Lake Michigan Inundated with 90+ Billion Gallons of Storm Water

By Margaret Lyons in News on Sep 16, 2008 6:10PM

Over 90 billion gallons of storm runoff water rushed into Lake Michigan this weekend in an attempt to slow or prevent further flooding. A typical heavy rainstorm in the Chicago area brings between 3 and 4 inches of rain in a day; this weekend, parts of Chicagoland saw more than 9 inches of rainfall in a day. Chicago's water management systems aren't built for these kinds of storms, and the "deep tunnel," which holds 2.5 billion gallons of water, was full by 7:30 a.m. Saturday.

According to this lucid and surprisingly interesting story from Metropolitan Water Reclamation District of Greater Chicago's board member Debra Shore, the storms were so severe that "the MWRD was compelled to employ its last resort—opening the system of three gates and locks at Wilmette Harbor, at the mouth of the Chicago River near Navy Pier, and at the O'Brien lock on the south side of Chicago, to discharge stormwater overflow into Lake Michigan." It's a last resort because storm water also contains some "highly-diluted sewage." The Chicago Department of Water Management spokesman said there hasn't been a drop in water quality, so fear not. [ChuffPo, Trib, photo by rjseg1]