Replacing a failing groundwater supply with a reliable source

City of Joliet Alternative Water Supply Program

The City of Joliet is aiming to replace a failing groundwater supply with a reliable Lake Michigan source by 2030. They engaged our team to support initial evaluations, then retained us to guide final assessments and now oversee development, engineering, coordination, financing, and outreach for a new regional water system.

During Phase I, we assessed 14 water sources across groundwater, river, and lake types. In Phase II,  we refined this down to five alternatives, focusing on water quality, quantity, sustainability, risk, and control. Ultimately, the City selected the Lake Michigan source with two intake options.

The infrastructure for this project includes a new connection to Chicago’s water system, 59 miles (95 kilometres) of transmission main, three pump stations, storage facilities, and delivery stations. The system is designed for 60 million gallons per day, or MGD (227 million litres per day, or MLD), capacity with future expansion to nearly 100 MGD (379 MLD).

Our team has achieved a number of milestones to date. These include negotiation of a preliminary water supply agreement with the City of Chicago, receipt of water allocation permits, and substantial infrastructure funding. There was also state legislation updating elements of the statutes governing the creation and operation of water commissions in Illinois. Additionally, we helped the City obtain approval for up to $700 million of funding through the U.S. Environmental Protection Agency’s Water Infrastructure Finance and Innovation Act (WIFIA) program.

Overall, the Alternative Water Supply Program involves converting the local system from distributed groundwater to centralized surface water delivery, creating program-level standards, integrating sustainability, and engaging disadvantaged business enterprises.

When complete, the new supply with serve over 385,000 people.