The Corps’ Mississippi Valley New Orleans (MVN) did not open any bays on the Bonnet Carré Spillway today (Monday, May 20, 2019).

Today ties the record for consecutive days above flood stage for Baton Rouge with the number of days above flood stage with the Great Flood of 1927 at 135 days.  The record will indeed be broken going forward with high river stages forecasted well into June (2019).  A slide prepared by the National Weather Service titled, “Consecutive Days Above Flood Stage”, is attached, the report details record floods for port cities from Cairo, Illinois to Baton Rouge, Louisiana.

 The MVN operated the Bonnet Carré Spillway from February 27 to April 11, 2019, prior to 2019 the Spillway had never been operated in back-to-back years (2018 and 2019).  The required opening of the flood control structure twice in the same year represents another historic first. 

It is important to note that the record comparison for New Orleans (Carrollton Gauge) with the 1927 Flood is forever altered based on the flow diverted through the Bonnet Carré Spillway during flood events.  The Spillway was created to alleviate the threat of flooding upon the City of New Orleans after the historic flood of 1927 (Project Flood).

The maximum flow above the Spillway today was 1.329 million cfs based on the flow measured at Red River Landing (Mile 302.4 Above Head of Passes), with calculations and timing adjusted for downriver at Bonnet Carré.

BONNET CARRÉ SPILLWAY SECOND OPERATION 2019

The stages below the Spillway will be artificially controlled by the flow diverted form the Mississippi River through the open flood control structure and into Lake Pontchartrain.

The MVN manages the opening and closing of bays to ensure the maximum flow at New Orleans remains at/or below the trigger point flow of 1.25 million cubic feet per second (cfs).  The MVN will continue to oversee the operation of the Spillway as a flood control structure in accordance with the approved Bonnet Carré  Spillway Water Control Manual.  The MVN predicts the crest above the Spillway will occur between May 22 and May 29 (2019) and expects the operation of the flood control structure to continue until the second week of June.

Consecutive Flood Days Table[5].pptx