The Army Corps of Engineers expects to open the Bonnet Carre Spillway Friday afternoon.
Located upriver from New Orleans, the Bonnet Carre Spillway acts as a release valve for the Mississippi River. When the water reaches a flow of 1.25 million cubic feet per second, the Corps opens the spillway to divert some of that water into Lake Pontchartrain.
Bonnet Carre was already opened once this year -- for about 40 days beginning on February 27th. Tuesday’s opening would be the first time the spillway been used twice in the same year. David Ramirez, chief of water management for the Army Corps, said this has been a very wet year across the Mississippi River valley.
“I think they’re saying something like the most precipitation, rain and snow, that they’ve seen in 125 years,” said Ramirez. “So it’s an unprecedented amount of water that’s coming down.”
The influx of fresh water into Lake Pontchartrain has an effect on many aquatic species, which need a specific salinity ranges in order to live. Several dolphin deaths this spring were blamed on the fresh water from the first opening. A spokesperson for the Corps said one percent of mature oysters died from that event as well.
UPDATE: Due to recent rains and more in the forecast, The Army Corps advanced the opening to Friday afternoon, from Tuesday. This story has been updated to reflect that change.
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