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District of Columbia of Water and Sewer Authority, District of Columbia Clean Water Settlement

(Philadelphia, PA - May 20, 2015)  The U.S. Environmental Protection Agency, the District of Columbia (District) and DC Water today announced an agreement to modify a 2005 federal consent decree (CD) allowing DC Water to incorporate green infrastructure in its long-term strategy for curtailing combined sewer overflows (CSOs). 

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The District of Columbia Water and Sewer Authority (DC Water), located in the District of Columbia, owns and operates a combined sewer system, including one waste water treatment plant (WWTP). It should be noted that the District of Columbia (the District) is also being named as a defendant in this enforcement matter.  

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DC Water violated Sections 301, 402 and 504 of the Clean Water Act (CWA) and terms and conditions of its National Pollutant Discharge Elimination System (NPDES) permit. DC Water’s alleged violations include frequent discharges of raw sewage, industrial waste, nutrients, and storm water discharges (i.e. combined sewer overflows (CSOs)) to District of Columbia waterways, including the Anacostia River, the Potomac River and Rock Creek (and ultimately the Chesapeake Bay watershed), and operation and maintenance failures that have resulted in combined sewer overflows.  

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Injunctive Relief

The proposed Consent Decree (Amended Decree or Amendment) in this matter modifies a Consent Decree that the parties entered into in 2005 (2005 Decree). The Amended Decree will provide Defendants an additional five years to complete the work required to address CSOs resulting in an extension of the final compliance date from 2025 to 2030. 

The injunctive relief required under the 2005 Decree is a “grey” remedy that requires the construction of three storage tunnels in the Anacostia River, Potomac River, and Rock Creek Watersheds. Under the Amended Decree, the tunnel in the Anacostia watershed will proceed as originally planned, but Green Infrastructure (GI) may be incorporated into the CSO measures being undertaken in the Potomac and Rock Creek watersheds (potentially reducing or eliminating the need for a storage tunnel in the Rock Creek Watershed, and reducing the size of the storage tunnel in the Potomac River Watershed). In addition, the Amended Decree also includes wastewater treatment projects involving construction at the Blue Plains wastewater treatment facility including a Tunnel Dewatering Pumping Station and an Enhanced Clarification Facility – measures not included in the 2005 Decree. 

These measures are expected to eliminate a substantial percentage of CSOs in each of the three watersheds (98% in the Anacostia watershed, 93% percent in the Potomac River Watershed, and 90% in the Rock Creek watershed). The plant upgrades included in the Amendment are intended to bring DC Water into compliance with the nutrient limits (for nitrogen and phosphorous) in its current NPDES permit. When the injunctive relief in the Amendment is implemented, it is expected to help reduce direct exposure of raw sewage to low income populations in DC Water’s service area. 

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Environmental Justice

Some of the geographic areas (particularly those adjacent to the Anacostia River, and favorably impacted by early pollutant reductions resulting from the settlement), include communities affected by environmental justice concerns. The work in the Anacostia is still scheduled for completion no later than 2025, and three of the four projects in that watershed are to be completed by 2018. 

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Green Infrastructure

As noted above, Defendants are attempting to incorporate GI into the CSO measures being undertaken in the Potomac and Rock Creek watersheds that would potentially reduce or eliminate the need for a storage tunnel in the Rock Creek Watershed, and reduce the size of the storage tunnel in the Potomac River Watershed).

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Pollutant Reductions

  • 3 million pounds of total suspended solids
  • 980,000 pounds biological oxygen demand
  • 4 million pounds of total nitrogen
  • 20,000 pounds total phosphorus   

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Health and Environmental Effects

  • Total Suspended Solids (TSS) – TSS indicates the measure of suspended solids in wastewater, effluent or water bodies. High levels of TSS in a water body can diminish the amount of light that penetrates the water column and reduce photosynthesis and the production of oxygen. 
  • Biological Oxygen Demand (BOD) – BOD is an indirect measure of the biologically degradable material present in organic wastes. High BOD means there is an abundance of biologically degradable material that will consume oxygen from the water during the degradation process. It may take away oxygen that is needed for aquatic organisms to survive. 
  • Nutrients - Excess levels of nitrogen and phosphorus in waters can produce harmful algal blooms. These blooms contribute to the creation of hypoxia or “dead zones” in water bodies where dissolved oxygen levels are so low that most aquatic life cannot survive.

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Civil Penalty

Defendant DC Water paid, pursuant to an October 10, 2003 settlement with the other parties, civil penalties totaling $250,000. DC Water also agreed under that settlement to:  (1) undertake SEPs valued at $1,700,000 (requiring the construction, operation and maintenance of rain gardens and other low impact development or low impact development retrofit projects); and (2) to pay to the Chesapeake Bay Foundation a total of $300,000 for design, installation, and maintenance of green roof demonstration projects within the CSS’s area service area located in the Anacostia River watershed.  

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State Partner

None, although the District of Columbia is named as a Defendant in this case.

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Comment Period

TThe proposed settlement, lodged in the U.S. District Court for the District of the District is subject to a 30-day public comment period and final court approval. Information on submitting comments is available at the Department of Justice website.

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For More Information, Contact:

Sushila Nanda
OECA/OCE - Water Enforcement Division (Mail Code 2243A)
1200 Pennsylvania Avenue, N.W.
Washington, D.C. 20460
(202) 564-4088

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