Clark County, IL Water Table Trend
Clark County's groundwater trend, from USGS's own readings
Clark County's representative monitoring well shows depth to water rising, getting shallower over time, a fitted trend of 1.7 ft per decade over 18 years of readings.
One well stands in for Clark County's whole aquifer here, the honest simplification every page on this site carries.
What the well actually measured
The most recent reading put water 24.5 ft below land surface. Readings span 2003-01-30 to 2021-02-11, 40 measurements from USGS well USGS-391350087385301 (023-3-12-3760 (Clark Idoa Crn)), part of the National Water Information System. The qualifying bar and the OLS fit behind this trend are documented in the methodology guide.
Where Clark County ranks
Of the 1,449 US counties with a usable trend, Clark County ranks 150th from fastest-rising to fastest-declining, 1 is the fastest-rising water table measured, 1449 the fastest-declining. About 15,076 people live in Clark County, Illinois. See the fastest-moving counties guide for how Clark County stacks up against the most extreme cases nationally.
A dropping table says nothing about water quality
Whether Clark County's water table is rising or falling is independent of what's actually in the water. Depletion can concentrate naturally-occurring minerals, so it's worth checking directly with a water test rather than assuming a depth trend says anything about quality.