Low well pressure

[Greenmonster123]

So my brother sent me this video from his nursery. I am 5 hrs from there so details are sparse. He first tried to pressurize the tank but it was fluctuating. He thought the CSV was causing the issue so I told him to take the plug out of the tee before the CSV to see if it would surge to rule out the valve. It still did it with out the valve in the mix so I thought it seemed like it is drawing down. Thoughts?

 

[Reach4]

I suspect the well is running out of water.

Would that because the screen is partially clogged, or the aquifer has dropped? I don't know.

 

[Sponsor]

 

[Boycedrilling]

Yup, looks like the well is drawing down to the pump intake and sucking air. It would help if your brother added to hook up an a ampmeter to the wiring and monitor the amperage. It should fluctuate same as the water fkow.

With this being an irrigation pump. I'm assuming it has sat unused all winter. Does he have a well log for this well?

 

[Greenmonster123]

Yup, looks like the well is drawing down to the pump intake and sucking air. It would help if your brother added to hook up an a monster to the wiring and monitor the amperage. It should fluctuate same as the water fkow.

With this being an irrigation puml. I'm assuming it has sat unused all winter. Does he have a well log for this well?

yeah I told him to put a clamp meter on it to see if amps dropped with water flow, I think he has to go buy one. Right it was turned on for the first time this year today, not sure on the log.

I would be surprised if the water level dropped especially this time of year. The farm is in Maryland on the eastern shore where there is a large aquifer with a high static especially in the spring.

they way they install wells there is with slotted pvc casing with gravel pack. Do these ever fail and allow sediment to block the slits in the casing? Around here the installers use a wound stainless steel screen, not sure if it makes a difference.

 

[Boycedrilling]

Very easily could have mineral build up or biological fouling of the slots. I would pull the pump and video inspect the well.

 

[Boycedrilling]

For high yield wells, I prefer wire wrap stainless steel screens, compared to pvc slotted pipe. Wire wrap screen has 4-5 times as much open area per lineal foot as slotted pipe.

 

[Greenmonster123]

I suspect the well is running out of water.

Would that because the screen is partially clogged, or the aquifer has dropped? I don't know.

For high yield wells, I prefer wire wrap stainless steel screens, compared to pvc slotted pipe. Wire wrap screen has 4-5 times as much open area per lineal foot as slotted pipe.

yes it was a high yield well made over 50 gpm when drilled 3 years ago

 

[Greenmonster123]

Spoke with brother today and have some more info about the well.
50’+/- Deep
30’ screen
20’ case
30-31’ drop pipe.
3hp-35
It was Originally hung on one length of 2” but it drew down to 15 feet so the put another 10’ on it which put it in the screen. Could the pump being in the screen cause it to silt up faster?

 

[Boycedrilling]

Two reasons not to place a submersible pump in the screened interval of a well.

First you create a localized high velocity area thru the screen at the intake of the pump. This can lead to pulling fines thru the screen. It can also cause mineral encrustation of the slots on that area due to the high velocity.

Second, you can lose cooling flow past the motor, because the water is flowing horizontally directly into the intake of the pump and not past the motor.I

I would still pull the pump. Video inspect the well. Plan on redeveloping it. Maybe doing an acid treatment to remove biofouling or mineral encrustation. Different acids for different problems. I use Cetco LBA for biofouling and Cetco DPA for minerals. These are not DIY products or for amateurs to use

 

[Greenmonster123]

Two reasons not to place a submersible pump in the screened interval of a well.

First you create a localized high velocity area thru the screen at the intake of the pump. This can lead to pulling fines thru the screen. It can also cause mineral encrustation of the slots on that area due to the high velocity.

Second, you can lose cooling flow past the motor, because the water is flowing horizontally directly into the intake of the pump and not past the motor.I

I would still pull the pump. Video inspect the well. Plan on redeveloping it. Maybe doing an acid treatment to remove biofouling or mineral encrustation. Different acids for different problems. I use Cetco LBA for biofouling and Cetco DPA for minerals. These are not DIY products or for amateurs to use

I was aware of the cooling issue, I put a shroud on my well that top feds but it is a 6” casing. My brothers is 4” so no room for shroud. Thanks for your help.

 

[Valveman]

I agree it looks like the well screen is clogged.