After I published the winding tale of the Tiber Creek turned Washington City Canal turned “River of Slime”/Constitution Avenue, I got some very interesting comments and letters. Some corrected details of the story (i.e. I was reminded to clarify that Adolph Cluss was more than “a young German immigrant engineer”). I was also given some very fascinating additional information. Specifically, I learned that the original outlet to Boss Shepard/Cluss’s sewer was uncovered in an archaeological dig JUST LAST MONTH…
When I taped my most recent WAMU radio segment with Rebecca Sheir a few weeks ago, we noticed a construction site just south of the Lockkeeper’s House. This, the 17th Street Levee Project, is an effort of national and local agencies to modernize the mall’s levee system that dates to the late 1930’s, and to hold off flooding from the Potomac.
Last month, as part of the project, workers uncovered the original outlet to Shepard & Cluss’s “tunnel of slime” – this is the sewer they had created to bury the Washington City Canal and form today’s Constitution Avenue.
To comply with the National Preservation Act, the agencies performed archaeology on the historic outlet, took the structure apart, and set aside the stones. The excavation did not reach the bottom of the structure, which had an interior diameter of 24 feet. The sewer was bone dry and in perfect condition. This is likely the same arch shown in the engraved illustration of the flushing gates that you can see in my original blog post:
Shepard’s sewer outlet was probably closed during the 1930’s when the city’s sewer system was modernized or when the modern mall was completed and the river line changed.