Major Potomac River and Chesapeake Bay Pollution: Water Filtration Plant for Montgomery and Prince George's Counties Faces Possible Lawsuit for Clean Water Act Violations

More than 28 million pounds of sediments and aluminum dumped in less than four years: Potomac Riverkeeper and Chesapeake Bay Foundation announce Notice of Intent to Sue Washington Suburban Sanitary Commission for illegal discharges

(WASHINGTON, D.C.)—The Washington Suburban Sanitary Commission (WSSC), owner of the Potomac Water Filtration Plant, is facing a new legal challenge today for polluting the Potomac River and the Chesapeake Bay in violation of the Clean Water Act. Attorneys from Environmental Integrity Project (EIP), on behalf of the Potomac Riverkeeper, together with the Chesapeake Bay Foundation (CBF), announced the groups' intent to file a lawsuit against WSSC for years of unchecked water pollution from the filtration plant.

The Potomac Water Filtration Plant is located near Seneca, Maryland and discharges approximately eight million gallons of wastewater per day into the Potomac River, alongside the historic C & O Canal National Historical Park and upstream from Great Falls National Park. The facility provides drinking water to the majority of Maryland residents in Montgomery County and parts of Prince George's County, and has been operating under a five-year permit that expired 11 years ago. Potomac Riverkeeper and CBF allege that the WSSC facility has and continues to discharge millions of pounds of sediments (formally known as total suspended solids or TSS) and aluminum directly into the river instead of treating these wastes and disposing of the remaining wastestream off-site.

All indications are that the solids treatment unit, which became operational in 2002, simply doesn't work. The result is massive amounts of untreated pollution flowing daily into two of the nation's and region's most cherished waterways: the Potomac River and, ultimately, the Chesapeake Bay. More than a decade after the permit expired in 2002 and the solids treatment unit went online, WSSC and the Maryland Department of the Environment (MDE) still have not arrived at a fix. Both local water bodies continue to suffer as a result of the stalemate between the two governmental entities over the permit and the treatment unit overhaul.

"Plant records indicate that over the past four years, the Potomac River Filtration plant has discharged enough sediment and aluminum into the river below Seneca to fill more than 1,400 ten ton dump trucks," said EIP Executive Director Eric Schaeffer. "The Baltimore filtration plant is much cleaner, and the Army Corps facility off MacArthur Road has expanded its sediment basins to keep pollutants out of the river. Like its counterparts, we think WSSC should be able to deliver drinking water to Montgomery and Prince Georges County residents without clouding the Potomac with mud and metals that can harm aquatic life, or making it less enjoyable to fish, swim, or boat in its waters."

"The discharges from the WSSC facility are unacceptable because of both the scale of the pollution as well as the duration. This has been going on for years, just above other drinking water intakes for DC area residents. Other water treatment plants in the region operate under permits that are much more protective of the river," said Matthew Logan, President of Potomac Riverkeeper. "This notice is being given to let WSSC, MDE, and the public know that this pollution has to stop now."

"The sediment being discharged, in violation of permit limits, is damaging the health of the Potomac River and Chesapeake Bay, and toxicity testing, which is required by the permit, is needed to determine what damage is being done by the aluminum," said Christine Tramontana, CBF Litigation Counsel. "The goal of this action is to push WSSC to upgrade its facility, stop unpermitted discharges, and ensure accurate monitoring. MDE and WSSC must ensure that permit limits, crucial to Chesapeake Bay Blueprint efforts, are met."

As a result of tens of thousands of pounds of chemicals added every week to aid the ailing treatment process, WSSC discharged nearly 27 million more pounds of TSS than it took in and added nearly 1.4 million pounds of aluminum—in less than four years. In addition, WSSC discharges significant amounts of phosphorus into the Potomac River without any permit limits and zero treatment. Making matters worse, WSSC is several orders of magnitude less efficient at removing and treating solids and other pollutants than its fellow local water suppliers.

In 2010, pollution limits were established for Chesapeake Bay, known as a Total Maximum Daily Load (TMDL), which is designed to reduce the amount of pollution—specifically sediment, nitrogen and phosphorus, released into the Bay and its tributaries, including the Potomac River, and over time restore the water quality of the watershed.

Excess sediments in the river and Bay degrade the aquatic biota, especially benthic communities and submerged vegetation. Aluminum is a metal that is known to stress fish and amphibian populations yet MDE has allowed WSSC to discharge aluminum in amounts well above EPA's National Recommended Water Quality Criteria for more than a decade. Requiring the Potomac Water Filtration Plant to get on board with the mandates of the Clean Water Act (CWA)—including the Chesapeake Bay TMDL—and devise a way to produce drinking water without worsening the health of the Potomac River and Chesapeake Bay, is essential.

Prior to filing a CWA case, plaintiffs are required to first submit to WSSC, as well as state and federal regulators, a 60-day notice of intent to sue. Potomac Riverkeeper, CBF, and EIP are hopeful that WSSC will work with them to reach a resolution that makes sense for WSSC, its customers, and the resource upon which WSSC relies, the Potomac River and the Chesapeake Bay.

But if action hasn't been taken to resolve the violations within the 60-day time period, the plaintiffs intend to file a complaint in federal court. The lawsuit will seek penalties for illegal discharges and other violations of WSSC's permit and will require WSSC to identify and address the operational problems with the solids treatment unit. In addition, the plaintiffs hope this litigation will encourage MDE to issue WSSC, sooner than later, a new NPDES permit with more protective limits and operating conditions.

To see the full text of the NOI filing, go to:


The Environmental Integrity Project ( is a nonpartisan, nonprofit organization established in March of 2002 by former EPA enforcement attorneys to advocate for effective enforcement of environmental laws. EIP has three goals: 1) to provide objective analyses of how the failure to enforce or implement environmental laws increases pollution and affects public health; 2) to hold federal and state agencies, as well as individual corporations, accountable for failing to enforce or comply with environmental laws; and 3) to help local communities obtain the protection of environmental laws.

Potomac Riverkeeper is a membership organization established in 2000 dedicated to protecting water quality throughout the Potomac River watershed. Potomac Riverkeeper utilizes a variety of approaches, including legal action, to ensure the Potomac is again drinkable, fishable, and swimmable. Potomac Riverkeeper uses the Clean Water Act and other federal, state and local environmental laws to curb pollution that damages water quality in the Potomac. It has trained over 300 local citizens to serve as volunteer Riverwatchers throughout the watershed, and is a member of the Waterkeeper Alliance. 

With its founding in 1967, the Chesapeake Bay Foundation (CBF) became the only regional conservation organization committed solely to Saving the Bay. CBF is working toward a restored Bay through legislative advocacy at the national, regional, and state levels; habitat restoration on land and in the water; strategic public communications and engagement throughout the watershed; and comprehensive environmental education for students, teachers, and principals of the region. CBF's vision is a restored Bay with healthy rivers and clean water; sustainable populations of crabs, fish, and oysters; thriving water-based and agricultural economies; and a legacy of success for our children and grandchildren.

MEDIA CONTACTS: Patrick Mitchell for Environmental Integrity Project at (703) 276-3266; Matthew Logan for Potomac Riverkeeper at (301)-512-7027; John Surrick for CBF at (443) 482-2045.

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