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Section 305(b) of the Clean Water Act
This report was prepared pursuant to Section 305(b) of the Clean Water Act, which states
(b) (1) Each State shall prepare and submit to the Administrator by April 1, 1975, and
shall bring up to date by April 1, 1976, and biennially thereafter, a report which
shall include—
(A) a description of the water quality of all navigable waters in such State during
the preceding year, with appropriate supplemental descriptions as shall be
required to take into account seasonal, tidal, and other variations, correlated
with the quality of water required by the objective of this Act (as identified by
the Administrator pursuant to criteria published under section 304(a) of this
Act) and the water quality described in subparagraph (B) of this paragraph;
(B) an analysis of the extent to which all navigable waters of such State provide
for the protection and propagation of a balanced population of shellfish, fish,
and wildlife, and allow recreational activities in and on the water;
(C) an analysis of the extent to which the elimination of the discharge of
pollutants and a level of water quality which provides for the protection and
propagation of a balanced population of shellfish, fish, and wildlife and allows
recreational activities in and on the water, have been or will be achieved by
the requirements of this Act, together with recommendations as to additional
action necessary to achieve such objectives and for what waters such
additional action is necessary;
(D) an estimate of (i) the environmental impact, (ii) the economic and social costs
necessary to achieve the objective of this Act in such State, (iii) the economic
and social benefits of such achievement; and (iv) an estimate of the date of
such achievement; and
(E) a description of the nature and extent of nonpoint sources of pollutants, and
recommendations as to the programs which must be undertaken to control
each category of such sources, including an estimate of the costs of
implementing such programs.
(2) The Administrator shall transmit such State reports, together with an analysis
thereof, to Congress on or before October 1, 1975, and October 1, 1976, and
biennially thereafter.
Cover photo courtesy of the National Park Service.
National Water Quality Inventory: Report to Congress
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
JAN 1 6 2009
The Honorable Nancy Pelosi
Speaker of the House
House of Representatives
Washington, D.C. 20515
Dear Madame Speaker:
I am pleased to transmit the Environmental Protection Agency's (EPA) National
Water Quality Inventory: Report to Congress, 2004 Reporting Cycle, as required by
Section 305(b) of the Clean Water Act. This document summarizes, on a national basis,
water quality assessment information reported to EPA by the states. It is a companion to
ATTAINS Database, an interactive, on-line database of state water quality information
which allows users to view assessment findings for individual states, watersheds, and
waterbodies. ATTAINS is available at http ://www.epa. gov/waters/ir.
This Report to Congress finds that the states assessed sixteen (16) percent of the
nation's 3.5 million river and stream miles, thirty-nine (39) percent of its 41.7 million
acres of lakes, ponds and reservoirs, and twenty-nine (29) percent of its 87,791 estuary
square miles. Forty- four (44) percent of assessed river and stream miles, sixty- four (64)
percent of assessed lake acres, and thirty (30) percent of assessed estuary square miles
were found to be impaired for one or more designated uses. Leading causes of
impairment included pathogens, mercury, nutrients, and organic enrichment/low
dissolved oxygen. Top sources of impairment included atmospheric deposition,
agriculture, hydrologic modifications, and unknown or unspecified sources.
EPA and states have embarked on a series of probability-based surveys that are
also discussed in this report. Probability-based surveys complement more traditional
targeted monitoring and assessment programs, and add substantially to our understanding
of water quality conditions at state, regional, and national scales. More information on
the national surveys can be found at
http://www.epa.gov/owow/monitoring/nationalsurveys.html.
I would be pleased to further discuss the contents of this report at your
convenience or your staff may contact Christina Moody at (202) 564-0260.
Sincerely,
Benjamin H. Grumbles
Assistant Administrator
Internet Address (URL) • http://www.epa.gov
R«eyel»d/R«eyelabl« • Printed with Vegetable Oil Based Inks on Recycled Paper (Minimum 20% Postconsumer)
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
JAN 1 6 2009
The Honorable Richard B. Cheney °WATERF
President of the Senate
Washington, D.C. 20510
Dear Mr. President:
I am pleased to transmit the Environmental Protection Agency's (EPA) National
Water Quality Inventory: Report to Congress, 2004 Reporting Cycle, as required by
Section 305(b) of the Clean Water Act. This document summarizes, on a national basis,
water quality assessment information reported to EPA by the states. It is a companion to
ATTAINS Database, an interactive, on-line database of state water quality information
which allows users to view assessment findings for individual states, watersheds, and
waterbodies. ATTAINS is available at http://www.epa.gov/waters/ir.
This Report to Congress finds that the states assessed sixteen (16) percent of the
nation's 3.5 million river and stream miles, thirty-nine (39) percent of its 41.7 million
acres of lakes, ponds and reservoirs, and twenty-nine (29) percent of its 87,791 estuary
square miles. Forty-four (44) percent of assessed river and stream miles, sixty-four (64)
percent of assessed lake acres, and thirty (30) percent of assessed estuary square miles
were found to be impaired for one or more designated uses. Leading causes of
impairment included pathogens, mercury, nutrients, and organic enrichment/low
dissolved oxygen. Top sources of impairment included atmospheric deposition,
agriculture, hydrologic modifications, and unknown or unspecified sources.
EPA and states have embarked on a series of probability-based surveys that are
also discussed in this report. Probability-based surveys complement more traditional
targeted monitoring and assessment programs, and add substantially to our understanding
of water quality conditions at state, regional, and national scales. More information on
the national surveys can be found at
http://www.epa.gov/owow/monitoring/nationalsurveys.html.
I would be pleased to further discuss the contents of this report at your
convenience or your staff may contact Christina Moody at (202) 564-0260.
Sincerely,
Benjamin H. Grumbles
Assistant Administrator
Internet Address (URL) • http://www.epa.gov
Recycled/Recyclable • Printed with Vegetable Oil Based Inks on Recycled Paper (Minimum 20% Postconsumer)
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Table of Contents
Table of Contents
Executive Summary ES-1
Rivers and Streams ES-2
Lakes and Reservoirs ES-2
Bays and Estuaries ES-2
Probability Studies of Water Quality ES-2
Future Reporting ES-3
Background 1
About the Water Quality Assessment and TMDL Information Database
(ATTAINS) 1
Assessing Water Quality 3
Findings 9
Rivers and Streams 9
Lakes, Ponds, and Reservoirs 13
Bays and Estuaries 17
Other Waters 20
Coastal Resources 20
Great Lakes 22
Wetlands 22
Probability Surveys of Water Quality 23
National Coastal Assessment 23
The Wadeable Streams Assessment 26
National Lakes Survey 28
National Rivers and Streams Assessment 29
National Wetland Condition Assessment 30
State-Scale Statistical Surveys 31
South Carolina 31
Indiana 33
Florida 34
Future Reporting 36
References 37
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Table of Contents
List of Figures
Figure 1. Water quality in assessed river and stream miles 9
Figure 2. Top 10 causes of impairment in assessed rivers and streams 11
Figure 3. Top 10 sources of impairment in assessed rivers and streams 12
Figure 4. Water quality in assessed lake acres 13
Figure 5. Top 10 causes of impairment in assessed lakes, ponds, and reservoirs 15
Figure 6. Top 10 sources of impairment in assessed lakes, ponds, and
reservoirs 16
Figure 7. Water quality in assessed bay and estuary square miles 17
Figure 8. Top 10 causes of impairment in assessed bays and estuaries 19
Figure 9. Top 10 sources of impairment in assessed bays and estuaries 20
Figure 10. Findings of the National Coastal Condition Report III 24
Figure 11. Biological quality of the nation's streams 26
Figure 12. Extent of streams rated poor for aquatic stressors, and increase in risk
of poor biology in streams rated poor over streams rated good for
each stressor 27
Figure 13. Sampling locations for the survey of the nation's lakes 28
Figure 14. Sampling locations for the national rivers and streams assessment 30
Figure 15. Summary of statewide condition for Florida rivers and streams (left)
and large lakes (right) 34
List of Tables
Table 1. Major Impairment Cause Categories Used in this Report 5
Table 2. Major Pollutant Source Categories Used in this Report 7
Table 3. Individual Use Support in Assessed River and Stream Miles 10
Table 4. Individual Use Support in Assessed Lake, Reservoir, and Pond Acres 14
Table 5. Individual Use Support in Assessed Bay and Estuary Square Miles 18
Table 6. Traditional vs. Probability-based Assessment Results for Rivers and
Streams in South Carolina 32
Table 7. Traditional vs. Probability-based Assessment Results for Estuaries in
South Carolina 33
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List of Acronyms
List of Acronyms
ATTAINS Assessment TMDL Tracking And ImplementatioN System (Water
Quality Assessment and TMDL Information)
BEACH Act Beaches Environmental Assessment and Coastal Health Act of 2000
EPA U.S. Environmental Protection Agency
FWS U.S. Fish and Wildlife Service
NES National Eutrophication Survey
NLA National Lakes Assessment
NOAA National Oceanic and Atmospheric Administration
NPS National Park Service
PAHs polycyclic aromatic hydrocarbons
PCBs polychlorinated biphenyls
TMDL total maximum daily load
USGS U.S. Geological Survey
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National Water Quality Inventory: Report to Congress
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Executive Summary
This National Water Quality Inventory: Report to Congress, 2004 Reporting Cycle,
prepared under section 305(b) of the Clean Water Act, summarizes water quality reports
submitted electronically by 44 states, 2 territories, and the District of Columbia to the
U.S. Environmental Protection Agency
(EPA) for the 2004 reporting cycle.
These state water quality assessment
findings are contained in EPA's Water
Quality Assessment and Total
Maximum Daily Load (TMDL)
Information database and website,
known as ATTAINS (Assessment
TMDL Tracking And ImplementatioN
System). The ATTAINS database is
available online at the website
http://www.epa.gov/waters/ir.
Summary findings of the 2004 state
water quality reports are presented
below. It is important to note that this
information is for a relatively small
subset of the nation's total waters and
may not be representative of the
waterbodies that were not assessed.
Because many states target their limited
monitoring resources to waterbodies
suspected as being impaired, there may
be a lower percentage of impaired
waters among the non-assessed (and
total) waters than among the assessed
waters. Information about the specific sources and causes of impairment is incomplete
because the states do not always report the cause or source of pollution affecting every
impaired waterbody. In some cases, a state may recognize that water quality does not
fully support a designated use; however, adequate data may be unavailable to document
the specific pollutant or source responsible for the impairment. In addition, EPA made
changes in how specific causes and sources of impairment are categorized for 2004, and
in some cases, these changes may affect how these source and cause findings compare to
findings of previous years. Readers are urged to consult the ATTAINS website for
detailed listings of the causes and sources of impairment reported by the states.
EPA developed the Assessment TMDL
Tracking And ImplementatioN System
(ATTAINS) database and website to
combine two formerly separate sites—the
National Assessment Database (for 305(b)
water quality assessment information) and
the National Total Maximum Daily Loads
(TMDL) Tracking System (for 303(d)
impaired waters information). The ATTAINS
database/website includes state-reported
assessment decisions on the support of
designated uses (such as recreation) in
assessed waters; lists of state waters that
are impaired; the causes of impairment
(such as pathogens); the sources of
impairment (such as agriculture); and the
status of actions (TMDLs) to help restore
impaired waters.
ATTAINS contains this information for each
waterbody assessed by the states and
summarizes key waterbody information by
state, by region, and nationally. If a state did
not provide waterbody-specific information
electronically to EPA by the reporting
deadline, it was not included in this report.
EPA worked extensively with the states to
assist in data submittal.
National Water Quality Inventory: Report to Congress
ES-1
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Executive Summary
Rivers and Streams
This report includes states' assessments of 16% of the nation's 3.5 million miles of rivers
and streams for the 2004 reporting cycle. Of these assessed waterbodies, 44% were
reported as impaired, or not clean enough to support at least one of their designated uses
(e.g., fishing, swimming). The states found the remaining 56% to be fully supporting all
assessed uses. Pathogens, habitat alterations, and organic enrichment/oxygen depletion
were cited as the leading causes of impairment in rivers and streams, and the top sources
of impairment included agricultural activities, hydrologic modifications (e.g., water
diversions, channelization), and unknown/unspecified sources.
Lakes and Reservoirs
This report includes states' assessments of 39% of the nation's 41.7 million acres of
lakes, ponds, and reservoirs during the 2004 reporting cycle. Of these assessed
waterbodies, 64% were reported as impaired and 36% were fully supporting all assessed
uses. Mercury, polychlorinated biphenyls (PCBs), and nutrients were cited as the leading
causes of impairment in lakes. The top sources of pollutants to lakes, ponds, and
reservoirs included atmospheric deposition, unknown/unspecified sources, and
agriculture.
Bays and Estuaries
This report includes states' assessments of 29% of the nation's 87,791 square miles of
bays and estuaries for the 2004 reporting cycle. Of these assessed waterbodies, 30% were
reported as impaired, and the remaining 70% fully supported all assessed uses.
Pathogens, organic enrichment/oxygen depletion, and mercury were reported as the
leading causes of impairment in bays and estuaries. The top sources of impairment to
bays and estuaries included atmospheric deposition, unknown/unspecified sources, and
municipal discharges/sewage.
Probability Studies of Water Quality
EPA and the states have embarked on a series of probability-based surveys (discussed
later in this report) to complement more traditional targeted monitoring and assessment
programs and to add substantially to our understanding of state, regional, and national
water quality conditions. These surveys select sites at random to provide estimates of the
condition of a population of waters throughout a state, region, or the nation. They
describe the percentage of waters in a state or region supporting Clean Water Act goals
and the percentage of waters affected by the stressors included in the study design; this
can help inform protection and restoration priorities. Probabilistic surveys are a cost-
effective approach for tracking changes in condition and stressors across the population
ES-2 National Water Quality Inventory: Report to Congress
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Executive Summary
of waters of the United States. As more states adopt probabilistic monitoring, EPA will
be able to more accurately report on water quality trends. This effort will also help inform
water quality policy and ensure that resources are appropriately targeted. As of 2008, 30
states were participating in probabilistic water quality surveys, and EPA has set a goal of
having the participation of all 50 states by 2011. To date, EPA has provided $65 million
in additional section 106 grant monitoring funds to help the states improve water quality
monitoring programs and implement probabilistic survey designs.
Future Reporting
The states are working to strengthen their water monitoring and assessment programs by
developing long-term monitoring strategies that identify the specific actions needed to
achieve more comprehensive and consistent reporting of water quality conditions. In
addition to the combination of probability-based survey monitoring described above and
more traditional monitoring targeted to waters of interest, the states and EPA have
streamlined water quality assessment and reporting by integrating various Clean Water
Act reporting requirements and facilitating and improving electronic reporting of water
data. These efforts will result in more comprehensive and valid information that can be
easily accessed by water quality managers and the public in a timely fashion and used to
describe water quality on a state, regional, or national scale.
National Water Quality Inventory: Report to Congress
ES-3
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Background
Under section 305(b)(l)(A) of the Clean Water Act, the states, territories, and other
jurisdictions of the United States are required to submit reports on the quality of their
waters to the U.S. Environmental Protection Agency (EPA) every 2 years. Historically,
the states submitted these reports in hardcopy format, and EPA prepared a national
hardcopy report that summarized these findings (see http://www.epa.gov/305b). Under
section 303(d) of the Clean Water Act, the states also biennially provide a separate
prioritized list of those waters that are impaired and require the development of pollution
controls. (To learn more about section 303(d) reporting, visit
http://www.epa.gov/owow/tmdl.)
Beginning with the 2002 reporting cycle, EPA urged the states to combine the reporting
requirements for sections 305(b) and 303(d) into one integrated report and to submit
these reports electronically. EPA encouraged the states to combine these reports because
the integration merges environmental data from a variety of water quality programs,
thereby increasing the consistency of the information. In addition, integrated reporting
presents the public with a more informed summary of the quality of assessed state waters;
provides decision makers with better information on the actions necessary to protect and
restore these waterbodies; and streamlines state reporting burdens by eliminating the need
for two separate reports.
Sixteen of the 44 water quality reports submitted by the states were fully integrated for
the 2004 reporting cycle, and progress toward full integration by all the states is expected
in the coming years. Data for both the integrated and non-integrated state reports are
available on EPA's new Water Quality Assessment and Total Maximum Daily Load
(TMDL) Information database and website, ATTAINS (Assessment TMDL Tracking
and ImplementatioN System). To facilitate the states' efforts to improve integrated
reporting, EPA published reporting guidance in 2005 (U.S. EPA, 2005) and a series of
clarifying memoranda in subsequent years. For more information on integrated reporting,
visit http://www. epa.gov/owow/tmdl/guidance. html#tmdl.
About the Water Quality Assessment and TMDL
Information Database (ATTAINS)
The ATTAINS Water Quality Assessment and TMDL Information database (henceforth
referred to as the ATTAINS database) presents electronic water quality information
submitted since 2002 by the states, territories, and District of Columbia. The ATTAINS
database allows the user to view, via the Internet, dynamic tables and charts that
summarize state-reported data for the nation as a whole, for individual states, for
individual waters, and for the 10 EPA regions. The database shows which waters have
National Water Quality Inventory: Report to Congress 1
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Background
been assessed, which are impaired, and which waters have plans (e.g., TMDLs)
completed to help restore water quality. By displaying data in one location, the
ATTAINS database allows for a more informed summary of the quality of state waters
that have been assessed and provides decision makers with better information on the
actions necessary to protect and restore assessed waters of the United States.
To view the ATTAINS database, users can go to http://www.epa.gov/waters/ir and click
on the map to find summary information and assessment results for specific states, EPA
regions, watersheds, and waterbodies of interest. Users can then select information for a
specific biennial reporting cycle (e.g., 2002, 2004) or select the most recent available
information across multiple cycles. A series of tables and charts also summarizes the
status of assessed waters across the nation.
Comparability of Water Quality Data
Although the data in the ATTAINS database provide a picture of state assessment results, this
information should not be used to compare water quality conditions between states, identify trends
in statewide or national water quality, or compare the impacts of specific causes or sources of
impairment over time. The following are reasons for this lack of comparability:
• The methods states use to monitor and assess their waters, including what and how they
monitor and how they report their findings to EPA, vary from state to state and within
individual states over time. Many states target their limited monitoring resources to waters
they suspect are impaired, or to address local priorities and concerns; therefore, the small
percentage of waters assessed may not reflect statewide conditions. States may monitor a
different set of waters from one reporting cycle to another, or may monitor fewer waters
when state budgets are limited. It is also important to note that six states did not provide
electronic data for the 2004 reporting cycle, and that the lack of data from these states affects
the overall summary statistics.
• The science of monitoring and assessment varies over time, and many states are better able
to identify problems as their monitoring and analytical methods improve. For example, states
are conducting more fish tissue sampling than in previous years. The use of improved
assessment methods to collect better information may result in more extensive and
protective fish consumption advisories, even though water quality conditions themselves may
not have changed.
• For the 2004 reporting cycle, EPA re-evaluated how it grouped sources and causes reported
by the states into larger overall categories (such as Municipal Discharges/Sewage or Metals)
for national reporting purposes. The purpose of this re-evaluation was to more accurately
categorize the source and cause information reported by the states. Some overall source and
cause categories were renamed, and some state-reported sub-categories were moved into
different overall categories compared to the 2002 reporting cycle. (See the section Sources of
Impairment in this report for more information.)
• Under the Clean Water Act, each state has the authority to set its own water quality
standards; therefore, a state's definition of its designated uses (for example, Warm Water
Fishery or Livestock Watering) may differ from definitions used by other states, along with
the criteria against which states determine impairments. (See the section Assessing Water
Quality, below, for more information.)
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Background
For this report, EPA has included ATTAINS data from 44 states, the District of
Columbia, the U.S. Virgin Islands, and Puerto Rico. Pennsylvania, Maryland, Florida,
Oregon, Idaho, Hawaii, the tribal nations, and the island territories of the Pacific did not
provide data electronically that could be used for the 2004 reporting cycle. Although
Pennsylvania, Florida, and Oregon did publish hardcopy section 305(b) water quality
reports, EPA relies on the states' electronic submittal of assessment information as the
source of the water quality findings in this report. Maryland and Hawaii submitted only
303(d) impaired waters lists in 2004 and did not provide information on assessed waters
that were not impaired. Idaho is submitting a combined 2004/2006/2008 integrated report
in 2008. Although only data from the 2004 reporting cycle were used for this report, it is
important to note that the ATTAINS database contains all available waterbody-specific
data reported by the states and territories since 2002.
About half the states conduct their own probability-based surveys (based on statistical
random sampling design) to complement this information and to draw statewide
conclusions about their water resources. EPA fully supports these state efforts to provide
more complete assessments of their waters and to increase the percentage of assessed
waters. Because state-level probabilistic monitoring efforts are in their initial stages in
many states, the results of these state-scale probability surveys, for the most part, are not
included in the 2004 ATTAINS database. EPA expects that the 2008 version of the
database will begin to include these results, and that the Agency will be able to move
toward water quality reports that assess all state waters in the coming years. Such
reporting will provide a valuable complement to current knowledge on the subset of
waters with targeted monitoring.
Assessing Water Quality
The states assess the quality of their waters based on water quality standards they develop
in accordance with the Clean Water Act; therefore, water quality standards may differ
from state to state, but must meet minimum requirements. EPA must approve these
standards before they become effective under the Clean Water Act.
Water quality standards consist of three elements: the designated uses assigned to waters
(e.g., Recreation, Public Water Supply, the Protection and Propagation of Aquatic Life);
the criteria or thresholds that are necessary to protect the designated uses (these criteria
are expressed as numeric pollutant concentrations or narrative requirements); and the
anti-degradation policy intended to prevent waters from deteriorating from their current
condition. Waters may be designated for more than one use. To learn more about water
quality standards, visit http://www.epa.gov/waterscience/standards.
National Water Quality Inventory: Report to Congress
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Background
Designated Use Categories in this Report
The states have different names for the various uses they have designated for their waters. For example,
one state might designate as Class A those waters that are capable of supporting fish species of
commercial and recreational value (e.g., salmon, trout), whereas another state might classify similar
waters as Cold Water Fishery waters. The ATTAINS database groups state-reported uses according to
the following overall categories:
• Fish, Shellfish, and Wildlife Protection and Propagation—Is water quality good
enough to support a healthy, balanced community of aquatic organisms?
• Recreation—Can people safely swim or enjoy other recreational activities in and on
the waterbody?
• Public Water Supply—Does the waterbody safely supply water for drinking after
standard treatment?
• Aquatic Life Harvesting—Can people safely eat fish caught in the waterbody?
• Agricultural—Can the waterbody be used for irrigating fields and watering livestock?
• Industrial—Can the water be used for industrial processes?
• Aesthetic Value—Is the waterbody aesthetically appealing?
• Exceptional Recreational or Ecological Significance—Does the waterbody qualify as
an outstanding natural resource or support rare or endangered species?
Information on which state classifications fit under each of these categories can be found
by clicking on the individual use category name in the ATTAINS database.
After setting water quality standards, the states assess their waters to determine the
degree to which the standards are being met. State water quality assessments are normally
based on six broad types of monitoring data: biological integrity, chemical, physical,
microbiological, habitat, and toxicity. (Examples of the different types of data used to
determine a state's water quality are shown in the following box.) Each type of
monitoring data yields an assessment that must be integrated with other data types for an
overall assessment. Depending on the designated use, one data type may be more
informative than others for making the final assessment.
States tribes and other jurisdictions monitor for a variety of pollutants, or causes of
impairment. Table 1 provides a list of major causes of impairment cited in this report.
National Water Quality Inventory: Report to Congress
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Background
Table 1. Major Impairment Cause Categories Used in this Report
Category
Examples
Cause Unknown—
Impaired Biota
Impairment or degradation of the biological community (e.g., fish,
macroinvertebrates) due to an unknown/unidentified cause
Dioxins
Highly toxic, carcinogenic, petroleum-derived chemicals that are
persistent in the environment and may be found in fish tissue, the
water column, or sediments
Flow Alterations Changes in stream flow due to human activity; includes water
diversions for purposes such as irrigation
Habitat Alterations
Modifications to substrate, streambanks, fish habitat; barriers
Metals Substances identified only as "metals"; also, selenium, lead, copper,
arsenic, manganese, others (in some cases, may include mercury)
Mercury A toxic metal with neurological and developmental impacts; found in
fish tissue, the water column, or sediments
Nuisance Exotic Non-native fish, animals, or plants (e.g., Eurasian milfoil, Hydrilla,
Species zebra mussels) that choke out native species and alter the ecological
balance of waters
Nutrients Primarily nitrogen and phosphorus; in excess amounts, these nutrients
overstimulate the growth of weeds and algae and can lead to oxygen
depletion
Organic Enrichment/
Oxygen Depletion
Low levels of dissolved oxygen; high levels of biochemical oxygen-
demanding substances (e.g., organic materials such as plant matter,
food processing waste, sewage) that use up dissolved oxygen in water
when they degrade
Pathogens Bacteria and pathogen indicators, E.coli, total coliforms, fecal
coliforms, Enterococci', used as indicators of possible contamination by
sewage, livestock runoff, and septic tanks
Polychlorinated
biphenyls (PCBs)
A toxic mixture of chlorinated chemicals that are no longer used, but
are persistent in the environment; used originally in industry and
electrical equipment; primarily found in fish tissue or sediments
Pesticides Substances identified only as "pesticides"; also, chlordane, atrazine,
carbofuran, and others; many older pesticides are persistent in the
environment
Sediment Excess sediments, siltation; affects aquatic communities by altering
and suffocating habitat and clogging fish gills
Toxic Organics Chemicals identified only as "toxic organics"; also, priority organic
compounds, non-priority organic compounds, polycyclic aromatic
hydrocarbons (PAHs), and others; often persistent in the environment
National Water Quality Inventory: Report to Congress
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Background
Types of Monitoring Data
• Biological integrity data. Objective measurements of aquatic biological communities
(usually aquatic insects, fish, or algae) used to evaluate the condition of an aquatic
ecosystem. Biological data are best used when deciding whether waters support
aquatic life uses.
• Chemical data. Measurements of key chemical constituents in water, sediments, and
fish tissue. Examples of these constituents include metals, oils, pesticides, and
nutrients such as nitrogen and phosphorus. Monitoring for specific chemicals helps
states assess waters against numerical criteria, as well as identify and trace the
source of the impairment.
• Physical data. Characteristics of water, such as temperature, flow, suspended solids,
sediment, dissolved oxygen, and pH. These physical attributes are often useful
indicators of potential problems and can have an effect on the impacts of pollution.
• Microbiological data. Measurements of pathogen indicators, such as fecal and total
coliform bacteria, E. coli, and Enterococci. Monitoring of these indicators helps
determine possible contamination by such things as untreated sewage, septic
systems, and livestock or pet wastes, and is often used to determine if waters are safe
for recreation and shellfish harvesting.
• Habitat assessments. Assessments used to supplement and interpret other kinds of
data; includes descriptions of the sites and surrounding land uses, assessment of the
condition of streamside vegetation, and measurements of features such as stream
width, depth, flow, and substrate.
• Toxicity testing. Measurements of mortality of a test population of selected
organisms, such as fathead minnows or Daphnia (water fleas). These organisms are
exposed to known dilutions of water taken from the sampling location. The resulting
toxicity data indicate whether an aquatic life use is being attained. These tests can
help determine whether poor water quality results from toxins or from habitat
degradation.
Where possible, the states, tribes, and other jurisdictions identify the sources of those
pollutants associated with water quality impairment. Point sources are sources that
discharge pollutants directly into surface waters from a conveyance (e.g., a pipe). These
sources include industrial facilities, municipal sewage treatment plants, combined sewer
overflows, and storm sewers. Nonpoint sources are sources that deliver pollutants to
surface waters from diffuse origins (e.g., fields and streets). These sources include urban
runoff that is not captured in a storm sewer; agricultural runoff from cropland and grazing
areas; leaking septic tanks; and atmospheric deposition of contaminants from air
pollution. Habitat alterations, dams, channelization, dredging, and stream bank
destabilization are also significant sources of water quality degradation. See Table 2 for
more information on source categories used in this report.
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Background
Table 2. Major Pollutant Source Categories Used in this Report
Category
Examples
Agriculture Crop production, feedlots (including concentrated animal feeding
operations), grazing, manure runoff
Atmospheric Deposition
The settling of airborne pollution from many diverse sources (e.g.,
factory and automobile emissions, pesticide applications) onto land
or water
Construction
Residential development, bridge and road construction, land
development
Habitat Alterations (Not
Directly Related to
Hydromodification)
Riparian and in-stream habitat modification and loss; filling and
draining of wetlands; removal of riparian vegetation; streambank
erosion
Hydromodification
Industrial
Land Application/Waste
Sites/Tanks
Pond construction; channelization; dam construction; dredging; flow
alterations from water diversions; flow regulation; hydropower
generation; streambank destabilization and modification; upstream
impoundments
Factories, industrial and commercial areas, cooling water intake
structures, mill tailings
Salt storage piles; land application of biosolids; land disposal;
landfills; leaking underground storage tanks
Legacy/Historical
Pollutants
Brownfield sites, contaminated sediments, in-place contaminants
Municipal
Discharges/Sewage
Natural/Wildlife
Septic systems, sewage treatment plants, domestic sewage
lagoons, sanitary sewer overflows, municipal dry and wet weather
discharges, unpermitted discharges of domestic wastes, combined
sewer overflows, sewage disposal
Flooding, drought-related impacts, waterfowl
Recreation and Tourism Golf courses, marinas, turf management, boat maintenance
Resource Extraction
Abandoned mining, acid mine drainage, coal mining, dredge
mining, mountaintop mining, petroleum/natural gas activities,
surface mining
Silviculture (Forestry)
Forest management, forest fire suppression, forest roads,
reforestation, woodlot site clearance
Spills/Dumping
Accidental releases/spills, pipeline breaks
Unknown/Unspecified
Source of impairment is unknown or cannot be specified
Unspecified Nonpoint
Source
Source of impairment is identified as nonpoint, but no further
information available
Urban-Related
Runoff/Stormwater
Discharges from municipal separate storm sewers, parking lot and
impervious surfaces runoff, highway and road runoff, storm sewers,
urban runoff, permitted stormwater discharges
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Background
For the 2004 reporting cycle, EPA reorganized many source categories compared to
previous reporting cycles; therefore, apparent significant increases or decreases in
individual categories (e.g., Municipal Discharges/Sewage) may be attributable to this
reorganization rather than to actual changes in the impact of an individual source
category.
Hundreds of organizations in the United States conduct water quality monitoring,
including state, interstate, tribal, and local water quality agencies; research organizations
such as universities; industries and sewage and water treatment plants; and citizen
volunteer programs. EPA, the U.S. Geological Survey (USGS), the National Park Service
(NPS), and the National Oceanic and Atmospheric Administration (NOAA) are among
the many federal agencies that collect water quality monitoring data. These monitoring
organizations collect water quality data for their specific purposes, and many share their
data with other users, including government decision makers. The states evaluate and use
much of these data when preparing their water quality reports.
The states, territories, and tribes maintain monitoring programs to support several
objectives, including assessing whether water is safe for drinking, swimming, and
fishing. The states also use monitoring data to review and revise water quality standards,
identify impaired and threatened waters under Clean Water Act section 303(d), develop
pollutant-specific TMDLs, determine the effectiveness of control programs, adjust
drinking water treatment requirements, measure progress toward clean-water goals, and
respond to citizen complaints or events such as spills and fish kills.
Nationally consistent probability
To learn more about the water quality monitoring,
surveys are an efficient way to get assessment, and reporting practices of a specific
a good understanding of national state, visit the state's water quality Internet site and
water quality conditions and trends. read tne explanatory and programmatic information
„ i i •,-. included in most reports.
Probability surveys are
scientifically based studies designed to sample water quality conditions at randomly
selected sites that are statistically representative of the population of waters across the
United States. EPA and its monitoring partners have used this methodology to develop a
series of National Coastal Condition Reports (http://www.epa.gov/nccr), which
summarize the findings of the National Coastal Assessment, a probability-based study.
Another probability-based project currently underway is the National Study of Chemical
Residues in Lake Fish Tissue (http://www.epa.gov/waterscience/fishstudy), which is the
first national freshwater fish contamination survey to have statistically selected sampling
sites. EPA also partnered with the states to conduct the probability-based Wadeable
Streams Assessment (http://www.epa.gov/owow/streamsurvey) to determine the
biological condition of small streams in the United States. The Wadeable Streams
Assessment was completed in 2006.
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Findings
Rivers and Streams
The 2004 ATTAINS database summarizes river and stream designated use support
information reported by the states by overall use support and by individual categories of
uses. Waters are rated for overall use support as follows:
Good if they fully support all their designated uses;
Threatened if they fully support all uses, but exhibit a deteriorating trend; and
• Impaired if they are not supporting one or more designated uses.
This report includes states' 2004 assessments of 563,955 miles of rivers and streams, or
16% of the nation's 3.5 million stream miles (Figure 1). Because six states did not
provide specific waterbody data electronically in 2004, the findings of this report address
about 130,000 fewer stream miles than were reported in 2002. The states identified 44%
of the assessed miles as being impaired, or not supporting one or more of their designated
uses. The remaining 56% of assessed miles fully supported all uses, and of these, 3%
were considered threatened (i.e., water quality supported uses, but exhibited a
deteriorating trend).
Total U.S. Streams
3,533,205 Miles*
84%
Unassessed
Assessed Streams
563,955 Miles
3% Good but
Threatened
15,698 Miles
302,255
Miles
246,002 Miles
"Total U.S. river and stream miles based on state 2004 Integrated Reports.
Percents may not add up to 100 because of rounding.
Figure 1. Water quality in assessed river and stream miles.
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Findings
Individual use support assessments also provide important details about the nature of
water quality problems in rivers and streams. Table 3 shows the top five assessed uses in
rivers and streams. The states evaluated support of the Fish, Shellfish, and Wildlife
Protection/Propagation use most frequently, assessing a total of 466,617 stream miles (or
13% of U.S. stream miles) and reporting that 36% of assessed stream miles were
impaired for this use. In addition, the states assessed 303,317 stream miles for the
Recreation use (primary and secondary contact) and found recreation to be impaired in
28% of these waters.
Table 3. Individual Use Support in Assessed River and Stream Miles
Designated Use
Percentage Percentage of Waters Assessed
Miles of Total U.S.
Assessed River Miles Good Threatened Impaired
Fish, Shellfish, and
Wildlife Protection/
Propagation
466,617
13
61
36
Recreation
Agricultural
Aquatic Life Harvesting
Public Water Supply
303,317
200,817
154,746
139,440
9
6
4
4
69
90
56
79
3
<1
4
3
28
10
40
18
a Waterbodies can have multiple designated uses, resulting in an overlap of river and stream
miles assessed.
The ATTAINS database provides more detailed information about the sources and causes
of impairments in rivers and streams, but it is important to note that the information about
specific sources and causes is incomplete because the states do not always report the
pollutant or source of pollutants affecting every impaired river and stream. Although in
some cases states may recognize that water quality does not fully support a designated
use, they may not have adequate data in some cases to document the specific pollutant or
source responsible for the impairment.
It is also important to note that—in an effort to provide clearer and more specific
information—the actual categories of causes of impairment have changed since previous
reporting cycles. For example, the cause of impairment category previously identified as
Metals has now been divided into
, „ , , More information on state-reported causes and
two cause categories, Metals and sources Qf impairment is avaj|ab|e from the ATTA|NS
Mercury; however, some states Water Quality Assessment and TMDL Information
may continue to report mercury database at http://www.epa.gov/waters/ir.
under the Metals category.
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Findings
Similar changes have occurred to the source categories used in this report. For example, a
new source category, Unspecified Nonpoint Source, was created in 2004 to capture
sources previously part of the Unknown/Unspecified category, but for which some
information (i.e., nonpoint source origins) had been identified; therefore, the
Unknown/Unspecified category is somewhat smaller in 2004 than it was in 2002.
Similarly, the 2002 source category Municipal Permitted Discharges has been renamed
Municipal Discharges/Sewage and now captures combined and sanitary sewer overflows;
therefore, this category is larger than it was in 2002.
Figure 2 shows the top 10 reported causes of impairment in assessed rivers and streams.
According to the states, the top causes of river and stream impairment regardless of
designated use were the following:
Pathogens (bacteria), which indicate possible fecal contamination that may
cause illness in people;
Habitat alteration, such as disruption of stream beds and riparian areas; and
Organic enrichment/oxygen depletion, or low levels of dissolved oxygen, often
due to the decomposition of organic materials.
Miles
Pathogens
Habitat Alteration
Organic Enrichment or
Oxygen Depletion
Cause Unknown-Impaired Biota
Nutrients
Metals
Sediment
Mercury
Flow Alteration
Turbidity
10 15 20 25 30 35
Percent of Impaired Stream Miles Affected
Note: Percents do not add up to 100% because more than one cause may impair a waterbody.
Figure 2. Top 10 causes of impairment in assessed rivers and streams.
The listed top 10 causes of impairment (Figure 2) for the 2004 reporting cycle differ from
those reported in 2002. This difference is more likely attributable to reporting changes
(e.g., fewer river and stream miles assessed; improved reporting of the results offish
tissue monitoring; administrative changes in cause category definitions, described above)
than to actual changes in water quality.
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Findings
Figure 3 shows the top reported sources of impairment in assessed rivers and streams.
According to the states, the top sources of river and stream impairment included the
following:
• Agricultural activities, such as crop production, grazing, and animal feeding
operations;
• Hydromodifications, such as water diversions, channelization, and dam
construction; and
Unknown or unspecified sources (i.e., the states could not identify specific
sources).
Other leading sources of impairment in streams included habitat alteration (e.g., loss of
streamside habitat), natural sources (e.g., floods, droughts, wildlife), municipal
discharges/sewage (which includes sewage treatment plant discharges and combined
sewer overflows), and unspecified nonpoint sources.
Miles
Agriculture
Hydromodification
Unknown/Unspecified
Habitat Alteration
Natural/Wildlife
Municipal Discharges/Sewage
Unspecified Nonpoint Source
Atmospheric Deposition
Resource Extraction
Urban Runoff/Stormwater
94,182
61,748
48,957
42,752
39,120
35,301
34,556
27,522
22,691
22,559
0 5 10 15 20 25 30 35 40 45
Percent of Impaired Stream Miles Affected
Note: Percents do not add up to 100% because more than one source may impair a waterbody.
Figure 3. Top 10 sources of impairment in assessed rivers and streams.
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Findings
Lakes, Ponds, and Reservoirs
The 2004 ATTAINS database summarizes designated use support information reported
by the states for lakes, ponds, and reservoirs (hereafter referred to as lakes) by overall use
support and by individual categories of uses.
This report includes the states' assessments of 16.2 million acres of lakes (excluding the
Great Lakes), or 39% of the nation's total 41.7 million lake acres, for the 2004 reporting
cycle (Figure 4). The states identified 64% of assessed acres as impaired, or not
supporting one or more of their designated uses (such as fishing or swimming). The
remaining 36% of assessed acres fully supported all uses, and of these, 1% was
considered threatened. It should be noted that 3.7 million impaired lake acres—about a
third of all impaired lake acres— were reported by one state, Minnesota, due to increased
fish tissue and water monitoring activities addressing mercury.
Total U.S. Lakes
41,666,049 Acres*
61%
Unassessed
25,435
Assessed Lakes
16,230,384 Acres
5,619,221
Acres
I % Good but
Threatened
159,761 Acres
10,451,402
Acres
"Total U.S. lake acreage estimate based on 2004 state Integrated Reports.
Figure 4. Water quality in assessed lake acres.
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Findings
Individual use support assessments provide important details about the nature of water
quality problems in lakes and reservoirs. Table 4 shows the top five uses assessed in
lakes, ponds, and reservoirs. The states assessed 11.8 million lake acres for support of the
Fish, Shellfish, and Wildlife Protection/Propagation use, of which 30% were found to be
impaired. The Aquatic Life Harvesting use (primarily fish consumption) was assessed in
9.4 million acres; of these, 73% were impaired and 1% were considered threatened (i.e.,
water quality is deteriorating). This high percentage of lake, pond, and reservoir waters
impaired for fish consumption is most likely related to changes in how the states report
on waters with statewide fish consumption advisories. For example, in previous cycles,
some states may not have reported waters with fishing advisories as impaired. The
Recreational use (e.g., swimming, boating) was assessed in 8.1 million acres of lakes and
found to be impaired in 26%.
Table 4. Individual Use Support in Assessed Lake, Reservoir, and Pond Acres3
Designated Use
Percentage
Acres of Total U.S.
Assessed Lake Acres
Percentage of Waters Assessed
Good Threatened Impaired
Fish, Shellfish, and
Wildlife Protection/
Propagation
11,770,370
28%
66%
4%
30%
Aquatic Life Harvesting
Recreation
Public Water Supply
Industrial
9,390,396
8,069,018
6,427,687
2,848,335
23%
19%
15%
7%
26%
70%
78%
82%
1%
4%
1%
<1%
73%
26%
20%
17%
B Waterbodies can have multiple designated uses, resulting in an overlap of acres assessed.
The ATTAINS database provides more detailed information on the sources and causes of
impairments in lakes, but it is important to note that the information about specific
sources and causes of impairment is incomplete. The states do not always report the
pollutant or source of pollutants affecting every impaired lake, pond, and reservoir. In
some cases, the states may recognize that water quality does not fully support a
designated use; however, they may not have adequate data to document the specific
pollutant or source responsible for the impairment. The states may then simply report the
cause or source of impairment as unknown or unspecified.
It is also important to note that, in some cases, groupings of causes and sources may have
changed since previous reporting cycles. These changes were made to more accurately
categorize the source and cause information reported by the states.
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Findings
Figure 5 shows the top causes of impairment in assessed lakes, ponds, and reservoirs.
According to the states, the top causes of lake impairment were the following:
Mercury, which has been widely detected in fish tissue, where it may pose a
health risk to people and animals who eat fish;
• Polychlorinated biphenyls (PCBs), which are hazardous chemicals released via
industrial and municipal waste disposal, spills, and leaks; and
• Nutrients, such as phosphorus and nitrogen, which when present in excess can
disrupt lake ecosystems by stimulating growth of undesirable algae and aquatic
weeds.
Acres
Mercury
PCBs
Nutrients
Metals
Organic Enrichment or
Oxygen Depletion
Nuisance Exotic Species
Turbidity
Sediment
Pathogens
Other Cause
5,890,915
2,344,542
1,952,386
1,517,163
1,214,301
960,884
572,003
561,173
528,425
494,230
10
15 20 25 30 35 40 45 50 55 60 65
Percent of Impaired Lake Acres Affected
Note: Percents do not add up to 100% because more than one cause may impair a waterbody.
Figure 5. Top 10 causes of impairment in assessed lakes, ponds, and reservoirs.
Heightened reporting of mercury, PCBs, and metals is largely the result of the reporting
of broad-based fish consumption advisories due to these substances in fish tissue; some
states have begun reporting the extent of waters affected by such advisories and bans. For
example, Minnesota reported 3.7 million acres impaired by mercury (representing 63% of
the lake acres impaired by mercury in the United States) and 1.6 million acres impaired
by PCBs (representing 70% of the lake acres impaired by PCBs in the United States).
Other leading causes of
impairments in lakes include
• , .„ j-11 More information on state-reported causes and
organic enrichment/low dissolved
sources of impairment is available from the ATTAINS
oxygen, nuisance exotic species, Water Qua|ity Assessment and TMDL Information
turbidity, sediment, and database at http://www.epa.gov/waters/ir.
pathogens.
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Findings
Figure 6 shows the top sources of impairment in assessed lakes, ponds, and reservoirs.
According to the states, the top sources of lake impairment were the following:
Atmospheric (or air) deposition, primarily of toxic substances such as mercury,
PCBs, and other metals, from both local and long-range sources;
• Unknown or unspecified sources (i.e., the states could not identify specific
sources); and
Agricultural activities, such as crop production and grazing.
Acres
2,009,363
1,988,588
1,670,513
1,256,542
1,248,432
701,024
583,211
521,250
490,638
485,585
Atmospheric Deposition
Unknown/Unspecified
Agriculture
Natural/Wildlife
Hydromodifi cation
Urban Runoff/Stormwater
Municipal Discharges/Sewage
Legacy/Historical Pollutants
Resource Extraction
Unspecified Nonpoint Source
I I I I
20 25
Percent of Impaired Lake Acres Affected
Note: Percents do not add up to 100% because more than one source may impair a waterbody.
Figure 6. Top 10 sources of impairment in assessed lakes, ponds, and reservoirs.
It should be noted that about one fourth (485,376 acres) of lake acres impaired by
atmospheric deposition were reported by one state, Wisconsin. This is because Wisconsin
reported that all its lake acres are under a fish consumption advisory due to mercury from
atmospheric deposition sources. However, the number of lake acres impaired by
atmospheric deposition does not include lake acres that may be affected by this source in
Minnesota, which reported the largest number of lake acres impaired for mercury and
PCBs. This is because Minnesota did not identify the source of these impairments. It is
likely that the majority of impairment by mercury and PCBs in Minnesota is from
atmospheric deposition. Other leading sources of impairment include natural/wildlife
sources (e.g., droughts, flooding, waterfowl), hydromodification, urban-related
runoff/stormwater, municipal discharges/sewage, and legacy/historical pollutants
(primarily in sediments).
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Findings
Bays and Estuaries
The ATTAINS database summarizes state-reported designated use support information
for bays and estuaries by overall use support and by individual categories of uses.
This report includes states' assessments of 25,399 square miles of bays and estuaries, or
29% of the nation's total estimated 87,791 square miles, for the 2004 reporting cycle
(Figure 7). About 5,000 fewer estuarine square miles were assessed in 2004 than in 2002,
at least in part because several coastal states did not provide electronic data in 2004. The
states identified 30% of assessed square miles as impaired, or not supporting one or more
of their designated uses (e.g., swimming, fishing, shellfishing). The remaining 70% of
assessed estuarine square miles were fully supporting all uses.
Total U.S. Bays and Estuaries
87,791 Square Miles*
71%
Unassessed
62,392
Square Miles
Assessed Bays and Estuaries
25,399 Square Miles
17,721
Square Miles
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Findings
Table 5. Individual Use Support in Assessed Bay and Estuary Square Miles
Square Percentage of Percentage of Waters Assessed
Miles Total U.S.
Designated Use
Assessed Estuarine Miles Good Threatened Impaired
Fish, Shellfish, and
Wildlife Protection/
Propagation
24,338
28%
73%
27%
Aquatic Life Harvesting
Recreation
11,004
9,322
13%
11%
81% <1
87% <1
% 1 9%
% 1 3%
a Waterbodies can have multiple designated uses, resulting in an overlap of square miles
assessed.
State-reported information about specific sources and causes of impairment may be
incomplete because the states do not always report the pollutant or source of pollutants
affecting every impaired bay and estuary. In some cases, the states may recognize that
water quality does not fully support a designated use; however, they may not have
adequate data to document the
specific pollutant or source More information on state-reported causes and
sources of impairment is available from the ATTAINS
responsible for the impairment and Water Qua|ity Assessment and TMDL Information
therefore report the cause or source database at http://www.epa.gov/waters/ir.
as unknown/unspecified.
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Findings
Figure 8 shows the top causes of impairment in assessed bays and estuaries. According to
the states, the top causes of estuarine impairment were the following:
• Pathogens, i.e., bacteria used as indicators of possible contamination by sewage,
livestock runoff, and other sources;
• Organic enrichment/oxygen depletion, i.e., high levels of oxygen-demanding
substances and/or low levels of dissolved oxygen (e.g., organic waste); and
Mercury, a toxic metal found in fish tissue, and, to a lesser extent, in the water
column, often entering the aquatic environment via atmospheric deposition.
Toxic organics, nutrients, pesticides, and metals are also reported as top causes of
impairment for estuarine waters.
Square Miles
I
Pathogens
Organic Enrichment or
Oxygen Depletion
Mercury
Toxic Organics
Nutrients
Pesticides
Metals
PCBs
Other Cause
Turbidity
15 20 25 30 35 40
Percent of Impaired Estuary Square Miles Affected
Note: Percents do not add up to 100% because more than one cause may affect a waterbody.
Figure 8. Top 10 causes of impairment in assessed bays and estuaries.
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Findings
Figure 9 shows the top sources of impairment in assessed bays and estuaries. According
to the states, the top sources of estuarine impairment included the following:
• Atmospheric (or air) deposition, which can bring pollutants such as mercury
from distant locations such as industrial centers;
Unknown/unspecified sources, or sources that cannot be further identified by
the states; and
• Municipal discharges/sewage, which includes septic systems, sewage treatment
plants, and sanitary and combined sewer overflows.
Other leading sources of impairment in bays and estuaries were unspecified nonpoint
sources, other sources (such as sources outside state waters), and industrial sources.
Square Miles
Atmospheric Deposition
Unknown/Unspecified
Municipal Discharges/Sewage
Unspecified Nonpoint Source
Other
Industrial
Natural/Wildlife
Urban Runoff/Stormwater
Agriculture
Hydromodifi cation
i
35 40 45
Percent of Impaired Estuary Square Miles Affected
Note: Percents do not add up to 100% because more than one source may impair a waterbody.
Figure 9. Top 10 sources of impairment in assessed bays and estuaries.
Other Waters
The 2004 ATTAINS database also contains state-reported information on conditions in
coastal shoreline waters, ocean waters, Great Lakes, and wetlands; however, in some
cases, only a small percentage of these resources were assessed in the 2004 reporting
cycle. These waters are discussed below.
Coastal Resources
Coastal resources are identified in the ATTAINS database in two categories: coastal
shorelines (the water immediately offshore, reported in miles) and ocean/near-coastal
waters (i.e., the area of water extending into the ocean or gulf, range not specified, in
square miles). Eight states assessed 1,859 miles of coastal shorelines, or about 3% of the
nation's total 58,618 shoreline miles. The majority of assessed shoreline miles (68%)
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Findings
fully support their designated uses, with 12% of these miles classified as supporting uses,
but threatened (i.e., water quality is deteriorating). In the 32% of shoreline miles not fully
supporting their uses, metals (which could in some cases include mercury) and pathogens
were the leading causes of impairment, and municipal discharges/sewage and industrial
sources were listed as the top sources of impairment.
More information on state-reported causes and
sources of impairment is available from the ATTAINS
Water Quality Assessment and TMDL Information
database at http://www.epa.gov/waters/ir.
To help protect the public at
coastal recreation waters,
Congress passed the Beaches
Environmental Assessment and
Coastal Health Act of 2000
(BEACH Act), which requires
that coastal and Great Lakes states and territories report to EPA on beach monitoring and
notifications to the public of potential health risks. Public notification may include
issuing a beach advisory, warning people of possible risks of swimming due to water
quality problems, or closing a beach to the public. The BEACH Act also requires EPA to
maintain an electronic monitoring and notification database of those data.
For the 2004 swimming season, 28 of 30 coastal states and Puerto Rico reported public
notification actions to EPA. Of the 3,574 beaches that were monitored in 2004, 942
(26%) had at least one advisory or closing. A total of 4,907 beach notification actions
were reported. EPA calculates "beach days" (i.e., the number of beaches multiplied by
number of days in the swimming season) to get a better sense of the extent of the
advisory and closure information. For the 2004 season, EPA determined that there were
584,150 beach days for all of the monitored beaches, and actions were reported about 4%
of the time. EPA is continuing to work to improve the delivery of its beach advisory
information to the public. Visit http://www.epa.gov/beaches for more information on
beach monitoring and notification.
A total of 5,544 square miles of oceans and near-coastal waters, or 10% of approximately
54,120 square miles of oceans and near-coastal waters in the United States, were assessed
by 5 states in 2004. Of the assessed square miles, 88% were identified as impaired.
Mercury was by far the most commonly reported cause of impairment, followed by
organic enrichment/oxygen depletion. Atmospheric deposition was the predominant
reported source of impairment in oceans and near-coastal waters. (It is important to note
that Texas alone assessed nearly 3,879 square miles of oceans and near-coastal waters
and reported that 100% of its assessed square miles are impaired due to mercury in fish
tissue from atmospheric deposition.)
Detailed information on U.S. coastal condition trends is available in the EPA's National
Coastal Condition Report series, which presents the findings of a collaborative effort
between the states, EPA, and other federal agencies to characterize the condition of 100%
of the nation's coastal resources. Section III of this report summarizes key findings of the
National Coastal Condition Report III.
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Findings
Great Lakes
The Great Lakes—Superior, Michigan, Huron, Erie, and Ontario—are freshwater inland
seas of vast importance for water consumption, recreation, fisheries, power,
transportation, and many other uses. Of the eight states bordering the Great Lakes, six
reported on the condition of their Great Lakes shoreline miles.
About 1,070 of 5,521 total Great Lakes shoreline miles were assessed in 2004, and of
these, 93% were reported as impaired. The leading causes of impairment included PCBs,
toxic organics, pesticides, and dioxins. Legacy or historical pollution—primarily
contaminated sediment—was the leading source of shoreline impairment reported by the
states, followed by municipal discharges/sewage.
Wetlands
Wetlands occur where water and land come together for a prolonged period of time and
where saturation of the land with water is the dominant factor determining soil types and
the plant and animal communities living in the soil and on the surface. Wetlands vary
widely because of regional and local differences in soils, topography, climate, hydrology,
water chemistry, vegetation, and other factors, including human disturbance. Included
among the many types of U.S. wetlands are marshes, bogs, swamps, wet meadows,
vernal pools, playas, pocosins, sloughs, peat lands, prairie potholes, and fens.
Wetlands are a critically important resource due to the many benefits they provide to
humans, aquatic life, wildlife, and the environment. Wetlands produce great quantities of
food that attract a huge variety of animal species. They serve as nurseries and habitat for
many game and commercial fish and wildlife species, and they help improve water
quality by intercepting surface runoff and removing, retaining, or filtering out a broad
range of substances (e.g., nutrients, sediments, organic wastes). By storing and slowly
releasing water, wetlands help reduce the impacts of floods and erosion and help
replenish groundwater and stream flow during dry periods. Wetlands are also of great
recreational value to bird watchers, hunters, fishermen, and nature lovers.
Only 10 states provided information on the support of designated uses for 1.8 million
acres of wetlands assessed in their 2004 reports—a tiny portion of the nation's estimated
107 million acres. The states identified 30% of these assessed acres as impaired. Organic
enrichment/oxygen depletion, sediment, and turbidity were the leading causes of wetland
degradation in these six states. Agriculture, unknown/unspecified sources, and
atmospheric deposition were listed by the states as top contributors to impairment.
Section III of this report discusses plans for an upcoming National Wetlands Condition
Assessment.
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Probability Surveys
of Water Quality
EPA, other federal agencies, and the states have embarked on a cost-effective approach to
assess status and track trends in the quality of the nation's waters: probability-based
surveys that complement existing monitoring and assessment programs and add to the
understanding of national, regional, and local water quality conditions. Probability
surveys are designed to yield unbiased estimates of the condition of a whole resource
(such as lakes or rivers and streams) based on a representative sample of waters. These
surveys are designed to answer key questions asked by Congress, the public, and decision
makers, such as the following:
Is water quality improving?
What is the extent of waters that support healthy ecosystems, recreation, and fish
consumption?
• How widespread are the most significant water quality problems?
• Are we investing in restoration and protection wisely?
Several national probability-based studies have already been completed, and several more
are underway. Additional information about these national studies is available at
http://www.epa.gov/owow/monitoring/nationalsurveys.html.
National Coastal Assessment
The National Coastal Assessment surveys the condition of the nation's coastal resources.
The results of these surveys have been compiled into the National Coastal Condition
Report series. The states, EPA, and partner agencies—NOAA, USGS, and the U.S. Fish
and Wildlife Service (FWS)—issued the first three reports of the National Coastal
Condition Report series in 2001, 2005, and 2008. These reports include evaluations of
100% of the nation's estuaries and coastal embayments in the contiguous 48 states,
Puerto Rico, Hawaii, and Southcentral Alaska. Federal, state, and local agencies collected
samples using nationally consistent methods and a probability-based design to assess five
key indices of coastal water health.
The National Coastal Condition Report III finds that the overall condition of the nation's
coastal waters is generally fair and has improved slightly since the 1990s. This rating is
based on five indices of ecological condition: a water quality index (calculated based on
ratings for dissolved oxygen, chlorophyll a, dissolved inorganic nitrogen, dissolved
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Probability Surveys of Water Quality
inorganic phosphorus, and water clarity), a sediment quality index (calculated based on
ratings for sediment toxicity, sediment contaminants, and sediment total organic carbon),
a benthic index, a coastal habitat index, and a fish tissue contaminants index. For each of
these indicators, a score of good, fair, or poor was assigned to each coastal region of the
United States. Ratings were then averaged to create the overall regional and national
scores illustrated in Figure 10, which uses "traffic light" color scoring. Based on the
findings of this survey, 57% of the area of the nation's estuaries and coastal embayments
is in good condition for the water quality index, 6% is in poor condition, and 35% is in
fair condition.
Overall Condition
U.S. Coastal Waters
Overall ,-,
Condition J L
West CoastNy
Good Fair Poor
Good Fair Poor
Overall
Condition
Great Lakes
rail
lition J L
LalcesW
Good Fair Poor)
~®H
Ecological Health
Water Quality Index
Sediment Quality Index
Benthic Index
Overall
Condition .—,
Northeast J L
Coast \J
Good Fair Poor
Overall Condition
Southeast Coast
Overall r-,
Condition J L
Gulf CoastW
Overall Condition
Southcentral Alaska
Good Fair Poor
Overall Condition
Hawaii
[Good Fair Poor] C
* Surveys completed, but no
index data available until
the next report
Overall
Condition
Puerto Rico
[Good
Fair Poor
* Surveys completed, but an
Index rating was unavailable.
Figure 10. Findings of the National Coastal Condition Report III (U.S. EPA, 2008).
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Probability Surveys of Water Quality
Understanding the Value of Probability-based Surveys and the National
305(b) Report
Although some of the findings of the national 305(b) report appear similar to the findings of the national,
probability-based coastal and streams surveys, there are many differences in the scope of these reports
and how they are best used to inform water quality management.
Probability surveys provide consistent environmental indicators of the condition of the nation's water
resources, much as economic indicators report on the health of the nation's economy. Their design
ensures that results represent the population of all waters of a certain type across the United States, and
their consistent sampling methods ensure that results can be aggregated into regional and national
indicators of the health of the resource. The survey results quantify, with documented confidence, how
widespread water quality problems are across the country and estimate the extent of waters affected by
key stressors. This helps set priorities for water resource protection and restoration. Nationally
consistent surveys provide a standardized measure for tracking changes in the condition of the nation's
waters over time and for evaluating, at a broad scale, progress in investments to protect and restore
water quality.
In contrast to the probability surveys, this national 305(b) report summarizes information reported by
states for only a portion of waters (approximately 16% of U.S. river and stream miles, 39% of lake acres,
and 29% of bay and estuarine square miles). It tallies state findings based on data collected using a variety
of sampling methods and parameters; water quality standards and interpretation methods; extrapolation
methods; and time periods. The strength of the 305(b) report is that it provides useful information on
the nature of water quality problems identified by state monitoring programs, documents the amount of
waters assessed and unassessed, and supports the identification of specific waters not meeting water
quality standards; therefore, it helps states set priorities for these waters.
The indices that show the poorest condition are coastal habitat and benthic condition.
Two of the individual component indicators of the water quality index generally show the
best condition—dissolved oxygen and dissolved inorganic nitrogen.
In 2010, EPA and its partners expect to undertake a new survey of coastal waters and to
report survey results in 2012. For more information on the National Coastal Condition
Report series, go to http://www.epa.gov/nccr.
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Probability Surveys of Water Quality
The Wadeable Streams Assessment
The Wadeable Streams Assessment, a survey of the biological health of the nation's
wadeable streams, was launched by EPA and the states to provide a national baseline of
stream water quality based on conditions at approximately 1,300 randomly selected sites
across the conterminous United States. With support from EPA, state water quality
agencies sampled streams using the same methods at all sites. Crews collected
macroinvertebrates to determine the biological condition of streams and also measured
key chemical and physical indicators that reveal stress or degradation of streams. The
Wadeable Streams Assessment reports on four chemical indicators (i.e., phosphorus,
nitrogen, salinity, and acidity) and four physical condition indicators (i.e., streambed
sediments, in-stream fish habitat, riparian vegetative cover, and riparian disturbance).
The Wadeable Streams Assessment found that 42% of U.S. stream miles are in poor
biological condition compared to best-available reference sites in their ecological regions,
25% are in fair condition, and 28% are in good condition (Figure 11). The confidence
level forthese key findings of biological quality is ±2.8%. Five percent of U.S. stream
miles were not assessed because the New England states did not include first-order
streams in the sample design.
1.7%
2.0%
9.5%
Plains and Lowlands
242,26-4 miles
Eastern Highlands
276,362 miles
National
Biological Condition
5.0%
• Good
D Fair
• Poor
D Not Assessed
Figure 11. Biological quality of the nation's streams (U.S. EPA, 2006).
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Probability Surveys of Water Quality
The Wadeable Streams Assessment was designed to examine eight key stressors. The
most widespread stressors observed across the country and in each of the three major
regions are nitrogen, phosphorus, riparian disturbance, and streambed sediments (Figure
12). These stressors can degrade stream conditions for fish and other aquatic life.
Nitrogen and phosphorus are nutrients that, when present in excess amounts, can increase
the growth of algae, decrease dissolved oxygen levels and water clarity, and degrade
stream habitat. Excess streambed sediments can smother habitat for aquatic organisms.
Riparian disturbance is evidence of human activity alongside streams, such as pipes,
pavement, and pastures. The survey found that increases in nutrients and streambed
sediments have the highest impact on biological condition, i.e., streams scoring poor for
these stressors are twice as likely to have poor biological condition as streams that score
in the good range for the same stressors. For more information on the Wadeable Streams
Assessment, go to http://www.epa.gov/owow/streamsurvey.
Relative Risk to
Extent of Stressor Biological Condition
Nitrogen
Phosphorus
Riparian Disturbance
Streambed Sediments
In-stream Fish Habitat
Riparian Vegetative Cover
Salinity
Acidification
Disturbed Condition
Figure 12. Extent of streams rated poor for aquatic stressors and increase in risk
of poor biology in streams rated poor over streams rated good for each stressor
(U.S. EPA, 2006).
R— !3I.8%
HH 30.9%
h
I-
j-i 25.5%
H 24.9%
h Hi 9.5%
I- Hi 9.3%
_Ji 2.9%
J2.2%
I ITI
I I L. \
\—\ 1 2.2
t— Hi.4
L I I T A
H-Hl.4
y— ii.6
HHl.7
3 10 20 30 40 I 2 3 A
Percentage Stream Length in Most Relative Risk
National Water Quality Inventory: Report to Congress
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Probability Surveys of Water Quality
National Lakes Survey
In 2007, EPA and its state partners completed the field-sampling season for the National
Lakes Survey (also known as the National Lakes Assessment [NLA]), a baseline
assessment of the condition of the nation's lakes, ponds, and reservoirs. More than 900
lakes were sampled over the course of a summer for this survey (Figure 13). The
population of lakes to be sampled was comprised of natural and man-made freshwater
lakes, ponds, and reservoirs that were greater than 10 acres in size, at least one meter in
depth, and located in the conterminous United States. The survey does not include the
Great Lakes, the Great Salt Lake, natural saline systems, or treatment and disposal ponds.
In order to examine potential trends in water quality, a representative subset of lakes from
EPA's 1972 National Eutrophication Survey (NES) was included.
• NLA Sampling Site
NLA and NES Sampling Site
Figure 13. Sampling locations for the survey of the nation's lakes.
Key indicators sampled for the National Lakes Survey included the following:
• Trophic indicators, such as in situ temperature and dissolved oxygen profiles,
water chemical quality, nutrient concentrations, chlorophyll a levels,
transparency measured by Secchi disk, turbidity, and color
• Ecological integrity indicators, such as sediment diatom abundance, diversity,
and trends; phytoplankton abundance and diversity; zooplankton abundance and
diversity; shoreline physical habitat conditions; and benthic macroinvertebrate
abundance and diversity
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Probability Surveys of Water Quality
Recreational indicators, such as pathogen (e.g., Enterococci) concentrations,
algal toxin (e.g., microcystins) levels, and sediment mercury concentrations.
Analysis of the survey's data is underway in 2008, and a report on the condition of the
nation's lakes is planned for 2009.
National Rivers and Streams Assessment
EPA is undertaking a survey of the nation's rivers—including the "Great Rivers" of the
United States—and intends to combine it with a second Wadeable Streams Assessment.
In 2008 and 2009, field crews expect to collect data on indicators of the following:
• Ecological condition, such as the abundance and diversity of periphyton,
phytoplankton, benthic macroinvertebrates, and fish
• Recreational value, such, as fecal contaminant concentrations in water and
contaminant residue in fish tissue
Physical habitat condition, such as bank stability, channel alterations, and
invasive species
Water quality, such as basic water chemistry.
The focus will be on wadeable streams in the first year of monitoring and non-wadeable
systems (e.g., rivers) in the second year. Figure 14 shows the locations of the 1,350 new
sites and the 450 sites from the 2006 Wadeable Streams Assessment that will be sampled
for the National Rivers and Streams Assessment. A national report on rivers and streams
is scheduled for 2011. For more information on the National River and Streams
Assessment, visit http://www. epa.gov/owow/riverssurvey/index.html.
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Probability Surveys of Water Quality
• Wadeable Sampling Site
a Non-wadeable Sampling Site
Figure 14. Sampling locations for the national rivers and streams assessment.
National Wetlands Condition Assessment
In 2011, EPA and the states plan to conduct a survey (National Wetlands Condition
Assessment) of the condition of the nation's wetlands, with a report planned for 2013.
EPA and the states are working with the FWS to design the wetlands assessment to
ensure that it effectively complements the FWS Status and Trends reports, which focus
on the distribution of wetlands rather than their condition.
EPA is currently in the research phase of the National Wetlands Condition Assessment
and has identified several significant challenges to designing and implementing a wetland
assessment on a national scale. These include designing the best sample frame and
methods to support a national
report; selecting efficient,
Through the institution of regular probability surveys
scientifically valid indicators; of aN waterbody types, EPA and its partners in the
ensuring that adequate resources states and other federal agencies expect to be able
to cost-effectively assess 100% of the water
resources of the United States and to track trends in
water quality over time. This scientifically based data
will assist in the evaluation of the effectiveness of
pollution-control activities and will greatly improve
our ability to manage the nation's water resources.
are available; maintaining the
resultant data; and building
partnerships to most effectively
use the information gleaned from
the National Wetlands Condition
Assessment.
EPA is coordinating a number of regional pilot projects with the states, academics, and
other federal agencies to test design approaches, field protocols, and indicators. EPA
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Probability Surveys of Water Quality
anticipates that in 2009, the project team will be making initial decisions on condition
indicators and assessment methods that can apply across the nation's wide range of
wetland types. For more information on the National Wetlands Condition Assessment,
visit http://www. epa.gov/owow/wetlands/survey.
State-Scale Statistical Surveys
More than half of the states have begun to implement state-scale statistical or
probabilistic surveys to characterize the full population of a water resource type (e.g.,
streams, lakes). Most of these surveys are of streams and rivers, although lakes, coastal
waters, and wetlands are also surveyed.
The states use probabilistic monitoring designs to develop estimates of water quality
across the entire state, based on a representative sample, and to examine trends in water
quality overtime statewide. Probability surveys can eliminate the risk of generating a
biased picture of water quality conditions; provide information on changes in water
quality overtime statewide; and serve as a cost-effective benchmark of the effectiveness
of the state's water quality program. Also as part of the probability assessment, a state
can produce an estimate of the accuracy of its assessment results. The assessment results
also provide information on whether it would be useful to target certain waters for further
assessment, or if limited resources for water quality assessment can be used more
effectively in other ways.
On the other hand, the states use targeted monitoring to meet state management
objectives such as identifying specific waters that are not meeting water quality
standards, setting priorities for impaired waters, and tracking the restoration of individual
waters. The two assessment approaches (i.e., probabilistic and targeted monitoring) are
not expected to provide the same results because they are designed to achieve different
objectives. Comparing the results of the two approaches is a useful evaluation tool for the
states. For example, the statistical survey's overall description of the full population of
waters provides a useful benchmark for comparing the results of targeted monitoring
activities and can help a state identify potential gaps in its targeted monitoring program.
The following are examples of how some states used probability assessments for water
quality assessment reporting in 2004. It is important to note that for the 2004 reporting
cycle, statewide probability assessments are still a fairly new development, and most
states are only beginning to report their findings.
South Carolina
South Carolina's monitoring program includes a probability-based component to
complement its targeted monitoring activities. Probability-based monitoring is conducted
for streams, lakes/reservoirs, and estuaries. Each year, a new statewide set of probability-
based random sites is selected for each waterbody type. These random sites are sampled
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Probability Surveys of Water Quality
on a monthly basis for one year. The State of South Carolina's 2004 Integrated Report
(South Carolina DHEC, 2004) includes details on site selection. South Carolina provides
tables comparing assessment results from its traditional monitoring program and its
probability-based assessment results for rivers and streams and for estuaries, including a
discussion of the findings.
Table 6 presents a comparison of river and stream data collected using the traditional,
305(b) approach with data collected using a probability-based approach. For rivers and
streams, the traditional approach included data from 630 monitoring stations strategically
located around South Carolina, many of which include biological (macroinvertebrate)
and chemistry data. Approximately 15,300 stream miles—or about half the state's total
29,794 stream miles—were assessed in 2004 using the traditional 305(b) assessment
approach. South Carolina summarized data from a total of 58 randomly located stream
sites for the probability-based assessment conclusions; 29 of these sites were sampled in
2001, and 29 sites were sampled in 2002. These sites represent the total stream miles in
the state, weighted by stream size (i.e., based on the relative proportion of small
headwater streams, second-order or intermediate streams, and larger streams to the
stream resource as a whole).
Table 6. Traditional vs. Probability-based Assessment Results for Rivers and
Streams in South Carolina (South Carolina DHEC, 2004)
Percent of assessed
miles in category—
Estimated percent of
total resource in
category—
Use Support
Category
Aquatic Life Use
Recreational Use
Degree of Use Support
Fully supporting
Partially supporting
Not supporting
Fully supporting
Partially supporting
Not supporting
traditional 305(b)
approach
65.3%
12.1%
22.5%
59.3%
21 .5%
1 9.2%
probability-based
approach
79.0%
5.9%
1 5.0%
49.9%
1 4.6%
35.5%
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Probability Surveys of Water Quality
For its probability-based estuarine condition conclusions, South Carolina summarized
data from 60 randomly located estuary sites—30 sampled in 2001 and 30 sampled in
2002. These sites represent the total estuarine area in the state. Probability-based
approach results were compared to the traditional approach, which assessed 221 square
miles of South Carolina's total 401 square miles of estuaries (Table 7).
Table 7. Traditional vs. Probability-based Assessment Results for Estuaries in
South Carolina (South Carolina DHEC, 2004)
Percent of assessed
square miles in
Estimated percent of
total resource in
category—
Use Support
Category
Aquatic Life Use
Recreational Use
Degree of Use Support
Fully supporting
Partially supporting
Not supporting
Fully supporting
Partially supporting
Not supporting
category — traditional
305(b) approach
68.0%
1 4.4%
1 7.6%
94.1%
4.5%
1.4%
probability-based
approach
75.3%
3.0%
21 .7%
100%
—
—
Indiana
In Indiana, probability-based representative samples are used to determine overall aquatic
life use support as part of the state's rotating-basin approach (i.e., a plan for monitoring a
subset of the state's watersheds on a rotating 5-year cycle, such that in 5 years, all
watersheds have been cumulatively monitored). A stratified random sampling design is
used to generate sampling sites and provide a representative sample set for each basin. A
fish community Index of Biotic Integrity is determined for each sampling location, and
the results of each year's sample data are analyzed to estimate the percentage of stream
miles supporting aquatic life use for each basin. This approach allows the state to make
statistically valid estimates of aquatic life use support for a large geographic area (e.g., a
basin) with a relatively small number of representative samples. For its Indiana
Integrated Water Quality and Assessment Report (Indiana DEM, 2004), Indiana's
probability-based program found that 22,157 stream miles in the state's major river
basins supported aquatic life and 13,168 miles did not support uses, for a total of 35,325
river and stream miles covered by the probabilistic assessment.
Indiana's probability-based sampling design, known as the Watershed Monitoring
Program, allows the state to predict with reasonable certainty what percentage of its
rivers and streams are impaired. An individual stream or stream reach is considered
assessed only when sufficiently detailed monitoring data representative of that stream are
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Probability Surveys of Water Quality
available. According to the state, the principal advantage of the probabilistic monitoring
approach is that it allows the agency to meet the goals of assessing all the waters of the
state (in terms of the overall quality of each basin) while providing data that can also be
used to make waterbody-specific assessments.
Florida
Florida uses a three-tiered approach to monitor surface water quality, ranging from the
general to the specific. Tier 1, or probability monitoring, addresses statewide and regional
questions and is used to develop statistical estimates of statewide water quality based on a
representative sample. This approach allows the state to assess 100% of the waters of the
state over a 5-year period. Tier 2 addresses basin-specific and stream-specific questions
(e.g., to verify waterbody impairment), and Tier 3 addresses site-specific questions, such
as those associated with permits and the development of TMDLs.
The first cycle of the statewide probability assessment through the Integrated Water
Resource Monitoring Network began in 2000 and was completed in 2003. The results for
each basin are aggregated by waterbody type and assessed against water quality targets to
determine the overall health of that type of water in the basin. Florida used this approach
to assess rivers and streams, large lakes, and small lakes (see Figure 15).
17.70%
2.08%
14.70%
13.64%
2.09%
1.42%
5.52%-\
rO.89%
Chlorophyll a Fecal Conforms Dissolved Oxygen Trophic State Index Fecal Coliforms Dissolved Oxygen
"mi
Rivers and Stream
• Meeting Threshold
D Partially Meeting Threshold
D Not Meeting Threshold
Large Lakes
D Meeting Threshold
D Partially Meeting Threshold
D Not Meeting Threshold
Figure 15. Summary of statewide condition for Florida rivers and streams (left)
and large lakes (right) (adapted from Florida DEP, 2004).
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Probability Surveys of Water Quality
Although the Integrated Water Quality Assessment for Florida: 2004 305 (b) Report and
303(d) List Update (Florida DEP, 2004) presents preliminary results for the statewide
probability assessment, it also notes the fundamental differences between this approach
and the basin and stream assessments of the Tier 2 approach. Assessment targets,
parameters monitored, and sample sizes are different between the two assessment
approaches. The results of the probability network should be more representative of
statewide conditions and may be able to shed light on any biases in the basin and stream
assessments due to, for example, the location of monitoring stations. Florida plans to
make comparisons between both types of monitoring approaches as its probability
network continues to evolve.
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Future Reporting
In March 2003, EPA issued guidance describing the basic elements of a state monitoring
and assessment program. In response to this guidance, the states have prepared long-term
strategies that address comprehensive monitoring of all water types, including those for
which little data currently exist. Along with the traditional, targeted monitoring approach,
which describes the condition of individual waters of concern, probability surveys are an
important component of comprehensive water monitoring programs, providing a cost-
effective means of assessing and reporting on status and trends in overall populations of
waters (e.g., streams, rivers, lakes). In the future, 305(b) reports will be able to provide
statistically valid water quality data that are comparable across the states.
The states and EPA are taking steps toward streamlining and improving water quality
monitoring and assessment by integrating monitoring and reporting requirements under
sections 305(b) and 303(d) of the Clean Water Act (see the section Background,
Integrated Water Quality Reporting of this report). EPA has issued guidance to the states
to clarify reporting requirements for the 2008 reporting cycle and has established a goal
that all 50 states and 6 territories and jurisdictions use the integrated reporting format by
2008. EPA continues to promote this comprehensive assessment approach to improve the
states' ability to track both the programmatic and environmental goals of the Clean Water
Act, and ideally, to increase the pace of achieving these important environmental goals.
(See http://www.epa.gov/owow/tmdl for more information on EPA's national water
quality reporting guidance.)
Electronic reporting of water quality information is a continuing EPA priority and
involves a significant commitment at the state and national levels. EPA and the states are
working to ensure that each assessed watershed and waterbody is identified using a
consistent national surface water locational system—the National Hydrography Dataset
(see http://nhd.usgs.gov for more information)—and that electronic reporting continues to
improve. EPA intends to continually adapt and improve the ATTAINS database to reflect
new reporting requirements and the full range of state monitoring activities, including
state-scale probability-based surveys, and will continue to fully support state efforts to
adopt electronic reporting. This commitment to providing more comprehensive, easily
shared water quality information will help managers and the public make more informed
decisions about the future of our waters.
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References
Florida DEP (Department of Environmental Protection). 2004. Integrated Water Quality
Assessment for Florida: 2004 305(b) Report and 303(d) List Update. Florida Department
of Environmental Protection, Division of Water Resource Management, Tallahassee, FL.
Indiana DEM (Department of Environmental Management). 2004. Indiana Integrated
Water Quality and Assessment Report. Indiana Department of Environmental
Management, Indianapolis, IN.
South Carolina DHEC (Department of Health and Environmental Control). 2004. The
State of South Carolina's 2004 Integrated Report. South Carolina Department of Health
and Environmental Control, Columbia, SC.
U.S. EPA (Environmental Protection Agency). 2005. Guidance for 2006 Assessment,
Listing and Reporting Requirements Pursuant to Sections 303(d), 305 (b) and 314 of the
Clean Water Act. U.S. Environmental Protection Agency, Office of Water, Washington,
DC.
U.S. EPA (Environmental Protection Agency). 2006. Wadeable Streams Assessment.
EPA/841-B-06-002. U.S. Environmental Protection Agency, Office of Water,
Washington, DC.
U.S. EPA (Environmental Protection Agency). 2008. National Coastal Condition Report
III. EPA/842-R-08-002. U.S. Environmental Protection Agency, Office of Research and
Development and Office of Water, Washington, DC.
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