CNT In the News

Chicago has an urban flooding problem. The latest report on this issue, released by the Environmental Law & Policy Center and the Chicago Council on Global Affairs in March, found that climate change in the Great Lakes will result in an increase in “extreme precipitation,” heavy rainfalls that are more likely to lead to flooding. This report is only the latest in a series that have sought to quantify the problem of urban flooding in Chicago, and its disproportionate impact on the South Side. In the wake of this report’s release, the Weekly went through literature on urban flooding, and pulled out the most important numbers that describe the problem.

Across the country, the Federal Emergency Management Agency (FEMA) estimates that twenty to twenty-five percent of all economic losses from flooding occur in areas that are not designated as a floodplain—instead, these losses are the result of urban flooding. In Illinois, that number is much larger, with the Illinois Department of Natural Resources (IDNR) finding that over ninety percent of urban flooding claims in the state between 2007 and 2014 occurred outside the mapped floodplain. In Illinois, in other words, the vast majority of flooding damage doesn’t come from rivers overflowing; instead, it comes from urban landscapes and sewer systems unable to cope with rainfall, causing water to back up into streets and basements. In Cook County specifically, the Center for Neighborhood Technology (CNT) found zero correlation between whether a ZIP code is located in a FEMA-designated floodplain and the amount of flooding in that ZIP code.