The May runoff forecast for the Missouri River basin has declined slightly. According to the U.S. Army Corps of Engineers, runoff into the Missouri River system above Sioux City, Iowa, is now expected to total 20.0 million acre feet of water. That compares to 20.5 maf in April
Predictions of water levels during the coming months for Lake Sakakawea have changed very little despite the expected decrease in overall runoff. Lake Sakakawea is projected to peak at 1,831.3 feet at the end of July. The April outlook called for a peak of 1,831.2 feet on July 31.
The level of Lake Sakakawea was 1828.2 feet Thursday, about a foot less than was projected a month ago. The current forecast shows Sakakawea raising only a few inches during May.
The reservoir remained encased in ice Thursday and, by all appearances, an ice free reservoir remains several days away. 2013 is already one of the latest years ever on Sakakawea in terms of ice cover.
May 4, 1965, ranks as the seventh latest ice free date in reservoir history. Other records that seem likely to be snapped are May 5, 1972 and 1975; and May 6, 1996 and 1997. According to the Corps, those dates rank 4-7 as the latest "ice free" dates in records kept since 1962. The latest declaration of Sakakawea becoming ice free occurred on May 17, 1979.