PROJECT ALERT NOTICE (IL) Flooding in IL

Date: Fri, 19 Apr 2013 09:35:27 EDT

Summary: Major flooding statewide in IL, especially in Chicago

Heavy rainfall across Illinois has caused widespread flooding. Over 7" of rain fell in some areas of Chicago over the last 48 hours, causing a rare "backflow event" of the Chicago Area Waterway System into Lake Michigan. Nine USGS gages with records over 20 years have experienced new peaks-of-record. Fifteen gages have recurrence intervals of >100 yrs (that is, <1% chance AEP), and 29 streamgages reached the National Weather Service “major” category in and around Illinois.

Nine USGS crews (14 people) are out across the state making streamflow measurements at streamgages to ensure that accurate data are being provided to the National Weather Service for flood forecasts and to emergency management officials and the public so that timely decisions can be made to protect life and property. Efforts will continue through the weekend. We have been in close coordination with the Corps, the NWS, and our state water agency using NWSChat. And we have been in frequent contact with the USGS National Flood Coordinator.



Sub-Region: Midwest; Region: Central United States