observed loading rates for several natural and artificial wetlands
are presented in Table 8.1.1. Hydrologic loading rates for hydrologically
isolated natural wetland systems ranged from less then 1 to 13 cm/wk. Hydro-
logically open, natural wetland systems had a similar range of observed
loading rates. The data base for this table is from Florida studies and may
not apply to similar systems in other states on a year-round basis. The
diversity of wetland types also requires that great care be used in applying
these observed values to any wetland system. These hydrologic loadings have
been expressed on a cm/wk basis. The loading rates for hydrologically
isolated systems give a slight indication that they have a lesser loading
capacity on an area! unit basis than the generally larger, hydrologically
open systems. This raises the question of the relationship between per unit
capacity and catchment basin size which has not yet been resolved.
Water depths may become a limiting factor if existing vegetation in
natural systems is not adapted to extensive and deep flooding. Cypress and
gum are naturally adapted for the deepest areas but rarely tolerate depths of
>2m for prolonged periods. Consistent depths of >lm may limit some wetland
types for long-term application since seeds from some endemic species
(cypress) will not germinate and survive in deep water. Marsh applications
may be limited by depth of flooding that exceeds the range of flooding to
which they are adapted. Greater than usual depths may also limit diffusion
of metabolites and gases which tend to exacerbate the physiological problems
created by flooding (see Section 7.1). Many wetland communities are adapted
to cyclic flooding (bottomland hardwoods, other riverine wetlands espe-
cially). Cyclic applications of wastewater may be a more successful applica-
tion methodology to avoid the stress created by maintaining consistent water
depths. Fritz and Helle (1979) suggested that sheetflow (versus channelized
flow) should be maintained in wetland strand systems to improve efficiency of
treatment.
319
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8.1.1 Continued
Detention time is difficult to quantify in many wetland systems.
Removal efficiencies decline in hardwood and cypress strands when high
hydraulic loadings wash out nutrients before they can be assimilated or
otherwise removed. Considering detention time as a flood duration factor,
some wetlands may be excluded because they are strictly adapted to infrequent
flooding and tolerate standing water for only short durations (bottomland
hardwoods for example). Sloey et al. (1978) indicate that palustrine
wetlands (nontidal wetlands not confined by channels and not marginal to
lakes) are more amenable to management for wastewater treatment than are
other major wetlands (tidal, riverine, lacustrine) because palustrine
wetlands are hydraulically isolated from open surface water, and hydraulic
residence times are high. Fritz and Helle (1979) determined that a cypress
strand receiving secondary effluent near Jasper, Florida, has detention times
ranging from 4 to 64 days with an average of 32 days. Treatment efficiencies
were quite variable as a result. Their ultimate recommendation was that
detention time in a wetland should average 30 days with a path length of
discharge of 1500 feet, or any combination which results in a detention time
sufficient to convert most of the nitrogen to nitrate form.
Soils are another key engineering consideration. Sutherland and Bevis
(1979) suggested that hydraulic conductivities of 10-4 to 10-5 cm/sec would
be desirable for wetlands receiving wastewater. They felt that this rate of
percolation would provide adequate detention time for the trapping and
degradation of wastewater constituents.
On a physical-chemical basis, underlying clay mineral soil layers have a
greater capacity to adsorb and retain nutrients and pathogenic microorganisms
than do organic soils. This characteristic is important in protecting
groundwater supplies from contamination and relates to the geologic history
of the area. Conversely, highly organic soils in wetlands indicate that
organic matter is accumulating due to certain biological and hydrological
conditions. These systems seem to be more amenable to increased nutrient
uptake and long-term storage in biomass than those wetlands with strictly
coarse mineral alluvial soils.
Addition of wastewater to wetlands includes suspended solids (SS) load.
The SS load varies according to efficiency of pre-treatment. Where the
long-term addition of wastewater has taken place, unconsolidated sediments
unlike those found in natural areas have been reported (Winchester 1981).
These sediments have been formed because the accumulation of SS exceeded the
rate of degradation and export. The SS load may influence benthic plant
communities and filtration capacities (Boto and Patrick 1978). Limits to
accumulation have not been determined. This build-up is more likely to be a
long-term than a short-term consideration, unless accumulation is excessive
in the short-term.
Aquaculture (hyacinth) systems
The hydraulic loading rates in aquaculture systems are limited by the
uptake rate of the plants involved and the containment basin characteristics.
The most efficient plant tested has been the water hyacinth (Eichhornia sp.)
320
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Table 8.1.1. Kydrologic Loading in Artificial and Natural Wetland Systems.
Range of
Systeni Observed Values Observations 1
Hydrologically Jpen
Wetlands
Strand-Mixed
Hardwoods
Strand-Cypress
Marsh
Hydrologically
Isolated Wetlands
Cypress Dome
Pocosins
Artificial
Wetlands
Aquaculture
0.11 - 9.81
2.3 - 13.0
1.5 - 9.6
1 - 13.7
2.3 - 2.4
0.037-13.0
Wide range of observed loading; system performance
limits not exceeded by these rates, site
specific factors important
Wide range of rates also observed, site specific
factors important
Studies indicated "slight" changes occurred at
observed rates
This range has shown minimal impact at this level;
greater rates could be possible with larger domes
Rational design criteria projected for pocosin-
wastewater system developed by CI^M Hill
This loading minimizes odor problems associated
with higher loadings
Observations derived from recent wetlands research concerning wastewater management.
Source: Claude ferry X Associates, Inc. 1982.
-------
8.1.1 Continued
and the majority of the data presented has been generated from hyacinth
systems. Loading rates of 240 to 3,570 m3/ha-day are reported for these
systems in the literature. For artificial systems receiving untreated
effluent, loadings have ranged from 240 to 680 m3/ha-day. Loading rates
considered as "reasonable" from field tests are presented in Table 8.1.1.
Few studies exist with nutrient removal as the principal objective.
Middlebrooks (1980) estimates that 500 m3/ha-day or less of secondary
effluent should provide effluent with <2 mg/1 of total nitrogen and 50
percent phosphorus reduction.
Most investigators recommend water depths of 0.9 meter or less. The
objective is to provide shallow depth so the suspended hyacinth roots can
penetrate through most of the water. Depths of 0.4 meter assure complete
wastewater contact with the root system.
Only one study has actually measured detention time utilizing dye
releases. Ratios of actual to theoretical detention times were reported to
be approximately 0.75 for long, narrow channels and 0.5 or less for more
circular basins ^nd systems adapted to water hyacinths. The values for
detention times shown on Table 8.1.2-e.
322
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8.0 RANGE OF KEY TECHNICAL FACTORS
8.1 Key Engineering Considerations
8.1.2 Water Quality Parameters
INFORMATION ON OBSERVED RANGES OF SHORT TERM NUTRIENT LOADINGS
AVAILABLE FOR SOME WETLANDS; INFORMATION ON OTHER WATER
QUALITY PARAMETERS SPARSE
A wide range of nutrient loadings has been reported for
natural wetlands along with one case of unacceptable
loading rate. Phosphorus presents a greater limitation
than does nitrogen (especially in the nitrate form).
Guidelines for DO, BOD and metals inputs are not well
developed. Temperature is an important consideration in
biological treatment processes. Hyacinth aquaculture is
capable of assimilating large quantities of TN and TP but
allowable metal and toxicant uptake is restricted in those
systems coupled with feed or energy production.
Natural Systems
Ranges for total nitrogen loading in cypress and mixed hardwood strands
have been reported from 0.004-0.36 kg/ha-day. Ranges of total phosphorus
have varied from 0.01-0.04 kg/ha-day. Cypress domes receiving 0.07 total
nitrogen (TN) and 0.05 total phosphorus (TP) kg/ha-day have been documented
without apparent adverse effects. A marsh receiving up to 0.31 TN and 0.17
TP kg/ha-day for two years was also not significantly disturbed. However,
Steward and Ornes (1975) reported that a marsh receiving 0.06 TP kg/ha-day
was significantly disturbed. These authors suggested that this marsh was
adapted to low nutrient conditions and was incapable of assimilating highly
elevated levels of phosphorus. In Table 8.1.2-a a range of observed TP and
TN loadings for natural and artificial systems are presented. The effect of
P-loading on P-removal is presented in Figure 8.1.2-a.
Metals may be removed by precipitation, absorption, and plant uptake in
natural systems. These limits, however, are not well described. The dangers
of bioaccumulation and biomagnification should be recognized when metal or
toxicants are introduced into wetlands. The great number of toxic compounds
in the environment permit few generalizations with regard to their limiting
effects in wetlands application of wastewater. The effects, distribution and
degradation of toxic compounds in wetlands is best dealt with on a
case-by-case basis. The information provided in Table 8.1.2-c indicates the
heavy metal uptake potential of several common wetland plants. Artificial
wetlands may be used to remove metals from solution (Table 8.1.2-d).
The pH of most domestic wastewater is well buffered near neutral pH
(7.0). Most wetlands have a lower, more acidic pH (3.5-5.5). Concern has
been expressed regarding the alteration of this endemic pH, especially with
acidophilus plants. Christiansen et al. (1978) expressed concern over
Sphagnum sp. and their potential elimination resulting from pH alteration.
323
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UJ
ro
Table 8 1.2-a. Nutrient Loading in Artificial
System
Range of
Observed Values
kg/ha-day
and Natural Wetland Systems.
Observations
Hydrolo< Ically Open
Wetland; TP
Strand-r ixed
Hardwoocs
Marsh-Organic
Marsh-Mileral
Hydrologically
Isolated Wetlands
Cypress )ome
Pocosins
Artlficliil
Wetlands
Hyacinth;
°-05
0.5-3.03
TN
0.01-0.04 .004-0.07
Strand-Cypress 0.02-0.03 0.36
0.06-0.17 0.31
0.06
0.07
0.05
0.15-0.79
No gross changes noted in systems receiving
these levels
No gross changes noted in systems receiving
these levels
"Slight" changes at observed levels
Observed value caused apparent harm; recommend
order of magnitude safety factor or improve
management of application
Small changes at observed levels
Proposed in CH2M Hill study
High rate potential; proposed range depends on
management objective; facilities plan
Source: Claude Terry & Associates, Inc. 1982.
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OJ
INJ
cn
rganic
Loading
, . Rate
Location
Williamson Creek,TX
Phase I (109 m3/d) 43
Phase II (109 m3/d)
Coral Springs, FL
National Space
Technology Labs
89
31
26
Nutrient Loading Rates
to First Unit
'ercent
Nutrient
.Removal
15.3
18.5
19.5
2.9
4.8
0.9
70 -
64
96 67
72 57
Single Basin, surface
area = 0.0585 ha
Single Basin, surface
area = 0.0585 ha
Five Basins in Series
Total surface area =
0.52 ha
Single Basin Receiving Raw
Wastewater, surface area
= 2 ha
Source: Middlebrooks 1980.
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Table 8.1.2-c. Typical Concentrations of Metals in Aquatic Plants Grown
in Metals Contaminated Environments.
Metals Concentrations (ppm of dry wt.)
Plant
Water hyacinth
Duckweed
Cattail
Bui rush
Cd
10
17
-
--
Pb
45
120
9
--
Cr
12
65
8
12
Cu
48
79
37
7
Ni
15
26
8
5
Zn
50
110
30
50
Source: Stowell et al. 1980
Table 8.1.2-d. Influent and Effluent Concentrations of Metals from a
Cattail Marsh Receiving Comminuted Wastewater with 15
Days Residence Time.
Metal
Zn
Cr
Cu
Influent
(mg/1)
1.3
0.05
0.07
Effluent
(mg/1)
0.2
0.01
0.03
Source: Stowell et al. 1980.
326
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Table 8.1.2-e.
Key Factor
Documented Values or Ranges for Various Key Factors for
Aquaculture Systems.
Aquaculture (Hyacinth) Systems
Receiving Untreated^
Primary, or Lagoon Effluent
Receiving
Secondary Effluent
Hydraulic loading,
cm per week or
or m3/ha/day
Water depth,
meters
200 or less
(Middlebrooks)
1.2 to 1.8
(3 Mississippi systems)
Wastewater detention 50 or more
time, days (2 MS systems)
(calculated)
Maximum basin
size, ha
# basins
Costs
Temperature, °C
BOD5 loadings,
kg/ha/day
Evapotranspiration
losses
Hydraulic loading,
cm per week
or m3/ha/day
0.4
(Dinges 1979)
28 to 30 C for maximum
productivity (O'Brien 1980)
30 or less
(Middlebrooks)
3.2 to 5.7 times greater than
for open water (O'Brien 1980)
0.33-1.0
Wastewater detention -
time via surface streams, days
0.8
(Bouter: Coral Springs, FL)
2,000 or less
(Middlebrooks)
0.4
(2 Florida systems)
6 or more
(Coral Springs, FL)
0.4
(Dinges 1979)
3 in series
$165,000 construction
cost for 0.1 mgd
system (Bowker 1982)
0.037-13
100 or less'
30 or more3
Middlebrooks. 1980.
•'•Two MS systems receive untreated effluent with five-day BOD concentrations
of 90 to 160 mg/1.
2Hydraulic loadings of 500 m3/ha-day or less of sec. effl. are estimated to
be needed to obtain TN <2 mg/1 (Middlebrooks 1980).
3For flow-through cypress domes in Florida (Boyle Engr. Corp. 1981). The
range for detention time in the Jasper, FL system is reported to be from 4
to over 60 days depending upon storm events.
327
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8.1.2 Continued
The effects of pH alteration on wetlands are not well documented. Ex-
treme pH elevations (>9.0) outside the natural range (3.5-8.0) are expected
to have impacts on nutrient availability and result in potentially harmful
effects on invertebrates and fish. These impacts would be highly spec-
ies-specific. High salt contents in effluents have been suspected of causing
severe disturbances in at least two freshwater wetlands, but critical concen-
trations and other documentation are not yet available.
The dissolved oxygen regime may interfere with degradation and respira-
tion processes in sediments; however, no adverse effects have been reported
for wetlands. The DO levels vary diurnally and seasonally ranging from <1.0
to supersaturation. Many wetland components are adapted to low and periodi-
cally anoxic (no D.O.) regimes. The magnitude of DO fluctuation is expected
to increase with wastewater addition, but its effects are unknown.
A Florida cypress dome receiving secondary sewage tolerated short-term
values of 25 mg/1 of BOD without appreciable harm. Control domes averaged 5
mg/1 BOD. The limits and effects of BOD loadings in wetlands within Region
IV is not well documented. Stowell et al. (1980) studied the relationship
between BOD loading and BOD removal in natural and artificial wetlands. From
their studies (Figures 8.1.2-b,c,d), it appears that greater than 50 percent
removal can be anticipated from the use of some wetland systems.
Wetlands modify local climatic factors (Gannon et al. 1979), and the
effects of wastewater addition to this wetland function are unknown. Sea-
sonal fluctuations may limit the temperature-dependent wastewater renovation
processes in wetlands. For those wetlands in the northern sections of Region
IV, essential biological processes are slowed down in the winter, resulting
in build-up of nitrites and lowering denitrification rates. Microbial res-
piration, important in the breakdown of organic matter, is impeded. Nutrient
uptake by plants as a removal mechanism in winter is slowed down or elimi-
nated. In southern sections of Region IV, duckweed is important in nutrient
cycling during the winter when trees, shrubs and grasses are respiring at low
rates. Temperature also affects chemical processes of nutrient removal
(precipitation, absorption)/ The limits to the seasonality of wastewater
renovation by wetlands in Region IV have not been documented but may be
limited in some areas to warmer months. Higher water levels can affect
temperature moderation in marshes that may protect vegetation from marginal
freezes or droughts.
Aquaculture
Hyacinths can thrive in municipal wastewater and in mixtures of certain
industrial and municipal effluents. See Table 8.1.2-b and c for nutrient
loading rates and removal efficiencies reported in the literature. Removal
of nutrients/metals/toxic organics is obtainable, but such removal can be a
disadvantage if the hyacinths are to be utilized for feed or energy
production. Some data are available concerning metals associated with
aquaculture systems (Table 8.1.2-c,d) but conclusive statements are not yet
available regarding removal efficiencies.
328
-------
8.1.2 Continued
Two Mississippi systems accepting untreated wastewater (influent five-day
bUU of BO to 160 mg/1) have been utilizing loading rates of 26 and 44
kg/ha-day, respectively. The system operating at 26 kg/ha-day reportedly
operated without significant odors whereas the system operating at 44
kg/ha-day developed odors at night. Loading rates for systems receiving
secondary effluent range from 31 to 197 kg/ha-day. Only two such systems
have provided significant amounts of data.
Hyacinth aquaculture operates at maximum efficiency between 28-30°C (see
Table 8.1.1-e). The use of plants with lower temperature optima should be
investigated in northern areas of Region IV.
329
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20
i .5
UJ
K
§
S
10
8i 5
O
DATA FROM 8 DIFFERENT STUDIES
o Hyacinths
• Marsh
5 10 15 20
PHOSPHORUS LOADING (kg/ha-d)
Figure 8.1.2-a. Effect of phosphorus loading on phosphorus removal
Source: Stowell et al. 1980.
330
-------
40
30
S
l
ui
20
10
DATA FROM 17 DIFFERENT STUDIES
50 100 ISO
INFLUENT BOD (mg/L)
200
Figure 8.1.2-b. Effluent BOD concentrations (aquaculture systems).
Source: Stowell et al. 1980.
331
-------
250
DATA FROM 16 DIFFERENT STUDIES
• Primary
o Secondary
50 100 150
BOD5 LOADING (kg/ha-d)
200
250
Figure 8.1.2-c. Effect of BOD loading on BOD removal
Source: Stowell et al. 1980.
332
-------
100
80
60
Q
id
§
40
20
DATA FROM 5 DIFFERENT STUDIES
20 40 60 80
BOD5 LOADING (kg/ha-d)
100
Figure 8.1.2-d. Effect of BOD loading on BOD removal (marsh and peatland
systems)
Source: Stowell et al. 1980.
333
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8.0 RANGE OF KEY TECHNICAL FACTORS
8.2 Key Environmental Management Parameters
8.2.1 Habitat and Wildlife
HABITAT ALTERATION AND CHANGES IN SPECIES COMPOSITION ARE CRITICAL
ISSUES IN WETLAND CONSERVATION EFFORTS
Wetlands serve as reservoirs for rare and endangered
species. The significant alteration of known or suspected
habitats of protected species should be avoided. Habitat
alteration and changes in species composition may occur as
a result of wastewater addition, but the extent and
significance of these changes are open to interpretation.
Natural Systems
Habitat alteration and species shifts are critical issues in wetland con-
servation efforts. The most basic changes in wetlands as a result of waste-
water addition are the increase in nutrient and hydrologic regimes. The more
these factors depart from the natural regimes, the greater the potential
impact to habitat and species composition both within wetlands and in down-
stream ecosystems which are closely linked to wetland processes and functions
(estuaries, etc.). For example, bottomland hardwoods are adapted to ex;treme-
ly high nutrient loading, and excess nutrients would likely have 'minimal
impact in this system. The plants and animals in bottomland hardwoods,
however, are sensitive to alterations in the natural pattern of hydrologic
fluctuations and might suffer significant adverse impacts. On the other
hand, marshes and some cypress ecosystems are adapted to nearly continuous
inundation and low nutrient regimes and impacts to wildlife might be less
severe. Concern has been expressed (Kuenzler 1982) that the increasing
eutrophication problems in the upper estuaries of North Carolina result from
the remaining wetlands (30 percent of original acreage left) no longer being
able to filter-out increasing nutrient loadings from disturbed watershed
runoff. Logically, increased nutrient loadings from wastewater additions may
further exacerbate the eutrophication problem in the estuaries.
Shifts in nutrient regimes and habitats affect community dynamics. In
cypress domes with sewage additions, a shift from tadpoles to surface feeding
herbivores and detritus feeders was observed (Davis 1976), and a replacement
of herons by more passerine birds was hypothesized. Similar effects on
trophic levels may occur in other wetlands receiving sewage, but this has not
been documented. The limitations these effects may place on wastewater
addition to wetlands are basically open-ended questions. Thus, the known or
suspected presence of a protected species may preclude the use of certain
wetlands for wastewater recycling.
Aquaculture Systems
Habitat and wildlife considerations are not specifically applicable to
aquaculture systems, except in the case of multiple-use artificial systems
that have been developed to create habitat for water fowl and other wildlife.
This is a potentially positive aspect of creating artificial wetlands. Exist-
ing observations from the Mountain View system in California indicate a high
degree of success in creating a habitat for water fowl.
334
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8.0 RANGE OF KEY TECHNICAL FACTORS
8.2 Key Environmental Management Parameters
8.2.2 Public Health Considerations
EFFECTS OF BACTERIA AND VIRUS ON WETLAND VALUES AND
GROUNDWATER SHOULD BE CONSIDERED
The public health concerns of wastewater recycling in
wetlands include the effect on groundwater and export of
waterborne disease in surface waters. Enzootic diseases
do not appear to be amplified. Other key public health
factors are noted, but their relevance to the limitations
of this practice are unknown.
Several key factors exist with regard to the public health aspects of
wastewater recycling in wetland areas. The protection of groundwater
resources from contamination is of primary concern. For example, the soil
profiles beneath several Florida wetlands act as effective although not total
barriers against groundwater contamination from surface-applied wastewaters.
The key soil constituents were clays, sand and organic matter. The ability
of other wetland soils beneath Region IV wetlands to provide similar barriers
against groundwater contamination is unknown.
Another key factor is the fate of potentially hazardous microorganisms in
surface waters of wetlands and in adjacent water bodies. Longer detention
times within wetlands allows for more sedimentation and great inactivation of
enteric microorganisms. This detention time subsequently lowers the prob-
ability of export of vectors of waterborne disease. The amount of reduction
required to meet water quality standards depends on the pre-treatment effi-
ciency. The potential vectorborne disease and nuisance problems of waste-
water disposal in wetlands have not been fully examined. Results from
studies on impacts of wastewater on enzootic encephalitis vectors in Florida
indicated no problem existed. The modern relationship of other such vectored
diseases (malaria, tularemia) has not been studied.
Other key public health factors in wetlands disposal systems include: 1)
the unknowns regarding long-term effectiveness and limitation of each Region
IV wetland type in removing, treating or confining pathogens (or other
hazardous material), 2) food-chain effects of bioaccumulation or biomag-
nification, 3) effects of variable seasonal factors (rainfall, temperature,
etc.) on treatment efficiency, 4) implications of restricted future use of
affected wetlands 5) whether chlorination of wastewater previous to discharge
to wetlands is wise in view of hazards presented by low-molecular weight
chlorinated hydrocarbons resulting from contact of chlorine with organics
found in water (characteristic of wetlands) and 6) the presence of poten-
tially toxic unionized ammonia and nitrite. Many of these concerns are rele-
vant to surface water discharges as well. Research is being performed to
address some of these concerns.
335
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Awwwns
6 NOI133S
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9.0 SUMMARY
KEY TECHNICAL AND INSTITUTIONAL ISSUES MUST BE RESOLVED
TO ASSESS WETLANDS DISPOSAL FEASIBILITY
The implementation of wetlands disposal systems is
dependent on the resolution of key technical and
institutional considerations. This section identifies and
discusses these considerations and provides a basis for
evaluating the feasibility of using wetlands for waste-
water management in Region IV.
This section is intended to focus on the technical and institutional
considerations that may act independently or jointly to influence the
feasibility of using wetlands as a wastewater management alternative. The
importance of many of these key elements has regional significance while
others are of only state or local consequence.
The technical considerations include general elements that may limit the
feasibility of wetland discharge in a number of ways. Adequate knowledge may
not exist on a key technical element and the resulting uncertainties may
produce unacceptable risks. From an engineering or environmental standpoint,
existing knowledge may be adequate to disqualify a wetland from rational
utilization.
The institutional issues examined in this section address problems in
permitting, legal issues and environmental regulations that may impede the
implementation of wetlands disposal systems. Agency conflicts are discussed
as potential problems. Inappropriate regulatory policy results in inadequate
or inconsistent resolution of the wetlands disposal issue.
Issues of Interest
t What are the key engineering elements which affect the use of wetlands
disposal systems?
• What are the areas of scientific knowledge required for predicting and
mitigating the impacts of wastewater on wetlands?
• Do institutional mechanisms adequately address the wetlands disposal
issue?
• What types of conflicts exist in permitting wastewater discharge to
wetlands?
• What institutional considerations are most likely to impede the
utilization of wetlands in a wastewater management scheme?
337
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9.0 SUMMARY
9.1. Critical Technical Considerations
WETLANDS HAVE DEMONSTRATED TECHNICAL POTENTIAL AS A WASTEWATER
MANAGEMENT TOOL BUT IMPAIRMENT OF NATURAL FUNCTIONS
IS MAJOR CONCERN
Accelerated research efforts in applied wetland sciences
have greatly Increased our knowledge of wetlands and their
potential use as wastewater management systems. Critical
technical considerations are presented in this section
from both a general and site specific perspective. Many
technical elements must be examined to ensure against loss
of wetland value from wastewater additions.
The immense ecological importance, variety and complexity associated with
natural wetlands are highlighted by the results of studies within Region IV
and elsewhere. Despite certain limitations, large quantities of scientific
information are available on wetland systems in the southeast. This infor-
mation has also provided an increased understanding of the processes and
problems associated with natural and artificial wetlands and their use in
wastewater management. From this information it is possible to identify key
elements critical to the proper maintenance and functioning of wetlands
receiving wastewater. The assessment of these elements on both a general and
wetland specific perspective provides a basis for discussing the technical
feasibility of using wetlands for wastewater recycling.
The difficulty in summarizing the technical elements that must be con-
sidered in evaluating wetlands disposal systems lies in the diversity of
wetland types and limits in existing knowledge. The approach taken in
section 9.1.1 relies on a comprehensive list of general technical factors
that control the feasibility or desirability of a wetlands discharge. They
are intended as guidelines to assist in the formulation of elements relevant
to evaluating a potential or existing wetlands discharge. These elements
include but are not limited to geomorphology, vegetation, hydrology, water
quality, wildlife values and engineering considerations. Included in this
section are more detailed issues associated with each of these topics and a
brief explanation of why they are important and what functional role these
issues take in maintaining the value of wetland areas. This analysis is not
meant to imply that all these factors are equally applicable to all wetlands.
In fact, the site specific nature of wetland characteristics causes the
opposite to be true.
The translation of these general factors to key issues relevant to
specific wetland types is exemplified in section 9.1.2. These key issues
were identified based on the relative degree of importance in maintaining
wetland values and the status of knowledge of these issues in reference to
specific wetland types. Those elements with a high degree of importance and
a low status of knowledge are highlighted in the discussion of selected
wetland types. A matrix was developed to assess these general elements on a
wetland specific basis and is presented in the Appendix to this report.
338
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9.0 SUMMARY
9.1. Critical Technical Considerations
9.1.1 General Elements Critical to Evaluating Wetland Discharges
DELINEATION OF WETLAND VALUES AND DEVELOPMENT OF ACCEPTABLE POLLUTANT
AND HYDROLOGIC LOADINGS ARE IMPORTANT DETERMINANTS
A generalized perspective helps identify the range of
considerations that may limit the use of wetlands for
wastewater management. The discussion of hydrology
vegetation, wildlife values, engineering considerations
and other parameters provides a technical orientation and
guidance for the evaluation of wetlands receiving
WQ S16Wd c f* r*.
wastewater.
of wetlands
hydrology geomorphology, water quality, trtldHfe value" enqineerina
™™ ' *° °ther SyStemS- The mtSetS? "of th'e
esd sh
thatmaint,inh tconta1n«d in Table 9-1-1 are the fundamental areas
that maintain the structure and function of wetland areas. Within each of
these topics specific issues are identified salient to the management o?
wastewater applet ion to wetlands. The geomorphology of wetlands areas
encompass several variables including physical shape, soils and "geology of
wet ands watersheds. These basic properties, in turn, influence other
wetland properties and processes. Soils, for example, inf uence nutMent ^ and
hydrologic retention capacity. Hydrology is the key requlator for manv
wetland processes. Components of the water budget need ? te e aluated both
eSand n °rder t0 estimate th
P«rt. the assirtltive capacity
is presented in Table 9.1.1.
339
-------
Table 9.1.1. Area^ of Concern of Key Wetland Characteristics.
Topic
Areas of Importance
Functional Role and Importance
Geomorphology
-Geology
-Soils
Karstic Areas
Drainage Basin Characteristics
form
Drainage Basin Characteristics
types
Organic Soils
Mineral Soils
-Physical None
Characteristics
Vegetation
-Plant
Ecology
-Vegetative
types
-Succession
-Productivity
-Rare and
endangered
Material Cycling
Adaptations
Ti re Frequency
Jominant vegetation
jubdominant vegetation
Community equilibrium
Rate of production and
respiration
I'elicate, unique and irre-
placeable ecosystems
Lelicate, unique and irre-
placeable species
Groundwater interactions in limestone areas uncertain; pose potential benefits
and hazards
Areas of high topographic relief create potential for strong flood
pulses resulting in undesirable flushing of effluent out of wetland
without treatment
Carolina Bay and other formations have intrinsic scientific, cultural
and hydrologic values which may be threatened by wastewater application
Nutrient retention potential low, permeability may be too low
High nutrient retention potential, permeability may be low
Clay pan impermeability protects groundwater resources but may impede
surface water loading capacity
Manifested in other parameters (geology, hydrology, etc.)
General ecosystem functioning; wastewater addition may possibly augment
or imbalance
Plants specialize to grow and successfully compete in wetlands; modifi-
cations in nutrient and hydrologic regimes may alter species assemblages
Fire is important in maintaining the character of some wetlands; con-
tinuous wastewater application may prevent necessary dry-down for fire to
occur
Essential in determining community structure and productivity, also habitat
value, and influences water quality, surface water flows
Important in filling and creating specialized ecological niches
Necessary to maintain a stable and productive ecosystem
Controls nutrient uptake and storage capacity; determines quality and
quantity of detritus, and influence evapotranspiration values. Diurnal
pattern may be of sufficient intensity to alter water quality parameters
of DO and pH
The location, range and inherent scientific and cultural values of these
ecotypes require that these qenetic pools are maintained intact and inplace
The location, range and inherent scientific and cultural values of these
species require that these genetic pools are maintained intact and inplace
-------
Table 9.1.1. Continued.
Topic
Areas of Importance
Functional Role and Importance
Hydrology
-Budget
Pr;cipitation Component
Grjundwater Component
Surface water/Runoff Component
-Inundation Frequency and Duration
-Infiltration Capacity of Vertical Water
Mo\ement
-Flooding Nutrient Import/Export
Effects
Buffer Capacity
-Evapotrans- None
piration
Water Quality
-Chemical Dissolved Oxygen
pH
Nutrients
Met.)I/Toxins/Refractory Organics
-Physical Turbidity/Suspended Solids
Limit loading rates of wastewater
Groundwater discharge area places limits on loading rates of wastewater.
Groundwater recharge area may prohibit wastewater application if effluent
quality is poor
Sources, rates and timing of inflow critical to maintaining wetland vegetation,
detrital sediment and nutrient loading
Outflow characteristics define seasonal pattern of surface water storages,
location of outflow may limit acceptability of wastewater application
Dominant force in shaping distribution and character of wetland vegetation.
Changes in catachment size and shape, antecedent moisture, and watershed
topography will alter flooding characteristics
Infiltration capacity important in limiting loading rates, treatment capacity
and efficiency
Major source of nutrients for some wetlands and downstream ecosystems
may be dependent on wetlands exports for nutrients and food supply
Wetlands have value as regional flood buffering devices, and aid in low-flow
augmentation. Wastewater addition may lower this hydrologic buffering capacity
Not important unless drastic ecosystem alteration takes place. Wastewater may
increase evapotranspiration
Plant and fish life tolerate low DO; but zero DO is detrimental
Controls type of microbial respiration and organic matter degradation
Some plants present (Sphagnum) depend on low pH. Nutrient release from
sediments is pH dependent. Wastewater addition increases pH, and carbonate
buffering capacity
Nutrient cycles need to be balanced for proper ecosystem production. Productivity
may he limited by nutrient availability. Nutrient exports by open wetland
ecosystems create important links to downstream ecosystems
Direct - acute and chronic effects from exposure to detrimental concentrations
Indirect - bioaccumulation
Important source of particulate organic matter. Sedimentation of these
particles provide basis for sediments, detrital food chain
Temperature
Effluent extends growing season in cooler climates, and nay promote frost damage
-------
Table 9.1.1. Continued.
Topic
Areas of Importance
Functional Role and Importance
-Biological Microbial Respiration
Public Health Vectors
Alrae blooms
Increase in macrophytes
Wildlife Values
-Habitat Edge Effect/Niche Separation
-Threatened Habitat loss - Species Mainte-
or Endan- temnce interfered with
gered Species
Engineering Considerations
-Evaluation/ Screening potential sites--
Site Selec- con>istency of selection
tion Proce- prooesss
dures
-Pre-treat-
ment Re-
qui rernents
-Hydrologic
Loading
-Catchment
Basin size/
Detenti on
Tine
-Depth
Des gn of wastewater treatment
fac lity
Syst em Capacity
System capacity—contact time
System capacity--method of
application
-Frequency Seasonal application
of Effluent Continuous application
Application
-Effluent Distribution Systems
Application
Methodology
Breakdown of organic matter, nutrient cycles
Maintain or increase reservoir of imported or endemic water or arthropod borne
disease
Odor, aesthetic, toxic producing nuisance
Short term, seasonal storage of nutrients, influences subcanopy
ecology in swamp forests
Maintains trophic levels productivity for ecological balance
Scientific and cultural values; maintains genetic diversity
Need to identify wetlands with disposal potential; eliminate those with
low potential, in a justifiable and rational manner
Reduce concentration of waste load to within a range of values acceptable
to wetlands assimilative capacity
Determines ultimate volumetric capacity of wetlands; Impacts vegetation
type and occurrence
Determines wetland capacity; places limits on "contact opportunity" for
degradation and assimilation of wastewater constituents
Adverse depths may cause harm to vegetation; reduce treatment efficiency and
limit ultimate capacity of system
Steady periodic and seasonal application of wastes to wetlands have differing
advantages which should be evaluated at each potential wetland discharge site
The use of single or multiple outfalls should be evaluated to minimize adverse
effects; sheet flow may optimize treatment efficiency; flow pattern and path
to outflow also important function
-------
9.1.1 Continued
The quality of water within wetlands and discharging from wetlands is of
concern in wetlands utilized for wastewater management. The chemical,
physical and biological processes that impact water quality may produce
undesirable changes within wetlands or have adverse impacts on adjacent water
bodies. Uncertainties about the fate and potential effects of toxins and
pathogens contained in wastewater are of concern. The removal of these and
other wastewater constituents, the maintenance of wetland habitat and
valuable linkages to other ecosystems are the principal objectives of the
engineering considerations listed in Table 9.1.1. Linkage of wetlands to
other ecosystems is important. In many watersheds, the removal of nutrients
and sediments from floodwaters by wetlands is crucial to maintaining water
quality of lakes streams and estuaries. The engineering considerations
involved with the design of distribution systems and evaluating pollutant and
hydrologic loading capacity are among the most difficult issues to address,
but the technology is developing in this area.
The evaluation of these fundamental components of wetlands outlined in
this section should be approached from an integrative perspective. It is
evident that not all these factors have an equal role in determining the
feasibility of a wetlands discharge. The evaluation of these factors in
reference to a particular wetland or wetland type is needed to bring meaning
to these parameters. This type of evaluation will highlight the diversity of
wetland types and their relative compatability with wastewater applications.
343
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9.0 SUMMARY
9.1. Critical Technical Considerations
9.1.2 Site Specific Elements Critical to Uetlands Discharges
EXCLUSIVITY OF WETLAND TYPES REQUIRES SITE SPECIFIC ANALYSES
Major wetland types within Region IV are assessed with
regard to their potential use for wastewater management.
Hydrologically open systems are endowed with attributes
useful in wastewater treatment; hydrologically isolated
systems provide greater control over treatment parameters.
Maintenance of habitat for wildlife and retention of waste-
water constituents are highlighted as areas of concern in
all wetland types.
The purpose of this section is to extend the concepts developed in 9.1.1
and apply them to specific wetland types found within Region IV. The goal of
these assessments is to identify those key elements that are most critical in
the maintenance of the value and function of wetlands receiving wastewater.
The elements outlined in Section 9.1.1 highlight the sensitive technical
issues important to specific wetland types and their use as wastewater man-
agement alternatives. Specific elements are assessed on the basis of their
degree of importance and status of knowledge. These two parameters were
rated high, medium, or low for each key factor identified in Section 9.1.1.
The ratings for each factor as they pertain to the selected wetland types are
presented in the Appendix. Those key factors rated as having a high degree
of importance and a low status of knowledge were selected as those most
likely to become primary determinants in controlling the feasibility or
desirability of initiating a wetlands discharge. Conversely, those technical
elements rated with a low degree of importance and high degree of knowledge
are of less generic concern, but may take on high local values and
importance. Table 9.1.2 summarizes the most important considerations germane
to each wetland group.
Wetland types highlighted in this report are broadly grouped as either
hydrologically open or hydrologically isolated systems (Table 9.1.2), as
discussed in section 2.3. and are further typified by characteristic vege-
tation. The corresponding National Wetlands Inventory classification for the
wetlands types listed in Table 9.1.2 may be found by consulting the class-
ification matrix developed for this EIS (Table 2.3).
Among the hydrologically isolated systems, cypress domes have received
the most attention in researching the use of wetlands as wastewater manage-
ment tools. However, several areas of concern persist (for example, ground-
water contamination and proximity to developed areas) that may limit the use
of cypress domes for wastewater management. Other hydrologically isolated
wetlands possess significant ecological uncertainties that may preclude their
use without cautious appraisal of these potentially limiting parameters. For
example, the presence of Threatened and Endangered Species, the effects of pH
elevation in acid bogs, material cycling and retention of wastewater consti-
tuents are elements that are of critical concern in several of the hydro-
logically isolated systems highlighted in Table 9.1.2. These wetlands in
344
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9.1.2 Continued
general, being less "connected" to flows of nutrients and. water than are
hydrologically open systems, are more likely to be altered by the addition of
wastewater (Day 1980).
Hydrologically open wetlands (riverine swamps, bottomland hardwoods,
strands, etc.) are more dynamic and transitory systems, responding rapidly to
changes in water levels. These systems are also amenable to naturally high
nutrient loadings. The addition of wastewater to these systems have
potentially adverse implications to downstream ecosystems inextricably linked
to the maintenance of wetlands buffering and cleansing processes. The high
recreation values and hydrologic uncertainties of these systems are elements
that must be adequately considered in assessing the use of these systems for
wastewater discharges.
Nonetheless, the structure of riverine wetlands endows them with certain
characteristics valuable in wastewater disposal including but not limited to:
(1) sheet flow which maximizes exposure of effluent to nutrient exchange and
renovation mechanisms, (2) adaptations to high levels of nutrient loadings,
(3) potential tor nitrification and denitrification processes, (4) storage of
nutrients in biomass, (5) high rates of nutrient cycling and (6) proximity to
existing point sources of nutrient addition. However, considerations such as
potential food webb accumulation of toxic substances and irregular hydrologic
regimes that may minimize pollutant dissipation or retention and lead to
overloaded downstream ecosystems must be recognized.
This brief assessment of wetland types and their potential use in waste-
water management has highlighted key technical elements which should be
considered when evaluating a wetlands discharge. The inherent diversity and
variety of wetland types suggests that a site specific evaluation of wetlands
will produce a set of unique and separate factors of concern for each wetland
evaluated. The exclusivity of wetlands is the overriding factor that pre-
vents greater resolution of site specific varibles that will ultimately
determine the acceptability or feasibility of a wetlands discharge.
345
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Table 9.1.2. Areas of High Importance in Selected Region IV Wetlands.
Systems
Areas of High Importance
Hydrologically Isolated
Cypress Dome
Carolina
Pocosins
Bays,
Long term maintenance of dominant vegetation. Pre-
servation of ecotype in regions where ecotype is
uncommon. Applicability of established wastewater
management techniques to domes other than those
studied. Soil structure relative to retention capacity
of wastewater constituents. Proximity to developed
areas. The following areas of high importance are
of special concern because of the low status of
knowledge:
o Groundwater contamination
o Wildlife values
As habitats subject to developmental pressures,
great concern over preserving the integrity of
these ecosystems including habitat, recreational
and wildlife values, threatened and endangered
species, and alteration of successional trends.
Hydrologic characteristics and soil types vary
throughout, resulting in uncertainties in nutrient
retention capabilities. Effects and/or limits of
other pollutant loadings (bacterial, metals, toxin)
are not well quantified and effects of increased
hydrologic loadings are not well studied. The
following areas of high importance are of special
concern because of the low status of knowledge:
o Rare and endangered ecotypes
o Threatened and Endangered Species
o Underlying geology
o Material cycling
o Sub-dominant vegetation
o Effects of pH
Marshes, wet meadows, Wide variety of marsh types indicate need for high
savannahs, wet
prai ries
degree of site specificity in planning wastewater
disposal. Hydrologic characteristics, soil types
and vegetative cover influence capacity to assim-
ilate and adapt to hydrologic and pollutant load-
ings. Species shifts of macrophytes may be of con-
cern. High wildlife and recreational values must
be preserved. Information from artificial wetlands
created for wastewater management may increase our
understanding and help alleviate these uncertain-
ties. The following areas of high importance are
of special concern because of the low status of
knowledge:
346
-------
Table 9.1.2. Continued
Systems
Areas of High Importance
o
o
o
o
o
o
o
o
Material cycling
Vegetation composition and succession
Rare and endangered ecotypes
Hydrological characteristics
Effects of pH alteration
Nutrient retention
Immobilization of metals, pathogens, toxins
Threatened and Endangered Species
White Cedar Bogs
Hydrologically Open
Bottomland Hardwood
Forests
Cypress and Mixed
Hardwood Strands
Many unknowns; primary concern over protection of
unique and rare ecosystems may preclude likelihood
of utilization in a wastewater management plan.
Effects of increasing ambient pH of concern.
Inadequate knowledge of ecosystem structure and
function. Preservation of wildlife and threatened
and endangered species necessary. The following
areas of high importance are of special concern
because of the low status of knowledge:
o
o
o
o
o
o
o
o
o
Rare and endangered ecotypes
Material cycling
Soils
Habitat alteration
Succession, productivity
Threatened and Endangered Species
Hydrologic characteristics
Nutrient retention
Effect of pH alteration
Effects of alteration of hydrologic regime on vege-
tation density and species composition, habitat
maintenance. Ability of ecosystem to adapt to in-
creased pollutant and hydrologic loading. Damages
to hardwoods may be more difficult to reverse than
damages to vegetation with short life cycles. Con-
cern over nutrient retention or washout during
hydrologic surges. Preservation of recreational
values. Linkage with other ecosystems is very
important. Groundwater interaction uncertain. The
following areas of high importance are of special
concern because of the low status of knowledge:
o Material cycling
o Interactions with groundwater
o Nutrient and sediment removal from floodwaters
Retention of wastewater constituents difficult to
predict. Hydrologically complex and variable. Man-
agement of wastewater flows critical to success of
347
-------
Table 9.1.2. Continued
Systems
Areas of High Importance
habitat maintenance and functional elements of eco-
system. Effects of wastewater addition studied in
Florida, but unknown if similar effects will be
found elsewhere. Difficulty in determining effects
on ecosystems linked to strand ecosystems. Rela-
tive importance of these variables is also site
specific. The following areas of high importance
are of special concern because of the low status or
knowledge:
Riverine,
Lacustrine
(Lake) Wetlands
Freshwater Tidal
Wetlands
o
o
o
o
o
Material cycling
Interactions with groundwater
Linkages with other systems
Recreational and wildlife values
Threatened and Endangered Species
Potential impacts on adjacent ecosystems relate to
retention of wastewater constituents. Hydrologic
interaction between wetland and adjacent systems
needs clarification. Short circuiting of waste-
water flow through marsh potential area of concern.
Wildlife and recreational values must be maintained
or improved. The following areas of high impor-
tance are of special concern because of the low
status of knowledge:
Hydrologic characteristics
Interactions/linkages with other systems
Retention of wastewater constituents.
o
o
The influences of drainage basin characteristics and
orientation of the wetland on nutrient and sediment
retention during peak flows are critical. Reten-
tion of wastewater constituents, immobilization ot
toxins, pathogens, metals within wetland site is
important. Linkages with adjacent systems are cri-
tical, especially for maintaining estuanne water
quality and quantity. High wildlife and recrea-
tional values must be maintained. The following
areas of high importance are of special concern
because of the low status of knowledge:
o Linkages with estuaries
o Wildlife, Threatened and Endangered Species
o Hydrologic uncertainties
o Turbidity
348
-------
Table 9.1.2. Continued
Systems
Areas of High Importance
Bogue, slough,
Oxbow wetlands
Changing drainage basin characteristics have degraded
many of these habitats. Wastewater additions may
exacerbate this problem. Wildlife, eutrophication
problems must be mitigated. Hydrologic characteris-
tics are uncertain. Retention or fate of major
wastewater constituents is unstudied. The follow-
ing areas of high importance are of special concern
because of the low status of knowledge:
o Preservation of threatened ecosystem
o Groundwater interactions
o Nutrients, retention of other wastewater
constitutents
o Linkages with other ecosystems
349
-------
9.0 SUMMARY
9.2 Critical Institutional Considerations
INSTITUTIONAL CONSTRAINTS COULD LIMIT IMPLEMENTATION
OF WETLAND DISCHARGES
Coordination between local, state and federal agencies is
essential in order to avoid conflicts concerning wetlands
protection and use and to establish adequate wastewater
discharge permitting procedures. The issue of ownership
also needs to be settled to avoid legal problems associat-
ed with the potential infringement on private property
rights.
Institutional constraints and problems can severely limit the ability to
implement concepts and technologies. Critical institutional considerations
concerning the use of wetlands for wastewater disposal include regulatory
policies concerning wetlands protection and use, ownership and proprietary
rights of private wetlands, and the various regulations and policies
associated with the NPDES Permit Program.
An understanding of wetland functions and values must form the basis for
any resolution of potential institutional conflicts or problems. Priorities
based on water quality and resource management goals will be needed to settle
potential conflicts between wetlands protection and use. Ownership require-
ments will need to be based on technical considerations as they relate to
assimilative capacity and potential type and extent of impact. Finally,
agreements must be reached among state agencies and among local , state and
federal agencies concerning the circumstances under which wetland discharges
will be permitted and the methodologies used for establishing permit
conditions. In this way inequities concerning wetlands use can be avoided
while maintaining important wetland functions and values.
The following three sections elaborate these critical institutional con-
siderations.
350
-------
9.0 SUMMARY
9.2 Critical Institutional Considerations
9.2.1 Wetlands Protection/Use
POTENTIAL CONFLICTS EXIST ON SEVERAL INSTITUTIONAL LEVELS
Potential conflicts concerning the protection and use of
wetlands exist among state agencies, among federal
agencies, and among local, state and federal agencies.
Additional clarification of wetland values and the suit-
ability of multiple-use concepts is needed before wetlands
disposal can be widely implemented. The restoration of
wetlands using wastewater effluent may serve the dual
purpose of wetlands protection and use.
Potential conflicts on several institutional levels relate to the
question of whether wetlands used for wastewater disposal can also be used
for other purposes. Although the concept of multiple-use management has long
been accepted and practiced in many forested areas, the applicability of this
concept to wetland ecosystems is untested, especially in relation to waste-
water disposal. Florida, for example, requires wetlands used for wastewater
disposal to be posted to restrict public access. This requirement could
cause conflicts between agencies concerned with fish and wildlife management
for public recreation and those agencies concerned with permitting wastewater
discharges. These potential conflicts exist on both the state and federal
levels when wetlands protection and use must be balanced.
Most wetland protection efforts relate to Section 404 Dredge or Fill
Permits administered by the Corps of Engineers (COE). State agency review,
either as part of the water quality certification process (Section 401
Certification) or in conjunction with state permitting programs, is usually
afforded to Section 404 Permits. Additional federal review is accorded the
U.S. Fish and Wildlife Service (FWS) and the U.S. Environmental Protection
Agency (EPA). Although Section 404 Permits may not be associated with all
wetland discharges, the overall policy towards wetlands protection has been
established by most review agencies and will likely carry over to the review
of NPUES permits. Requirements restricting public access in wetland disposal
areas may conflict with the legislative and policy mandates of review
agencies and inhibit widespread implementation of wetlands disposal.
Specific state legislation relating to wetlands protection has only been
enacted in response to coastal zone management in EPA Region IV. Georgia and
Mississippi have enacted specific coastal wetlands protection laws. The
other coastal states in the region, North Carolina, South Carolina, Florida
and Alabama, have enacted general coastal zone management laws which
indirectly protect coastal wetlands. No state in EPA Region IV has enacted
legislation specifically concerned with inland wetlands. The emphasis on
coastal wetlands is most likely the result of the federal impetus and funding
associated with the federal Coastal Zone Management Act of 1972 (PL 92-583,
as amended).
351
-------
9.2.1 Continued
All states in EPA Region IV have state level agencies responsible for the
management of fish and wildlife resources. The general mandate of most of
these agencies is the protection and management of fish and wildlife
resources relating to hunting and fishing interests, the primary source of
most state revenues available for fish and wildlife management. State man-
agement programs often involve the acquisition and/or management of wetland
areas for fish and wildlife habitats. If the use of wetlands for wastewater
disposal impedes their use for hunting and fishing, interagency conflicts may
anse. Similar conflicts have been recognized between the FWS and EPA and
have been addressed at both regional and national levels.
The resolution of these potential policy conflicts will require an under-
standing of wetland functions and values. The use of certain wetlands for
wastewater disposal may not necessarily infringe upon the value of that wet-
land for wildlife habitat. However, consumption of fish or wildlife from
wetland disposal areas may be prohibited and may limit the value of that
wetland for certain recreational purposes. Additional consideration must be
accorded to migratory species, especially waterfowl, which may spread
potential public health impacts far from the area of discharge. Timber
production is another wetland value which may be reduced with wastewater
disposal and will need to be assessed before wetland discharges are
permitted.
Not all wetland disposal projects involve a trade-off between protection
and use. The restoration of damaged wetland areas through the application of
wastewater effluent may serve the dual purpose of preserving valuable wetland
habitat and functions while also providing a means of wastewater disposal.
To date, most wetland restoration efforts have focused on tidal marshes and
have primarily involved revegetative efforts (Garbisch 1977). Commonly
recognized purposes of wetland restoration have included erosion protection,
creation of wildlife habitat, and the rehabilitation of dredge spoil areas.
Little research has been conducted on the rehabilitation of inland freshwater
wetlands except as a management tool for wildlife (Garbisch 1977). However,
two projects are under construction on Hilton Head Island, South Carolina,
and will involve the discharge of treated wastewater to wetland areas which
have been hydrologically altered by road construction and changed drainage
patterns. These and similar restoration projects will provide much needed
information concerning this potentially valuable method of wetlands restora-
tion and use.
In summary, existing state and federal laws provide for the protection of
wetlands primarily through the issuance of dredge or fill permits. In addi-
tion, channels of review have been established between state agencies, COE,
EPA and the FWS. Potential conflicts may arise when the use of wetlands for
wastewater disposal impede other uses for which review agencies have
responsibility. Potential inter-agency policy conflicts need to be resolved
through memoranda of understanding and the establishment of wetland use
priorities. The basis for conflict resolution will be an understanding of
wetland functions and values and the improvement of wetland multiple-use
management. Increased knowledge gained from current wetland restoration
projects involving wastewater discharges may resolve potential conflicts
concerning wetlands protection and use.
352
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9.0 SUMMARY
9.2 Critical Institutional Considerations
9.2.2 Ownership and Proprietary Rights
INFRINGEMENT ON PRIVATE PROPERTY RIGHTS IS A POTENTIAL PROBLEM
State and municipal governments may be potentially liable
for damages to private wetlands resulting from wastewater
discharges. This potential liability points out the need
for ownership or legal control of wetlands used for waste-
water disposal. Additional questions concerning necessary
extent of ownership and possible EPA funding are raised by
the issue of ownership.
Recent litigation in South Carolina involving a wetland discharge from
the town of Andrews has illustrated the need for legal control over wetlands
used for wastewater disposal. In this current court case, the State of South
Carolina is being sued for damages relating to the loss of timber in a
private wetland area. The plaintiff's contention is that the wastewater
discharge is the cause of his timber loss and the state is responsible since
it permitted the discharge. Subsequently, the state has amended its policy
and now requires ownership or some other form of legal control before a wet-
land discharge will be permitted. Florida is the only other state which has
such explicit requirements. Similar policies may need to be adopted in other
states before increased implementation of wetland discharges results in legal
problems.
In conjunction with the ownership issue, the required extent of ownership
and the eligibility for EPA funding need to be clarified. Investigations
will probably be needed on a case-by-case basis to determine the extent of
the area which may be potentially affected by wastewater discharges. No
known legal precedent has been established to define the extent of account-
ability of wetland dischargers. Once the need for ownership or legal control
has been established, the question of EPA funding will need to be addressed.
The resolution of this issue will require a discussion of treatment vs.
disposal (Section 5.3) as well as a review of current EPA regulations and
policies.
State definitions of "waters of the state" and the extent of state juris-
diction is another issue related to the ownership of wetlands. Only Ken-
tucky, North Carolina and South Carolina do not provide for exemptions to
waters of the state. All other states in EPA Region IV exempt waters totally
confined and retained on private property under single ownership. In many
cases, the extent of state jurisdiction will need to be determined on a
site-specific basis. The potential for discharging to private wetlands
outside of the state jurisdiction needs to be further addressed.
353
-------
9.0 SUMMARY
9.2 Critical Institutional Considerations
9.2.3 NPDES Permit Process
MODIFICATIONS MAY BE NECESSARY TO IMPROVE IMPLEMENTATION
OF WETLAND DISCHARGES
Under existing laws and regulations, the discharge of
wastewater effluent to most wetlands requires an NPDES
Permit. However, most state permit programs do not
recognize the specific nature of wetland systems. Modi-
fications to the permit process, including modeling and
monitoring requirements, may be necessary to improve the
implementation procedures and insure adequate protection
and use of the wetland resources.
The National Pollutant Discharge Elimination System (NPDES) was estab-
lished by the Federal Water Pollution Control Act of 1972 in order to
regulate the discharge of pollutants into the nation's waters. Under the
terms of the Act, the states were encouraged to establish their own water
quality standards and criteria leading to the administration of their own
permit program under the guidance of EPA. To date, only Florida and Kentucky
have not received authority from EPA Region IV to administer the NPDES Permit
Program.
A review of state legislation and regulations indicates a wide range of
variation in terms of special consideration for wetland discharges. Only
Florida and South Carolina have official wetland disposal policies. Only
South Carolina and North Carolina define swamp waters in terms of water
quality, although all states recognize that characteristics of natural waters
may be below specific standards and criteria. Definitions of "waters of the
state" are generally similar, but only Florida defines the landward extent of
waters of the state through the use of detailed species lists. Methodologies
for determining wasteload allocations and effluent limitations also vary
widely with some states applying standard stream models while other states
use baseline studies and qualitative analyses. Monitoring requirements also
vary from state to state with only Florida requiring special monitoring for
experimental wetland discharges.
Although most states do not distinguish wetlands from other waters of the
state for purposes of permitting wastewater discharges, provisions in the
laws and regulations allow for flexibility in applying water quality
standards and monitoring requirements. Therefore, the distinct nature of
wetland systems can often be accommodated; however, there is no assurance
that standards and requirements will be applied consistently within a state
or between different states.
Understandably, regulations and requirements will vary between states in
order to meet specific needs. In view of the variability of wetland types,
flexibility in applying water quality criteria is necesary, within a state as
well as between states. However, consistency in permitting procedures may be
essential at both the state and regional levels in order to provide protec-
tion for wetland resources and avoid economic inequities.
354
-------
9.2.3 Continued
The initial step to assuring consistency in the application of criteria
and requirements is the precise definition of wetlands for the purpose of
wastewater management. In some cases, accepted regulatory (COE) or
biological (FWS) definitions may be adapted. However, in other instances,
water bodies which have water qualities characteristic of wetland systems may
not be defined as such. Systems commonly referred to as swamp creeks,
sloughs, oxbow lakes and various other dystrophic systems may or may not be
considered wetlands for the purpose of permitting discharges. In several EPA
Region IV states, as long as a discernable channel or flow is present, the
system is modeled in the same manner as any other riverine or stream system.
Official policies based on an established wetland definition would be
helpful in consistently applying wasteload allocation and effluent limitation
procedures. The variability of wetland systems will likely require some
degree of qualitative analysis; however, as long as the methodologies and
procedures are established, consistency in application could be achieved.
Policies concerning monitoring requirements for wetland discharges would also
be useful in increasing the knowledge of wetland systems while insuring
protection of the resource. Evaluation criteria will be needed in conjunc-
tion with the monitoring requirements in order to judge the extent of wetland
degradation or enhancement.
Proposed changes to EPA water quality standards regulations may help over-
come some of the permitting difficulties associated with wetland discharges.
Revisions to use classifications based on use attainability and benefit-cost
assessments and the establishment of site-specific criteria may provide
states with a mechanism for addressing the specific characteristics of wet-
lands systems. In addition, the use of varying levels of aquatic protection
will allow for modifications even within the fish and wildlife use classifi-
cation. The actual impact of these proposed regulations on the use of wet-
lands for wastewater disposal remains hypothetical at this time.
A streamlined and straightforward permit process is also a major insti-
tutional consideration. Although precise problems or deficiences have not
been identified with any of the state permit processes, several wetland dis-
chargers have expressed dissatisfaction with the regulatory requirements (see
Section 3.0). Consideration should be given to the fact that most wetland
discharges are from small municipalities or package plants. Therefore, added
regulatory burdens or delays could severely reduce the implementability of
wetland disposal for those entities that could potentially benefit the most.
355
-------
-------
*$
i ,*x*r/" l ', v*"7"''' ' ''
- A '" "
SECTION 10
RECOMMENDATIONS FOR PHASE II
-------
-------
10.0 RECOMMENDATIONS FOR PHASE II
PHASE II PRODUCTS NECESSARY FOR DECISION MAKING
Phase II is designed to provide tools for assessing the
feasibility of potential wetlands discharges. Its
products are necessary for decision making and meeting the
objectives of the EIS. Information gained from Phase I
must be incorporated into a format and process amenable to
consistent decision making.
The Phase I Report has summarized key scientific, engineering, and
institutional considerations associated with wastewater disposal to wetlands.
Further, Phase I has profiled existing wetlands discharges and associated
policies in .each of the eight Region IV states.
. As a result of.Phase I efforts,- the broad extent of wastewater discharges
to freshwater wetlands in Region IV has been documented. However, most of
the existing discharges have been developed without design criteria, have
little basis for effluent limits, are delineated and defined inconsistently,
and incorporate few safeguards for or monitoring of critical wetland
functions.
As envisioned, Phase II is primarily intended to provide tools for
decision makers for evaluating wastewater discharges:to wetlands. -The goals
of Phase II are to identify, evaluate and recommend available and appropriate
pr-oced,ures or analytical tools to address each of the key institutional,
scientific and engineering factors identified in Phase I. The approach to
Phase II is centered on the need to develop procedures for assessing
potential wetlands discharges and filling data voids that are important to
that-process. A decision-tree approach is one that clearly defines the areas
of importance which should be addressed to have a sound basis for decision
making. "
Figure 10.0 provides a brief overview of the major components of a
decision-tree for wastewater disposal to wetlands.
The remaining EIS products include, as a minimum:
1. Institutional procedures to satisfy local, state and federal regulatory
or program requirements. ,
2. Scientific procedures or tools to ^identify and evaluate important
ecological' impacts, .;• ,
3. Engineering guidelines to assure maintenance of wetland functions and
values. • .
4. Procedures for collecting information needed by decision makers
5. Case Studies to test tools and procedures
6. Phase II Report
357
-------
10.0 Continued
7. Handbook of procedures and analytical tools for evaluating wastewater
discharges to freshwater wetlands
8. Draft and Final EIS.
The tasks leading to each of these products will be conducted in close
association with a representative of each Region IV state.
359
-------
XIQNHddV
IT NOI1D3S
-------
-------
Appendix A. Degree of Importance (I) and Status of Knowledge (K) of Key Areas of Importance
in .iydroljgically Isolated Systems (H = High, M = Medium, L = Low).
Area of
Importance
Geomorphology
Underlying Geology
Soils
CnnTS D • Car°lina Savannah, Marshes, White
Dome Pocosm Bay_ Wet Prairies Wet Meadows Cedar Boas
M M M M H L M M MM ML
HHHHHMHM HM HL
Drainage Basin
Characteristics
Vegetation
Material Cycling
Adaptations
Fire Frequency
cu Dominant Vegetation
t—'
Subdominant Vegetation
Succession
Productivity
Rare Endangered
Ecotypes
Hydrology
Groundwater
Surface Water Run)ff
Infiltration
Budget Predictabi ity
Fluctuation of Water
Depth
Water Quality
Chemical
DO
H
M
M
H
L
H
M
H
H
M
H
L
M
M
H
H
M
H
H
H
H
M
K
M
H
L
M
M
H
M
M
H
H
H
M
L
H
M
H
L
M
M
H
M
M
H
H
H
M
L
M
M
H
L
L
M
H
M
M
H
H
H
M
L
H
M
M
L
L
M
H
M
M
H
H
H
H
L
L
M
L
L
L
M
M
M
M
H
H
H
M
H
M
M
M
H
M
M
M
M
M
M
M
H
L
M
M
M
M
M
M
H
L
M
L
L
M
M
M
H
L
M
L
M
M
M
M
H
L
M
\
L
L
-------
Appendix A. Continued
Area of
Importance
PH .
Nutrient Levels
Metals, Toxins,
Indus. Effluent
Physical
Temperature
Turbidity
Biological
Macrophyte Increases
Habitat Alteration
CO
ro Threatened & Endan-
gered Species
Algal Bloom
Public Health Vectors
Microbial Respiration
Cypress
Dome
I
M
M
H
L
L
L
M
H
L
H
M
K
M
H
M
H
H
H
M
H
H
M
M
Pocosin
I
H
H
H
M
L
M
H
H
M
H
M
K
M
L
L
M
H
L
L
M
M
M
M
Carolina
Bay
I
H
H
H
M
L
M
M
H
M
H
M
K
L
L
L
M
H
L
L
M
M
M
M
Savannah,
Wet Prairies
I
H
M
H
L
L
L
M
H
M
H
M
K
L
M
L
L
H
H
L
M
M
M
M
Marshes, White
Wet Meadows Cedar Bogs
I
H
M
H
M
L
L
M
H
M
H
M
K
L
M
L
L
H
H
L
L
M
M
M
I
H
M
H
L
L
M
H
H
M
H
M
K
L
L
L
L
L
L
L
L
L
M
M
Wildlife and
Recreation Value
Linkage to Other Systems
Nutrient and Sediment
Removal from Flood
Waters
Production of Wading/
Migratory Birds
Spawning Grounds for
Fish
Timber Production
L
M
M
M
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
M
M
L
L
L
M
L
-------
Appendix B. Degree ot Importance (I) and Status of Knowledge (K) of Key Areas of Importance
in Hydrologically Open Systems (H = High, M = Medium, L = Low).
en
Freshwater Bogue, Bayou,
Bottomland
Area of Hardwood Forest
Importance
Geomorphology
Soils
Underlying Geology
Drainage Basin
Characteristics
Vegetation
Material Cycling
Adaptations
Fire Frequency
Dominant Vegetation
Subdominant Vegetatioi
Succession
Productivity
Rare and Endangered
Ecotypes
Hydrology
Groundwater
Surface Water Runoff
Infiltration
Budget Predictability
I
H
M
H
H
H
L
M
M
M
M
H
H
M
M
H
K
M
M
M
L
M
M
M
L
M
H
M
L
M
L
M
Cypress, Mixed
Hardwood Strand
I
H
M
H
H
H
M
M
M
M
M
H
H
M
M
H
K
M
M
M
L
M
M
M
L
M
H
M
L
L
L
M
Riverine,
Lake Marshes
I
H
M
H
H
H
L
M
M
M
M
H
H
H
M
H
K
M
M
M
M
M
L
M
L
H
M
M
L
M
L
M
Tidal
Wetlands
I
H
M
H
H
H
L
M
M
M
M
H
M
M
M
H
K
M
M
M
M
M
L
M
L
L
H
M
L
L
L
M
Brake Oxbow,
Slough
I
H
M
M
H
H
L
M
M
M
M
H
H
H
M
H
K
M
M
M
M
M
L
M
L
L
L
L
L
M
L
M
Fluctuation of Water
Depth
Water Quality
Chemical
DO
-------
Appendix B. Continued
Freshwater Bogue, Bayou,
Bottomland
Area of Hardwood Forest
Importance
Chemical
pH
Nutrient Levels
Nutrient Retention
Metals, Toxins
Indust. Effluent
Physical
Temperature
Turbidity
Biological
Macrophyte Increase
Habitat Alteration
Threatened and
Endangered Species
Algae Blooms
Public Health
Vectors
Microbial Respiratior
Wildlife and
Recreation Valu ;
Linkage to Other iystens
Nutrient and Sedinent
Removal from Flool Waters
Production of Wad'ng Birds
Spawning for Fishes
Timber Production
Salinity Peak Modification
1
M
M
H
H
M
M
M
M
M
M
M
M
H
H
H
H
M
H
K
M
H
M
M
M
M
M
M
M
M
H
M
M
M
H
M
M
M
Cypress, Mixed
Hardwood Strand
I
M
H
H
M
M
M
M
M
M
M
M
M
H
H
H
M
H
K
L
M
M
M
M
L
M
M
M
H
M
M
M
H
L
M
M
Riverine,
Lake Marshes
I
M
H
H
M
M
M
M
M
M
M
M
M
H
H
H
M
H
K
L
M
M
M
M
H
M
M
M
H
L
M
M
H
M
M
M
Tidal
Wetlands
I
L
H
H
M
H
M
H
M
M
M
M
M
H
H
H
L
H
K
M
M
M
M
L
H
M
M
M
H
L
M
M
H
H
L
H
Brake Oxbo
Slough
I
L
H
H
L
L
M
H
M
M
M
M
M
H
H
H
L
H
K
M
L
M
M
M
L
M
M
M
M
L
M
M
H
L
L
M
-------
SECTION 12
BIBLIOGRAPHY
-------
-------
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U.S. Environmental Protection Agency
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