Higher-than-average water releases from all Missouri River Mainstem System projects, including Gavins Point Dam, will continue through November, the U.S. Army Corps of Engineers announced Nov. 6.
“Gavins Point releases will remain near 80,000 cubic feet per second (cfs) for the remainder of November, to ensure flood control storage zones in all system reservoirs are emptied prior to the 2020 runoff season. This release rate is more than twice the average release for this time of the year,” said John Remus, chief of the Corps’ Missouri River basin water management division.
Runoff in all reaches except for the Fort Randall reach was above average for the month of October. The Garrison to Oahe reach runoff was over six times the long-term average, and runoff in the Gavins Point to Sioux City reach was more than 10 times the long-term average.
The 2019 upper basin runoff forecast was lowered slightly to 60.2 million acre-feet.
If realized, this runoff total would be 0.8 MAF less than 2011 (61.0 MAF), which is the highest runoff in 121 years of record-keeping. The January-October observed runoff (56.7 MAF) has already exceeded the second highest runoff, 49.0 MAF observed in 1997, with two months still remaining.