The Army Corps of Engineers this afternoon began to close the Gulf Intracoastal Waterway barge gate at the Inner Harbor Navigation Canal-Lake Borgne Surge Barrier as Tropical Storm Karen makes its way toward the Gulf Coast.

The closure is a precautionary measure the corps takes when tropical weather threatens the metro area.

A smaller navigational gate on the Gulf Intracoastal Waterway and the Bayou Bienvenue life gate will remain open for now, the corps said.

The barrier is a concrete wall that stretches 1.8 miles across the Mississippi River Gulf Outlet and the Golden Triangle Marsh.

The barrier is designed to reduce the risks of storm surge for some areas Hurricane Katrina hit hardest, including New Orleans East, Gentilly, the 9th Ward and St. Bernard Parish.