Chicago’s Green Alley Project Handbook
The Green Alley Program is a new approach to Chicago’s existing alley program. Alleys provide a great benefit for the City, but like all infrastructure, they also require maintenance and periodic reconstruction. Flooding is often an issue in alleys because many alleys in the City were built without a connection to the City’s combined sewer and stormwater system.
While one solution to this problem is to install expensive connections to the City sewer system, the Green Alley Program also looks at other more sustainable solutions.
In particular, where soil conditions are appropriate, water is allowed to infiltrate into the soils through permeable pavement or infiltration basins, instead of being directed into the sewer system or onto adjacent property. This not only solves a persistent problem, but it also provides an environmental benefit by cleaning and recharging the ground water. Furthermore, by not sending additional water to the combined sewer system a green alley can help alleviate basement and other flooding issues.
This handbook explains the innovative technologies the city will use to green the alleys, including permeable, high albedo concrete with recycled materials, energy efficient dark-sky lighting, and residential and commercial improvements to work with owners of adjacent properties.
