World’s Largest Storm Reservoir
And that’s only a small fraction of its 7.9 billion-gallon capacity. The Metropolitan Water reclamation District of Greater Chicago said the new stormwater reservoir is the largest in the world.
It serves as an escape hatch when Chicago’s Deep Tunnel system fills to the brim, which happens during some heavy storms. It will help stop stormwater tainted with sewage from running into lake Michigan and other area waterways, as well as flooding basements.