Line 5 at the Straits of Mackinac: Built to last

Construction of Enbridge’s Line 5 crossing at Michigan’s Straits of Mackinac, in 1953, was an extraordinary feat of engineering, and still exceeds today’s standards for pipeline engineering. Bechtel Corporation—one of the most respected firms in the world, with the Hoover Dam among its achievements—managed the engineering, procurement and construction of the pipeline. The underwater contractor for the Line 5 Straits crossing was Merritt-Chapman & Scott, which built the iconic suspension bridge over the Straits of Mackinac. Learn about our Great Lakes Tunnel Project.