A draft environmental assessment for levee repairs along the left–descending bank of the Missouri River and at one levee station along Upper Pony Creek in Mills and Pottawattamie counties, Iowa is currently available for public review, USACE reports.
The draft EA evaluates the environmental impacts of repairing damage to the levees caused by multiple heavy rainfall events in the summer and fall of 2018.
The project would include repairing damaged relief wells at two locations along the Missouri River in Iowa and constructing two small piggyback levee sections along Upper Pony Creek near the L31/192nd Bridge to address bank sloughing.
Repairs will be completed under the Corps’ PL 84-99 Emergency Levee Rehabilitation Program, said USACE’s Omaha District in its latest release.
Background
Multiple heavy rainfall events occurred across west central Iowa impacting the Missouri River and Upper Pony Creek watersheds during the summer and fall of 2018.
This resulted in several periods of high flows within the Missouri River and Upper Pony Creek. During these rain events, flood waters were noted against the L-611-614 and Upper Pony Creek levee banks and heavily saturated soils on the landside of the levees.
The levee sponsor requested rehabilitation assistance in September 2018. In October 2018, USACE conducted a damage survey and found damages to two relief wells located along levee unit L-611-614 and bank sloughing along the left descending bank of Upper Pony Creek. USACE also noted in the damage survey report that the levees were in an active status and eligible for PL 84-99 assistance.
Under PL 84-99, USACE is authorized to provide rehabilitation assistance in the repair of eligible federal and locally constructed flood control works damaged by flood events.
Rehabilitation assistance is only available to projects that are in an active status at the time the flood damage occurs, and assistance is limited to the repair, rehabilitation, or restoration of projects to their pre-disaster condition and/or level of protection, said USACE.