Regulating Clean Water

How do the United States Environmental Protection Agency (EPA) and the

New York State Department of Environmental Conservation (NYSDEC)

regulate Water Quality & cleaning up Stormwater Pollution?


Through the Clean Water Act! As the federal agency, the USEPA sets the guidelines but grants the states the power to tighten and enforce those guidelines * (see the NYSDEC’s Division of Water guidelines). The Clean Water Act Section 305(b) State Water Quality Report provides an overall assessment of water quality in the state. The Clean Water Act Section 303(d) List of Impaired/TMDL Waters outlines waters in the state that have poor water quality and are candidates for specific restoration strategies known as Total Maximum Daily Load (TMDL) plans. A TMDL is the total amount of pollutant the waterbody can receive daily and still meet Water Quality Standards. Therefore, if a TMDL is imposed on a waterbody with a high amount of Phosphorus, that waterbody can carry the daily maximum load, but should that load be exceeded, the waterbody would be in violation of Water Quality Standards. Many TMDLs sources are from polluted stormwater. Implementing TMDL’s and water quality planning are ways to achieve a goal of no net increase of Pollutants of Concern in our communities. When TMDLs are imposed on impaired waters on the 303(d) list, TMDL plans are made to reduce that pollutant loading.

NYSDEC Statewide Ambient Water Quality Monitoring Program (SWMP)

SWMP monitors surface waters and groundwater a rotating basis so that all major drainage basins in the state are monitored over a five year period. The SWMP Program includes the Rotating Integrated Basin Studies program (RIBS) for rivers and streams, the Lake Classification and Inventory (LCI), the Citizens’ Statewide Lake Assessment Program (CSLAP), and the statewide groundwater monitoring program, in coordination with the US Geological Survey.

Through NYSDEC’s RIBS program a variety of assessments are performed (such as aquatic toxicity and biomonitoring) to detect water quality changes over time. The assessments are then posted on the Waterbody Inventory/Priority Waterbodies List (WI/PWL) webpage . See the Lower Hudson River WI/PWL (Hudson- Peekskill Hollow Creek and Saw Mill River watersheds) and Ramapo River WI/PWL lists to read your latest State assessments in Rockland County.

The following are 303(d) listed impaired waterbodies in need of TMDL levels in Rockland County (2016). Their Pollutants of Concern are therefore identified as:

  • Lower Hudson River Drainage Basin : Lower Sparkill Creek: Cause/Pollutant: Pathogens, Oxygen Demand. Suspected Source: Urban/Stormwater Runoff
  • Ramapo/Hackensack River Basin : Congers Lake, Swartout Lake, Rockland Lake: Cause/Pollutant: Phosphorus. Suspected Source: Urban Stormwater Runoff.

Also various tributaries and brooks with a Cause/Pollutant listed as Unknown biological impacts suspected from Urban Stormwater Pollution.

NYSDEC’s Water Quality Classifications & Standards

Waters of New York State are classified by letter according to their specified designated use. For example, a waterbody classified as AA or A is assigned to waters used as a source of drinking water. Classification B indicates a best usage for swimming and other contact recreation, but not for drinking water. Classification C is for waters supporting fisheries and suitable for non-contact activities. The lowest classification and standard is D (NYSDEC). Waters within New York State are assessed to determine their ability to support and maintain their specific designated uses (see CALM below). The letter classifications and their best uses are described in regulation 6 NYCRR Part 701 (see below).

Water Quality Standards are set to protect these uses. A waterbody with Standard listed as B means that water quality standards and criteria specific to Class B waters applies. Waters with classifications A, B, and C that have an additional standard of (T) or (TS) indicate that it may support a trout population or trout spawning. Special requirements apply to sustain trout waters, as they provide valuable and sensitive fisheries resources (NYSDEC).

NYSDEC’s Water Quality Standards & Classifications page is provided here. The letter classifications and their best uses for surface waters are described below, as in regulation 6 NYCRR Part 701 - Classifications--Surface Waters and Groundwaters. Their associated Water Quality Standards are found in 6 NYCRR Part 703 - Surface Water and Groundwater Quality Standards and Groundwater Effluent Limitations .

Letter classes such as A, B, C, and D are assigned to fresh surface waters, and SA, SB, SC, I, and SD to saline (marine) surface waters.

Fresh Waters:

Class A & Class AA : The best usages are: a source of water supply for drinking, culinary or food processing purposes; primary and secondary contact recreation; and fishing. The waters shall be suitable for fish, shellfish and wildlife propagation and survival. This classification may be given to those waters that, if subjected, meet New York State Department of Health drinking water standards and are or will be considered safe and satisfactory for drinking water purposes.

Class B : The best usages are primary and secondary contact recreation and fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival.

Class C : The best usage is fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival. The water quality shall be suitable for primary and secondary contact recreation, although other factors may limit the use for these purposes.

Class D : The best usage is fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival. The water quality shall be suitable for primary and secondary contact recreation, although other factors may limit the use for these purposes. Due to various conditions, Class D waters will not support fish propagation.

Saline Waters:

Class SA : The best usages are shellfishing for market purposes, primary and secondary contact recreation and fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival.

Class SB : The best usages are primary and secondary contact recreation and fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival.

Class SC : The best usage is fishing. These waters shall be suitable for fish, shellfish and wildlife propagation and survival. The water quality shall be suitable for primary and secondary contact recreation, although other factors may limit the use for these purposes.

Class SD : The best usage of Class SD waters is fishing. These waters shall be suitable for fish, shellfish and wildlife survival. In addition, the water quality shall be suitable for primary and secondary contact recreation, although other factors may limit the use for these purposes. This classification may be given to those waters that, because of natural or man-made conditions, cannot meet the requirements for fish propagation.

Class I : The best usages of Class I waters are secondary contact recreation and fishing. These waters shall be suitable for fish, shellfish, and wildlife propagation and survival. In addition, the water quality shall be suitable for primary contact recreation, although other factors may limit the use for this purpose.

Trout Waters:

The symbols (T) or (TS) appearing in the "standards" column means that the waters are trout waters, or trout spawning waters. Water quality standards and criteria specific to trout and trout spawning applies.

Pulling it together !

Using NYSDEC’s Water Quality Classification on the mapping application, click on a waterbody and write down the ‘PARTITEM’. Now go to 6 NYCRR (New York Code of Rules & Regulation) Chapter Index page on NYSDEC’S website. Click on Chapter X- Division of Water. You will now locate and click on your PARTITEM. For example, if your PARTITEM is 856-11, you will click on Part 856, Sparkill Creek Drainage Basin. On the next link click on the ‘Table’ link and locate your item number which is the second number of your PARTITEM. What can you learn about your waterbody? What is the Water Index Number (WIN)? If your PARTITEM is 856-11, your WIN is H-13-3. What is the Class? The Standard? What does this mean?

NYSDEC’s 30 Year Biological Trends Report:

Since 1972, New York State has monitored the health of its rivers and streams by studying the macroinvertebrates living in them. Macroinvertebrates are excellent indicators of overall water quality because they are sensitive to environmental impacts, are abundant in the state's waters, and are less mobile than fish and therefore cannot avoid most discharges in to waterbodies (DEC). NYSDEC’S Water Assessments by Volunteer Evaluators (WAVE) program is an on-going citizen-based water quality program to collect benthic macroinvertebrates from wadeable streams.

View the 30-year macroinvertebrate report in your drainage basin by clicking on the Lower Hudson or the Passaic-Newark basin.

NYSDEC’s Consolidated Assessment and Listing Methodology (CALM) :

As mentioned above, waters within New York State are assessed to determine their ability to support their specific designated uses. The processes used to assess the quality of New York State waters is contained in the New York State Consolidated Assessment and Listing Methodology (CALM) . There are 3 parts of CALM. The Monitoring Strategy provides an overview of the NYSDEC’s statewide water quality monitoring program (SWMP). The Assessment Methodology and Listing Methodology provides further information on best uses and the assessment programs, such as the WI/PWL process.

Macroinvertebrate sampling is a measure used to assess the condition of the waterbody. Waterbody assessments range from non-impacted to severely impacted.

Non-impacted : Very good water quality. Water quality is not limiting to fish survival or propagation. This level of water quality includes both pristine habitats and those receiving discharges which minimally alter the biota.

Slightly impacted denotes good water quality. The macroinvertebrate community is slightly but significantly altered from the pristine state. Water quality is usually not limiting to fish survival, but may be limiting to fish propagation.

Moderately impacted : Poor water quality. The macroinvertebrate community is altered to a large degree from the pristine state. Water quality often is limiting to fish propagation, but usually not to fish survival.

Severely impacted : Very poor water quality. The macroinvertebrate community is limited to a few tolerant species. Water quality is often limiting to both fish propagation and fish survival.

Waterbody Assessments are given an overall category to reflect the most recent status conducted to date (see the Listing Methodology and Assessment Methodology for further explanation).

Impaired Waters: The use of the waterbody (drinking water, recreation, shellfishing, etc., is negatively affected by a pollutant. These waters are candidates for inclusion on the NYS Section 303(d) List of Impaired/TMDL Waters (see also Listing Methodology, separate document). These waterbodies have well documented water quality problems, requiring restoration measures in order for uses to be supported.

Waters with Minor Impacts are waterbodies where lesser water quality impacts are apparent, but where use of the waterbody is still considered to be withstood. Although water quality improvement is desired, protection – rather than restoration – strategies may be more appropriate for these waters. Waters with uses that are suspected of being Impaired are considered to have Minor Impacts until the suspected impairment can be confirmed.

Threatened Waters are waterbodies for which uses are maintained, and no water quality problems currently exist, but where additional efforts to protect waters from potential future impacts would be appropriate, based on declining water quality trends, specific land use in the surrounding watershed, and/or specific uses that make the waterbody more susceptible to water quality threats (e.g., Class AA waters). Targeted, waterbody-specific protection strategies are appropriate for these waters.

Waters with Impacts that Need Verification are waterbodies that are thought to have water quality impact or impairment, but for which there is insufficient documentation to justify additional management actions. Such waterbodies require additional monitoring to determine whether their uses are in fact impacted or impaired.

Waters with No Known Impacts are waterbodies where monitoring data and information indicate that there are no use restrictions or other water quality impacts to uses. Waters with No Known Impact can also include waters with uses that have not been fully documented. This category is appropriate to use even when some, but not all, waterbody uses have been assessed.

UnAssessed Waters are waterbodies where adequate water quality information is not available to evaluate the support of any designated uses.

Stream Life:

Reproduced from NYSDEC's Conservationist for Kids.

* The Stormwater Program falls under EPA's National Pollutant Discharge Elimination System (NPDES) program, and is enforced through NYSDEC's State Pollutant Discharge Elimination System (SPDES). For more information on water programs see EPA Learn about Water , the NPDES permit program page, as well as NYSDEC's SPDES permit program page and SPDES Water Guidance Document page.


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Last updated July 25, 2017