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Metropolitan Water Reclamation District of Greater Chicago

Over a half inch of rain has fallen today in some locations in Cook County, and weather forecasters anticipate an additional inch of rain tomorrow. As the rain descends upon the area, the Metropolitan Water Reclamation District of Greater Chicago’s (MWRD’s) Tunnel and Reservoir Plan (TARP), which is comprised of three systems, is operating as designed.

Combined, the tunnels and reservoirs are holding more than 4 billion gallons of water. The current status of all TARP tunnels and reservoirs includes:

Kirie TARP Status
The Kirie TARP system includes a tunnel and Majewski Reservoir.
Kirie Tunnel is 1% full = 0.44 Million Gallons (MG)
Majewski Reservoir = 0% full

McCook TARP Status
The McCook TARP system is comprised of the Mainstream Tunnel, Des Plaines Tunnel, and McCook Reservoir.
Mainstream Tunnel is 5% full = 65.7 MG
Des Plaines Tunnel is 1% full = 5.1 MG
McCook Reservoir is 90% full = 3.23 Billion Gallons

Calumet TARP Status
The Calumet TARP system is comprised of the Calumet Tunnel and Thornton Composite Reservoir.
Calumet Tunnel is 70% full = 441 MG
Thornton Composite Reservoir is 13% full = 1.05 Billion Gallons

Before severe storms, the MWRD lowers the levels of the Chicago Area Waterway System. We are working around the clock to manage the excess water coming into our seven water reclamation plants. We encourage the public to reduce their use of water during rain events; wait to run the dishwasher, shower and/or do the laundry.

Storm Update_071123.pdf

Press Release

Established in 1889, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) is an award-winning, special purpose government agency responsible for wastewater treatment and stormwater management in Cook County, Illinois.


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