DC Water and U.S. EPA Agree on Operating Permit Limits for Protection of Chesapeake Bay

September 10, 2010

To improve the health of the Potomac River and Chesapeake Bay, the Blue Plains Advanced Wastewater Treatment Plant is further reducing the levels of nitrogen that it discharges into the Potomac. The plant already operates under one of the most stringent National Pollutant Discharge Elimination System (NPDES) permits in the country. The District of Columbia Water and Sewer Authority (DC Water) and the United States Environmental Protection Agency (U.S. EPA) have agreed to a new operating permit to lower these limits even further.

“DC Water was the first to meet the Chesapeake Bay Program goals to reduce nitrogen levels by 40 percent of the 1985 levels,” said DC Water General Manager George S. Hawkins. “And we have continued to meet those program goals every year since. Through the collaborative effort of the surrounding jurisdictions, we are making a difference in the health of our waterways.”

Nutrient removal is important to aquatic life because nutrients can cause algae growth that depletes oxygen in the marine environment. Under its existing permit, Blue Plains was operating well under its limit of 8.5 million pounds of nitrogen per year.

The new limit is 4.7 million pounds, which will require cutting-edge technology. “We began planning more than 10 years ago to achieve these new nitrogen removal goals,” Hawkins added. “In fact, we will be breaking ground in a few months for a new, $950-million enhanced nitrogen removal facility.”

The new operating permit sets new limits for nitrogen, bacteria and trash controls in combined sewer overflows. DC Water is already achieving the phosphorus removal requirements at Blue Plains.

The agreement came last week, just days before the Washington Post heralded the improved health of the Potomac River, calling it “cleaner now than it has been in decades, thanks largely to upgrades at Washington’s sewage plant.”

Latest News

Section of Potomac River in Cabin John, MD showing river and trees

Testing will continue through September 10 at six Maryland locations closest to January sewer collapse

DC Water is moving from daily Potomac River water quality testing to testing twice a week. The change is part of our continued response to the January Potomac Interceptor sewer collapse. Daily testing continued past the original July 31 end date and today will be the last day DC Water will test at the 10 current locations.

Map: Temporary southbound lane closure on Rock Creek and Potomac Parkway NW.

Starting on or about Aug. 7, 2026, weather permitting, drivers can expect a temporary lane closure southbound on Rock Creek and Potomac Parkway NW near the intersection of Virginia Avenue NW and F ...

Photo of inside Potomac Interceptor at Dulles showing newly lined tunnel

First of four emergency repairs on Potomac Interceptor finished

DC Water has finished the first of four emergency repair projects on the Potomac Interceptor sewer line. Crews completed work today to strengthen a 600-foot section of pipe at Dulles International Airport.

Upcoming Meeting

Board of Directors Meeting

April 24, 2023

Monday 9:00 AM

Latest Blog Post
Plastic bottles, cups and other floating debris on the surface of the Anacostia River before the Anacostia River Tunnel began operating.
Cleaner Waterways Start With Everyday Choices
Protecting our waterways starts with everyday actions and continues through critical infrastructure designed to keep pollution out of our rivers.
Upcoming Meeting

Upcoming Events

Customer Service Center Announcement

Payment Plan Incentive: provides a credit back of 50% of the last 3 payments made. Eligible participants are residential customers who have had an outstanding balance for 60 days or greater and with an outstanding balance of $500 or more.