Numeric Criteria Development

The information presented below gives a summary of state progress towards the development of numeric criteria. The information comes from EPA’s “State Adoption of Numeric Nutrient Standards (1998-2008)” report, current water quality standards, program activity measures, and nutrient criteria development plans. Links to the District of Columbia’s Nutrient Criteria Plan and state water quality standards are also provided.

• Existing Numeric Criteria
• Links to the Plan and Criteria
• Milestone Information

Existing Numeric Criteria

S = Statewide    W = For selected waterbody    N ⁄ A=Not Applicable

Note: See Statewide Criteria and Site-specific Criteria tabs for more information.

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Links to Numeric Nutrient Criteria Plan and Existing Nutrient Criteria

Plan:

• Nutrient Criteria Development Plan for the District of Columbia 2005

WQS: District of Columbia Water Quality Standards
District Department of the Environment: Water Quality Regulations & Laws Exit

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Milestone Information

Milestone information updated July 2012.

TN: Total Nitrogen; TP: Total Phosphorus

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Statewide Criteria

The information on this tab shows EPA-approved nutrient criteria for District of Columbia’s waterbodies. The language presented below comes directly from state water quality standards and applies to all waterbodies within the state (unless a waterbody type or designated use is noted). Criteria applicable to specific waterbodies within the state can be found on the “Site-specific Criteria” tab. For more information, refer to the District of Columbia water quality standards.

The following information reflects District of Columbia’s water quality standards posted to the Water Quality Standards Repository as of April 2011 (EPA-approved December 2010).

1104 STANDARDS

1104.1 The surface waters of the District shall be free from substances in amounts or combinations that do any one of the following:

(c) Produce objectionable odor, color, taste, or turbidity;

(e) Produce undesirable or nuisance aquatic life or result in the dominance of nuisance species; or

1104.6 Within tidally influenced Class C waters, concentrations of chlorophyll a in free-floating microscopic aquatic plants (algae) shall not exceed levels that result in ecologically undesirable consequences such as reduced water clarity, low dissolved oxygen, food supply imbalances, proliferation of species deemed potentially harmful to aquatic life or humans or aesthetically objectionable conditions or otherwise render tidal waters unsuitable for designated uses.

1104.8 Unless otherwise stated, the numeric criteria that shall be met to attain and maintain designated uses are as follows (Tables 1 through 3):

Class A - Primary contact recreation
Class B - Secondary contact recreation and aesthetic enjoyment
Class C - Protection and propagation of fish, shellfish, and wildlife

Notes:

² This criterion applies to nontidal waters.

³ Attainment of the dissolved oxygen, water clarity and chlorophyll a water quality criteria that apply to tidal influenced Class C waters will be determined following the guidelines documented in the 2003 United States Environmental Protection Agency publication: Ambient Water Quality Criteria for Dissolved Oxygen, Water Clarity and Chlorophyll a for the Chesapeake Bay and its Tidal Tributaries, EPA-903-R-03-002, April 2003, Region III Chesapeake Bay Program Office, Annapolis, Maryland; 2004 Addendum, EPA-903-R-04-005, October 2004; 2007 Addendum, EPA 903-R-07-003 CBP/TRS 285/07, July 2007; 2007 Chlorophyll Criterion Addendum, EPA 903-R-07-005 CBP/TRS 288-07, November 2007; 2008 Addendum, EPA 903-R-08-001 CBP/TRS 290-08, June 2008; and 2010 Criterion Addendum EPA 903-R-10-002 CBP/TRS 301-10, April 2010.

⁴ At temperatures greater than 29^oC, in tidally influenced waters, an instantaneous minimum dissolved oxygen concentration of 4.3 mg/L shall apply.

⁵ Shall apply to tidally influenced waters only.

Site-specific Criteria

The information on this tab shows EPA-approved site-specific nutrient criteria for District of Columbia’s waterbodies. Criteria on this page apply only to the waterbodies listed below. Criteria applicable to all waterbodies within the state are found on the “Statewide Criteria” tab. For more information, refer to the District of Columbia water quality standards.

The following information reflects District of Columbia’s water quality standards posted to the Water Quality Standards Repository as of April 2011 (EPA-approved December 2010).

None.