THORNTON | A portion of the Thornton Quarry that has provided tons of limestone that was used to build structures and infrastructure across the region will soon become a reservoir to help protect the area from floods.
Officials with the Metropolitan Water Reclamation District conducted what they called the “last blast” Monday in the southwestern corner of the north half of the Thornton Quarry.
That explosion was to loosen the last 36,000 tons of rock, which will allow for excavation to turn the quarry into the Thornton Composite Reservoir.
During the past 15 years, some 4,000 explosions have enabled the removal of some 76 million tons of limestone from the quarry, Hanson Material Service operations manager Jeff Brasuell said.
The planned reservoir, according to water district board member Frank Avila, will collect floodwater and sewage that overflows from the Deep Tunnel system during heavy rains. From the reservoir, flood water would be sent to the Calumet Water Treatment Plant in Chicago.
Once treated, it would be released back into area waterways, Avila said.
Dan Repay, executive director of the Little Calumet River Basin Development Commission, said the reservoir could have a positive effect on the Little Calumet River.
“It would reduce the stress that now gets put on the river when there is heavy rain," Repay said. "It would have a significant impact.”
Edward Paesel, executive director of the South Suburban Mayors and Managers Association, said the fact the reservoir would help ease flooding in communities was a benefit.
“This is recycling and reuse at its best,” Paesel said.
The blast was done with cooperation of the U.S. Army Corps of Engineers.
“This reservoir will go a long way to alleviating flooding and improving the water flow throughout the South Side of Chicago and the suburbs," said Col. Frederic Drummond, of the Army Corps of Engineers.
“Turning a giant quarry into a giant reservoir is to the benefit of the people,” he said.
The reservoir, scheduled to be complete by 2015, is expected to have a capacity of 7.9 billion gallons of flood water.
Water district Executive Director David St. Pierre said the project would help protect 182,000 structures and 556,000 people while also protecting water quality in the Calumet River and the Cal-Sag Channel.
“This is one of the most visionary projects in our history,” he said. “This is no small plan.”
Among those officials present for the explosion, which occurred shortly before noon, were village presidents Gene Williams, of Lynwood, Bob Kolosh, of Thornton, and Rich Hofeld, of Homewood, along with an aide to Gov. Pat Quinn.