


Combined sewer overflows cause water quality problems in Longfellow Creek. We helped fix this problem by designing green stormwater infrastructure (GSI) retrofits for thirteen blocks of right-of-way to improve water quality and reduce stormwater volumes discharging to the creek. Bioretention facilities, intersection bioretention bulb-outs, and permeable pavement sidewalks integrate with sidewalk and ramp reconfigurations to achieve these improvements and ADA compliance. Underdrains collect and convey treated stormwater from the planters to a simplified injection well (drilled drain) for deep infiltration. We designed the project in partnership with a neighborhood greenway project in the Delridge neighborhood. Together, the projects enhance pedestrian mobility, increase traffic safety and improve water quality.