The Corps’ Mississippi Valley New Orleans (MVN) opened 10 additional bays on the Bonnet Carré Spillway today (Saturday, May 11, 2019).

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 maximum flow above the Spillway today was 1.248 million cfs based on the flow measured at Red River Landing, with calculations and timing adjusted for downriver at Bonnet Carré.

BONNET CARRÉ  SPILLWAY OPERATIONS                                                                                                                                                                                                               SECOND OPENING 2019

DATE CARROLTON GAUGE (NEW ORLEANS) BAYS OPENED TOTAL NUMBER OF BAYS OPEN TOTAL NUMBER OF BAYS CLOSED SPILLWAY DISCHARGE                 CUBIC FEET PER SECOND (cfs)
5/10/19 17.25 feet 60 60 N/A 78,000 cfs
5/11/19 16.80 feet 10 70 N/A 82,000 cfs

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

The present conditions and updated forecasts for the Carrolton Gauge indicate the stage will remain at approximately 16.7 feet until June 4, 2019 before beginning a slow fall. The MVN indicates a crest above the Spillway will occur on May 23, 2019, the stages below the structure will be artificially controlled by the flow through the open bays.