Onslow County, NC Water Table Trend
Is the water table dropping in Onslow County, NC?
Onslow County's long-term well puts the trend at 3.4 ft per decade, declining at a typical pace for a declining county, based on 64 measurements since 1982.
This is one representative well, not a county-wide survey, the same grain limit every page here discloses.
Onslow County's source well, in detail
Depth to water at the last reading was 44.6 ft below land surface. Readings span 1982-08-31 to 2021-07-29, 64 measurements from USGS well USGS-343641077290103 (On-227 Dixon Rs Y25q3 Castle Hayne), part of the National Water Information System. The qualifying bar and the OLS fit behind this trend are documented in the methodology guide.
How Onslow County compares nationally
Onslow County sits at rank 1260th 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. Onslow County, North Carolina is home to about 212,954 people. See the fastest-moving counties guide for how Onslow County stacks up against the most extreme cases nationally.
If you own a well in Onslow County
A dropping water table means a residential pump has to reach deeper and work harder, which shortens its life. In Onslow County, that trend is real, not assumed: 3.4 ft per decade over 39 years.
Depth and quality are separate questions
This page answers a depth question, not a quality one. A well in Onslow 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.