This July 19, 2002, file photo, shows the Mackinac Bridge that spans the Straits of Mackinac from Mackinaw City, Mich. Oil transport company Enbridge says Wednesday, a gap has opened between a section of its Line 5 pipeline and the lake bottom in Michigan's Straits of Mackinac. Erosion has washed away sediments beneath the pipeline, opening a gap that exceeds the 75-foot limit set under a state easement. The company says it's awaiting government permits to install screw anchors for additional support in that spot and others along the underwater line. (AP Photo/Carlos Osorio, File)

The U.S. Army Corps of Engineers says it's preparing to decide whether to let Canadian oil transport company Enbridge install supports for its underwater oil pipeline in Michigan's Straits of Mackinac.

Enbridge disclosed Wednesday that had opened a gap beneath one of two Line 5 pipelines in the channel linking Lakes Huron and Michigan. The gap is about 6 (1.83 meters) wider than allowed under a state easement.

The company says the pipe's integrity isn't threatened. But it wants to install more than 50 screw anchors for greater stability.

Michigan has granted a permit. Enbridge says it's been waiting 16 months for the Army Corps to do likewise.

Spokeswoman Lynn Rose said Thursday the Corps recently received information it needed from Enbridge to make a decision, which will come soon.