Friends of Historic Great Falls Tavern

Update on construction at the C&O Canal

Friday, 13 April 2018

Since December 2017, work has continued to progress at the $6.7 million “Repair to Various Watered Structures between Locks 5 -22” project, in Montgomery County, MD. The purpose of the project is to improve several locks, waste weirs, bridges and other water control structures within one of the most popular segments of the C&O Canal. These improvements will help the park’s historic structures withstand impacts from Potomac River floods and make the features easier to maintain. This project consists of work around the following areas of the C&O Canal: Swains Lock, Great Falls Tavern, Olmsted Island, Carderock, Rock Run Culvert, and Lock #7. This email provides an update of the activities currently underway that are associated with the project.

This week the construction located a few hundred feet upstream of Lock #21 (Swain’s  Lock), near milepost 16.9, which consisted of strengthening a section of the towpath that overtops during floods via the installation of an articulated concrete mat “fuse plug spillway” has been completed. The local detour has been removed and the towpath has been opened to normal pedestrian and vehicular traffic.

Currently work is ongoing near the Great Falls Tavern to repair the waste weir water control structure adjacent to Lock #20 (approximate milepost 14.4). Pedestrians and vehicles should continue to use the detours that have been in place since January 2018 and are expected to be in place until the end of this calendar year.

The National Park Service anticipates the start of the detour around the work area at the Rock Run site (approximate milepost 8.9) to begin on or about Wednesday, April 18, 2018. Work at Rock Run consists of the stabilization, preservation, and rehabilitation of a historic stone wall that supports the towpath and runs on either side of a historic culvert which carries Rock Run (local stream) underneath the canal. Similar to other sites associated with this project, the work will require removal of several trees that have grown in and adjacent to the historic stone walls. Once the work is complete, the contractor will restore the site with native vegetation. While work is ongoing at the Rock Run work site, a local detour will direct visitors over a series of bridges at Lock 10 & 11, and a temporary bypass trail for a total distance of approximately 0.2 miles between mileposts 8.8 to 9.0. It is anticipated that work will continue at Rock Run until September 2018 (weather dependent). A photo of the existing condition at Rock Run and map showing the temporary detour route is attached.

Work for the entire project over each of the eight work areas is anticipated to continue until Spring 2019.

[From email note, Joseph Reed (C&O NHP), 13 April 2018, “CHOH 150819 …”]