The City of Des Moines, Iowa, is undertaking a multi-phase project known as the Des Moines Levee Alterations Project (DMLAP) modify the city's levee systems on the Des Moines and Raccoon Rivers that do not meet FEMA levee accreditation requirements as outlined in 44 CFR 65.10. The primary goal of the project is to bring the levee systems into compliance with these FEMA requirements, obtaining FEMA accreditation and reducing the risk of flooding to surrounding communities.
Barr is providing detailed design and construction management to support several phases of the DMLAP. Improvements include raising the crest elevation of select levees and floodwalls, modifying gatewell structures, enhancing temporary closure structures, improving embankment protection measures, assessing geotechnical stability, constructing seepage mitigation measures, and addressing deficiencies identified by the US Army Corps of Engineers (USACE).
Our diverse geotechnical experience and expertise have been valuable during critical project phases involving geotechnical challenges. Our project team conducted a thorough assessment of the geotechnical conditions to ensure the stability of the levees and structures and to implement appropriate mitigation measures. Seepage mitigation has included a seepage relief trench system, which eliminates the need to relocate extensive utility infrastructure.
We coordinated design and construction to meet USACE’s guidance. This includes obtaining the necessary USACE permits, such as those related to Section 404 and 408, which govern wetland impacts and alterations to levees.
The successful completion of the DMLAP will result in an improved flood risk management system that meets FEMA's accreditation requirements. By bringing the levee systems into compliance with 44 CFR 65.10, the project will enhance the overall resilience of the City of Des Moines, further protecting its residents and infrastructure from flooding.