Gavins Point Dam

Water flows through the spillways of Gavins Point Dam in Yankton, South Dakota, in April. After near-record runoff in April, Gavins Point releases will remain above normal, the U.S. Army Corps of Engineers said Monday.

OMAHA -- Releases from Gavins Point Dam will remain above normal while the U.S. Army Corps of Engineers continues to evacuate near-record runoff from Missouri River reservoirs.

April runoff in the upper river basin above Sioux City was 7.8 million acre-feet, the third highest April total in 121 years of record keeping. Average April runoff is 2.9 MAF.

Gavins Point releases will remain at 55,000 cubic feet per second, above the normal level of about 30,000 cfs for this time of year, John Remus, chief of the corps' Missouri River Water Management Division in Omaha, said in a news release.

"We will maintain Gavins Point releases at this rate to continue evacuating water from (upriver reservoirs) Oahe and Fort Randall, which are using much of their respective flood storage," Remus said.

Releases are expected to be above average for the next several months, possibly as late as November, the corps said.

April's above-average runoff followed a March record of 11 MAF to combine for the highest March-April runoff total (18.8 MAF) since record keeping began in 1898.

The corps has raised its 2019 runoff forecast to 42.3 MAF, which would be the third-highest recorded total. Runoff in 2018 was 42.1 MAF, and the record is 61 MAF in 2011.

As of Monday, the amount of water stored in the Missouri River's six reservoirs is at 64.7 MAF, occupying 8.6 MAF of the 16.3 MAF of flood storage capacity.

Mountain snowpack has peaked and begun melting, running off into Fort Peck reservoir in Montana and Garrison reservoir in North Dakota. Remus said both reservoirs have adequate flood control space to manage the snowmelt runoff.

Mountain snowpack was slightly above average this year, the corps said.

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