System storage is 56.7 MAF; 0.6 MAF of the 16.3 MAF of flood control storage is occupied. About 96% of the flood control storage is available to store runoff this spring and summer. Heavy plains snow remains in the northern half of South Dakota and central North Dakota (upper right graphic). The National Weather Service is forecasting high flows on the Big Sioux, Vermillion, and James Rivers from melting snowpack