The Chicago Sanitary and Ship Canal, which connected the Great Lakes to the Mississippi River and made it possible to reverse the flow of the Chicago River, has been named to the National Register of Historic Places, state officials announced Friday.
The newly defined historic district wends through portions of Cook, DuPage and Will counties and includes dams, locks, control stations and spillways, according to David Blanchette, spokesman for the Illinois Historic Preservation Agency.
“It was a trend-setting construction project,” Blanchette said. “But it was also a very forward-thinking project that combined ship access and sanitation.”
The U.S. National Park Service on Jan. 20 approved the state’s recommendation to place the canal in the register. The measure buttresses protections in place from the Illinois Historic Preservation Agency, which already had deemed the canal a historic resource. Significant changes to the system have to be reviewed by that agency under state law, Blanchette said.
Completed in the first decade of the 1900s, the canal was the largest public works project ever undertaken at the time and various equipment and techniques used in its construction were later used in other large projects, such as the Panama Canal, according to the agency.
But it was not without controversy. Waste that had previously gone into Lake Michigan instead flowed down the Des Plaines, Illinois and Mississippi rivers past other towns and cities. By digging a 28-mile canal between the Chicago and Des Plaines rivers, engineers also breached the natural barrier between the Atlantic Ocean and the Gulf of Mexico, creating an avenue for invasive species to move between different watersheds.
In recent years, a group of Great Lakes states has been trying to have Chicago-area shipping locks closed to stop Asian carp from entering Lake Michigan. A report last month by a coalition of Great Lakes states and cities also explored strategies for installing permanent barriers in the Chicago waterway system that would re-reverse the flow of the Chicago River.