Restoring an Urban River Corridor to Reduce Flood Risk: The Western Milwaukee Project

The Milwaukee Metropolitan Sewerage District (MMSD) is undertaking a project to transform a 1.3-mile reach of river and floodplain from industrial land use development to open green space. The project will provide increased conveyance and storage along with stormwater and environmental benefits within the City of Milwaukee and the City of Wauwatosa. In response to major flooding events in 1997 and 1998, the MMSD developed comprehensive plans to reduce the risk of damage to property and loss of life along the rivers and streams in the Milwaukee area. The Western Milwaukee project serves as the final piece of the Watercourse Management Plan for the Menomonee River, which also includes added storage upstream, floodwalls and levees along the river and stormwater control regulations. The Western Milwaukee project must tie together seven other improvement projects currently designed or constructed so that the system provides adequate flood management throughout the lower Menomonee River. In addition to a lowered floodplain and conveyance improvements for high-flow events, the project will include the construction of earthen levees, concrete floodwalls and gravity pipelines within an interior drainage area. Stormwater best management practices will be included where appropriate to provide water quality improvement. The project area includes an old industrial corridor that poses several challenges, including working around a functional trans-continental rail line, likely environmental contamination, and the acquisition of real estate. The Cities of Milwaukee and Wauwatosa, as well as Milwaukee County, will play active roles in assisting in determining the future use of the area. This paper describes several aspects of the hydraulic and ecological design and presents the initial concepts developed to meet the project objectives.