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 for sewer repairs 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.

The emergency repairs are being done as a proactive measure as there is no active sewage spill or overflow. Inspections on the pipe – part of the 54-mile Potomac Interceptor sewer pipeline - did find corrosion and worn concrete inside this pipe section. Fixing it now will help protect the Potomac River, nearby communities, and the drinking water supply.

Weather permitting, we will begin strengthening the most critical part of the pipe the week of July 20, with a concrete-like material called geopolymer. The material coats the inside of the pipe and helps make it stronger. This section of the pipe is also surrounded by concrete, which gives an added layer of protection.

After that, we will get ready for the slip lining. That’s when new pipe sections are inserted inside the old pipe. This creates a stronger pipe inside the existing one.

To reach the sewer line, our crews will dig two work areas. One will be near the Pennyfield Conservation Area boat ramp. The other will be about halfway between the boat ramp and the National Park Service parking lot at Pennyfield Lock 22. Digging is expected to last about two weeks.

The new pipe sections are expected to be installed starting in August. While part of the pipe is open, we do not expect odors to be a major issue because wastewater will not be flowing through that section.

Work began last month to prepare the site for the emergency work. The bypass will operate for the duration of the repair, moving wastewater through the temporary pipeline - more than 1,700 feet long - and back into the sewer line downstream.

We expect to finish the project at the end of September. When the work is done, this part of the sewer line will be “like new” condition. The new pipe is designed to last 50 to 75 years before it shows signs of wear.

During construction, we are working with WSSC Water to help protect the drinking water supply. WSSC Water’s drinking water intake is downstream of the repair area. An emergency plan is already in place if a problem occurs.

We know this area is important to people who live nearby, visit the C&O Canal, and use the Potomac River. We are working with the National Park Service, Montgomery County, WSSC Water, local summer camps, paddlers, and community members to keep people informed, answer questions and keep access to the river open where we can.

The emergency repair work near Pennyfield Lock is part of DC Water’s 10-year, $625 million Potomac Interceptor Rehabilitation Project, and is part of the agency’s revamped inspection and repair prioritization efforts. For more information, visit dcwater.com/potomacinterceptor.