Corps Begins Closing Bonnet Carré Spillway

With the Mississippi River at the Carrollton Gage in New Orleans, La., beginning a slow fall, the New Orleans Engineer District began closing bays at the Bonnet Carré Spillway March 15, close to a month after the structure was opened for the 13th time in its 88-year history.

The Corps began opening the spillway February 27. At the river’s peak flow, the Corps had opened 206 of the spillway’s 350 bays for a total discharge of 213,000 cubic feet per second (cfs.). The Bonnet Carré Spillway is activated when the flow rate at the structure reaching 1.25 cfs., which amounts to about 17 feet at the Carrollton Gage. By March 27, there were 152 open bays, for a discharge of 135,000 cfs.

The National Weather Service forecasts the Mississippi River in New Orleans will finally drop below 16 feet the first week of April. By April 22, the Weather Service estimates the river will be below 14 feet and continuing to drop.

The 2019 opening of the Bonnet Carré represents the first time in the structure’s history that it’s been opened in consecutive years. This also marks the first time it has been used three out of four consecutive years. For much of its history, the spillway was opened on average once a decade. Exceptions include the 1970s, when it was opened three times, and since 2008, when it has been activated five times.