Concern about the ability of the Chicago region's sandstone aquifers to supply drinking water to parts of the region continues to grow. The Illinois State Water Survey (ISWS) estimates that parts of our region that depend on sandstone aquifers are using water twice as fast as it can be naturally replenished. This pattern is unsustainable for many communities, including the City of Joliet, the third largest municipality in the state. Following a 2018 ISWS study that showed that Joliet would not be able to meet the demands of its residents and businesses by 2030, the city immediately initiated a detailed evaluation of alternative water supply sources. Last week, the Joliet City Council voted to begin the process to secure Lake Michigan as its water source. Read more in the Herald-News.
Following the city’s decision, CMAP reviewed the ON TO 2050 Regional Water Demand Forecast to understand the implications for the region. Although overall demand on the sandstone aquifers will be reduced, water supply challenges will remain for other groundwater dependent communities. The Illinois State Water Survey estimates that the sandstone aquifers could reliably supply approximately 65 million gallons of water per day over the long term. However, even without the City of Joliet, water demand on the sandstone aquifer is forecasted to grow to approximately 100 million gallons of water per day by 2050.
Continued efforts to protect water supplies are critical to ensuring all residents have access to high quality water into the future, especially for groundwater dependent communities. Water conservation practices, alternate sources, and better coordination between communities are just a few of the recommendations that can be found in ON TO 2050.