ILLINOIS FLOW REPORT

Last Updated: February 13, 2026

In Illinois, river enthusiasts will find current streamflow conditions vary significantly across the state's waterways. A majority of rivers are experiencing below-normal flow levels, with noteworthy deficits seen in the Big Muddy River at Murphysboro and the Kaskaskia River near Venedy Station, registering streamflows at -90.76% and -94.45% of normal, respectively, indicating potential flow drought conditions. Large streamflow changes have been observed in the Cache River at Forman with an increase of over 1145% in the last 24 hours, reaching a gage height of 11.83 feet, which could raise concerns for flooding in nearby regions. Conversely, the Spoon River at Seville and the Sangamon River near Oakford have seen significant drops in streamflow, marking a decrease of -34.39% and an increase of 93.91% in the last 24 hours, respectively.

The Illinois River shows variable conditions; At Marseilles, a notable increase by 60.82% in the last 24 hours to a gage height of 11.79 feet could affect local towns and recreational activities negatively. The Rock River, with several monitoring points, has shown decreases in streamflow, such as at Byron with a -74.48% change, which could impact whitewater trails and other river uses in the area. The Mississippi River at Thebes and Chester shows a slight increase in streamflow, with current levels at 90200.0 cfs and 86600.0 cfs respectively, which is below the normal but should be monitored for any sudden changes that might indicate flooding risks. Water enthusiasts and local communities, particularly around the Cache River, Illinois River at Marseilles, and Big Muddy River, should stay informed of the latest conditions and be prepared for the potential impacts of these streamflow anomalies.