Cabin John Bridge - NEW Corman Construction

Department of Army Corps Of Engineers

Washington, D.C.

The Cabin John Bridge (Union Arch Bridge), completed in 1864, is designated as a Historic National Civil Engineering Landmark by the ASCE, and is listed in National Register of Historic Places
Until 1903, it was the longest, single span, masonry arch in the world
The Cabin John Bridge, by original design not a bridge at all, carries an 8’ diameter aqueduct over Cabin John Creek and Cabin John Parkway, as well as roadway
Still used today to convey drinking water from Great Falls, Maryland, over Cabin John Creek and Cabin John Parkway, to Washington, DC.
All work conducted under the intense scrutiny of local residents, the local historical society and the US Army Corps of Engineers
Contract involved replacement of the bridge deck and large-cut stone parapet elements
The aqueduct, the main water supply for Washington, DC, had to remain operational during construction
Bridge access was extremely limited due to the road’s 15-ton maximum weight capacity
Demolition work took place from 9pm – 5am to minimize hazards to motorists on roadway below bridge
Bridge work was elevated 100’ over Cabin John Parkway and included specialty items such as an in-house designed swing scaffolding system, cast-in-place concrete, stone masonry, and architectural ornamental detailing iron
The project required complete closure of a major artery between Bethesda, MD, and Georgetown, in Washington, D.C., dictating a tight rebuild schedule
Corman completed the project 5 days ahead of schedule in only 101 days