Washington Well Data › King County
King County, Washington: well depth, water level & drilling cost
✓ 22,932 Ecology records · verified 2026-06-11
How deep are wells in King County, Washington?
The median drilled well depth in King County is 120 ft, based on 13,238 wells with recorded depths in the state Ecology database. Half of all wells fall between 66 ft and 203 ft; 90% are shallower than 310 ft. Wells drilled since 2016 have a median depth of 136 ft.
How much does it cost to drill a well in King County?
Applying published per-foot rates to the local median depth of 136 ft: drilling and casing alone typically runs $3,400–$8,840; a complete system including pump, pressure tank, and hookup typically runs $8,160–$13,600. Actual quotes depend on site access, geology, and casing requirements.
What is the static water level in King County?
The median static water level is 60 ft below ground surface (middle half of wells: 20 ft–125 ft), from 1,006 measurements.
How much water do wells in King County produce?
The median tested yield is 18 gpm (middle half: 10 gpm–33 gpm), from 1,101 pump tests. A typical household needs 5–10 gpm.
Drilled depth distribution
Who drills wells in King County?
Licensed drillers by number of wells completed in this county since 2016, per filed well reports (license roster: Washington Department of Ecology).
| Driller | Wells since 2016 |
|---|---|
| Pierce Kiltoff | 134 |
| Rodney Gilseth JR | 117 |
| Mark Wiese | 114 |
| Daniel Carpenter | 105 |
| Chris Gregory | 70 |
| Michael Cyrier | 69 |
| Justin Bevins | 53 |
| Aaron Ocheltree | 49 |
Get quotes from local drillers
See every recorded well near any address — depths, water levels, yields, original driller's logs — in a one-time report.
Free lookup Property report — $19Method: medians computed from Ecology records (water wells only — soil/environmental borings and decommissions excluded; depths 0–5,000 ft). Cost estimate applies published per-foot ranges (checked 2026-06-11) to the local median depth — full methodology & sources.