Tell Me More About Streams, Rivers, Lakes and Ponds

Disclaimer: These digital water quality classifications are an unofficial version of the State's water quality classifications. For the official version please refer to Title 6 of the Official Compilation of Codes, Rules and Regulations of the State of New York (6NYCRR) Part 800 et seq . The water quality classifications have been developed by the Department of Environmental Conservation, Division of Water from the most current sources available. Where there were inconsistencies in the maps the most current representation has been used. These data have not been submitted to the Department of State and they are not official classifications. However, they are largely consistent with the official regulations. Therefore, the public should not make any business decisions and/or financial commitments based on the water quality classification data until they have secured the necessary permissions from the Department of Environmental Conservation.

These maps show the water quality classifications of New York’s lakes, rivers, streams and ponds, collectively referred to as water bodies. All water bodies in the state are provided a water quality classification based on existing, or expected best usage, of each water body or water body segment.

The following list provides summarized definitions of classifications only. See Classifications – Surface Waters and Groundwaters for complete definitions .

  1. The classifications A, AA, A-S and AA-S indicate a best usage for a source of drinking water, swimming and other recreation, and fishing.
  2. Classification B indicates a best usage for swimming and other recreation, and fishing.
  3. Classification C indicates a best usage for fishing.
  4. Classification D indicates a best usage of fishing, but these waters will not support fish propagation.
  5. Classification SA (marine waters) indicates a best usage for shellfishing for market purposes, swimming and other recreation, and fishing.
  6. Classification SB (marine waters) indicates a best usage for swimming and other recreation, and fishing.
  7. Classification SC (marine waters) indicates a best usage for fishing.
  8. Classification I (marine waters) indicates a best usage for secondary contact recreation, and fishing.
  9. Classification SD (marine waters) indicates a best usage for fishing, but these waters may not support fish propagation.

Waters with classifications AA, A, B and C may be designated as trout waters (T) or suitable for trout spawning (TS). These designations are important in regards to the standards of quality and purity established for all classifications. See the DEC Rules & Regulations and the Water Quality Standards and Classifications page on the NYSDEC web site for information about standards of quality and purity.

When you use the Environmental Resource Mapper to identify a classified water body, your selection results will return three pieces of information:

Note that not all water bodies appear on these maps. However, the missing water bodies will always have a classification. Water bodies that do not appear on these maps and have flow all year (perennial flow) have the classification of the water body they flow in to. Water bodies that do not appear on these maps and have flow only seasonally (intermittent flow) have a classification of "D." Since it may be difficult to determine if a water body has perennial or intermittent flow, please contact your DEC Regional Office if there is any doubt. DEC has the final authority to determine if a water body has perennial or intermittent flow.

For additional information about NYSDEC's Water Quality Classification program, please see the Water Quality Standards and Classifications page on the NYSDEC web site.

Permit Information

Under New York State’s Environmental Conservation Law (ECL), Title 5 of Article 15, certain waters of the state are protected on the basis of their classification. Streams and small water bodies located in the course of a stream that are designated as C (T) or higher (i.e., C (TS), B, or A) are collectively referred to as "protected streams". A Protection of Waters Permit is required to physically disturb the bed or banks of any stream with a classification standard of C (T) or higher.

Small ponds and lakes with a surface area of 10 acres or less, located within the course of a stream, are considered to be part of a stream and are also subject to regulation under the stream protection category of Protection of Waters.

A Protection of Waters permit is also required when excavating or placing fill in navigable waters of the state, below the mean high water level, including adjacent and contiguous marshes and wetlands. Navigable waters include lakes, rivers and other waterways and water bodies on which water vessels with a capacity of one or more persons are operated or can be operated. Waters that are surrounded by land held in single private ownership at every point in their total area are exempt from this requirement.

For additional information about NYSDEC's Protection of Waters Program, please see the Protection of Waters Program page on the NYSDEC web site.