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Legend Information For Watershed Matrix And Maps

For each Hydrologic Unit Code (HUC) area, the following information is presented on the maps and summarized in the matrix table. The ranking factors will determine the category assigned to each HUC area as the Unified Watershed Assessment process continues. On each map, ranking factors that apply to that specific HUC area are starred.

Watershed Statistics:

Miles of streams and square miles of drainage area; number of sites monitored (see monitoring, below); length of Priority Waterbody List (PWL) segments requiring Total Maximum Daily Load (TMDL) assessments of specific pollutants, in miles; number of waterbodies on the (PWL).

Wetlands (Article 24): includes

all those wetlands that have been mapped pursuant to the state's Freshwater Wetlands Act, in acres. Outside the Adirondack Park, this includes wetlands greater than 12.4 acres in size, or smaller wetlands of unusual local importance (typically, 50-60% of the resource). Inside the Adirondack Park, all wetlands greater than one acre in size are mapped, although maps for all watersheds inside the Park are not yet complete.

Agricultural Runoff Potential -

This factor is from the Index of Watershed Indicators and represents the potential for runoff based on soils information on a scale of 1 (least potential) to 3 (highest potential).

Major Waters:

This informational list identifies some of the stream and lake segments within a hydrologic unit. The list was derived from the Index of Watershed Indicators (IWI) that can be found at the EPA web site at www.epa.gov/SURF on the Internet.

Ranking Factors:

Water Quality Factors

Priority Waterbodies List (PWL)

- This is a list of surface waters determined by NYSDEC staff, with public input, to have their uses precluded, (P) impaired, (I) stressed or threatened. The addition of a corresponding aquifer list is in progress. Some reasons for PWL inclusion that are identified in the Unified Watershed Assessment include:

  • Priority Waterbodies List (PWL) - TMDL These are priority waters in New York State identified for total maximum daily load (TMDL) development. As required by Section 303(d) of the Clean Water Act and 40CFR130.7, states identify waters where required technology pollution controls are not sufficient to attain water quality standards, identify the pollutants causing the standards violation and rank or prioritize the waters for TMDL development. TMDL river segments = red line graph
  • Priority Waterbodies List (PWL) - Acidification: As a result of acid deposition, many Adirondack (and some Catskill) lakes and streams are incapable of supporting native communities of aquatic life.
  • Priority Waterbodies List (PWL) - Fish Consumption advisories: This criterion identifies those areas where fish consumption advisories have been issued by the Department of Health. These result when persistent bioaccumulative contaminants from past discharges have been detected in fish at levels that warrant advisories to protect human health. Map symbol zigzag pink linefor rivers, pink dotfor lakes.
  • Priority Waterbodies List (PWL), other - These water resources are identified based on information indicating that the water quality is being degraded and cannot be fully used as a resource, or have problems that damage their environmental integrity. For the purposes of this report two levels of severity, precluded (P) and impaired (I), are used to identify stream and lake segments that have problems. Precluded segments are those where a classified use of the resource cannot be met. An example of a precluded segment would be a fishing ban based on a contaminant occurrence. An impaired segment is a waterbody that has water quality and/or habitat conditions that frequently limit a classified use. A water body that is subject to bathing restrictions due to combined sewerage overflows would be an example of an impaired segment. Map symbol zig-zag green linefor rivers, green dotfor lakes.
  • Natural Resource Factors (It is important to remember that some of the "water quality" factors discussed above also have profound effects on natural resources)
  • Fish and wildlife population levels: In certain watersheds, populations of fish and wildlife species may not be at desired levels. Examples include goals established by the North American Waterfowl Management Plan at particular focus areas in New York.
  • Habitat alteration: Aquatic habitat, including wetlands and riparian habitat, may be impacted from physical alteration, degradation in quality, or changes in biological composition or diversity, including loss of diversity due to non-native vegetation, and problems stemming from excessive turbidity or nutrients that alter community composition. Many aquatic communities have been hydrologically modified through flood control projects, channelization, dam construction and other forms of physical alteration of the channel, bed, or bank, which results in changes in the aquatic community and its habitat.
  • Endangered species: This criterion includes state and federally endangered, threatened and special concern fish and wildlife species that are listed because of reasons associated with perturbations of the aquatic resource (such as loss of habitat).
  • Flow modification: Due to water withdrawals for water supply and irrigation, and release patterns from hydroelectric generation, base flows are not always met in some waterbodies, which adversely affects the resident aquatic community.

Other Symbols Used on Maps

Biomonitoring - The symbol for biological monitoring locations includes all stations evaluated by staff of the Division of Water as part of the on-going stream macro-invertebrate monitoring program. The total number of stations in NY is 722. Map symbol red circle

RIBS stations - these locations represent water quality evaluations conducted under the Rotating Intensive Basin Studies to verify suspected water quality problems and monitor the overall condition of NY waters through chemical and biological analysis. Map symbol gray triangle

Lakes - light blue star this symbol identifies the location of a lake.

RF3 indicates USGS hydrography coverage of streams at 1:100,000 scale (Reach File 3). Map symbol blue zig-zag line

Primary Aquifers - these areas are presented on the map in yellow to identify the locations of significant ground water availability and usage. The upstate primary aquifers and the Long Island area Magothy aquifer system are identified as significant ground waters to enable them to be placed into Category III - Pristine/Sensitive water resources. Map symbol yellow box