Corps Opens Gates at Louisiana’s Bonnet Carre Spillway

May 10, 2011 by

The Army Corps of Engineers on May 9 partially opened a spillway that diverts the swollen Mississippi River’s rising water into a lake to ease pressure on the levee system in greater New Orleans.

Several hundred curiosity-seekers watched from the riverbank as workers used cranes to remove some of the Bonnet Carre Spillway’s wooden barriers, which serve as a dam against the high water.

The spillway, which the Corps built about 30 miles upriver from New Orleans in response to the great flood of 1927, last opened during the spring 2008. The action marked the 10th time it has been opened since the structure was completed in 1931.

“It’s a historic time we’re in right now,” said Col. Ed Fleming, commander of the Corps’ New Orleans district.

Rufus Harris Jr., 87, said his family moved to New Orleans in 1927 only months after the flood killed more than 500 people and displaced more than 700,000 others from their homes. He was too young to remember those days, but the stories he heard gave him a healthy respect for the power of the river.

“People have a right to be concerned in this area because there’s always a possibility of a levee having a defective spot,” Harris said as he watched water pour through the spillway’s bays.

The Corps planned to open 28 of the spillway’s 350 bays. Fleming said officials will monitor the river levels before deciding whether to open more bays.

The corps also has asked the Mississippi River Commission for permission to open the Morganza spillway north of Baton Rouge, which diverts river water into the AtchafalayaBasin. Completed by the Corps in 1954, it hasn’t been opened since 1973.

Plaquemines Parish President Billy Nungesser, who watched the spillway’s opening from an area reserved for officials, said high water isn’t likely to force evacuations in his parish.

“It’s nothing to panic about, but it’s obviously a concern we have,” he said.

State officials started moving some prisoners from the Angola state penitentiary in West Feliciana Parish, north of Baton Rouge, as backwaters rise.

Eight buses and several vans as well as police escorts moved inmates Monday with medical problems from the prison. A trailer carrying livestock left the facility which includes a farm in its operations.

Fewer than 200 people were evacuated though more could be taken out later. Inside the prison, some prisoners were being moved to less vulnerable buildings.

The prison has not been flooded since 1927, although prisoners have been evacuated at other times when high water threatened, most recently in 1997. The 18,000-acre prison holds more 5,000 inmates. Angola is bordered on three sides by the Mississippi River.

In 2003, construction was completed on improvements to add height to the levees protecting the prison. On May 9, the Mississippi was about 12 feet below the levee tops.

The Bonnet Carre diverts river water into Lake Pontchartrain and from there into the Gulf of Mexico. Opening all of its bays takes about 36 hours. The structure is designed to pass a maximum of 250,000 cubic feet of water per second. Morganza, which is composed of 125 gated openings, is designed to pass a maximum of 600,000 cubic feet of water per second and would take about 15 hours to completely open.

The Bonnet Carre spillway runs about 5.7 miles from the structure at the Mississippi River to Lake Pontchartrain. Officials project the Bonnet Carre spillway could be open for at least two weeks. It’s unclear when Morganza might be opened.

Pat Lafaye, 71, of Metairie, expressed confidence that the levees protecting greater New Orleans can hold back the high water.

“We went through Katrina and we did fine,” Lafaye said of her family’s home. “I’m too old to be worried.”

Mary Foster reported from the state penitentiary.