Be it this caused opinions to change, it didn't cause the flood. One of the big factors other than precipitation that added to the flood was the drainage of wetlands. North Dakota and Minnesota have always been renown for their prairie potholes. These temporary and permanent wetland covered the region in the 1960's. Since then the numbers have dropped from 4.9 million acres to 2.7 million acres in the later 1980's.
Wetlands act as nature's sponge, they soak up excess water and store it.
When the water table is saturated beyond normal levels, wetlands can hold the excess water till levels drop back to normal. Wetlands have been disappearing as farmers drain areas for more crop land or to plant earlier. This drainage goes to channels that feed the river and its tributaries. Over time the river volume will increase as less water is stored in wetlands. One solution offered by the Sierra Club is to restore 1.9 million wetlands along the North Dakota-Minnesota Red River Valley.