MORGANZA — The U.S. Army Corps of Engineers closed the last of the Morganza Spillway’s open gates Thursday afternoon.

The spring marked only the second time the structure had been opened since its completion in 1954.

The spillway, designed to divert high water from the Mississippi River into the Atchafalaya Basin, was previously opened in 1973.

The corps opened 17 spillway gates starting in May to alleviate flooding risks posed by the river, corps spokesman Ken Holder said in a news release.

The corps began closing gates on May 24 as the threat dissipated, he said.

Some of the gates were left open, allowing crews to inspect the structure and prepare a damage assessment, he said.

At the height of the flooding threat, 182,000 cubic feet of water per second was diverted through the structure, Holder said.