Contacts:
For Controlled Emergency Overflow Questions:
Lyn Riggins, WSSC Water
Lyn.Riggins@wsscwater.com
301-206-4002
For Pipe Collapse/Repair Questions:
Sherri Lewis, DC Water
Sherri.Lewis@dcwater.com
202-787-2209
Laurel, Md. – July 31, 2025 – Laurel, Md. – July 31, 2025 – With excessive rainfall forecasted for the region—potentially totaling 4 to 6 inches—WSSC Water and DC Water are actively monitoring weather conditions and implementing mitigation strategies to minimize the risk of a controlled emergency sewage overflow from the Anacostia Wastewater Pumping Station (WWPS) in Capitol Heights, Maryland.
The agencies are working together to protect communities and the environment following the July 20 collapse of the 108-inch diameter Anacostia Sewer Force Main in Northeast Washington, D.C. near Kenilworth Aquatic Gardens. While a controlled emergency overflow remains a last resort, preparations are in place to manage increased wastewater flows due to the anticipated storm.
WSSC Water’s Anacostia WWPS pumps approximately 60-65 million gallons of sewage per day (MGD) into the sewer line during dry weather. While DC Water’s containment efforts can manage up to 120 MGD of flow, excessive rainfall may exceed that capacity depending on a number of factors, including the duration and rate of rainfall.
To reduce the likelihood of an overflow, DC Water has installed:
- Retaining walls capable of containing up to 120 million gallons per day (MGD) of sewage during dry weather.
- Secondary containment systems, including sandbags and trenching, to divert excess flow safely to storm drains.
- 24/7 camera surveillance to monitor flow conditions in real time and respond immediately to any changes.
Additionally, WSSC Water has the capacity to store approximately 7 million gallons of wastewater at the WWPS, which will be fully utilized before any overflow is considered.
These proactive steps are designed to prevent sewage from backing up into streets and homes in Northeast D.C., which could occur if the system becomes overwhelmed. A controlled emergency sewage overflow—if necessary—would direct untreated sewage into Beaverdam Creek, which flows into the Anacostia River. This would only be done to protect public health and property in the District.
If an overflow becomes necessary, signs will be posted along affected waterways advising residents to avoid contact for up to 30 days. Updates will be provided with the start time, volume, and end time of any overflow event.
It is important to note that drinking water systems are not affected. Both WSSC Water and the District draw drinking water from the Potomac River, which is not connected to the impacted area.
WSSC Water and DC Water have notified the Maryland Department of the Environment, D.C. Department of Energy and Environment, Prince George’s County Health Department, and the U.S. Environmental Protection Agency. The agencies remain in close coordination as repairs to the sewer line continue.l Protection Agency.