Chicago’s TARP plan:
Chicago’s Tunnel and Reservoir Plan (TARP) uses large tunnels to store excess water and once it’s completed, it will reservoirs that can store 17.5 billion gallons of water. TARP reduces flooding in Chicago and reduces the harmful effects of flushing raw sewage into Lake Michigan.
As of October 2005, the underground drilling and blasting was complete and reservoirs are scheduled to become operational and hold and process sewage, notably in McCook (2013 and 2019) and Thornton (2014).
TARP is planned to be fully completed in 2029 and has cost over three billion dollars in the past 30 years of construction.