ST. IGNACE (AP) — An anchor will be recovered from the bottom of the Straits of Mackinac after it became detached from a cable during maintenance of an oil pipeline, Enbridge Energy said Friday.

“There was no risk to the pipelines,” the company said in a written statement. “The anchor was placed in between the dual pipelines in an area more than 500 feet from either pipeline per a pre-approved anchoring plan.”

The incident involved a contractor. Enbridge’s Line 5 crosses the bottom of the straits, a roughly 4-mile-long waterway connecting Lake Huron and Lake Michigan. The state said it was told about the 15,000-pound anchor Wednesday. Enbridge wants to build a tunnel in the water to house the pipeline. It has a permit from the state but needs approval from the U.S. Army Corps of Engineers.

Critics contend the underwater section — two parallel pipes laid in 1953 — is vulnerable to a spill that could pollute hundreds of miles of waters and shorelines. Enbridge, backed by industry and labor groups, insists it is in good condition and has never leaked. Gov. Gretchen Whitmer, a Democrat, ordered the Line 5 pipes closed by mid-May, a deadline the company ignored. A lawsuit is pending in federal court.