Gov. Bobby Jindal issued a state of emergency Wednesday, a first step in applying for possible future aid should the state experience flood damage once water levels rise in the Mississippi, Red and Atchafalaya rivers.

Heavy rains draining into the Mississippi, Ohio and Arkansas rivers are creating unusual January flood levels, and that water is expected to travel downriver to the Gulf of Mexico.

Forecasts call for the Mississippi River to rise to 44 feet in Baton Rouge by Jan. 19, close to the levels seen in the 2011 floods when water reached 44.8 feet. In New Orleans, the river is expected to rise to 17 feet.

The U.S. Army Corps of Engineers is evaluating forecasts and doing other preparation work to decide whether the Bonnet Carré Spillway will be opened to maintain the water level in New Orleans at a maximum of approximately 17 feet. River levees in New Orleans protect against water levels up to 20 feet, according to the National Weather Service.

The spillway opening is triggered when the river is flowing at 1.25 million cubic feet per second. Although it’s not certain that the spillway will be opened, a decision likely will need to be made by Jan. 9, said Mike Stack, chief of emergency management at the Corps’ New Orleans District.

A decision on whether to open the Morganza Spillway north of Baton Rouge will come after the Corps decides what to do with the Bonnet Carré, he said.

The Corps on Wednesday announced that the Old River Overbank Structure north of Angola has been opened because the Mississippi River is expected to reach 52 feet at the Knox Landing gauge.

The overbank structure is opened before water levels reach the trigger of 52 feet, which is expected to happen Friday . It’s the 15th time the structure has been opened, with the last time being in March.

In addition to the state declaration of emergency, a number of parishes have already issued their own declarations, including West Feliciana, East Carroll and Concordia.

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