Repairs to the broken Potomac Interceptor pipeline are expected to wrap up by mid-March, D.C. Water said, clearing the way for cleanup of the Potomac River and C&O Canal.
Repairs to the broken Potomac Interceptor pipeline are expected to wrap up by mid-March, D.C. Water said, clearing the way for cleanup of the Potomac River and C&O Canal.
Officials said the long-term restoration will address every area touched by the wastewater.
“The restoration plan will focus on the immediate collapse site area, the creek beds, the surface areas where that wastewater impacted the shoreline along the Potomac River in this immediate area, and as well as, of course, the C&O Canal,” said Sherri Lewis with D.C. Water.
Cleanup work can only begin after the bypass pumping system is shut down. Lewis said some steps may occur beforehand, but full restoration cannot begin until a formal plan is approved.
While there is an opportunity to mitigate some issues now, Lewis said, “this is not the start of the full environmental restoration.”
The restoration plan is being developed with the Environmental Protection Agency, which will serve as the lead federal agency for cleanup, along with the U.S. Army Corps of Engineers, the Maryland Department of the Environment and the D.C. Department of Energy and Environment.
To help prepare for the cleanup, the Army Corps’ Baltimore District is evaluating engineering solutions to limit further contamination and ease the transition into restoration
Col. Francis Pera said one option under review is a series of check dams that could capture water before it enters the Potomac River and allow it to be pumped back into the Interceptor.
“We hope to have a solution here pretty soon,” he said.
Pera and Corps teams have already installed a pumping system to keep stormwater from nearby roads from entering the repair site.
The combined cost of repairs and cleanup is now estimated at about $20 million.
Negotiations over how to cover the costs continue under D.C. Mayor Muriel Bowser’s federal emergency declaration. In the emergency declaration, the federal government has agreed to pay 75% of the bill for the repair and restoration, but Mayor Muriel Bowser had asked federal agencies to cover 100%.
Concern about warming weather
As repairs continue, some experts are worried about what warmer temperatures in the coming weeks and months could bring.
Dr. Cherie Schultz, the director of Cooperative Water Supply Operations at the Interstate Commission on the Potomac River Basin, spoke during a regional virtual meeting coordinated by the Washington Metropolitan Council of Governments on Monday.
While she is confident drinking water has not and should not be affected by the spill, she has other concerns.
“In future months, maybe this summer, maybe for a number of years … the nutrients, nitrogen and phosphorus from the sewage may increase the growth of algae downstream and may increase the likelihood this summer of harmful algal blooms,” Schultz said.
Excessive algae consumes dissolved oxygen in the water, depriving fish and other animals of what they need. It also blocks sunlight needed for aquatic plants.
“Solid sewage material on the river bed may increase biological oxygen demand this summer in the sediments and (increase) the likelihood of fish kills,” Schultz said.
She has been monitoring bacteria readings since the Jan. 19 pipeline failure. While some levels have been elevated, Schultz said they are expected to fall in the coming weeks.
“We expect them to fall to near background levels due to die off of bacteria and flushing by river-flow,” she said.
When will the river be safe again?
There is no set date for lifting the recreational water advisory. D.C. Health and the Department of Energy and Environment will decide based on the results from water quality testing.
Lewis noted river conditions can change quickly after storms and snowmelt, and agencies will rely on sampling to determine when it is safe for the public to return.
“They will be evaluating that as we continue through this process,” she said.
A firm timeline for full restoration will not be determined until repairs are complete and the final restoration plan is approved.
D.C. Water said it will hold public meetings this week:
- Wednesday at 7 p.m. at D.C. Water Headquarters in Navy Yard in the District, and
- Thursday at 7 p.m. at Walt Whitman High School in Bethesda, Maryland
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