Temporary road closure on MacArthur Boulevard during Cabin John Bridge maintenance

U.S. Army Corps of Engineers, Baltimore District
Published Oct. 31, 2023
Updated: Oct. 24, 2023

Cabin John Bridge (Union Arch Bridge), located at the 7400 block of MacArthur Boulevard in Montgomery County, is scheduled to close Nov. 4-5 for necessary maintenance work performed by the Washington Aqueduct, a division of the U.S. Army Corps of Engineers, Baltimore District. A street closure and detour will be in place both days from 6:30 a.m. to 3 p.m.

A detour will be marked northbound on Wilson Lane, eastbound on River Road, northbound on Seven Lock Road, and westbound on River Road, with arrows directing traffic through a proposed detour route.

Washington Aqueduct staff walk along the Cabin John Bridge while conducting annual maintenance. (U.S. Army photo by Cynthia Mitchell)

Traffic controls will be in place to warn drivers approaching the area. Motorists should follow marked detours and are advised to stay alert while traveling through this location.

The Cabin John Bridge was built under the supervision of Gen. Montgomery C. Meigs of the U.S. Army Corps of Engineers between 1857 and 1863 to convey the Aqueduct’s conduit over the Cabin John Creek. Upon its completion, it was recognized as the longest masonry arch in the world, a record it held until 1903. It is listed in the National Register of Historic Places and designated as a National Historic Civil Engineering Landmark.

The bridge has a span of 220 ft. and a rise of 57.25 ft., with five spandrel arches at the west end and four spandrel arches at the east end, all of which are hidden by vertical side walls. (U.S. Army photo by Cynthia Mitchell)

The Washington Aqueduct produces drinking water for approximately one million citizens living, working, or visiting in the District of Columbia, Arlington County, Virginia, and other areas in northern Virginia, including portions of Fairfax County. The Aqueduct is a federally owned and operated public water supply agency that yields an average of 135 million gallons of water per day at two treatment plants in the District of Columbia.

For more information on the Washington Aqueduct, go to http://www.nab.usace.army.mil/Missions/Washington-Aqueduct.

Baltimore District delivers vital engineering solutions in collaboration with its partners to serve and strengthen the Nation, energize the economy, and reduce disaster risks. Headquartered near Baltimore’s Inner Harbor, Baltimore District provides design, engineering, construction, environmental and real estate expertise to a variety of important projects and customers. This support spans across five states, the District of Columbia, overseas, and across the Susquehanna, Potomac, and Chesapeake Bay watersheds. These civil and military missions and diverse engineering services support communities and warfighters while addressing the ever-growing list of emerging national security requirements and ultimately protecting the Nation.


Ken Barrett
Trina Littlejohn

Release no. 23-010