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NYS Section 305(b) Water Quality Report

Water quality reporting under the Clean Water Act (CWA) Section 305(b) and Section 303(d) are highly visible ways of communicating to the public about the health of the nation's waters. Under Section 305(b), states are required to periodically report on the quality of all water resources in the state and whether these waters are fully supporting water supply use, recreation activities and aquatic life. Section 303(d) requires states to identify the subset of state waterbodies where water quality standards are not met and where uses are not supported. The Section 303(d) List includes those waters (and associated pollutants) that do not support uses, and which require development of a Total Maximum Daily Load (TMDL) strategy. Because the Section 303(d) List of Impaired/TMDL Waters is concerned with only impaired waters - and within the universe of impaired waters, only those impaired waters that can be addressed with a TMDL strategy - the Section 305(b) Report provides a more comprehensive assessment of statewide water quality.

Presented here is an Executive Summary of key findings in the most recently (2012) issued New York State Section 305(b) Water Quality Report. The remainder of the report can be accessed through links in the Table of Contents that follows the Executive Summary.

Executive Summary

The 54,471 square miles of New York State are rich in water resources. Freshwater resources include more than 87,000 miles of rivers and streams, nearly 7,900 lakes and ponds totaling about 690,000 acres (not including Great Lakes), and over 400 miles of Great Lakes coastline. The marine waters of the state include more than 1,530 square miles of estuaries, as well as about 120 linear miles of Atlantic Ocean coastline. New York State is the only state in the country that has some of all five designated waterbody types. Additionally, about six million residents draw drinking water from abundant groundwater resources in the state. Water quality in a majority of these waters supports all intended uses. However, there are waterbodies that are affected by some level of water quality impact, use impairment, or are otherwise threatened by various human activities.

The New York State Department of Environmental Conservation (NYSDEC) Division of Water maintains an extensive inventory/database of these waters. The Waterbody Inventory/Priority Waterbodies List (WI/PWL) provides waterbody-specific summaries of water quality conditions, tracks the degree to which the waterbodies support (or do not support) a range of uses, and monitors progress toward the identification and resolution of water quality problems, pollutants and sources. Information from the WI/PWL serves as the basis for this Clean Water Act Section 305(b) Water Quality Report.

Water Quality Assessment Map

An overview map (PDF) (3.73 MB) has been prepared showing current water quality conditions in New York State. The map shows how the waters of the state correspond to five assessment categories:

  • Impaired Waters
  • Waters with Minor Impacts
  • Waters with No Known Impacts
  • Waters Needing Verification of Impact
  • Unassessed Waters

Overall New York State Water Quality

Overall use support for various types of waterbodies in New York State is as follows:

Pie chart showing number of rivers/streams in different water quality assessment categories

Rivers and Streams: Two-thirds (66%) of the 87,124 miles of New York State river and stream miles are assessed. Approximately 7% are categorized as being Impaired Waters that do not fully support their designated use, with about 6% of river/stream miles on the 2012 New York State Section 303(d) List. About 17% of river/stream miles are assessed as having Minor Impacts or Threats but still support uses, while nearly 7% of these waters Need Verification of impact to determine standards attainment/use support. One-third of rivers/stream miles have No Known Impacts. About 34% percent remain unassessed; this percentage of unassessed waters is down from 45% in 2008, but down only slightly (from 35%) since 2010.

Pie chart showing number of lakes/reservoirs in different water quality assessment categoriesLakes and Reservoirs: Nearly half (46%) of New York State lake and reservoir acres are categorized as Impaired Waters that do not fully support designated uses; 32% of state acres are included on the 2012 Section 303(d) List. However, much of the lake impairment in the state is due to a few large waterbodies that support most uses but have lakewide restrictions for a specific use. For example, while Lake Champlain supports drinking water use and a variety of recreational activities, a limited fish consumption advisory for the entire lake accounts for over one-quarter of the impaired lake acres in the state. About 28% of lake acres have Minor Impacts or Threats but still support uses, while 3% of these waters Need Verification of impact to determine standards attainment/use support. Only 7% of lake acres have No Known Impacts. About 16% percent remain unassessed; this percentage of Unassessed waters is down from 20% in 2008, but about the same as in 2010.

Pie chart showing number of estuary waters in different water quality assessment categoriesEstuary Waters: About 46% of New York State estuary waters are categorized as Impaired Waters that do not fully support uses; most (36%) are on the 2012 Section 303(d) List. Most (over 90%) of the Impaired Waters are the result of fish consumption; shellfishing impairment occurs in about one-quarter of Impaired Waters. Other uses such as public bathing, recreation and aquatic life are supported in over 90% of estuary waters. About half (48%) of estuary waters have Minor Impacts or Threats but still support uses. Only about 11% of estuary waters have No Known Impacts.

Great Lakes Shoreline: The New York State Great Lakes shoreline is categorized as being Impaired Waters that do not fully support designated uses, with all of these shore miles included on the 2012 New York State Section 308(d) List due to fish consumption advisories.

Atlantic Ocean Coastline: Most (92%) of New York State ocean coastal waters are considered to have No Known Impacts and support all designated uses.

Top Ten Water Quality Issues in New York State

The NYSDEC Water Quality Assessment Program has identified the Top Ten most prevalent causes/sources of water quality impact/impairment in the assessed waters of New York State. These are:

  • Urban Stormwater Runoff
  • Aging/Inadequate Wastewater Treatment Infrastructure
  • Nutrient Eutrophication
  • Atmospheric Deposition and Acid Rain
  • Legacy Pollutants in Sediments and Fish
  • Atmospheric Deposition of Mercury
  • Habitat/Hydrologic Modification
  • Nuisance Aquatic Weed Growth and Invasive Species
  • Pathogen Contamination of Shellfish
  • Inadequate Onsite Wastewater Treatment

The figure below shows the frequency for which a specific cause/source is noted as a significant contributing factor in New York State waters. The figure shows the occurrence of each cause/source as a percentage of all waters assessed as impaired (red) or impacted (yellow).

Bar chart showing the occurrence of causes/sources as percentage of all impaired/impacted waters

Each of these causes/sources is discussed in greater detail in a series of Fact Sheets (PDF) (814 KB). The Fact Sheets outline the nature of the specific cause/source, the significance of the issue, what New York State waters are most susceptible and what is being done to address the problem.

Waterbody Inventory and Assessment Coverage

Originally the New York State water quality assessment effort focused on assessing waters with known or suspected water quality problems. However beginning in the mid-1990s and continuing through the present, that focus has shifted to producing a more comprehensive and representative assessment of all the waters of the state. Although the comprehensive assessment goals have yet to be fully realized, considerable progress has been made toward the assessment of 100% of the waters of the state.

Water Quality Trends in New York State

Assessed Waterbodies in New York State
Waterbody Type Amount of Assessed Waterbody Percent of
2002 2006 2010 2012
Rivers/Streams 9,360 mi 48,469 mi 56,269 mi 57,070 mi 66%
Lakes/Reservoirs 250,000 a 561,267a 578,124 a 579,620 a 84%
Estuary Waters 1530 sq mi 1530 sq mi 1536 sq mi 1509 sq mi 100%
Gr. Lakes Shore 457 mi 577 mi 577 mi 592 mi 100%
Ocean Coastline 118 mi 118 mi 118 mi 118 mi 100%

The increase in the number of assessed waters over the past 10 to 15 years can complicate the identification of trends in the quality of New York State waters. Considerable anecdotal and intuitive knowledge, as well as numerous waterbody-specific case studies, reflect remarkable water quality improvement since the passage of the Clean Water Act in 1972. However those improvements are not always reflected in the number of impaired or impacted waters, which typically increase with each assessment. For the most part, this increase in the number of impaired/impacted waters parallels the increase in the number of assessed waters. That is, as more waters are monitored, waters in all categories are likely to increase.

For example, the number of impaired waterbody listings on the New York State Section 303(d) List increased by 5.4% from 828 in 2010 to 873 in 2012. On the surface, this does not suggest progress in improving water quality. However this increase is largely the result of previously unassessed waterbodies that are not necessarily newly impaired, but have only been recently identified as such. This observation is not intended to minimize the importance of these new listings, but to point out that the additions do not necessarily reflect a declining trend in statewide water quality, but rather reflect an increase in the coverage of the monitoring and assessment effort. For additional perspective, note that over the same two year period the number of waterbodies assessed as having no known impacts increased by 44%, from 680 to 977.

A better assessment of water quality trends is the NYSDEC report Thirty Year Trends in Water Quality of Rivers and Streams in New York State, 2004. Since 1972, the NYSDEC Stream Biomonitoring Unit has been using benthic macroinvertebrate communities to monitor and assess water quality in the rivers and streams of New York. Macroinvertebrates are aquatic insects such as mayflies, stoneflies and caddisflies, worms, clams, snails and crustaceans. Because these biological communities have been sampled using the same technique at over 3,000 sites in New York over 38 years, this data lends itself well to determining temporal trends in water quality. The Thirty Year Trends study (entire report available through the "Off Site Link" in the right-hand column at the top of this page) shows a number of trends that have ramifications for the restoration and protection of waters into the future. Among these findings:

  • Severely impacted streams declined from 8% of all streams sampled in the 1970s to 4% in the 1992 to only 1% in 2002. This trend suggests that the most severe water quality impacts are being addressed.
  • From 1972 to 1992, 38% of sites improved while 4% showed declines in water quality (58% did not change significantly). However the results for the period between 1992 and 2002 show 20% of sites improved, while 19% declined (61% did not change).
  • For the improved sites, nearly two-thirds (64%) were attributable to improved wastewater treatment or the elimination of municipal and/or industrial discharges. This reflects a level of success achieved by programs aimed at point source control of pollutants.
  • An examination of the sites where water quality declined over that same period shows that most declines (63%) are attributable to previously non-impacted sites becoming slightly impacted. In is also noted in these cases that most (76%) of the declines were the result of nonpoint source nutrient enrichment.
  • About one-quarter (24%) of the declines in water quality are the result of organic wastes and municipal and industrial wastewater inputs.

These findings also reveal interesting conclusions. It is encouraging to note that most of the declines can be characterized as minor in that they do not represent the lost of uses associated with impaired waters. However they are declines nonetheless, and more needs to be done to maintain high water quality in the state. Also the fact that the cause of the declines is largely a result of nonpoint sources provides additional support for current NYSDEC efforts to address stormwater runoff, agricultural impacts from Concentrated Animal Feeding Operations (CAFOs) and other programs aimed at nonpoint sources.

The secondary cause of water quality declines - organic wastes and municipal and industrial wastewater inputs - suggest aging wastewater treatment infrastructure is a significant source. Many wastewater treatment plants were built of upgraded in the 1970s and early 1980s and are no functioning beyond capacity or at reduced levels of efficiency.

In a larger sense, these findings reflect a need to balance efforts to restore water quality that has been significantly diminished with a comparable effort to provide protection to threatened or higher quality waters. Impaired waters that do not support aquatic life and recreational uses are an obvious priority for today's water quality managers. However additional attention to maintaining good quality waters and protecting waters that are threatened can be a more effective use of limited funding. And such investment may result in fewer water quality problems for future water quality managers.

Table of Contents

Executive Summary

The 2012 Section 305(b) Report Executive Summary (PDF) (3.86 MB) is also available for download.

Water Resources Information

Water Use in New York

Water Supply and Conservation

Water Quality Monitoring and Assessment

Water Quality Monitoring

Waterbody Inventory/Priority Waterbodies List (WI/PWL) Water Quality Assessment

Consolidated Assessment and Listing Methodology

2012 New York State Section 303(d) List of Impaired/TMDL Waters

New York State Water Quality Assessment (PDF) (4.28 MB)

  • Statewide Summary of Designated Use Support
  • Individual Designated Use Summaries
  • Causes/Sources of Water Quality Impact/Impairment

Other Water Quality Assessments

NYS Water Pollution Control Programs


Waterbody Inventory/Priority Waterbodies List (WI/PWL) Basin Assessment Reports