Union County, NJ Water Table Trend
Union County, NJ: what the water table is actually doing
Union County's representative monitoring well shows depth to water holding roughly steady, a fitted trend of 0.2 ft per decade over 83 years of readings.
This is one representative well, not a county-wide survey, the same grain limit every page here discloses.
Union County's source well, in detail
Depth to water at the last reading was 7.1 ft below land surface. Readings span 1943-06-30 to 2026-09-16, 656 measurements from USGS well USGS-404106074171901 (390119-- Union County Park Obs), part of the National Water Information System. The qualifying bar and the OLS fit behind this trend are documented in the methodology guide.
How Union County compares nationally
Union County sits at rank 478th of 1,449 ranked counties, ordered rising-to-declining, so a low number means a rising water table and a high one means fast decline. Union County, New Jersey is home to about 594,160 people. See the fastest-moving counties guide for how Union County stacks up against the most extreme cases nationally.
Depth and quality are separate questions
This page answers a depth question, not a quality one. A well in Union County can be stable in depth and still worth testing for quality, or declining and still test clean, the two are measured separately, and only a direct test settles the second one.