On Aug 11, 6:43*pm, SF Man wrote:
On Thu, 11 Aug 2011 12:35:11 -0700, SF Man wrote:
I'm confused. I just ran out of water.

FWIW, I just measured the water flow (manually) at approximately 5 gallons
per minute for approximately three minutes (until the water table ran dry).

Here's what I did (does this look reasonable?):

1. I flipped the 220 volt circuit breaker off for the well pump.
2. I waited a half hour for the water table to recover.
3. I climbed on top of the tank, opened the hatch ... and ...
Note: Yuck. If you drink the water, you don't want to look inside the tank!

4. While I positioned the bucket below the water into the tank ...
5. My teen flipped the circuit breaker back on.
6. I measured 5 gallons in one timed minute
Note: The pump shut off in about 3 minutes due to the water table lowering.

So, I 'think', without a meter, that I have a flow of 5 gallons per minute
but that the well can only supply that for three minutes for a grand total
of 15 gallons for every half hour.

Two questions arise:
Q1: Is there a better DIY way to measure the water flow?

What you did is OK to a point and for a quick approximation.
To get a better measure I'd turn the water on
very low, like .5 GPM and see at what rate it can keep up
without running dry. Slowly increase the flow rate until it
just runs out of water. Tha'ts the well's continuous flow
rate.



Q2: Do these numbers seem in the right ballpark for what you guys
experience?

A reasonable domestic well target is 15 GPM continuous. Just
had one drilled here in NJ, 4" casing, 50ft deep and that's what
it's yielding. That's enough to support doing things like
watering an acre of lawn with just the well and no tank.
Of course you can't get that in all
areas or with any given well depending on it's condition.
Then you have to figure out what you can get and
what you can support with it. You flow rate of about .5GPM is
extremely low.

I take back what I said before about not seeing the need for
such a large tank. I forgot the irrigation need which is clearly
why you need such a large tank. With a 200 head sprinkler
system, I'm kind of amazed this whole thing works. That's
huge, depending of course on the flow rate of the heads. You're
only pumping 720 gallons of water a day. Even if you water
once every 4 days, that only allows for 2900 gallons, or about
15 gallons a head. A typical rotor on a domestic system is
usually putting out 2gpm. You'd go through that water at
the rate of 7 mins per head.

Have you asked neighbors what their situation is? Either the
aquifer at 500 ft is getting depleted or else you have a well
that just has it;s own problems. If the latter, it's time for
new well. IF the former, then unless there is a deeper
acquifer, I guess you're screwed until the drought ends.
BTW, I though CA drought had ended and this year with
all the snow pack there was plenty of water?