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

Pennyfield Lock Potomac Interceptor bypass pipeline running next to C & O Canal with equipment

There is no active spill or overflow. Work to strengthen the pipe to begin soon.

Today, DC Water completed construction on a temporary bypass system as part of sewer repairs on the Potomac Interceptor near Pennyfield Lock in Potomac, Maryland. Crews turned on the pumps and successfully tested the system. With the bypass now ready, it will allow us to begin the emergency repairs inside the pipe by carrying the wastewater around the repair area.

DC Water Officials with NPS and ANC commissioners doing ceremonial groundbreaking

Today, DC Water broke ground on the Piney Branch Tunnel, the final major tunnel in our Clean Rivers Project. This work will help keep sewage and trash out of local waterways and make Rock Creek, the Potomac River, and the Chesapeake Bay cleaner for our community.

When we finish the Piney Branch Tunnel, it will hold at least 4.2 million gallons of rainwater and wastewater during heavy storms. Instead of overflowing into Piney Branch, that water will go to the Blue Plains Water Resource Recovery Facility, where it will be treated.

Photo of the drop shaft looking from above down into the bottom

Starting the week of July 13, 2026, people who live, work or travel near the Canal Road NW entrance to Georgetown University may hear controlled blasting. This work is part of our Potomac River Tunnel Project.

When blasting happens, neighbors may hear a brief noise or feel light shaking. Drivers, cyclists, and pedestrians on Canal Road NW may also be stopped for a few minutes while we safely complete each blast.

Upcoming Meeting

Board of Directors Meeting

April 24, 2023

Monday 9:00 AM

Announcement

DC Water Officials with NPS and ANC commissioners doing ceremonial groundbreaking
DC Water Breaks Ground on Piney Branch Tunnel, Final Phase of DC Clean Rivers Project

Today, DC Water broke ground on the Piney Branch Tunnel, the final major tunnel in our Clean Rivers Project. This work will help keep sewage and trash out of local waterways and make Rock Creek, the Potomac River, and the Chesapeake Bay cleaner for our community.

When we finish the Piney Branch Tunnel, it will hold at least 4.2 million gallons of rainwater and wastewater during heavy storms. Instead of overflowing into Piney Branch, that water will go to the Blue Plains Water Resource Recovery Facility, where it will be treated.

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Five photos from the American Water Works Association (AWWA) ACE26 conference featuring panel discussions, technical presentations, networking, and attendees posing at the ACE26 display.
ACE26 Highlights: How DC Water Advanced the Conversation on Water
More than 80 DC Water employees joined thousands of water professionals in Washington, D.C., sharing expertise, building partnerships and advancing conversations that will help shape the future of water.
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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.