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Top Water Quality Issues

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, as listed below:

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

bar graph of frequency of top ten water quality issues in NY
Frequency of the top ten water quality issues in New York.

This information is drawn from the NYS Waterbody Inventory and Priority Waterbodies List. The WI/PWL is compiled by the NYSDEC Division of Water using monitoring data and information from a number of programs and sources, both within and outside NYSDEC. It contains water quality assessments for just over half of the nearly 5,000 waters identified in the statewide Waterbody Inventory. While not all waters of the state have been fully assessed, the percentages shown by the graph are considered to be representative of the causes/sources of water quality impairment throughout the state.

Each of these causes/sources is discussed in greater detail on the linked web pages and downloadable fact sheets (see above for links). These fact sheets outline the nature of the specific problem, the significance of the problem, which New York State waters are most susceptible to the problem and what is being done to address the problem.

Other Observations and Comments on Causes/Sources

  • Impairments and impacts due to Atmospheric Deposition/Acid Rain may be underestimated due to the large number of smaller (under 6.4 acre) ponds in the Adirondack and Catskill regions that have not been individually assessed but are vulnerable to acid rain.
  • Minor impacts and threats (yellow bar) due to Legacy Pollutants in Sediment/Fish and to Atmospheric Deposition of Mercury are considered to be underestimated as a result of a precautionary statewide fish consumption advisory for these substances that is not easily reflected in this assessment.
  • Inadequate Onsite Wastewater Treatment includes impairments and impacts due to the failure of installed systems, as well as the absence of systems that result in the direct discharge of wastewater from residences in communities where a municipal wastewater system is not available.


More about Top Water Quality Issues:

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