Groundwater Data

Click here for a list of groundwater monitoring wells in Mason and Tazewell County with real time water level hydrographs.

Recent Updates

2/9/2026

The 2024 annual report from the Illinois State Water Survey is now available to view. The 2025 report is scheduled to be published in April 2026.

5/12/2025

Monthly precipitation reports for Jan, Feb, and Mar 2025 have been published.

3/24/2025