What counts as a good yield
These are rules of thumb, not regulations. What actually matters is whether the well's sustained yield comfortably covers your household's peak demand — several fixtures running at once — without the water level drawing down faster than the aquifer can refill.
Yield and your mortgage
If you're buying or building, yield isn't just a comfort question — it can gate the loan. FHA-backed mortgages generally look for:
- New or proposed wells — about 5 GPM delivered over a continuous four-hour test.
- Existing wells — roughly 3 to 5 GPM over the same continuous four-hour test.
- Shared wells — a per-connection minimum, with the option to meet it through pressurized storage if the well itself yields less.
Exact requirements vary by lender, loan program, and local jurisdiction — treat these as the general shape and confirm the specifics with your lender. The point for a buyer: ask for the well log and the pump-test result before you're deep into a purchase.
How yield is tested
Yield is measured with a pump test when the well is completed — typically around four hours at a target pumping rate. The driller watches two things: how far the static water level draws down under pumping, and how quickly it recovers after the pump shuts off. A well that holds a steady level at a given rate, and recovers fast, has a healthy sustained yield. The result lands on the well log.
What affects yield
- Aquifer transmissivity — how easily water moves through the formation. Coarse sand and gravel transmit water far better than fine silt or tight rock.
- Production-zone thickness — a thick water-bearing layer feeds the well from more of its length than a thin one.
- Well construction — how much open screen or perforation sits across the production zone, and how well the well was developed after drilling.
- The pump — yield is the well's capacity; the pump has to be sized to it. An oversized pump just draws the well down and cycles.
A low-yield well isn't a dealbreaker
Plenty of good Utah homes run on wells under 5 GPM. The fix is storage: the well trickles into a cistern or large pressurized tank around the clock, and the house draws from that storage at full pressure on demand. A 2 GPM well still produces nearly 3,000 gallons a day — far more than a household uses — it just can't deliver it all in one burst. Storage smooths the peaks. It's a common, accepted setup.
Where to find a well's yield
Every Utah well's completion log records its tested yield, depth, casing, and static water level — and those logs are permanent public records. That's the data this site's calculator reads to estimate what nearby wells produce.
Our calculator pulls real driller-submitted logs from wells near any Utah address and estimates the likely depth, cost range, yield, and water quality in about ten seconds.
Run my addressFrequently asked questions
What's a good well yield for a house?
About 5 GPM sustained is the common domestic minimum and the mortgage benchmark. 10–20 GPM is comfortable for a single-family home with light irrigation; 20+ GPM handles heavier use. Below 5 GPM works fine with a storage cistern.
What yield do I need for an FHA or VA loan?
Generally about 5 GPM over a continuous four-hour test for a new or proposed well, and roughly 3–5 GPM for an existing well, with per-connection minimums and a storage alternative for shared wells. Requirements vary by lender and jurisdiction — confirm with yours.
How is yield measured?
With a pump test at well completion — about four hours at a target rate, watching drawdown and recovery. The sustained yield is recorded on the well log.
Is a low-yield well a problem?
Usually not. Pair it with a storage cistern or large pressurized tank: the well fills storage around the clock, and the house draws from storage at full pressure. Even a 2 GPM well produces thousands of gallons a day.
Where do I find a well's yield?
On its completion log, filed with the Utah Division of Water Rights — a permanent public record that also shows depth, casing, and static water level.
About these figures: Yield benchmarks are rules of thumb common in Utah well practice; the mortgage figures reflect general FHA/HUD well guidance, which varies by lender, loan program, and local jurisdiction — confirm specifics with your lender. Pump-test results for any given well are recorded on its completion log with the Utah Division of Water Rights.