Ambassador Bridge Rehab Begins

Modjeski and Masters performs an internal inspection and evaluation of one of the bridge’s main steel cables. (Photo courtesy of Modjeski and Masters)

Rehabilitation and new construction work has begun on the Ambassador Bridge, one of the most vital trade crossings in North America. More than 25% of all commerce between the U.S. and Canada crosses this 7,500-ft suspension bridge over the Detroit River, connecting Detroit, Mich., and Windsor, Ontario.

The project is headed by bridge engineering firm Modjeski and Masters as part of a design-build delivery model, and includes bridge rehabilitation, new construction, and inspection and evaluation of the main steel cables.

To ensure the bridge’s safe, continued use, the bridge’s owner needed to assess the effect of decades of heavy use, a task complicated by the fact no load rating had been done since its completion in 1929. (At the time of its completion, the Ambassador Bridge was the longest suspension bridge in the world and used 21,000 tons of steel.)

Modjeski and Masters completed the task in several phases, beginning with the load rating. This resulted in additional contracts for structural steel repairs, replacement of suspender ropes and the main span deck, and a main cable inspection.

Additional photos of cable inspections on the Ambassador Bridge can be found here.