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NYS Section 303(d) List of Impaired/TMDL Waters

The New York State Section 303(d) List of Impaired/TMDL Waters identifies those waters that do not support appropriate uses and that may require development of a Total Maximum Daily Load (TMDL). The Section 303(d) List is updated every two years. The current List in effect is the Final 2014 New York State Section 303(d) List of Impaired/TMDL Waters (PDF, 261 KB). (September 2014)

The 2014 NYS Section 303(d) List

The Final NYS 2014 Section 303(d) List was "partially approved and partially disapproved" by USEPA on January 13, 2015. In its letter of partial approval/partial disapproval (PDF, 915 KB), USEPA stated that it approved New York State's listing of all waterbody segments and associated pollutants included in its Proposed Final 2014 Section 303(d) List. However EPA also noted that it was disapproving the State's decision not to list the Jones Inlet/Jones Bay on the South Shore of Long Island for nitrogen.

Pursuant to its partial disapproval, USEPA has opened a public comment period to receive comments on its recommendation to add Jones Inlet/Jones Bay to the State's 2014 Section 303(d) List. After examining comment received during this period, USEPA will make a final determination regarding the listing of Jones Inlet/Jones Bay. The public comment period runs through March 25, 2014. Additional information regarding this EPA action and the federal notice can be found on the Federal Register website (This is an off-site link).

Prior to the USEPA partial approval/partial disapproval, a Draft 2014 Section 303(d) List was made available for public comment for a 45 day period that ended March 14, 2014. After considering comments received from the public, a Proposed Final List was submitted to USEPA prior to the April 1, 2014, date for State submittal of 2014 Lists. Additional discussion during the USEPA review of the List led to other revisions and the re-submittal of a Final List to USEPA in September 2014. Except for the decision to not include Jones Inlet/Jones Bay, this version of the List was found by USEPA to meet the requirements of Section 303(d) of the Clean Water Act and was approved in January 2015. Public comments received during the public notice of the Draft List and other issues raised by USEPA during their review of the List are addressed in a response summary (PDF, 228 KB).


The Federal Clean Water Act requires states to periodically assess and report on the quality of waters in their state. Section 303(d) of the Act also requires states to identify impaired waters, where designated uses are not fully supported. For these impaired waters/pollutants, states must consider the development of a Total Maximum Daily Load (TMDL) or other strategy to reduce the input of the specific pollutant(s) restricting waterbody uses, in order to restore and protect such uses. The waterbody/pollutant listings in the Section 303(d) List are segmented into a number of categories. The various categories, or Parts, of the list include:

  • Part 1 - Individual Waterbodies with Impairment Requiring a TMDL
  • Part 2 - Multiple Segment/Categorical Impaired Waterbodies - Includes Acid Rain Waters, Fish Consumption Waters, and Shellfishing Waters
  • Part 3 - Waterbodies for which TMDL Development May Be Deferred - Includes Waters Requiring Verification of Impairment, Waters Requiring Verification of Cause/Pollutant, and Waters Where Implementation/Evaluation of Other Restoration Measures is Pending

Impaired Waters NOT Included on the NYS 2014 Section 303(d) List

Not all impaired waters of the state are included on the Section 303(d) List. By definition, the List is limited to impaired waters that require development of a Total Maximum Daily Load (TMDL). A list of Other Impaired Waterbody Segments Not Listed (PDF, 95 KB) on the 303(d) List Because Development of a TMDL is Not Necessary is also available. The purpose of this supplemental list is to provide a more comprehensive inventory of waters that do not fully support designated uses and that are considered to be impaired.

There are three (3) categories of justification for not including an impaired waterbody on the Section 303(d) List:

  • Category 4a Waters - TMDL development is not necessary because a TMDL has already been established for the segment/pollutant.
  • Category 4b Waters - A TMDL is not necessary because other required control measures are expected to result in restoration in a reasonable period of time.
  • Category 4c Waters - A TMDL is not appropriate because the impairment is the result of pollution, rather than a pollutant that can be allocated through a TMDL.

2014 Waterbody/Pollutant Delistings

A separate list of waterbody/pollutant combinations that were included on the previous (2012) Section 303(d) List, but that are NOT included on the 2014 List is also available. This list of 2014 Water/Pollutant Delistings (PDF, 16 KB) provides some linkage and continuity between the previous and current Lists. The specific reason why a waterbody/pollutant was removed from the List (i.e., delisting action, reassessment, re-segmentation, etc.) is included in this document. Some of these waterbodies/pollutants (specifically, those that have been delisted but that remain impaired) also appear on the list of Other Impaired Waterbody Segments Not Listed Because Development of a TMDL is Not Necessary.

All Impaired Waters

A searchable, sortable spreadsheet of all impaired waters/pollutants is also available. The All Impaired Waters List (Excel, 322 KB) includes both Section 303(d) List waters, as well as Category 4a, 4b and 4c waters that are impaired but not included on the Section 303(d) List.

Consolidated Assessment and Listing Methodology

An outline of the process used to monitor and assess the quality of New York State waters is contained in the New York State Consolidated Assessment and Listing Methodology (CALM). The CALM describes the water quality monitoring, assessment and listing process in order to improve the consistency of assessment and listing decisions. Two components of the CALM, the Assessment Methodology (PDF, 229 KB) and Listing Methodology (PDF, 170 KB), were both used in compiling the Final 2014 Section 303(d) List.

NYSDEC is currently conducting a review and revision of its CALM documents. An initial draft of a Revised Assessment Methodology (PDF, 357 KB) was also made available for comment with the Draft 2014 List. Both an updated Assessment Methodology and Listing Methodology are expected to be finalized for use during the next (2016) Section 303(d) Listing cycle.

Additional information regarding the NYSDEC Water Quality Assessment Program, including the Waterbody Inventory/Priority Waterbodies List assessments and Section 305(b) Water Quality Reporting can be found on the NYSDEC website.