Text Box: The first few months of 2008 was a traditional Chicago winter. Cold temperatures and generous snow resulted in record spreading of rock salt on area roads. In fact, some municipalities were caught off guard and ran out!

Where did all of that salt eventually go? It melted, of course, and then drained into storm sewers, which flow into the nearest river.

Click on the three tabs below to see the dramatic levels of Chloride in Salt Creek and the East & West Branches of the DuPage River during the winter of 2008.