Missouri Basin River Forecast "The graphic above shows where recent river gage forecasts are available, and are colored according to their values. They are the most recent guidance forecasts we have issued as of the date/time stamp on the bottom of the graphic." CLICK IMAGE TO GO TO INTERACTIVE MAP (image: NOAA)

In 1804 and 1805, Lewis and Clark made history with their trip up the Missouri River, but it’s the waters coming down the Missouri that will make history in 2011. People along the Missouri are thinking less of Lewis and Clark and more about Noah these days.

Here’s what’s happening on the Missouri River, as it moves downstream from Montana. The National Weather Service water gauge at Wolf Point MT hit an all-time record high water mark this morning. Williston ND passed its old record flood levels on Tuesday, and the waters are expected to continue rising through at least next Monday or Tuesday (with still more snow to melt in the mountains . . .) . In Greenwood SD, the flood waters are about 6 feet above the old record, in Verdel and Niobrara, they are 3 feet above the old record, and Springfield has topped its old mark by 2.5 feet.

Which brings us to the Gavins Point Dam. This dam (like others along the Missouri) has been critical in holding back a lot of runoff, but now it’s almost at its limit. Officials are releasing more and more water from the dam, plateauing next Tuesday at record levels and continuing as long as the rains and snowmelt continue upstream. Right now, the Army Corps of Engineers expects these record releases of water to last four to six weeks — and maybe longer.

Towns downriver from there are extremely worried about next month or so. Right now, things are bad enough, and they’re only going to get worse as the flows over the Gavins Point Dam increase and stay at that very high level. Gayville SD is five feet above their record already, and Maskell is 2.5 feet above their historic high water mark.

And its not just the Missouri River that everyone is worried about. When the Missouri gets this high, it means that all the smaller rivers, streams, and creeks that usually flow into it can’t. The water backs up into these rivers, causing flooding along their banks. The James River, for instance, flows into the Missouri just below the Gavins Point Dam, and the manager of the James River Water Development District is keeping one eye on the James and another on the skies (emphasis added):

“The biggest concern for the lower James will be any future heavy rains in the basin while the Missouri is still high. The runoff from these rains would cause additional pooling or backwater at the lower end of the James.” . . .

Raschke plans to visit Yankton County next week to review the flooding threat at the mouth of the James River.

He doesn’t know what he will find when he arrives.

“We have never had this (historic) flooding before,” he said. “We have no idea what 150,000 cfs is like. That’s 1.1 million gallons a second.”

In Montana, emergency work right now means bringing food and medicine by boat to people stranded by the floods. Further down the Missouri River, cities in Iowa, Nebraksa, Kansas, and Missouri are not looking at record water levels yet, but they know they will get there. In Iowa and Nebraska right now, emergency work means preparing people for evacuations, stockpiling supplies that will be needed when the flood waters arrive, and raising rail road beds to keep some train lines open. In Omaha, the city’s Public Works Department has worked for two weeks in 100 degree heat to raise the levee around their sewage treatment plant in anticipation of record high water in the Missouri River — sacrificing passenger rail service to Omaha in order to preserve the water system.

It’s going to be a long, wet summer along the Missouri.