Bonnet Carré Spillway Operation 4919

The Corps’ Mississippi Valley New Orleans (MVN) plans to close between 35 to 50 bays on the Bonnet Carré  Spillway today (Tuesday, April 9, 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 reported the flow dipped below the trigger point level (less than 1.25 million cfs) on Friday, April 5, 2019.

Today’s maximum flow projection is 1.169 million cfs, this projection is based on the measured flow at Red River Landing, with calculations adjusted for downriver.      

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, approximately 50 of the 350 bays will be opened at the end of the day. During the recorded crest 206 bays were open and the maximum flow at Red River Landing was estimated to be 1.455 million cfs.

                                                                                                    BONNET CARRÉ  SPILLWAY OPERATIONS       

DATE CARROLTON GAUGE (NEW ORLEANS) BAYS OPENED TOTAL NUMBER OF BAYS OPEN TOTAL NUMBER OF BAYS CLOSED SPILLWAY DISCHARGE CUBIC FEET PER SECOND (cfs)
2/27/19 16.02 feet 28 28 N/A 23,000 cfs
2/28/19 16.20 feet 20 48 N/A 37,000 cfs
3/1/19 15.99 feet 40 88 N/A 75,000 cfs
3/2/19 16.00 feet 20 108 N/A 93,000 cfs
3/3/19 16.30 feet 0 108 N/A 95,000 cfs
¾/19 16.50 feet 40 148 N/A 133,000 cfs
3/5/19 16.5 feet 0 148 N/A 144,000 cfs
3/6/19 16.6 feet 0 148 N/A 148,000 cfs
3/7/19 16.6 feet 20 168 N/A 169,000 cfs
3/8/19 16.6. feet 20 188 N/A 187,000 cfs
3/9/19 16.7 feet 0 188 N/A 191,000 cfs
3/10/19 16.75 feet 10 198 N/A 196,000 cfs
3/11/19 16.6 feet 8 206 N/A 196,000 cfs
3/12/19 16.8 feet N/A 206 N/A 196,000 cfs
3/13/19 16.8 feet N/A 206 N/A 202,000 cfs
3/14/19 16.7 feet N/A 206 N/A 204,000 cfs
3/15/19 16.7 feet N/A 196 10 196,000 cfs
3/16/19 16.8 feet N/A 196 0 199,000 cfs
3/17/19 16.9 feet N/A 196 0 204,000 cfs
3/18/19 16.8 feet N/A 196 0 207,000 cfs
3/19/19 16.9 feet N/A 196 0 207,000 cfs
3/20/19 16.8 feet N/A 196 0 210,000 cfs
3/21/19 16.8 feet N/A 196 0 196,000 cfs
3/22/19 16.7 feet N/A 196 0 194,000 cfs
3/23/19 16.7 feet N/A 196 0 193,000 cfs
3/24/19 16.6 feet N/A 196 0 185,000 cfs
3/25/19 16.6 feet N/A 196 0 177,000 cfs
3/26/19 16.5 feet N/A 176 20 158,000 cfs
3/27/19 16.6 feet N/A 152 24 132,000 cfs
3/28/19 16.6 feet N/A 135 17 131,000 cfs
3/29/19 16.7 feet N/A 135 0 131,000 cfs
3/30/19 16.8 feet N/A 135 0 131,000 cfs
3/31/19 16.8 feet N/A 135 0 131,000 cfs
4/1/19 16.8 feet N/A 135 0 135,000 cfs
4/2/19 16.7 feet N/A 135 0 126,000 cfs
4/3/19 16.5 feet N/A 135 0 114,000 cfs
4/4/19 16.5 feet N/A 135 0 107,000 cfs
4/5/19 16.3 feet N/A 135 0 101,000 cfs
4/6/19 16.2 feet N/A 135 0 94,000 cfs
4/7/19 16.0 feet N/A 135 0 86,000 cfs
4/8/19 16.0 feet N/A 99 36 61,000 cfs
4/9/19 15.8 feet N/A Unknown 35-50 37,000 cfs

 

The present conditions and updated forecasts for the Carrolton Gauge indicate the stage will remain at approximately 15.9 feet until April 20, 2019 before beginning a slow fall.  These forecasts are complicated by taking into account the plans to close additional bays at the Bonnet Carré Spillway on a daily basis, the stage forecast for May 7, 2019 is 14.4 feet.

 

The MVN expects all bays will be closed by April 12, 2019.