It has been nearly 120 years since the Sanitary District of Chicago reversed the flow of the Chicago River. The agency, now called the Metropolitan Water Reclamation District, is still engineering immense water control projects. Its latest modern marvelwill have a significant impact on flood control in the area.

It’s being called the Grand Canyon of the Midwest—but on a vastly smaller scale. Still, at 3,000 feet long and 310 feet deep, the McCook Reservoir is an impressive sight. It’ll be put into service later this year and has the capacity to hold 3.5 billion gallons of stormwater. That’s a lot of rainfall that officials say won’t be accumulating on Chicago-area streets and in basements.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Stage one of the McCook Reservoir will be completed later this year with a holding capacity of 3.5 billion gallons of stormwater.

Public tours

The MWRD hosts free public tours of theof the first phase of the McCook Reservoir on select Sundays (Sept. 17 and 24; and Oct. 1 and 15) between 9 a.m. and 2 p.m. Tours last about 2 hours and include bus transportation to theMcCook Reservoir. Tours begin at theMainstream Pumping Station, 6100 River Road, Hodgkins. Appropriate dress includes sturdy footwear (no sandals, high heels) and no shorts or dresses, please. Reservations:312-751-6632 or[email protected].

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