Sewer Surprise at CJCA Meeting

At the January CJCA meeting, what was meant to be a discussion on the sewer bypass work happening where the C&O Canal intersects with Cabin John Creek at the bottom of the path from the one-lane bridge morphed into a productive and interesting conversation on a number of topics related to the canal, the sewer system, and related topics.  

A number of representatives from DC Water and from the National Park Service joined virtually—we are grateful for their time and the information they shared. The meeting also spawned follow-on activities, including sending invitations to both the WSSC and the NPS to attend an upcoming meeting.

The work being conducted now at the Cabin John Creek underpass and wooden footbridge over the canal is WSSC work (there was some confusion regarding which utility was responsible for this current work, as the WSSC sent the CJCA to DC Water).  According to DC Water, WSSC is replacing metering-related equipment. This is where the Potomac Interceptor, the main sewer, and the sewer pipe coming down Cabin John Creek merge. We will get more information on this project and pass that along to the CJCA.  

Perhaps the most interesting new information shared was regarding the sewer rehab project recently initiated in Cabin John and beyond. The Potomac Interceptor, which travels through Cabin John along the canal, is constructed of reinforced concrete pipe (RCP), ranging from 72 to 96 inches in diameter and terminates at the Blue Plains treatment plant. Known as the LZ09 and LZ03 Potomac Interceptor Pipe Rehabilitation, Montgomery County, MD and the District of Columbia Project, DC Water is being proactive and evaluating the state of these sewer lines and will develop a remediation strategy for the sewer pipe as necessary. Only after the state of the sewer pipes is known can a remediation plan be created, but DC Water notes that this project will extend the useful life of the RCP approximately 50 years.

This map illustrates the two zones that are part of this project (a third zone is along the DC/MD border). The project team includes DC Water and Sewer Authority (DC Water), NPS, and two design consultants, Greeley and Hansen and O’Brien & Gere. The project is following the National Environmental Policy Act (NEPA), and unfortunately the public comment period closed in June 2022. Lastly, the work on the LZ09 has an anticipated construction start date of spring 2024 and a completion date of fall 2025. For the LZ03 B zone, we only know the anticipated construction start date is 2025.

Lastly, the NPS shared information on what is known as the Timber Wall. This is just outbound from mile 11 (and outside Cabin John but of interest to many CJers). Built many years ago, these timbers were stacked to create a wall to support the towpath and the canal itself. Naturally, over time, the timbers have decayed, threatening the integrity of the Timber Wall. The NPS is actively considering steps to address this issue but did not share many of these at the meeting. The CJCA will invite the NPS to an upcoming meeting to discuss this particular project and the canal in general. Stay tuned.  

The well-attended meeting was aided by a number of CJCAers who shared their knowledge on the topics discussed. All shared their opinions—this is, of course, the CJCA!  

By Scott Lewis

CJCA Co-President, Contributing Writer

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