View of Tobacco Island mitigation area. Image courtesy of the Army Corps of Engineers.
"Floodplain functionality" has dramatically returned at wild lands along the Missouri River as evident at the numerous mitigation areas created by the U.S. Army Corps of Engineers during recent years.
Most of the sites adjacent to the river channel are now completely inundated by flood waters, based on river valley inundation maps prepared by the Corps.
Many of these mitigation sites including land that was formerly corn fields, which would have been inundated under current conditions along the river.
The depth of water at the mitigation sites would vary, according to Jolene M. Hulsing, a natural resources specialist with the Corps' Omaha district.
"The Corps number one concern is public safety and property," Hulsing said, "The flood will expose mitigation sites to natural processes that facilitate fish and wildlife.
"Mitigation sites serve as areas for the river to flow where it did prior to construction of navigation controls. These areas have been reconstructed to 'mimic' natural conditions. Being exposed to this rare flood event exposes the sites to pre-navigation and pre-dam flows. How the landscape responds to the flood water will be reminiscent of how the landscape functioned prior to settlement.
"It will be educational to see what the flood has done to impact these sites," she said.
A thorough evaluation of the sites will occur once the flooding has ended.
"Vegetative conditions and wetland situations will be mapped," Hulsing said.
There will most likely be damage to infrastructure at the mitigation sites, such as pumping stations, rock structure, fencing, roads, signage, etc. Hulsing said. "This will all have to be assessed after the flood water recede."
Corps officials currently have only limited access to the mitigation areas, due to inundated roads and excessive flows which severely inhibit boat or vehicular access.
Hulsing and other staff at the Missouri River Project Office have had to relocate from their headquarters at the Omaha Moorings, along Pershing Drive. Water is inside the lower buildings, but a port a dam currently is keeping water out of the Administrative office.
Local wildlife is having to adapt to the higher flows, but the river's fish and wildlife has dealt with flooding along the river for centuries. The extent of the spreading water may be a new experience for current generations, so they are being forced to adapt.
The mitigation sites from Sioux City to Rulo comprise about 22,000 acres, and are actively managed for natural uses to benefit indigenous fish and wildlife.