The Potomac River watershed covers 14,679 square miles through four states and the District of Columbia. The main stem also is the source for most of the Districts drinking water. Battery Kemble, Dalecarlia, and Foundry Branch were listed in 1998 for elevated levels of organics and metals in fish tissue and sediment in the Anacostia River. The total maximum daily loads (TMDLs) were approved for the Potomac River tributary parameters identified in the table below on May 24, 2004.
The TMDLs were challenged in Friends of the Earth v. EPA 446 F.3d 140 (D.C. Cir. 2006) because the loads were not expressed in daily loads. Following the case, a settlement agreement was reached between the US Environmental Protection Agency (EPA) and Anacostia Riverkeeper, Friends of the Earth, and Potomac Riverkeeper (Case No.: 1:09-cv-00098-JDB of January 15, 2009). To meet the settlement requirements, EPA will revise the applicable TMDLs to express daily loads. The District Department of the Environment (DDOE) is working with EPA to collect/analyze data and revise the TMDLs for toxic parameters. The table below lists the TMDL water bodies and pollutant pair with the current impairment status in the District’s 2014 Integrated Report. In the table below, those water body/pollutant pairs categorized in 4a will be revised. However, in several water bodies, recent data was insufficient to support an impairment determination, or the samples met water quality standards and therefore the water body/pollutant was removed from the impaired list for a particular pollutant.
Toxic parameters and Impairment Status (2014 Integrated Report)
Battery Kemble
| Arsenic | Copper | Lead | Mercury | Zinc | 4,4' DDD | 4,4' DDE | 4,4' DDT | Chlordane | Dieldrin | Hepatchlorn Epoxide | PAHs | PCBs |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 32 | 32 | delisted | 32 |
Dalecarlia
| Arsenic | Copper | Lead | Mercury | Zinc | 4,4' DDD | 4,4' DDE | 4,4' DDT | Chlordane | Dieldrin | Hepatchlorn Epoxide | PAHs | PCBs |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 31 | 31 |
|
31 | 32 | 32 | 32 |
Foundry Branch
| Arsenic | Copper | Lead | Mercury | Zinc | 4,4' DDD | 4,4' DDE | 4,4' DDT | Chlordane | Dieldrin | Hepatchlorn Epoxide | PAHs | PCBs |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| delisted | delisted | delisted | delisted |
Notes:
Categories reflect the District’s category definitions in the Integrated Report
Category 3 - There is insufficient available data and/or information to make a use support determination.
31 - Previously unlisted, now in category 3 (insufficient information)
32 - Previously in category 4a, now in category 3 (insufficient information)
Category 4a - A State developed TMDL has been approved by EPA or a TMDL has been established by EPA for any segment-pollutant combination.
Delisted - Previously in Category 4a, now unlisted
Black boxes represent parameters not included in TMDLs.
For more information, please see the District’s 2014 Integrated Report.
The 2004 final approved TMDL documents for metals and organics in Potomac River tributaries are included below. The revised documents will be posted when available.
