The Corps’ Mississippi Valley New Orleans (MVN) plans to open 8 bays on the Bonnet Carré Spillway today (Monday, March 11, 2019). The MVN manages the opening of bays in order to keep the maximum flow at New Orleans 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 indicates that after today’s openings the flow being diverted through the Spillway is now approaching the maximum flow based on the projected crest.
The MVN advises the crest above the Spillway is presently forecasted to arrive on March 12, 2019. The latest maximum flow projection is 1.453 million cfs, this projection isbased on the measured flow at Red River Landing, with timing adjusted for downriver. The MVN indicates that by reducing the 1.453 million cfs with the flow through the Spillway at 203,000 cfs the targeted flow will be maintained at New Orleans (1.25 million cfs) through the operation of the flood control structure with the 200 bays opened (estimated).
BONNET CARRÉ SPILLWAY OPERATIONS
|DATE||CARROLTON GAUGE (NEW ORLEANS)||BAYS OPENED||TOTAL NUMBER OF BAYS OPENED||SPILLWAY DISCHARGE CUBIC FEET PER SECOND (cfs)|
|2/27/19||16.02 feet||28||28||23,000 cfs|
|2/28/19||16.20 feet||20||48||37,000 cfs|
|3/1/19||15.99 feet||40||88||75,000 cfs|
|3/2/19||16.00 feet||20||108||93,000 cfs|
|3/3/19||16.30 feet||0||108||95,000 cfs|
|3/4/19||16.50 feet||40||148||133,000 cfs|
|3/5/19||16.5 feet||0||148||144,000 cfs|
|3/6/19||16.6 feet||0||148||148,000 cfs|
|3/7/19||16.6 feet||20||168||169,000 cfs|
|3/8/19||16.6. feet||20||188||187,000 cfs|
|3/9/19||16.7 feet||0||188||191,000 cfs|
|3/10/19||16.75 feet||10||198||196,000 cfs|
|3/11/19||16.6 feet||8||206||204,000 cfs|
The operation of the Bonnet Carré Spillway will artificially control the crest at 17 feet (approximately) and maintain the maximum flow at New Orleans at or below 1.25 million cfs. The Carrolton Gauge is now expected to reach 17.0 feet on March 13, 2019 and to remain at that stage until March 15, 2019 before beginning a slow fall. There may be another rise in early April, either way high river conditions are expected to continue for the next month or longer.