Combined Sewer Overflow Waterway System
  The District has developed GIS software to track CSO occurances in reaches of the Chicagoland waterway system. These are reported by the individual point where the CSO occurances take place. This tool can be used to view CSO occurances on a map represented by an red dot. Current CSO occurances are displayed on the map below. CSO occurances that have occured on a prior date can be viewed by selecting a date from the list and clicking "View Map". Please ensure your popup blocker is disabled for this site in order to view the map.
Current CSO Event(s):

Larger Version

NOTE: Current CSO events are events that occur between
12:00 AM and 11:59 PM of the current day

Prior date with CSO events:
  Note: The information presented in the above maps is updated frequently and reflects CSO and diversion activity based on the best available data. Not all CSO outfalls are equipped with monitoring equipment. Therefore, other CSOs may have occurred that are not reflected on the above map. Regardless of CSO activity, the Chicago Area Waterways may contain disease-causing bacteria at any time. Therefore, swimming, canoeing, or other activities where immersion in water is possible should be avoided and is not recommended, particularly during and immediately following rainfall.