Shallow Well Config

[User2342]

Good afternoon,

I purchased a house last year with a shallow well for irrigation that hadn't been used for years. I was able to get the whole system working, but never got great GPM and dealt with cavitation issues.

I'm hoping to do better this summer and think my issue may be how he had the suction side configured. There is no pipe inside the well's PVC casing. Instead, there is a T that runs horizontal to the ground that reduces the pipe from probably 3in to 1 1/2in. There is a check valve right at the T to keep prime.

Would it help if the supply pipe was 1 1/2 all the way down to a foot valve inside the casing?

 

[User2342]

Here is a diagram.

 

[Sponsor]

 

[Reach4]

Cavitation would suggest the pump is too high or the water surface is too low. Keep the suction pipe and any part of the pump no higher than 25 ft above the surface of the water.

Your pump may be sucking too much water. Try lower gpm sprinkler heads.

You might also have a vacuum leak.

 

[User2342]

Thanks for the response. I forget the actual numbers, but water was only 8-12ft down and the well was less than 25ft deep. I checked before replacing the jet pump.

There was a gate valve on the pressure side that I eventually partially closed which stopped the "marbles in the pump" sound so that jives with the lower GPM. From my limited understanding that meant that the pump wasn't getting enough water or that is was air bubbles from somewhere.

A vacuum leak wouldn't surprise me. The plumbing jumped from PVC to metal pipe to irrigation pipe to metal check valve to metal pipe so it clearly was patched over time. The PVC casing could also have a crack underground. I should also mention that the pump inlet was only about 6in from the check valve which I read could cause issues.

It sounds like the lack of a suction pipe going into the well isn't really a concern to you unless there is a crack in the well casing. I am redoing the plumbing from the casing to pump to pressure tank to irrigation system. Hopefully if there was a leak it will have been in there.

 

[Valveman]

The "marble" sound is cavitation that happens when you are letting our more water than the pump can produce or get. That is why partially closing the gate valve stopped the marble sound. It might not make that sound if you valve it back to run at 30-40 PSI.