£EPA
May 1990
United States Office of Water Regulations Office of Policy, Planning
Environmental Protection and Standards and Evaluation
Agency
FEASIBILITY REPORT ON
ENVIRONMENTAL INDICATORS
FOR SURFACE WATER PROGRAMS
EXECUTIVE SUMMARY
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CONTENTS
Page
ACKNOWLEDGMENTS i
ACRONYMS iii
I. INTRODUCTION 1
II. DESIGNATED USE SUPPORT AND ATTAINMENT OF
"FISHABLE/SWIMMABLE" GOALS 5
III. SHELLFISH HARVEST AREA CLASSIFICATIONS 15
IV. TROPHIC STATUS OF LAKES 21
V. TOXICS IN FISH AND SHELLFISH 25
VI. BIOLOGICAL COMMUNITY MEASURES 31
VII. POLLUTANT LOADINGS FROM POINT SOURCES 45
VIE. SUMMARY CHARACTERISTICS OF PROPOSED INDICATORS 51
IX. CONCLUSIONS AND RECOMMENDATIONS 53
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ACKNOWLEDGEMENTS
This document was prepared for the U.S. Environmental Protection Agency, Office
of Policy, Planning and Evaluation (OPPE) and the Office of Water Regulations and
Standards (OWRS), by Temple, Barker & Sloane, Incorporated (TBS). The information
in this document has been funded in part by the United States Environmental Protection
Agency under EPA Contracts 68-01-7288, 68-23-3548, 68-C8-0040, and 68-W9-0080.
This report presents the results of a feasibility study conducted by OPPE and OWRS at
EPA Headquarters. The work was accomplished by the time and effort of Kim
Devonald, Joe Abe, Kristina Groome, Tom Born and Eric Hyatt of OMSE, Bruce
Newton, Wayne Praskins and Chris Faulkner of OWRS, Dan Farrow of the National
Oceanic Atmospheric Administration (NOAA) and Andy Schwarz, Tom Flanigan and
Sarah Morrison of TBS.
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ii
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ACRONYMS
BIOS A component of STORET which stores biological data
BMAN Benthic Macroinvertebrate Ambient Network
BOD Biochemical Oxygen Demand
BSC Biological Stream Classification system
CWA Clean Water Act
DDT Dichloro-Diphenyl-Tiichloro-ethane
DMR Discharge Monitoring Report
EDS Effluent Data Statistics
EMAP Environmental Monitoring and Assessment Program
EPA Environmental Protection Agency
EPT total number of Ephemeroptera, Plecoptera and Trichoptera in a sample
FDA Food and Drug Administration
FWS Fish and Wildlife Service
GAO Government Accounting Office
GIS Geographic Infoimation System
IBI Index of Biotic Integiity
I d Invertebrate Community Index
1WB Index of Well-Being
MBI Macminvertebrate Biotic Index
NASQAN National Stream Quality Monitoring Network
NAWQA National Water Quality Assessment program
NCBP National Contpminant Biomonitoring Program
NCC National Computer Center
NOAA National Oceanic and Atmospheric Administration
NPDES National Pollutant Discharge Elimination System
NSSP National Shellfish Sanitation Program
NST National Status and Trends program
OPPE Office of Policy, Planning and Evaluation
OR]) Office of Research and Development
OW Office of Water
OWRS Office of Water Regulations and Standards
PARs Polycyclic Aromatic Hydrocarbons
PC Personal Computer
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ACRONYMS (Continued)
PCBs Polychiorinated Biphenyls
PCS Permit Compliance System database
PIBI Potential Index of Biotic Integrity
P01W Publicly Owned Wastewater Treatment plants
RTI Research Triangle Institute
SIC Standard Industrial Classification
STORET STOrage and RETrieval (EPA’S computerized water data base)
STPs Sewage Treatment Plants
TBS Temple, Barker & Sloane, Inc.
TOC Total Organic Carbon
TOXNET TOXicology data NETwork
TRI Toxic Release Inventory
TSI Trophic Status Index
TSS Total Suspended Solids
USGS United States Geological Survey
WBS Waterbody System
WQI Water Quality Index
iv
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I. INTRODUCTION
This executive summary presents the results of a study on the feasibility of six
measures identified as potential environmental indicators of the quality of the nation’s
surface waters. The complete feasibility report is available from the Environmental Results
Branch, EPA Headquarters (phone FFSI(202) 382-4900). It provides more background
information about the project, discusses each indicator in more detail, and contains additional
graphical presentations of the indicators.
The feasibility analysis is the second portion of a three-phase project jointly managed
by the Office of Water Regulations and Standards (OWRS) and the Office of Policy,
Planning and Evaluation (OPPE) at EPA. The first phase consisted of identifying and
describing a series of potential indicators for freshwater, estuarine and coastal environmental
quality, and holding a workshop of federal and State personnel to review, revise and narrow
down the candidate indicator list. Three reports were completed in Phase One: Resource
Document for the Workshop on Environmental Indicators for the Surface Water Program
( March 28-29. 1989), Workshop on Environmental Indicators for the Surface Water Program
( March 28-29. 1989) , and Results: Workshop on Environmental Indicators for the Surface
Water Program (July 1989) . In the second phase, contractors and EPA personnel assessed
the feasibility of reporting on the set of indicators selected at the workshop. These were
selected as most meaningful and practical for one or more of the following purposes: status
and trend reporting; overall water program evaluation, and evaluation of the effectiveness
of individual program components (e.g., point source regulation, or toxic chemical controls).
The present report addresses questions relating to data availability, the degree to which the
proposed measures meet the criteria of a “good” indicator, and which of the possible “uses”,
described further below, is met by the measure. In the third phase of the project, EPA and
State personnel will develop options and recommendations for specific applications of the
indicators by States, Regions, or EPA Headquarters.
The use of environmental indicators is becoming an increasingly important evaluation
tool for federal and State environmental programs (Figure 1-1). Carefully chosen indicators
of surface water quality can help answer two fundamental questions:
• What is the quality of surface waters, and
• How are we doing in our efforts to improve it?
Environmental managers at EPA and elsewhere can use indicators for several specific
purposes related to these general questions, including:
• Identifying trends over time and space;
• Evaluating program effectiveness;
• Targeting resources to areas with greatest environmental impact;
• Targeting resources to areas of potential or developing problems; and
• Communicating results to the public and legislators.
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Figure I-i
Continuum of Indicators
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The six environmental indicators analyzed in this report are:
• designated use support and attainment of “fishable/swimmable” goals
• shellfish harvest area classifications
• trophic status of lakes
• toxics in fish and shellfish
• biological community measures and
• pollutant loading from point sources.
The following six chapters are devoted to each of these indicators. Strengths,
weaknesses and possible improvements for each indicator are contained at the beginning of
each chapter and summarized at the end of the report. Evaluation criteria used in the
feasibility analysis included data availability, data consistency/comparability, spatial and
temporal representativeness of data, utility in trend assessment, relationship to ultimate
impact, scientific defensibility, sensitivity to change, relationship to risk, cost of data
collection and analysis, relationship to existing programs and presentation value. Selected
graphical examples from the full report are included in each chapter to demonstrate the
presentation value of each indicator. Conclusions and recommendations from the study are
listed at the end of the report.
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4
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II. DESIGNATED USE SUPPORT AND
ATTAINMENT OF “FISHABLE/SWIMMABLE” GOALS
SUMMARY
Description of the Indicator
This indicator uses Information provided by the States to EPA on the status of
their waterbodies. The Information, Included in reports required under section 305(b)
of the Clean Water Act (CWA), describes to what degree Individual waterbodies are
meeting their designated uses. State and local governments assign designated uses to
waterbodies and determine the criteria by which they will be evaluated as part of their
water quality standards.
States also report to EPA on the extent to which their waters meet the Nfishable
and swimmable” goals of the CWA. This differs from designated use support in the types
of information each State considers adequate to allow a determination (e.g. monitored
versus professional judgement).
Possible Applications
The State data are currently used in the development of a national assessment of
water quality. This is the States’ and EPA’s primary vehicle for informing Congress of
the state of the nation’s waters. At the March 1989 workshop on developing surface
water indicators, the workgroup on status and trends recommended that udesignated use
support” be used as a “high visibility” indicator to generate attention and solicit
questions about the underlying results.
Strengths National data collection and reporting
system is already in place and used by
all States (Recently Computerized).
uFishable/Swimmablen reporting provides
information on goals of primary Interest to
the public and is easily understood by
general public.
Weaknesses Since State reporting is Inconsistent and not
standardized, measures cannot be used to evaluate
trends. Within a State, inconsistencies exist from
one reporting cycle to the next.
Possible Improvements Increase use of the Waterbody System
to allow EPA to aggregate results; Increase
use of reach numbers or other geographic
Identifiers to facilitate trend assessments;
Increase systematic ambient monitoring by States
(e.g. returning to certain subsets of waters
regularly to establish trends).
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II. DESIGNATED USE
EVALUATION CRITERIA
Data availability Good-States currently collect information on a
biennial basis and report it to EPA through the
305(b)reports.
Data consistency/comparability Poor-No consistent basis for monitoring sampling
design from State to State and water quality
standards vary.
Spatial representativeness Fair/Poor-Although the same waters are not
assessed from one cycle to the next, the Identified
bodies are representative of those types of waters
within a State.
Temporal representativeness Fair/Poor-It is primarily based on physical-
chemical data which are transient.
Utility in trend assessment Poor-Since the same waters are not assessed from
one cycle to the next, it is impossible to determine
trends. Waterbodies can be reported as evaluated,
meaning the data from the last cycle is sometimes
just repeated in the next report.
Relation to ultimate impact Good-For Fishable/Swimmable since the degree to
which these goals are met Is the ultimate impact.
Fair-For designated use since the exact impact of
the chemical/physical data are not known; Better if
biological community data are included in the use
attainment determination.
Scientific defensibility Fair/Poor-Methodologies vary from State to
State, therefore, the degree to which designated use
and fishable/swimmable determinations are
defensible as true measures of water quality is also
variable.
Sensitivity to change Poor-Categories are too broad to detect
incremental changes.
Relationship to risk Fair/Poor-The relationship is tenuous for both
ecological and human health risks. The link from
chemical/physical to actual environmental damage
is ill-defined. Changes in fishable/swimmable do
relate to potential human health risk, but the
connection with designated use is less strong.
Cost to coHe and analyze data Low-States already engaged in data collection;
Improved collecting/reporting would require
incremental cost increases.
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II. DESIGNATED USE
EVALUATION CRITERIA
RelationshIp to existing programs Good-Required as part of 305(b) CWA
requirements.
Presentation value Good-Fairly easily understood by the general
public; Can be presented using maps and graphs.
U.S. EPA Headquarters Library
Mali code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
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Percentage of
Total Waters
Figure 11.1
Nationwide Summary of CWA Fishable Goal 1988
100
80
60
40
20
0
Source: 1988 305(b) Reports
Not Assessed
• Not Meeting
• Meeting
Rivers Lakes Estuaries
8
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Percentage of
Total Waters
Figure 11.2
Nationwide Summary of CWA Swimmable Goal 1988
100
80
60
40
20
0
Not Assessed
I Not Meeting
I Meeting
Rivers Lakes Estuaries
Source: 1988 305(b) Reports
9
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Percentage of
Total Waters
Figure 11-3
Nationwide Designated Use Support 1988
100
80
60
40
20
0
Not Assessed
Not Supporting
Partially Supporting
U
U
U Threatened
Fully Supporting
Rivers Lakes Estuaries
Source: 1988 305(b) Reports
10
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Figure 11-5
Percentage of Assessed River Miles Per State Meeting CWA
Fishable Goal in 1988
U]Ur
El
Stales not Reporting
Source: 1988 305(b) Reports
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80-89%
70-79%
111111 States not Reporting
Figure 11-6
Percentage of Assessed River Miles Per State Meeting CWA
Swimmable Goal in 1988
90- 100%
Less than 70%
Source: 1988 305(b) Reports
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Figure 11-7
Percentage of Assessed River Miles Per State Fully Supporting
Designated Use in 1988
F
90 100%
80-89%
I ] 60-79%
11111 States not Reporting
‘t’
r
r
Source: 1988 305(b) Reports
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Figure 11-8
Percentage of Total River Miles Assessed Per State in 1988*
11111 Slates not Reporting
H
States wlthoi arrows or e al sign did n report ki 1906
2
50-74%
75-100%
U
U
Less tiw 25%
25-49%
•Y.$r4Oy r comparisons are for Illustrativ, purposes only.
Source: 1988 & 1986 305(b)
Reports
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III. SHELLFISH HARVEST AREA CLASSIFICATIONS
SUMMARY
Description of the Indicator
The indicator identifies potential contamination of coastal waters by investigating
the degree to which State governments close off or limit access to shellfish harvesting
areas. The State agencies classify different areas based on water quality monitoring (not
shellfish tissue monitoring). The resulting information constitutes one of the nations
largest consistently collected water quality data bases. States report this information to
NOAA as part of the National Shellfish Sanitation Program (NSSP), which provides
well-defined guidelines to the States. States do, however, vary in their interpretation of
the guidelines. This measure is one of five indicators chosen by NOAA in its state of the
marine environment report.
Possible Anplications
Shellfish harvest areas are the most commonly monitored feature of coastal
waters and data are readily available. On both a nationwide and regional level, data
provide a good Indication of the general status of marine waters and, with continued
improvements, can be used to assess trends.
Sire nciths Data collection has been consistent for over 20
years on a nationwide basis using National Shellfish
Sanitation Program (NSSP) guidelines. National
standards developed by FDA are used by all States.
Indicator is easily understood by public and policy
makers.
Weaknesses Variations in State to State decision-making on
classifications limit nation-wide comparisons
somewhat; Reclassifications are not always due to
water quality changes, but in past have reflected
changes in areas monitored; Only fecal coliform
levels are monitored (which are not bacteria of
concern, but are indicators of pathogens); The
Indicator is not well reported for open coastal (as
opposed to estuarine) waters.
Possible Improvements Greater consistencies in classifications would allow
for nationwide comparisons; Correlating with
other data, such as sediment and shellfish tissue
contamination would provide a more complete
indicator of surface water quality.
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UI. SHELLFISH
EVALUATION CRITERIA
Data availability Good-NOAA publishes the National Shellfish
Register covering all continental coastal States
approximately every five years. Some States
include shellfish information in their 305(b)
Reports.
Data consistency/comparability Fair-Even with inconsistencies in classifications
the data are consistently presented. NOAA
personnel visit States and take into account State-
to-State differences to standardize the data for the
national report. Physical and administrative
differences limit comparability of different regions
(East Coast-West Coast).
Spatial representativeness Good-The majority of estuarine areas are
classified as shellfish growing waters
(approximately 95% of East Coast estuarine
areas), and are consequently covered by the
indicator. (Open coastal waters are not very well
represented.)
Temporal representativeness Good-Most stations sample at a minimum of 5
times annually (conditional classifications more
often), therefore, seasonal variation is taken into
account. Reasonably consistent data sets exist for
most areas since the 1970’s.
Utility in trend assessment Fair-Data are available to assess trends, however,
not all changes in classification are the result of
water quality changes. NOAA does distinguish
changes which are the result of water quality from
those due to changes in areas monitored for
Northeast, Mid-Atlantic, and West Coast. These
data will allow for trend assessments.
Relation to ultimate impact Fair-Relationship between shellfish harvest area
classification and ultimate impact Is limIted
because only fecal coliform levels are monitored.
Coliform levels do not relate directly to human
health impacts, rather they are an indicator of the
possible presence of pathogens.
Related factors Important-To have a more useful indicator,
the ancillary data on pollutant sources should be
used. (NOAA began collecting these data in the mid-
1980’s.)
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Ill. SHELLFISH
EVALUATION CRITERIA
Seientific defensibility Fair-Not all classifications are the results of
monitoring; Coliform levels are only an
indicator of pathogens; Quality of sampling varies
among states.
Sensitivity to chance Good-Can get immediate reading of change in
coliform levels.
Relationship to risk Fair-Difficult to relate collform levels directly to
health risk, but Indirect qualitative relationship
definitely exists; Monitoring primarily coliform
levels excludes factors other than sewage pollutants
related to risk; Not relevant to ecological risk.
Cost to collect and analyze data Moderate-State monitoring programs vary in size
and cost though reporting to NOAA is well
established and consistent; Due to high cost, States
only monitor fecal coiiform levels, monitoring
actual pathogens would be prohibitively expensive.
Reiationshio to existino pronrams Good-NOAA’s National Shellfish Register presents
shellfish harvest area classifications and assesses
status, trends and pollution sources. States use
classifications to assess designated use support, and
to target sewage treatment plant and combined
sewer overflow upgrade activities.
Presentation value Good-Shellfish harvest area classifications are
understandable to government decisionmakers and
the public. Status and trends can be easily
presented on graphs and charts.
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Figure ill-i
Shellfish Harvest Area Affected by Pollution Sources
Northeast Region (1988)
Boating •
Wlldllfe(Animal Waste) •
Ag Runoff
Urban Runoff
Septic Systems
Combined Sewers
Industry •
Sewage Treatment Plants
Total Harvest-Limited Area -
I I
0 100 200 300 400 500 600
Area (thousand acres)
Note: ‘Total harvest-limited area Includes: Conditional, Restricted and
Prohibited waters.
‘Multiple pollution sources are often identified for a single harvest-
limited area, therefore the sum of the area affected by sources in an
estuary is usually greater than the amount of harvest-limited area.
Source: NOM
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Figure 111-2
Shellfish Harvest Area Affected by Pollution Sources
Mid-Atlantic Region (1988)
Boating
Wildlife(Animal Waste)
Ag Runoff
Urban Runoff
Septic Systems
Combined Sewers
Industry
Sewage Treatment Plants
Total Harvest-Limited Area
i
50
100 150 200 250
Area (thousand acres)
300 350
Note: 'Total harvest-limited area includes: Conditional, Restricted and
Prohibited waters.
•Multiple pollution sources are often identified for a single harvest-
limited area, therefore the sum of the area affected by sources in an
estuary is usually greater than the amount of harvest-limited area.
Source: NOAA
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Figure 111-6
1985 National Shellfish Harvest Area Classifications
(Subdivided by Regions)
Area Classified
(millions of
acres)
6
5
4
3
2
0
North- Mid-
east Atlantic
South- Gulf of
east Mexico
Source: 1985 NOAA Data
I Prohibited
I Restricted
Conditional
Approved
West
Coast
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IV. TROPHIC STATUS OF LAKES
SUMMARY
Descrbtion of the Indicator
Trophic status is the most commonly used measure of status and trends lake
water quality. Eutrophication is a process by which a waterbody becomes rich In
dissolved nutrients, filled with detritus, and seasonally deficient In dissolved oxygen to
the extent that aquatic life Is Impaired. Eutrophication can result from the slow, natural
aging of a lake or can be accelerated by excessive enrichment of nutrients (primarily
phosphorus) from pollution sources such as fertilizer, sewage and detergents. States
report the trophic status of publicly owned lakes in their 305(b) reports and some
States report into the Waterbody System (WBS). States vary in their methods of
determining trophic status with the majority using Carlson’s Trophic Status Index
(TSI). As a result of the different reporting methods, EPA must slightly modify the data
of some States to achieve a nationwide comparison of trophic status.
Possible Applications
Eutrophication data provide a measure of the quality of lakes and support State
program managers In targeting specific monitoring or enforcement activities. The rapid
eutrophication of a lake signals a pollution problem and can serve as a warning system.
Although inconsistencies and data gaps in monitoring and reporting limit
nationwide evaluations, the indicator does present some useful qualitative information
regarding the nation’s lake water quality.
Strengths Reporting the trophic status of publicly owned
lakes is required by Clean Water Act (CWA)
314(a); Provides a scientifically defensible
measure of the ecological health of lakes.
Weaknesses Regional geographic and hydrologic differences in
lakes may limit national comparisons. A eutrophic
condition does not necessarily mean that a lake does
not support its designated use(s). The number of
lakes evaluated by trophic status fluctuates, making
trend analysis difficult. Seasonal fluctuations in
trophic status are not always taken into account.
Possible Improvements Establish a baseline number of lakes to determine
trends; Record seasonal fluctuations; Report both
number of lakes and lake acres.
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IV. TROPHIC STATUS
EVALUATION CRITERIA
Data availability Good/Fair-Reported in 305(b) reports, Clean
Lakes Ust and In the Waterbody System (WBS).
Currently six States put trophic data in the WBS,
although the number is expected to increase in the
future. EPA can compare results from States using
different methods.
Data consistency/comparabilIty Good/Fair-The majority of States use Carison’s
TSI. Others use methods suited to individual needs.
Some States only report trophic status by number
of lakes and not acreage.
Spatial representativeness Fair-States only assess a portion of their total
lakes.
Temporal represantativeness Fair-There Is no consistent accounting for
temporal fluctuations.
Utility in trend assessment Fair-The number and frequency of lakes monitored
and assessed is not consistent enough to assess
trends. If a baseline number of lakes assessed were
established then utility in trend assessment would
begood.
Scientific defensibility Good-Carison’s TSI is a scientifically defensible
measure. Other methods such as professional
judgements may be not entirely consistent, but are
often technically sound in their own right. They
are not necessarily less valid for purposes of the
Indicator program.
Sensitivity to chanae Good-TS1 in particular has a range of 1 to 100 and
can show incremental changes.
Relationship to risk Good-For ecological risk rapid eutrophication is
strongly related. This indicator is not directly
relevant to human health risks.
Cost to collect and analyze data Low-Monitoring and analysis systems are already
in place and budgeted at the State level, and the
measurements are relatively inexpensive compared
to other water quality measures (e.g. toxics).
Relationship to existing programs Good-Trophic status is reported in 305(b)
reports, Clean Lakes classification report, and used
in State management programs.
Presentation value Good/Fair-Eutrophication is not as easily
understood by the public as other indicators but can
be explained. Presentations can consist of national
maps, accepting comparability of varying State
results.
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Figure IV-3
Percentage of Assessed Lakes Per State Classified as Eutrophic (1988)
0-24%
States nc* Repodklg
.H eres..droph c Lakes are Induded esircptiic %.
.OnIy Rh. Rc aI number c Rakes th tro h c dassMfk *Rons were a nsidered.
(L..-l ..s with w w i Vciphlc status were nc4 taken o a w* br the tatal nsxnber cA assessed Rakes.)
Sour : 1988 305(b) R ods
75-100%
II I
i..
50-74%
El
25-49%
.. :..:.‘ .
LI
Do nst detarm ie Woptb status k mwiner ccnsbaterd with c*her states;
See TthIe V-2.
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Figure IV-4
Percentage of Assessed Lake Acreage Per State Classified as Eutrophic (1988)
0-24%
U
4- perutdrcçi c ac age kicàided Ii eutrophic %.
ry the 1 . aaeage w*h btphic d s ons we ns1dered.
(Le.lakes with unknown trophic status we not taken leo aceount for the total nunter at assessed aaeage.)
Stales not Reporting
Source: 1988 305(b) Reports
Do not determine tmptitc stalus in manner consistent with other states:
See Table V-2.
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V. TOXICS IN FISH AND SHELLFISH
SUMMARY
Description of the Indicator
This proposed indicator measures the accumulation of pesticides and other toxic
chemicals in fish and macroinvertebrate tissue. Currently, several Federal Agencies
including the Fish and Wildlife Service (FWS), the National Oceanic and Atmospheric
Administration (NOAA) and the Environmental Protection Agency (EPA), as well as many
State Agencies collect these data. States commonly use the information to help develop
fish consumption advisories. FWS and NOAA studies are ongoing and can provide status
and trend information on a regional level. The State programs vary in the type of
animals tested, the amount and quality of the testing done, the chemicals that are
analyzed and the way the results are used. To use on a national level the State data will
require better data storage and accessibility. FWS and NOAA data are typically for
whole-fish or liver samples, and thus indicative of ecological risks but not human health
risks. EPA and State data are often for edible tissue fillets, and thus can be used to
estimate potential risks to human consumers.
Possible Applications
The FWS and NOAA data can be used directly to support regional status and trend
identification for river and marine systems. EPA will have to decide how it wants to use
the State data in a regional or national assessment program. The Agency might be able to
develop trend data for selected States and sites if it were to ask States to provide data
from locations that are part of ambient monitoring systems.
Strenaths The accumulation of toxicants in fish and shellfish
tissue can provide an indication of the general
quality of the water resource, at least with regard
to specific chemicals and the implications of their
presence. Some nationally consistent data sets
exist. Many States collect tissue contamination
data. There is a lot of interest among the general
public, especially with regard to any human health
risks associated with toxic contamination of fish
and shellfish.
Weaknesses The actual ecological implications of fish and
shellfish contamination are a subject of
controversy. There is a lot of variability among
States in the chemicals tested for and in the quality
of the analysis. State data are hard to retrieve
if they are put into STORET.
Possible Improvements Increase in the use by States of BIOS as central
repository for storage and retrieval of data; Have
States include more information in their 305(b)
reports; Greater coordination among various
federal agencies (FWS, NOAA and EPA) in site
selection and identification of chemicals to be
tested; Possible extension of EPA Bioaccumulation
Study.
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V. TOXICS
EVALUATION CRITERIA
Data avaIlability Good-For FWS and NOM data; Available in periodic
reports and from computerized databases; Also, data
should be readily available from EPA’s
bioaccumu lation study.
Fair-State data are maintained on State databases
which may or may not be automated. Some States
put data into STORET, but retrieval of information
from that system is difficult.
Data consistency/comparabIlity Good-For EPA Bloaccumulatlon Study and FWS and
NOAA studies, consistent analytical methods are
used throughout the country. Although different
fish species are, by necessity, used in different
regions, the differing samples can be used for
comparison purposes.
Fair/Poor-States have a lot of variability
in the type of chemicals tested for, species tested,
and the quality of the analysis.
Spatial representativeness Good-FWS sites were chosen to provide national
information on status and trends. Benthic
surveillance and mussel watch sites are located
near urbanized areas so as to be representative of
the general areas in which they are located.
Falr-Bioaccumulation study; Some sites were
randomly chosen, others were located in
undisturbed areas, areas of important fisheries and
at problem areas. Each type of site could be
representative of simIlar sites around the country.
Variable-State information is better in States
with ambient monitoring networks.
Temporal representativeness Good-The presence of contaminants in fish and
shellfish tissue is more temporally consistent than
measuring for the chemicals in the water column,
since they are less transient. In the National
Contaminant Biomonitoring program (NCBP),
sampling always occurs in the fall to increase
temporal comparability and similarly bivalves are
always tested in the fall in NOAA’s status and trends
program.
Variable-The State testing results vary not only
between States but may also change within a State
from one year to the next, affecting temporal
comparability.
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V. TOXICS
Utility in trend assessment
Scientific extensibility
Sensitivity to chance
Relationship to risk
Cost to collect and analyze data
EVALUATION CRITERIA
Good/Fair-Trie FWS study is designed specifically
to measure trends for specific contaminants in fish
tissue. NOAA data will also support trends as
monitoring continues into the future. The state data
that is done at fixed monitoring stations would be
useful for trend monitoring. However, a lot of
monitoring Is done for "special studies" and would
not support the development of trends.
Good-FWS and NOAA studies use well-defined and
accepted study protocols as does the EPA
Bioaccumulation study. State activities are much
more variable.
Fair-However, the utility of this measure to detect
changes in the toxic load would depend to a great
extent on the species involved and their tendency to
accumulate particular chemicals. The FWS study
demonstrated the decline In the use of certain
pesticides. The pesticides were still being found
long after their use was discontinued, which is
important in demonstrating continued impact, but
shows that natural response lags will slow down
the ability to demonstrate environmental results.
Non-linear relationships of loads to ambient
concentrations in tissues mean that modest
incremental changes in pollutant inputs will not
always be distinguishable from tissue monitoring.
Fair-For bivalves and where fish fillets are
analyzed the measure provides information
relevant to human health risks. The measure is
directly related to ecological risk. However,
quantitative information on the actual
environmental impacts of the accumulated toxicants
is usually not available.
Moderate/High-Costs for tissue toxicity tests
and their evaluation can be high. Accordingly,
studies such as EPA's Bioaccumulation study may
not be repeated.
Relationshio to existing programs
Presentation value
Good-Several Federal Agencies are already
doing testing as are States in conjunction with FDA.
States can report findings in the 305(b) reports.
Good/Fair-The information is understood by
the public and can in certain instances be well
displayed on maps. However, given the wide range
of variables in different studies, it is difficult to
get a "nationwide" view from State studies.
27
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Figure V-i
National
Contaminant Biomonitoring
in Freshwater
Program (NCBP)PCB
Fish (1980-81)
Residues
9 1.0 ppm
:J1.1_5 ppm
ppm
I
1111!:
I
L__; ;:\\.
Source: FWS
-------
Figure V-3
Total DDT in
Livers of Estuarine Fish
at 42 SItes in 1984*
Composites
Collected
*uomput j from original data for the 1984 NOAA Status and Trends Program.
Source: NOAA: A Historical
Assessment Report 1988
1
I asik I , AZ
Nshk R.y. AL
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30
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VI. MEASURES OF BIOLOGICAL COMMUNITY STRUCTURE
SUMMARY
Description of the indicator
The basic indicator is the health of the biological communities of water body segments, as
measured by monitoring and abundance of species expected to inhabit that type of water (and In
some cases, of species considered to be sensitive to polluted conditions). States use a variety of
biological community measures, with the Index of Biotic Integrity (based on counts of fish
species), other fish community Indices, and several types of macrobenthlc Invertebrate Indices
being the most common.
To use this indicator at the national level, we will attempt to combine data on the health
of biological communities in all monitored water bodies according to their qualitative rankings
according to the various indices used for bioassessments. That is, we will use only the
information on whether the biological community of a given segment was considered to be In
excellent, good, fair, or poor condition, considering all segments with the same qualitative
ranking as equivalent for the national evaluation. This approach was recommended by several
State and regional biologists in the workgroup on program eftectiveness evaluation at the March
1989 Surface Water Indicators Workshop, and was then voted one of the most highly rated
potential national indicators by the workgroup as a whole.
Possible Applications
Because the specific types of biological monitoring (i.e., which types of animals or
plants are counted) vary from State to State, only very qualitative reporting will be justified at
the national level. Such qualitative information could be useful for Federal planning and
targeting. It will not support site-to-site comparisons. However, the Agency believes that if
spatial data availability issues can be worked out, this indicator may support comparisons of
broad-scale trends in biological conditions among geographic regions. States, watersheds, etc.
At the State level, where consistent methods of monitoring and analysis can be assured,
sophisticated analyses of biological community data are already being done. Such analyses can be
used to support impact assessments for specific pollution sources, or to assess the results of
pollution control upgrades at particular facilities.
31
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VI. BIOCOMMUN1TY
Strengths This indicator is the most direct measure possible of
support of a Clean Water Act (CWA) goal, because
maintaining biological integrity is one of the legislative
mandates. The information is scientifically defensible, and
also makes sense to the public and decision makers.
Availability of data to assess the status of waters
nationwide is moderately good, with data available for some
waters in almost all States, provided that a decision Is
made to consider the various types of biological community
measures as comparable to one another In a broad,
qualitative sense.
Weaknesses The variety of approaches to assessing biological
community integrity means that no single approach will
likely ever be embraced by all States. This means that
only rough, qualitative comparisons of conditions from
place to place will ever be likely using this approach.
Also, biological monitoring Is now often done in special
studies rather than as part of ambient network monitoring,
so that there are relatively few locations where temporal
trends can be assessed.
Possible Improvements More consistent monitoring in space and time, i.e.,
establishing more monitoring network locations that will
be monitored repeatedly over time would allow trend
assessments for a larger portion of the nation’s waters
than is currently possible.
32
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VI. BIOCOMMUN1TY
EVALUATION CRITERIA
Data availability Fair - Most States use biological community monitoring
for at least a few critical water bodies, or for special one-
time studies. A number of States have incorporated such
monitoring into ambient monitoring networks, and
additional States may do so In the future. The proportion of
most States’ assessed water bodies in which biological
community monitoring is done is currently quite low.
However, the positive response of most States to recent
recommendations by State and federal agencies concerning
the benefits of biological monitoring Indicates that
biomonitoring will probably be carried out for larger
portions of many States’ surface waters in coming years.
Data consistency/comparability Fair - A variety of biological community measures are
commonly used, which differ greatly in the type of
organisms whose abundance is assessed, and in the
complexity of procedures for combining data on various
species’ abundance. Some measures are formulated into
sophisticated mathematical indices to take into account
habitat features and other environmental factors (e.g., IBI
based on ecoregions) while others are relatively simple
weighted sums of a few key species. The great differences
in the types of measures used means that data from State to
State, and sometimes within States, will not support
sophisticated ecological comparisons among sites or
regions. This indicator development project is
investigating whether biomonitoring experts concur with
the sense of the March 1989 Surface Water Indicator
Development Workshop that the biological community
indices commonly used for water quality assessments are
sufficiently comparable to be aggregated for qualitative
national status and trend analyses.
Ability to estimate Poor - The utility of biological community monitoring
derives from its direct nature. One is monitoring the
feature of the environment that water quality regulations
seek to protect, so that one cannot be fooled into falsely
believing the ecological protection goal of the CWA has been
met, as can occur when physical and chemical measures
are used. Attempting to Infer what biological conditions
are from non-biological measures would thus be contrary
to the basic reason that biological community measures are
desirable in the first place.
Soatial representativeness Fair - Biological community assessments are done in most
States, but often in only a small portion of the assessed
waters. The major challenge in using these assessments to
evaluate national status and trends will be working out
spatial data availability issues. It will be necessary to
identity segments where monitoring could be expected to be
representative of the segment as a whole, rather than of
33
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VI. BIOCOMMUNITY
EVALUATION CRITERIA
small, high impact areas subject to intensive study (such
as a point source discharge monitoring study).
While this issue of spatial representativeness is not a
trivial one, biological community measures in fact present
less of a problem than the chemical measures on which
State use-support assessments are traditionally based.
This is because biological communities tend to integrate
water quality conditions over space and time.
Temporal representattveness Good - Biological community health is more temporally
consistent in a given location than water quality Itself is,
because water column conditions are transient while
organisms remain.
Utility in trend assessment Fair- Biological community monitoring is sometimes
part of State monitoring networks designed for trend
assessment, in which case monitoring is repeated at fixed
locations over time. But other biomonitoring data are from
one-time studies that do not support temporal trend
assessments, and so would have to be excluded from a
national assessment intended to look systematically at
spatial and temporal trends.
Relation to ultimate impact Good - Damage to biological communities is one of the
ultimate impacts the CWA seeks to prevent. In relation to
the “fishable goal”, if the particular measure used assesses
organisms other than fish (e.g.. a benthic community
index), then the measure is still a very good indirect
indicator of impacts on fish, due to food web relationships.
Related factors ! Important - Data on habitat and water body type are
Ancillary information necessary to properiy interpret biological community
data, because the types of organisms composing a healthy
community vary according to substrate, depth, flow,
climate, etc.
Sciantific dafensibility Good - Most biological community measures currently
used by States have been developed, reviewed, and refined
by academic and government scientists and are very sound
technically. The concept of considering different measures
or indices as qualitatively equivalent for national
assessment purposes is tentatively considered sound by a
selection of federal and State biologists, but requires
testing and further expert evaluation.
SensitMly to change Good - Some particularly pollution-sensitive organisms
are typically included in each biological community index,
so that the biological community monitoring is an excellent
method to identify pollution impacts when they first
become ecologically significant.
34
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VI. BIOCOMMtJNITY
EVALUATION CRITERIA
Relationship to risk Good - Degradation of biological community structure Is a
direct measure of ecological impact.
Cost to collect and analyze data Moderate - Biological monitoring can be more expensive
than basic chemical monitoring for conventional
pollutants, but It is often less expensive than toxIc
chemical monitoring as presently done, and is much less
expensive than full-blown monitoring for all toxlcs of
potential concern.
Relationship to existino oroarams Good - States and EPA already have made provision for
reporting and analyzing biological community data as part
of the process for assessing use support and preparing
305(b) reports. Guidance on how to incorporate biological
community parameters more explicitly into State
standards will be refined by EPA in the next few years.
Presentation value Good - The concept of balanced biological communities is
well understood by decision makers and the public.
35
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Figure VI-2
Communities Sampled In River Biosurveys (1989)
U
0
9
Virgin I3Ionds
NONE (8)
lisIl (2)
OTHER BIOlA (18)
MACROINVERTEBRA1ES (9)
FISH AND MACROINVERTEBRATES
Source: RTI
-------
Figure VI-3
Illinois Streams Evaluated Using
Index of Biotic Integrity (IBI) (1989)
Note: This is a color map: If Report is photocopied,
use black and white map on next page for
distribution. Color maps are available from the
Environmental Results Branch, U.S. EPA (Phone
(FFSI2O2) 382-49(X))
ENV IRONIIENTAL PROTECT ION AGENCY
STORET SYSTEM
[ LLtNOIS RLACI-1E3
[ O COPflhtUN1TY OATf
NOVEMBER 14 1989
[ B 12. PRN’
- 4=CXCELLEt4T
3=G000
- I=FAIR
2=POOR
M* ** **** *****
PROECT ION - v LeERs EQJAL AREA
3CALE L:I 48 l2
, zi
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Figure VI.4
Illinois Streams Evaluated Using
Index of Biotic Integrity (IBI) (1989)
ENVlRONPIEt4T . PROTtCT!ON ENCT
STORET 3YSTEM
ELL(N015 R ACttS
810—COfIfIUNITY DATA
NOVEMBER 14 1989
I B 12. PRN’
I I Good
-••O--O--• Fair
—•—-•— Poor
Not: Thla map s du d m a co map
generaied from STORET to allow photocopying in *
black and white Color maps e available from the
Environmental Results Besnch. U.S. EPA (Phone
(F Sf202) 382-4900)
),‘
‘
\ (
p
•1
Excellent
4
39
-------
40
-------
Figure Vi-5
Illinois Streams Evaluated
Blotic Index
Using
(MBI)
Macroinvertebrate
Note: This is a color map: If Report is photocopied,
use black and white map on next page for
d ibution Color maps are available from the
EnvIronmental Resi Is Branch, U.S. EPA (Phone
(FFS 2O2) 38 49OO)
ENVIRONMENTAL PROTECTION A(ENCY
STORET SYSTEM
[ LLINOI5 REFiCME
[ O—COMf1UNIT’( DATA
NOVEMBER 14 1989
‘MB 12. PRN
- 4= XCELLENT
- 3=G000
I=FAIR
2=POOR
* - ** M - *****
PROJECT (ON - ALBERS EQUAL AREA
Cf Lf h( 48 3I2
(1989)
I ze 1
I
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Figure VI.6
Illinois Streams Evaluated Using
Macroinvertebrate Biotic Index (MB!) (1989)
ENVIRONI€PIffi - PROTECTION OICT
STORET SYSTEM
ILLLNOI5 REACtIE3
elo-COMMUNITY DATA
NOVEMBER 14 1989
‘M612.PRN’
— -Excellent
- 1-- +Good
Fair
Note: This map was reproduced from a color map
generated from S’1 )RET to allow photocopying in
black and white. Color maps we available from the
Ennjnental Rasulta Branch, U.S. EPA (Phone
(FF51202) 382-4900)
I)
I
F
C-
43
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44
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VII. LOADING ESTIMATES FROM POINT SOURCES
SUMMARY
Description of the Indicator
This indicator shows the location, magnitude, type and timing of pollutant discharges Into
receiving surface waters. Although loading estimates do not directly reflect the quality of the
water resource, they are a useful measure of the pollutant stress placed on the system and
provide an Indication of the effectiveness of regulatory programs In controlling pollutant
discharges.
Possible Apolications
Pollutant loading estimates can be used for evaluating progress made in some point
source control programs, and targeting future point source regulation and enforcement
actMtles. If time series of loads are available, trends In discharges can be depicted and
correlated with changes in treatment technologies, land use management practices, service
areas and production levels. Pollutant loading estimates are often the primary measures for
evaluating enforcement programs.
Strengths Data collection and reporting system is in place in all
States. The data are spatially and temporally fairly
consistent, with good correlation between pollutant
loadings and water quality. Indicator is easily understood
by public and policy makers and is closely tied to a major
regulatory program.
Weaknesses AvailabIlity and quality of data is limited, especially for
toxic compounds. Current data management system
(Permit Compliance System (PCS)) cannot be used
reliably to compute loads. Additional data collection
requirements are costly.
Possible Improvements Require permitted facilities to report seasonal and annual
loads; Modify PCS to allow computation of loads.
45
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V I I. LOADINGS
EVALUATION CRITERIA
Data availability Fair - Discharge Monitoring Reports (DMR) data for
majors are reported to PCS for all States, with varying
levels of participation and quality control. Greatest
amount of monitored data is available for wastewater
volume, and conventional pollutants, with much less data
available for metals and toxic organlcs. Availability and
quality of data for minors is variable, but is generally
much poorer than for majors.
Data consistency/comparability Good - Analysis methods are generally standardized for
permitted pollutants. Therefore, comparison of estimates
among States or regions is reasonable.
Ability to estimate FaIr - All load estimates are approximations. When
monitored data do not exist or are suspect, engineering
estimates can be substituted, with substantial reduction In
credibility.
Spatial representativeness Good - Because all major point sources are included in
PCS, data for majors is spatially representative. Data is
less reliable for minors.
Temporal representativeness Good - For major point sources, pollutant loadings are
monitored on a daily, weekly or monthly basis. Therefore,
monitoring data are reasonably representative of temporal
variation. Monitoring for minors can be less frequent and
therefore less representative.
Utility in trend assessment Fair - It is impossible to assess trends on an individual
facility basis where time series data exist. However,
national trend assessment is difficult because PCS has not
been fully supported in the past. With proposed
improvements to the system, and better participation by
States, capability to assess trends will Improve in the
future.
Relation to ultimate impact Fair - Loading estimates do not directly relate to ultimate
water quality impacts. However, correlations have been
observed between load reductions and improvements in
biological community structure and other measures of
water quality.
Related factors Important - For useful interpretation of loading trends,
It Is critical to collect ancillary data characterizing levels
of industrial production, changes in treatment processes,
increases in service areas, etc.
Scientific defensibility Good - Load reductions have been correlated to
improvements in water quality.
46
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VII. LOADINGS
EVALUATION CRITERIA
SensitMty to chance Good - Loads generally directly reflect changes In
Industrial production levels, Improvements or faIlures In
treatment, etc.
Relationsh to risk Poor - It is difficult to directly relate loads to risk.
Monitoring data to support loading estimates for toxic
compounds of greatest concern frequently are not available.
Cost to collect and analyze data Moderate - Because self-monitoring and compliance
monitoring systems for the National Pollutant Discharge
Elimination System (NPDES) are already in place,
monitoring and analysis costs are already budgeted by
facilities and States. Increased toxics monitoring Is
expensive. PCS would have to be modified to allow
computation of loadings.
Relationshic to existino oroarams Good - DMR reporting is well established, supported and
continually being improved. There is a clear connection
between load estimates and effectiveness of point source
control programs.
Presentation value Good - Concept of pollutant loadings is generally accepted
and understandable to government decislonmakers and
public. Status and trends can be graphically portrayed on
charts and maps.
47
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Figure Vli.1
Availability of
PCS Data for Making Point Source
Loading Estimates
Percent of DMR Forms from Major
(4th Quarter of
Facilities
FY 1989)
Entered Into PCS
1Ib
Source: Office of Water Enforcement Support Branch
Note: data for U.S. Territories not shown
DMR Forms Entered
90%tolOO%
80% to 90%
50% to 80%
10% to 50%
Missing Data
E
48
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Figure ViI 3
PCS Example - Three-Dimensional Map Displaying
Total Suspended Solids (TSS) Loadings
Across Illinois (1988)
hO
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50
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Vifi. SUMMARY CHARACTERISTICS OF PROPOSED INDICATORS
IdIt
Deelgnated Use
and Attainment
of “Flshablel
Swimmable”
Evaluation
Stf n
‘Data collection system already laplace ‘At piesant. cannot housed to
‘Cunpuserhod fremework evahate tsatth
‘Low osat to ‘-. . . and Improve ‘lnccesk es and lack of stauderdizadon
‘Of primary interest to majority of public •lnxnsutant within state from one reporting
‘Eaiily Understood cycle to the next
‘Mine ocusiseacy ladafinidons o E m.
‘loses ’. iniofreackotunberorother
geo.retermaed data “
‘mores’. In the use of WBS
se a ls
Shellfish
Harvest Area
Clssslfleatlcsis
‘Data collected for over 20 yeaii ‘Variations lastato4oatate irgapretadonof
‘Data collection baa bean fairly consistait c1assillouti
‘Bully understood by ganeral publes •n sI _1 fur ruasma not
v y in cleuiflc
Ccsrelating with otheruraritoring data
(arab as NOAA Munel Watab data)
related to water quality changes
Trophlc Status
of Lakes
.Dssa collection system already laplace •Reglcwl diffezarces limit national
‘Reper required byCWA 314(a) ceanparlalces
.&tehbas ” in order tobo able to
evah3ste t rmth
4ui a n t iflcallydefanEble’ ” ”
‘The atmiber of lakes evaluated fluctuates
‘Repeal
Computerleed framework
‘Laker are mmitored too infreq .terlly to
derive tr
‘In 305(b ), rq,onboth ntmiber of laker aed
lake ameagu
Tonics In Fish
and Shellfish
USPWS NCBP
‘L.Tcollectlon system t o place
‘flerida established
.Cunputurizcd data collection
‘Of major interest to PWS
‘Only for rivers arid streams
‘LImited number of chemIcals tested
‘Actual ecological Imp’ ’ ’ of fish and
‘Plan to expand to esorarier
‘Looking to Include new tozicanra
‘May include USGS sites and perhaps
NOAA’s Mussel Watch sites
a ’s a subject of
conuoversy
‘Consistantnaticowrde .atsplmg
‘Differant fish it different locations
.Cocrdinate data collection with ud
‘Good umd analysis
‘Not useful for lwman health
sources
NOAA NS&T
Benthic
Surveillance
‘Rave arotillary information on
s.* . Ii at sites and fish
abnormalities
•Spazlal and Ternipccaily rupteserntativo
cortaidoradoce
‘Not point source specific
‘Develop cantralloed database
‘Develop protocols onruonitoring to
inorease compessblity with other
seanc, data
‘Comutaritsalianwide sampling
.C a nonnela re info with data
Not point souico specific
‘Sane as shove
NOAA NS&T
Mussel Watch
•Spatial and Taiporally representative
•Lo .- ’ ’i around known and suspected
‘One tone only study
•Repeat suidy to aaem Nugtaraa to
around
and
fw
sousces
‘No trends
plane
scum,
to
EPA National
‘Can thaw conclusions on impacts
‘Not spatially or leanporally rep.
bate-tasted
Bsi nuladon
‘Can develop information on
4destify sine to
as pal
Stt a ly
b .n ve rnulatio n
of nationwIde med study
‘Being dose at state level
.Vanea from state to state in species.
‘Change in 305(b) to provide
sr wmzsd r ,ults
•Used inseam. too tuesonant
location. chailcals, puapose and
Tissue Residue
‘Related to health advisorres
anotmt of testing
system
Dati Collected
‘No data storage with easy retrieval
.Develop agr” onmoniloring
by States
protocols to inorease comparabilIty
B lo logkml
Community
‘Fish Integrate impacts over whole sneani
‘Bivalves are excellent indicator of
•Reiatively limited amount of
biouicriitering being carried onas
•Inorease guidance to state in tema of
bow to do c —”” ’ t ’y analyses and
Measures
stress
pat of water quality analyses
what to do with the information
of
•Reightaned interest in states and regiona
•Resource constraints
cuassutmily
•C .rna y data is necessary
mrplemant to physicsiJ1i . nvt taling
‘Different staler can use systems that we
No centralized database
analyser part 305(b) reports
appropriate to theIr cn.
Pollutant Loading
‘Data collection and reporting in place
.T .it. 4nns on availability and quality of dat
‘Require permitted facilitiea to report
Estimates from
‘Spatially and tmnporilly representative
‘Little data available for toxic compounds
“ ‘ual and annual
of loath
PoInt Soarces
Good correlation between pollutant k &nga
‘Cucrent data manageansel system (PCS) can
‘Modify to computation
levels and water quality
not compute loads
‘Additional data collection would be cosdy
51
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52
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IX. CONCLUSIONS AND RECOMMENDATIONS
1. The shellfish harvest area classification data available from the National Oceanic
and Atmospheric Administration (NOAA) could be incorporated into an EPA
indicator reporting process in the near term.
2. It would be most efficient and logical for the Office of Water (OW) to use the
State 305(b) reports as the primary vehicle through which it develops data on
indicators.
3. The consistent use of the Waterbody System and individual reach numbers by the
States should be encouraged.
4. In the long-term, there are some additional monitoring and coordination activities
that the Agency, other Federal Agencies, and the States should consider to
develop more meaningful indicators.
5. EPA should actively encourage State programs designed to implement measures of
biological community well-being.
6. If it is desired that indicator data be used for national trend assessment, the Office
of Water (OW) and State water quality Agencies might reconsider a monitoring
strategy in which each State returns to a subset of fixed monitoring stations on
regular intervals to permit trend reporting on a few indicators.
53
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54
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