How many GPM should a well produce? The practical answer is enough to meet your household's peak demand. A single number can mislead, because a large family with three bathrooms needs more than a couple in a small house, and storage can stretch a modest yield. This page explains the planning numbers, the logic behind them, and how yield is measured.
How much water does a household use?
The U.S. Geological Survey estimates that each person uses about 80 to 100 gallons of water per day for indoor home uses. USGS: How much water do I use at home each day? For a family of four, that is roughly 200 to 400 gallons a day. Penn State Extension: Water System Planning — Estimating Water Needs [USGS-HOMEUSE source note] [PSU-NEEDS source note]
Why does peak demand matter more than daily use?
Water use bunches into peak periods, typically 30 minutes to 2 hours in the morning or evening. Penn State Extension recommends that a water system supply all of a day's projected use within a 2-hour peak period, so a home using 400 gallons a day should be able to deliver 400 gallons in two hours. Penn State Extension: Water System Planning — Estimating Water Needs [PSU-NEEDS source note]
What is a good well flow rate for a house?
Penn State Extension suggests a minimum flow of 6 GPM from a well for most single-family homes, and scales it by bedrooms and bathrooms: Penn State Extension: Water System Planning — Estimating Water Needs [PSU-NEEDS source note]
| Home | Suggested minimum flow |
|---|---|
| 2 bedrooms, 1 bath | 6 GPM |
| 3 bedrooms, 2 baths | 12 GPM |
| 4 bedrooms, 2 baths | 14 GPM |
| 4 bedrooms, 3 baths | 16 GPM |
| 6 bedrooms, 3 baths | 18 GPM |
These are planning guidelines, not code requirements. Other references set different floors: New Hampshire's water well board suggests a well deliver at least 600 gallons within a two-hour period once a day. NH DES: Determining the Reliable Capacity of a Private Water Supply Well (DWGB-1-13) For existing wells in a home sale, guidance cites HUD's requirement of at least 3 to 5 GPM. Water Systems Council: wellcare Guide to Evaluating Water Wells (for home inspectors) Your lender and local code may set their own minimums. [NH-CAPACITY source note] [WSC-INSPECTOR source note]
What is well yield?
Penn State Extension defines yield as the maximum rate in gallons per minute that a well can be pumped without lowering the water level below the pump intake. A well that cannot meet peak demand is considered low-yielding. Penn State Extension: Using Low-Yielding Wells That definition explains why a bigger pump cannot fix a weak well: the limit is the aquifer, not the motor. [PSU-LOWYIELD source note]
Storage changes the math
Storage lets a modest steady yield meet a high short peak. A pressure tank alone holds little: only about 20 percent of its capacity is usable, so a 42-gallon tank delivers about 8 gallons before the pump restarts. An intermediate storage tank, commonly sized at about 100 gallons per household member, can bridge the gap. Penn State Extension: Using Low-Yielding Wells See low-yield well options for how those systems work. [PSU-LOWYIELD source note]
Work out your own target
You can estimate a target in three steps:
- Daily use. Multiply the number of people by 80 to 100 gallons. Four people: about 320 to 400 gallons a day.
- Peak rate. Divide the daily total by 120 minutes, the two-hour peak window Penn State Extension uses. 400 gallons ÷ 120 minutes ≈ 3.3 GPM sustained over the peak.
- Fixture check. Compare with the planning table above, which also accounts for several fixtures running at once. A 3-bedroom, 2-bath home is listed at 12 GPM.
If your tested yield falls between the two, storage can make up the difference; a household with 4 GPM of steady yield and a storage tank can meet a 12 GPM peak for a limited time. Your installer can size that system; see planning a pump for a new well. If the well falls well short, read low-yield well options.
How yield is measured
A meaningful yield number comes from a pumping test that tracks the static water level, the drawdown during pumping and the recovery afterward. Test lengths vary: Connecticut's code minimum for a new well is four hours, and state and town requirements range from about one to 24 hours. Connecticut DPH: Private Well Guidance for Determining Well Safe Yield (2009) Well pump tests explains what to ask for in the report. [CT-SAFEYIELD source note]
Once you know the tested yield, size the pump to it; see planning a pump for a new well.
Common questions
Is 5 gallons per minute a good well?
It can be, depending on household size and storage. Penn State's planning guidance suggests about 6 GPM as a minimum for most single-family homes, while New Hampshire guidance suggests at least 600 gallons within a two-hour period once a day, which is 5 GPM for two hours. With a storage tank, a lower steady yield can meet peak demand.
What is a low-yield well?
Penn State Extension defines it as a well that cannot meet the peak water demand of the home or farm. It is defined by demand, not by a single GPM figure.
How is well yield measured?
By pumping the well at a measured rate while tracking the water level, then watching how the water level recovers after pumping stops. A short flow test from a faucet shows what the system delivered that day but not how the well recovers.
Does a bigger pump increase well yield?
No. Yield is how much water the well can supply without drawing the water level below the pump intake. A pump larger than the well can supply simply draws the well down faster. The pump should be matched to the tested yield.
What is a good flow rate for a well?
For most homes, a sustained 6 GPM or more meets Penn State Extension's planning minimum, with larger homes planned at 12 to 18 GPM. A well below that can still serve a household with added storage.
Sources & claim context
Citations mark where guidance is grounded. They are general resources dated on retrieval, not guarantees for any property, project, price, licensure, permit or yield. No expert, attorney or reviewer signoff is claimed by this site.
Penn State Extension: Using Low-Yielding Wells · Penn State Extension · accessed 2026-10-10
https://extension.psu.edu/using-low-yielding-wells
Cost figures in the article are Pennsylvania-era estimates; not quotes
Penn State Extension: Water System Planning — Estimating Water Needs · Penn State Extension · accessed 2026-10-10
https://extension.psu.edu/water-system-planning-estimating-water-needs
Planning guideline, not a code requirement; local rules may differ
USGS: How much water do I use at home each day? · USGS · accessed 2026-10-10
https://www.usgs.gov/water-science-school/science/water-qa-how-much-water-do-i-use-home-each-day
Estimate; actual use varies by household
Water Systems Council: wellcare Guide to Evaluating Water Wells (for home inspectors) · Water Systems Council (wellcare) · accessed 2026-10-10
Guideline distances are not legal requirements; check state rules on who may inspect
Connecticut DPH: Private Well Guidance for Determining Well Safe Yield (2009) · Connecticut Department of Public Health · accessed 2026-10-10
Connecticut example; 2009 publication
NH DES: Determining the Reliable Capacity of a Private Water Supply Well (DWGB-1-13) · New Hampshire Department of Environmental Services · accessed 2026-10-10
https://www.des.nh.gov/sites/g/files/ehbemt341/files/documents/2020-01/dwgb-1-13.pdf
New Hampshire fact sheet; not a substitute for a contractor yield test
Claims are grounded in the dated source notes above; project-specific price, yield, licensure and permit answers require site-specific and local verification.