Multnomah County, OR Water Table Trend
Is the water table dropping in Multnomah County, OR?
Multnomah County's long-term well puts the trend at 0.3 ft per decade, holding roughly steady, based on 148 measurements since 1937.
One well stands in for Multnomah 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 32.7 ft below land surface. Readings span 1937-10-19 to 2026-09-09, 148 measurements from USGS well USGS-452725122354301 (01s/02e-29bca2), part of the National Water Information System. The qualifying bar and the OLS fit behind this trend are documented in the methodology guide.
Where Multnomah County ranks
Of the 1,449 US counties with a usable trend, Multnomah County ranks 454th from fastest-rising to fastest-declining, 1 is the fastest-rising water table measured, 1449 the fastest-declining. About 795,897 people live in Multnomah County, Oregon. See the fastest-moving counties guide for how Multnomah County stacks up against the most extreme cases nationally.
A dropping table says nothing about water quality
Whether Multnomah 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.