(NAFB) – Water conservation measures were enacted for the second half of the Missouri River navigation flow support season.

The U.S. Army Corps of Engineers Thursday said very dry conditions continue to impact the upper Missouri River basin above Sioux City, Iowa, despite recent heavy rainfall in the lower basin, with more rainfall in the forecast south of Sioux City. As a result of the low precipitation and widespread drought conditions in the upper basin, June runoff in the upper basin was 52 percent of average.

The updated 2021 upper basin runoff forecast is 15.6 million acre-feet, 60 percent of average, the tenth driest year in the upper basin since 1898. USACE reduced the service level to support navigation by 1,500 cubic feet per second at Gavins Point dam.

USACE Missouri River Chief John Remus says the reduction “is a necessary water conservation measure to ensure authorized purposes will be served in the short and long term.”