Efforts to mend the Orchard Homes Levee are scheduled to begin March 30 when U.S. Army Corps of Engineers’ officials begin repairs to a 200-foot-long damaged segment located on the Clark Fork River in Missoula, Mont.
The $148,000 project will address scouring, erosion, sloughing and a loss of levee armor as a result of high flows in spring 2014. Damages reduced the levee’s flood defense to a two-year level of protection, or a 50 percent chance of occurring in any given year. Once repaired, the levee will be restored to a 100-year level of protection, or a one percent chance of occurrence.
Under a cost-share agreement, the Corps pays for 80 percent of construction costs and Missoula County picks up the remaining 20 percent.
Repairs to the levee, which protects a residential area, are expected to take one week and include rebuilding the levee slope and replacing rock armor for scour and erosion protection. In addition, willow stakes will be placed near water level to improve habitat.
The Corps received approval from U.S. Fish and Wildlife Service to work outside of the traditional fish window from July-September so flood protection could be restored before the spring runoff. In-water-work is expected to have minimal impact to area species.