"Downriver in Louisiana, the Army Corps of Engineers began opening the first floodgates at the Bonnet Carre spillway about 30 miles northwest of New Orleans. Workers pulled restraining devices off 28 of the spillway's 350 gates, and the corps said it will monitor river levels before deciding to open more.
It's the 10th time the spillway has opened since the structure was completed in 1931.
The corps also has asked for permission to open the key Morganza spillway north of Baton Rouge. Officials warned residents that even if it were opened, residents could expect water 5 to 25 feet deep over parts of seven parishes. Some of Louisiana's most valuable farmland is expected to be inundated.
Later on Monday, state officials planned to begin moving some prisoners from the Angola state penitentiary, north of Baton Rouge.
Peak flows are not expected to reach the New Orleans area for more than two weeks.
Engineers say it is unlikely any major metropolitan areas will be inundated as the water pushes downstream over the next week or two. Nonetheless, officials are cautious.
# Bonnet Carre Spillway. In Louisiana, the Corps on Monday opened some of the spillway's gates, diverting some of the Mississippi into Lake Pontchartrain to ease pressure on New Orleans' levees. Built about 30 miles upriver from New Orleans in response to the 1927 flood, it was last opened in 2008. Monday marked the 10th time it has been opened. From the lake, the water flows east into the fertile fishing and oyster grounds of Lake Borgne and the Mississippi Sound, and ultimately the Gulf of Mexico.
# Morganza Spillway. The Corps has asked for permission to open some of the gates on this spillway, located 35 miles north of Baton Rouge, for the first time since 1973. Officials warned residents that even if it is opened, they can expect water 5 to 25 feet deep over parts of seven parishes. Some of Louisiana's most valuable farmland is expected to be inundated and towns like Houma and Morgan City would have to be evacuated. Already, communities are sandbagging as a precaution.
# West Atchafalaya Floodway. This last line of defense for New Orleans was built to take half of the Mississippi's highest flows and divert that to the Gulf. So far the Corps has not said it is considering opening this system."
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