CHICAGO (AP) -- The storm-swollen Chicago River is being allowed to flow into Lake Michigan to relieve flooding and sewer backups downtown and in neighborhoods.
The river was diverted away from the lake more than a century ago to keep pollution out of the lake, the source of the city's drinking water.
But Metropolitan Water Reclamation District spokeswoman Allison Fore says three locks were opened early Thursday morning to "re-reverse" the flow into the lake because huge tunnels and reservoirs designed to hold storm water were full or near capacity.
Fore says the city's four tunnels can hold 2.3 billion gallons of water, but the two largest were full by 3:30 a.m. A storm water reservoir near O'Hare was 70 percent full.
More than 5 inches of rain has fallen in the area.