YIELD DETERMINATION FOR VERY LOW YIELD WELLS
How much water do I have?

The lower the yield of your well, the easier it will be to figure that out.

1. Shut off the main valve to the house and the power to the well pump.

2. Connect a hose to the well tank drain. Run water out of the hose until there is no more water coming from the pressure tank.

3. Turn the power to the well pump back on and run water out of the hose until there is no more water in the well. Measure how much water you get using containers of known volume - 55 gallon drum, 30 gallon trash container, 5 gallon bucket, etc.
If you have a jet pump, don't forget to save some water to prime it. This will tell how much water your well holds and you can calculate how high your well fills with this information. Divide the amount of water collected by the amount of water one foot of well bore holds. For instance a 6" well holds about 1.5 gallons per foot. If you collected 50 gallons then there was 33.33 feet of water in the well.

If you can't run the well dry after an hour, turn the hose off and stop worrying because you have more than enough water to run your home with a Well Manager®.

4. Once water ceases coming out of the hose, turn off the power to the well pump and wait for thirty minutes.

5. After waiting 30 minutes, restart the pump and run the hose until water stops flowing again. Measure the water pumped as before. Let's say you ran the hose for five minutes and collected four 5-gallon buckets (20 gallons) of water. That means you have collected the entire yield of your well for 35 minutes (30 minutes you waited and the 5 minutes you pumped). That means your well is producing; 20gal÷35 min= 0.57 gal/min. The daily output that could be obtained from this well is 0.57galx1440min =820.8 gallons.

One note: A pump test of this short a duration will give you an indication of the well's yield but is not necessarily an accurate measurement of the sustainable yield of a well. (Sustainable yield: amount of water in GPM that can be continually pumped from a well without exhausting the aquifer)