There are growing signs that the water level in Lake Sakakawea will continue to drop significantly in the coming months, placing increased hopes on a big runoff next spring to recharge the reservoir.
This year was an odd one for the Missouri River system. On the heels of a very warm winter, runoff came earlier than usual. However, the amount of runoff into the system in 2012 has been below normal. The latest outlook issued by the U.S. Army Corps of Engineers projects the trend to continue through the end of this year. The October forecast lists 2012 runoff at 19.0 million acre feet. Average runoff is 24.8 MAF.
Lake Sakakawea's peak in 2012 occurred in January at 1,839.3 feet. During most years, peak elevations in the reservoir occur in July. In the record keeping period of 1967-2012 there has been only six occasions when Sakakawea's yearly peak was recorded in January. The latest was in 2004 when the reservoir stood at 1,818.4 feet in January and 1,810 feet in December.
Kim Fundingsland/MDN • Boaters enjoyed an excellent summer on Lake Sakakawea despite below-normal runoff. Current projections show the reservoir will continue to fall.
This past summer Sakakawea reached 1,838.0 feet in July, 16.6 feet less than the flood year of 2011. Only in February, one of the lightest runoff months on the calendar, did inflow into Lake Sakakawea exceed the long-term norm.
The Sept. 1 outlook projected an end of month elevation of 1,833.6 feet for Sakakawea. The reservoir stood nearly a foot below that mark Wednesday at 1,832.7 feet. September runoff was 104 percent below normal. Current projections have the reservoir dipping below 1,832 feet by the end of October with further decreases expected. The Dec. 31 elevation is now forecast to be 1,829.7 feet with the decline continuing until reaching 1,827.5 feet at the end of February 2013, more than 10 feet less than February of this year.
Large fluctuations of yearly water levels often occur on Lake Sakakawea. No problems were reported on Sakakawea due to lower than expected water levels in 2012 but a continued downward trend would push the reservoir nearer the problematic stage for recreation, community water supplies and the fishery.
There are a number of variables that can have a significant impact on future water levels in Lake Sakakawea, the foremost being runoff into the reservoir and the amount of water being released downstream.
Looking ahead to possible accumulation of mountain and plains snowpack this winter, the Climate Prediction Center is forecasting a greater than equal chance of warmer than normal temperatures in the northern United States through February 2013. The CPC also predicts that precipitation will run below normal through February 2013, over the mountain region of Montana, which supplies runoff into the Missouri River Basin, and also the headwaters region of the Yellowstone River which joins the Missouri in extreme western North Dakota.