"Tom J" wrote in message
...
Chas Hurst wrote:
"rb" wrote in message
. ..
At the top of a 40' well, we have a check valve prior to pump.

With the check valve below the pump, can a hand pump be put on and
used with the electrci pump?
Probably, but you will need a check valve between the hand pump and
the user for the electric pump.

In other words, the check valve there now keeps the water from flowing
back into the underground reservoir. When you add the hand pump, you need
to add another check valve in the pipe going to it to prevent the electric
pump from sucking air through the hand pump instead of water from the
ground. Both check valves are to stop back flow.

I'm assuming you want a way to get water when power is out??

Tom J
The hand pump will already have an internal check valve. An addition check
valve will be needed so the hand pump can't draw water from the user of the
electric pump.