Study focuses on Missouri River vulnerabilities

A study released by the U.S. Army Corps of Engineers Monday says the agency did what it could to manage the historic 2011 flooding on the Missouri River, but that more repairs, research and monitoring are needed to mitigate damage in future high flow years.

Experts from the Corps of Engineers conducted the study, which focuses on vulnerabilities that remain after the Missouri River rose to record levels last year.

The flooding began after the corps began releasing massive amounts of water from upstream reservoirs that had been filled with melting snow and heavy rains. The onslaught lasted for more than 100 days, busting levees, carving gouges up to 50 feet deep and dumping tree limbs, pieces of children?s swing sets, gas cans and other debris on farmers? fields.

The corps says about $400 million will be spent to fix damage along the Missouri River caused by the 2011 flooding. Most of the levee repairs are expected to be completed before next spring, with work on the dams expected to take longer.

An issue that is being examined is whether efforts to create more shallow-water habitat to help wildlife contributed to levee damage.

The study found that more monitoring is needed, and the corps says it needs better information about such things as the frost depth of the soil and the water content of the snow. The agency wants details about how runoff is affected by a wetlands area in the Dakotas known as the prairie pothole region.

The corps is collaborating with several groups to enhance data collection and forecasting. Among the ideas is establishing more permanent plains snow measurement stations.

The study also says more water gauges are needed on the Missouri River. It notes that between 1990 and 2010, 387 gauges that once were monitored by the U.S. Geological Survey were discontinued. Seventeen other gauges now provide less information.

Reducing Missouri river and tributary flow measurements decrease the accuracy of forecasts used to operate the system, according to the study.