Constrained with limited green space, marginal tree canopy overhead and inadequate room for infrastructure below the streets, engineers must be creative when considering where to collect and contain stormwater when rain is pelting streets at intense rates. This was the case on July 2, 2023, when as much as nine inches of rain fell on the West Side of Chicago in a matter of hours. The storm led to devastating flooding and years of recovery.

Collaboration is key to protecting West Side from flooding

Already partnering with the Chicago Department of Water Management (DWM) on various stormwater management initiatives throughout Chicago, engineers with the MWRD immediately went to work to assess how to best address more storage capacity for the West Side. Together, they came up with an innovative solution that utilizes underground infrastructure to accommodate stormwater under side streets to give sewers more capacity to handle the flow.

Flood storage waiting in the wings

Known as wing storage, this underground detention structure is constructed from large box culverts and located under residential streets fronting 330-foot half-block sections where major utilities are absent. These box culverts, that are as large as 12 feet by 12 feet, are designed to temporarily capture excess stormwater and help prevent street and basement flooding when capacity of local sewers is exceeded. The box culverts attach to the local trunk sewer at the downstream end, while connecting each other under the street.

Finding room and identifying a location

DWM and MWRD engineers identified two locations where they could find instant volume capture. They selected Maypole Avenue between Cicero and Lavergne avenues in the 28th Ward and Le Moyne Street between Luna and Lorel avenues in the 37th Ward and. The MWRD Board of Commissioners authorized the MWRD to enter into an intergovernmental agreement with the DWM to fund up to $6 million toward the two projects. The underground storage system will complement ongoing citywide initiatives to improve drainage and bolster climate resilience while advancing environmental equity.

Making an impact on stormwater management capacity

The two wing storage projects combined will provide nearly 1.7 million gallons of stormwater storage and flood protection to more than 2,900 homes and businesses in both North and South Austin and portions of West Garfield Park and Galewood in the 28th, 29th and 37th wards on Chicago’s West Side. These are examples of projects that were identified through continued collaboration between MWRD and the DWM that began with previous stormwater master planning efforts and are now culminating in tangible solutions. This critical initiative also aims to enhance stormwater management, reduce flooding, and support the MWRD’s and the City of Chicago’s commitment to sustainable and equitable infrastructure, following the devastating storms that inundated the West Side in July 2023.