This week, Senator John Thune (R-SD) stated that the temporary levees now protecting Pierre, Fort Pierre, and Dakota Dunes, South Dakota, may need to be made permanent. Thune, a long-time climate change skeptic, admitted that those three communities could face similar flood events in the future. High, permanent levees would protect the residents of those towns from a larger, more voluminous future Missouri.Although he did not go so far as to admit climate change is a factor in the flooding, he did acknowledge that we are in a new era along the Missouri. His acknowledgment is a step in the right direction. We need to adapt to the likelihood that the Missouri River and its tributaries will carry more annual runoff in the years ahead than they did in the past.
Unfortunately, Thune’s tentative solution to higher annual flow volumes will protect the few rather than the many. Levees are an inadequate solution to a much larger, more complex set of problems. The long-term answer to flooding along the Missouri will entail fundamental changes in how we interact with the river.
In order to decrease the probability of a similar flood in the future, we first need to reach a consensus on this flood’s causes. We need to accept that human actions and structures brought on the flooding from Montana to Missouri. God did not bring the water down upon us, we did. And we did it in a variety of ways. We removed millions of acres of CRP land in the past five years throughout the Missouri Basin, which increased runoff into the river. Since the 1950s, we built houses, factories, and powerplants in the floodplain or directly on the river’s banks, which kept the river from spreading out and naturally reducing its crest. We erected a narrow, flood-prone barge channel south of Sioux City. We threw carbon into the atmosphere with reckless abandon and altered the region’s climate. We built dams and reservoirs that acted as silt traps. Those reservoirs resulted in the formation of deltas at their headwaters. The deltas contributed to flooding at Williston, Bismarck, Fort Yates, Pierre, Fort Pierre, and Niobrara. We urged the Army to keep the main-stem reservoirs high in the spring to promote a reservoir fishery and the tourism industry based on it. We legally required the Army to store water in the reservoirs in the early spring of each year to ensure a nine-foot depth in the river south of Sioux City from April 1 to December 1. We caused the Great Flood of 2011. Because we caused it, we can prevent a similar flood in the future.
A sampling of some of the solutions to future flooding includes: 1) allow the lower river from Ponca to the mouth into its 100-year former floodplain, which will reduce flood crests and protect towns, cities, and farms; 2) end the legal requirement of the Army to store water for the moribund navigation channel south of Sioux City, which will free up reservoir storage space in the spring for any approaching superflood; 3) pull back our constructs from the floodplain to lessen property damage in any future high water event; 4) provide monies to the CRP program to set aside millions of acres of highly erosive land, which will decrease runoff into the Missouri and its feeder streams and lower flood heights. These four steps alone will significantly reduce the future flood threat along the Missouri.
Levees are not the answer to flooding along the Missouri. Take for example the levee at Dakota Dunes. It raises the water level next to it because the river cannot spread out. That higher river then pours down on Sioux City neighborhoods or pushes out into Nebraska. The Missouri’s waters have to go somewhere. Keeping it out of “The Dunes” throws in into someone else’s front yard. One man’s levee is another man’s loss. The Army’s experience along the Mississippi River has shown that levees are not a solution to flooding.
Thune’s solution to the flooding is grossly inadequate when compared to the magnitude of the problems facing us along the river. He needs to think large-scale and basin-wide. His tentative levee plan will only protect a few locales. It would secure a handful of privileged citizens living in gated communities. It would do nothing for those without levees or the financial means and political connections to have levees built. Thune needs to propose solutions to the flooding that benefit all of us.