The Stickney Water Reclamation Plant in Illinois is one of the largest wastewater-treatment facilities in the world, serving about 2.3 million people and cleaning an average of 700 million gallons of wastewater a day. During rainfall, the facility can handle a whopping 1.44 billion gallons of wastewater in a single day — that's a million gallons every minute.
The clean water is released into the Chicago Sanitary and Ship Canal, and the sludge that is removed from the water is converted to biosolids, which are a sustainable alternative to chemical fertilizers.

For more, visit: https://mwrd.org/what-we-do