Runoff in the Missouri River Basin above Sioux City, Iowa, for the month of July was 2.7 million acre feet (MAF), 81 percent of normal. The 2015 runoff forecast is 25.0 MAF, 99 percent of normal. Average annual runoff is 25.2 MAF.
The total volume of water stored in the Mainstem Reservoir System is currently 61.3 MAF, occupying 5.2 MAF of the 16.3 MAF combined flood control storage zones. System storage peaked on July 9 at 61.9 MAF and is gradually declining. The water currently stored in the annual flood control zone will be released during the remainder of the year to serve navigation, water supply and other downstream purposes and will be completely evacuated prior to the start of next year’s runoff season.