CHICAGOLAND UNDERFLOW
OWNER: US Army Corps of Engineers - Chicago District
LOCATION: McCook, IL
VALUE: $60 Million
The Chicagoland Underflow Project - McCook Reservoir was awarded to Kenny Construction by the Corps of Engineers in September 2002. The reservoir system was designed to reduce flooding in the Chicago metropolitan area by providing storage of excess runoff during storm events. The reservoir will contain major storm and flood events that overfill the TARP Mainstream Tunnel System.
The McCook Valve Chamber will control flows in both directions between the Reservoir and the Mainstream Pump Station at times when the tunnel system is overcapacity.
Work consisted of constructing two 11.5 feet and two 8.5 feet I.D. concrete-lined tunnels approximately 3,320 and 850 feet in length, respectively; concrete/steel bulkheads; 11.5 feet I.D. concrete-lined access shaft; 60 foot wide by 100 feet long underground chamber with a 26 foot I.D. access shaft approximately 340 feet deep and a 12 foot diameter shaft approximately 320 feet deep for ventilation; six 60 inch conical plug valves; four 5 foot bonneted slide gates; 40 foot by 60 foot control (service) building at the ground surface; and site work, excavation, site grading, utilities, and final landscaping.