Jefferson County, IA Water Table Trend
Is the water table dropping in Jefferson County, IA?
Jefferson County's long-term well puts the trend at 1.9 ft per decade, declining at a typical pace for a declining county, based on 94 measurements since 2008.
One well stands in for Jefferson 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 15 ft below land surface. Readings span 2008-12-02 to 2026-10-20, 94 measurements from USGS well USGS-405451091483301 (071n08w32bbd 2008iacrn-9), part of the National Water Information System. The qualifying bar and the OLS fit behind this trend are documented in the methodology guide.
Where Jefferson County ranks
Of the 1,449 US counties with a usable trend, Jefferson County ranks 1166th from fastest-rising to fastest-declining, 1 is the fastest-rising water table measured, 1449 the fastest-declining. About 15,781 people live in Jefferson County, Iowa. See the fastest-moving counties guide for how Jefferson County stacks up against the most extreme cases nationally.
What a declining table means for a well pump
Because Jefferson County's water table is actually declining, not just a general worry, a well owner here should consider comparing home-warranty plans that cover well-pump failure before one happens.
A dropping table says nothing about water quality
Whether Jefferson 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.