Well Water Flow/Capacity Test

I have a client looking for a well water capacity test. I have a flow rate meter that I can put on an outdoor faucet and measure PSI and GPM. How long should I run the water for a “good” test?

Here’s a good reference William;



…general information or a Well Certification??

General Info

Try this its what i do and its never failed. it is accepted by FHA.

which model do you have?

Measureman Water Pressure and Flow Test Gauge Assembly – Measureman Direct

Sounds like they want to have a well yield test done. Make sure you understand the difference.

1 Like

I do flow tests all the time including yesterday. A typical flow test is 2 hours. Make sure that you explain in your report on flow that:
This test measures relative (functional) flow rate over time. The flow rate is based on piping, hose diameter, etc. This test does not uncap the well or examine the pump or system. This test does not measure well capacity, recharge rate, depth of well water, static water level, or draw down rate and level.
The flow rate should remain relatively stable and the well should be able to maintain this over the duration of the test.
Try to connect to the highest supply source to be fair. If there is a stand-pipe near the well head, those tend to be high flow. Though you have a flow meter (I do too), you still have to constantly monitor it in case the well runs out of water. A pump can get damaged running dry. And a flow meter does not replace testing flow adequacy with multiple fixtures open. Yesterday, with two showers going, I had a dribble at both, even though flow at my meter was technically adequate. BTW, I check all the baths, kitchen, etc., before starting the flow test.
Done simultaneously with an inspection, they are easy extra money, unless you find a problem well or pump, then the poop can hit the fan! Try to ask the seller or seller’s agent if there are any known problems with the well before starting the test. I’ve had a couple of sellers go crazy ballistic when I find that their well can’t deliver water for two hours. “I’ve lived here twenty years. Raised four kids and we never had a problem with our well until you showed up!”
Wells are really expensive and important, so be careful, competent, and confident when checking them. (That applies to everything we do, now that I think of it)