Location: Chicago, IL
Application: Detention and Rainwater Harvesting
Product used: 5’-6” SingleTrap
Number of pieces: 19, 18
Number of systems: 2
Total water stored: 10,029.19 ft3, 8,988.06 ft3
Project Details: A design concept made by James Corner and his team of James Corner Field Operations aimed to rework the Pierscape. John P. Fehlberg, P.E., of Primera Engineers, says they wanted to “make it more publicly accessible, more like an urban park and a little bit less like a carnival or an amusement park.” The stormwater element of the project was critical because the Pier is located at the junction of the Chicago River and Lake Michigan. The project was separated into two different basins. The first basin would focus on rainwater detention while the second would be used for rainwater harvesting.
Challenges: One of the challenges with rainwater harvesting was to make sure that the water being used for plant irrigation was not polluted. Another challenge was that the site had to remain open during the project, and they could only close small areas at any given time. Furthermore, a variety of challenges arose due to the nature of the pier structure itself. Fehlberg details, “There is no ground beneath the pier. It’s a structure supported over the water. It’s difficult to run water lines that carry the harvested water to the irrigation points.” There were also multiple unknown underground obstructions found during construction due to the piers history that the team had not been planning on.
Solution: In order to ensure clean harvested water, Fehlberg says the team was “very selective” and they “separated the roadway drainage into the detention system and tried to capture runoff from areas where it was deemed that the runoff would be a little cleaner.” StormTrap was also able to “minimize the construction footprint during the high tourist season.” Fehlberg explains that the unknown underground obstructions “required several revisions to the layout of the underground stormwater management and rainwater harvesting chambers on the fly during construction. The modular nature of the StormTrap system helped adapt to and overcome these surprises efficiently, and made StormTrap a good fit for this challenging application.”