Cass County, IL Water Table Trend
Cass County, IL: the closest actual trend
Scott County, IL, 26 miles from Cass County, is the closest county with a qualifying well, and its water table is declining, slower than most declining counties.
No well inside Cass County clears this site's 15-year qualifying bar, so this is the closest real reading, not a measurement of Cass County's own aquifer. Worth checking your own well's depth log against it rather than assuming it matches. See Scott County, IL's full page. See the no-data guide for why a county this close to a qualifying well still doesn't get its own number.
About Cass County
Cass County, Illinois covers 376 square miles and is home to about 12,713 people. USGS's National Groundwater Monitoring Network covers 1,449 of 3,222 US counties (45%) today; Cass County isn't one of them yet, see the methodology guide for the exact qualifying bar.