The Corps’ Mississippi Valley New Orleans (MVN) did not open any bays on the Bonnet Carré Spillway (Mile 128.8 to 127.3 Above Head of Passes [AHP]) today (Monday, June 3, 2019). The maximum flow above the Bonnet Carré today was 1.224 million cubic feet per second (cfs) based on the flow measured at Red River Landing (Mile 302.4 AHP), with the calculations and timing adjusted for the downriver flow at Bonnet Carré. The flow and stages have receded over the last ten days, but the next rise is predicted to begin this Friday, June 7, 2019.
UPDATE: The operation of the Morganza Floodway (Spillway) at Mile 280 AHP is now scheduled to occur on Wednesday, June 12, 2019:
“Preparations are underway for the slow opening of the Morganza Floodway scheduled to begin 12 June (second rescheduling), based on very high stages predicted at the structure, coupled with the potential for even higher stages/river flow over the longer term. Changing conditions upstream and a revised forecast have prompted the schedule change.”
The predicted crest above both Spillways is forecast to occur between June 14 to June 23 (2019).
BONNET CARRÉ SPILLWAY SECOND OPERATION 2019
|DATE||CARROLTON GAUGE (NEW ORLEANS)||BAYS OPENED TODAY||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|
|5/12/19||16.80 feet||0||70||N/A||79,000 cfs|
|5/13/19||17.00 feet||58||128||N/A||116,000 cfs|
|5/14/19||16.75 feet||10||138||N/A||127,000 cfs|
|5/15/19||16.70 feet||0||138||N/A||127,000 cfs|
|5/16/19||16.60 feet||0||138||N/A||122,000 cfs|
|5/17/19||16.60 feet||0||138||N/A||122,000 cfs|
|5/18/19||16.80 feet||0||138||N/A||127,000 cfs|
|5/19/19||16.90 feet||10||148||N/A||142,000 cfs|
|5/20/19||16.80 feet||0||148||N/A||148,000 cfs|
|5/21/19||16.80 feet||20||168||N/A||161,000 cfs|
|5/22/19||16.80 feet||0||168||N/A||161,000 cfs|
|5/23/19||16.80 feet||0||168||N/A||158,000 cfs|
|5/24/19||16.70 feet||0||168||N/A||155,000 cfs|
|5/25/19||16.70 feet||0||168||N/A||155,000 cfs|
|5/26/19||16.60 feet||0||168||N/A||152,000 cfs|
|5/27/19||16.60 feet||0||168||N/A||157,000 cfs|
|5/28/19||16.60 feet||0||168||N/A||157,000 cfs|
|5/29/19||16.60 feet||0||168||N/A||149,000 cfs|
|5/30/19||16.60 feet||0||168||N/A||145,000 cfs|
|5/31/19||16.50 feet||0||168||N/A||140,000 cfs|
|6/1/19||16.50 feet||0||168||N/A||140,000 cfs|
|6/2/19||16.50 feet||0||168||N/A||140,000 cfs|
|6/3/19||16.50 feet||0||168||N/A||140,000 cfs|
The stages below the Spillway(s) will be artificially controlled by the flow diverted from the Mississippi River through the open flood control structures.
The MVN manages the opening and closing of bays on the Bonnet Carré Spillway as a flood control structure 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) in accordance with the approved Bonnet Carré Spillway Water Control Manual. The stages at the Carrollton Gauge are expected to remain steady at approximately 16.7 feet
The Morganza Floodway Structure is operated based on a trigger point flow of 1.5 million cubic feet per second at Red River Landing and under stage conditions designed to protect the flood control structures. The operation of the Spillway structures is expected to continue through late-June to early-July.
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 and the Great Flood of 2019 continues to be record setting.