US Army Corps of Engineers
New Orleans District Website

Bonnet Carré Spillway Test

Published April 4, 2011

What: The U.S. Army Corps of Engineers, New Orleans District is scheduled to practice removing and replacing 10-20 wooden needles at bay 305 of the 350 bays.

The Corps performs the test on the structure when water is passing through the needles to simulate conditions in place during an actual opening.

It takes about one hour to lift and replace the 10-20 needles. The test is done during high water season as an opportunity to practice spillway operational procedures, especially for new crew members. As designed, the operation of the Bonnet Carré Spillway is very labor intensive and safe needle lifting and replacement as well as familiarization with the procedure is a priority.

When: Tuesday, April 5, 2011 at 10 a.m.

Where: Bonnet Carré Spillway - 16302 River Road, Norco, LA 70079

Planning to attend? Please call the Public Affairs Office at 504-862-2587. Media will not be allowed on the structure but there are viewing areas.

Directions to the spillway: The Bonnet Carré Spillway is located about 28 miles above New Orleans. To get there, take I-10 and exit at the I-310 interchange, proceeding south toward the river and the Luling-Destrehan Bridge. Before reaching the river, exit I-310 at the Norco-Destrehan exit. Take the Norco exit, which brings you to River Road. Turn right, toward Norco, and stay on River Road for about 6 miles. Just past Norco's Shell Refinery, the road rises onto the Bonnet Carré Spillway levee; nearby is the Corps' Bonnet Carré office.

Current High Water Background: The Corps activated phase I flood fight procedures March 14 to assist local levee authorities and districts with increased levee inspections and surveillance operations along the Mississippi River. The Mississippi River is currently cresting at 14 feet at the Carrollton Gauge in New Orleans, as forecasted by the National Weather Service (NWS).

Based on current forecast, the Corps does not plan to open the Bonnet Carré Spillway structure. Operation of the spillway is determined by water flow and velocity. The spillway structure is operated when the high river flows exceed 1.25 million cubic feet per second (cfs). When open, the spillway is able to divert up to 250,000 cfs from the river into Lake Pontchartrain, thus relieving pressure on local levees, lowering river stages, and reducing the velocity of the river current south of the spillway.

The decision to open the Bonnet Carré Spillway structure is made by Mississippi River Commission President Maj. Gen. Michael Walsh, commander of the Corps' Mississippi Valley Division in Vicksburg, Miss. The spillway was last opened during the 2008 high water season.


Release no. 11-091