Well depths in Gem County, Idaho
4,689 wells are on record with the state in Gem County.Reported depths run from 18 to 5,760 feet, with a median of 85 feet.
Median depth
85 ft
18–5,760 ft across 3,398 records
Median depth to water
23 ft
0–690 ft across 4,341 records
Median yield
30 gpm
0–12,000 gpm across 3,776 records
What a well costs in Gem County
A median-depth well, borehole only
$3,000–$5,100estimate
But depth is what drives the bill, and it varies. Across the range local wells actually hit — 29 to 241 ft — drilling runs $1,000–$14,500. That spread is the risk you are carrying when you make an offer, and it is why one quote is not enough.
- How this was worked out
- Median depth of 85 ft from 3,398 nearby well records, multiplied by a published statewide rate of $35-$60 per foot. Borehole only.
- Not included
- casing, pump and pressure tank, electrical and trenching, permits and site work
Rate from Well and Septic Cost in Rural Idaho (2026) (swagerbuilds.com, retrieved 2026-09-29). A published statewide figure, not a quote from this county — treat it as a starting point for a conversation with a licensed driller, not a price.
A county median will not tell you about your parcel
Groundwater changes over a few hundred feet. The useful number is what the wells nearest your parcel actually did — check the exact spot instead.
Check a Gem County locationFree. No account.
What things cost in Gem County
Gathered from local quotes and published fee schedules on 2026-09-29. Free, because these are county-wide figures — the paid report applies them to the depths actually recorded near your parcel.
| Item | Typical range | Source |
|---|---|---|
| Drilling a domestic wellBorehole only. Casing, pump and pressure tank are usually quoted separately, so treat this as the starting line rather than the finished cost. | $35-$60 per foot | Well and Septic Cost in Rural Idaho (2026) (swagerbuilds.com, retrieved 2026-09-29) |
| Pump, pressure tank and installationComplete well installed, spanning shallow and deep cases. Depth is the biggest driver, which is why the nearby-well range above matters more than any average. | $9k-$25k total | Well and Septic Cost in Rural Idaho (2026) (swagerbuilds.com, retrieved 2026-09-29) |
| Conventional septic system, installedSpans conventional through engineered systems. Which one a site needs is decided by the health district after a site evaluation, and the difference is most of this range. | $8k-$20k total | Well and Septic Cost in Rural Idaho (2026) (swagerbuilds.com, retrieved 2026-09-29) |
What these numbers are based on
Idaho drillers must file a report for every well they complete, and the Idaho Department of Water Resources publishes them. The figures above come from 4,689Gem County records retrieved on 2026-09-29.
Only 3,398 of those 4,689 records report a total depth, so the median is drawn from those. We do not fill the gaps.
Gem County sits 41 of 44 Idaho counties by median well depth — shallower than the middle county, whose median is 188.5 ft. That comparison is a rough orientation, not a prediction: a single county can contain both 40 ft and 600 ft wells.
Records here span 1944 to 2026. Coverage is most complete from July 1987 onward; earlier wells are patchy and some were never reported at all.
How accurately are these wells located?
About 87% of located wells in Gem County were placed from a section description — a 40-acre block or larger — rather than surveyed. For those, the true well could be several hundred feet from where the record puts it. That matters when you are asking what the nearest well did, and it is why our lookup labels every well with how it was located.
Who to talk to in Gem County
Septic systems here are permitted by Southwest District Health (208-455-5300), not by the county. They decide what site evaluation a parcel needs. For water, get written per-foot quotes from at least two licensed Idaho drillers — the depth range above is why a single quote is not enough.
Before you buy
- Look up the specific parcel, not the county.
- Get two or more written per-foot drilling quotes.
- Ask Southwest District Health what septic evaluation is required.
- Have a title company confirm water rights and easements.
- Have boundaries and acreage confirmed by a licensed surveyor.