# Well cleaning



## Adk (Feb 18, 2020)

My drilled well is approximately seventy five years old. It is approximately 60’ deep. In the thirty years I have lived here the well has always provided plenty of water, allowing for multiple uses at the same time without any loss of pressure. Since last summer however, there has been intermittent pressure fluctuation, especially when showering when the washer is on. I have replaced the pressure switch and tank, without any difference in performance. The submersible pump is fairly new and I want to pump the well out to see if silt buildup is the issue. I have seen a couple of YouTube videos describing a system of using compressed air. Has anyone had any experience with this or any other method of cleaning silt out of a well that is too deep to use a standard trash pump?


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## Cabin Fever (May 10, 2002)

The proper term to google is "water well development." There are many ways to develop a well, including bailing, pumping, back washing, surging with compressed air, jetting, and fracturing. Newly drilled wells are always developed by the installer. You could hire a well driller to re-develop your well.


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## jwal10 (Jun 5, 2010)

Sounds like you may have a flow problem somewhere. How old are your pipes? Is the shower tapped in after the washing machine? A shower is fairly low flow, so when the pipe starts to plug up with deposits and when the washer comes on, the flow slows to the shower. Also, have you cleaned the shower head? Remove shower head and turn the valve on, do you have good flow then? Is there a difference in hot and cold flows. Does shower have a combiner valve or 2 separate valves , 1 cold, one hot? Does the shower lose flow when you flush the toilet or open sink faucet?

Just some things to check before spending a lot of money....James


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## Chris in Mich (May 13, 2002)

Not typical to see drilled wells of the vintage you describe; are you in bedrock or till soils? If you have any documentation from when the "newer" submersible was installed, it might provide some detail as to any maintenance that was completed at that time (screen treatment/pump capacity/drawdown rate/etc). Need more detail to provide better guidance but given the depth i might try using a temporary tank/pump to supply pressure down the well to try and liberate any accumulation/debris from the screened interval at approx. 2x your normal operating psi.


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## Adk (Feb 18, 2020)

Chris in Mich said:


> Not typical to see drilled wells of the vintage you describe; are you in bedrock or till soils? If you have any documentation from when the "newer" submersible was installed, it might provide some detail as to any maintenance that was completed at that time (screen treatment/pump capacity/drawdown rate/etc). Need more detail to provide better guidance but given the depth i might try using a temporary tank/pump to supply pressure down the well to try and liberate any accumulation/debris from the screened interval at approx. 2x your normal operating psi.


I replaced the jet pump that existed when I moved in with a submersible about ten years ago. The well is in glacial till. About twenty years ago, my neighbor, with whom I shared the well at the time, pumped sand out of the well when it seemed that we were getting sand in the water on a regular basis. He did it by taking the foot valve off the pipe and adding about six feet of line. Then he unhooked the outfeed line and let it run onto the ground for a few hours. It ruined the impeller but that was easily replaced.


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## Adk (Feb 18, 2020)

jwal10 said:


> Sounds like you may have a flow problem somewhere. How old are your pipes? Is the shower tapped in after the washing machine? A shower is fairly low flow, so when the pipe starts to plug up with deposits and when the washer comes on, the flow slows to the shower. Also, have you cleaned the shower head? Remove shower head and turn the valve on, do you have good flow then? Is there a difference in hot and cold flows. Does shower have a combiner valve or 2 separate valves , 1 cold, one hot? Does the shower lose flow when you flush the toilet or open sink faucet?
> 
> Just some things to check before spending a lot of money....James


All piping, including the well line, was replaced thirty years ago when I bought the place. We’ll line is plastic and everything else is copper. Shower head is new. It does tap in after the washer. No flow problems at any other of the faucets, except for the intermittent problem I described earlier.


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## Adk (Feb 18, 2020)

Cabin Fever said:


> The proper term to google is "water well development." There are many ways to develop a well, including bailing, pumping, back washing, surging with compressed air, jetting, and fracturing. Newly drilled wells are always developed by the installer. You could hire a well driller to re-develop your well.


Th


Cabin Fever said:


> The proper term to google is "water well development." There are many ways to develop a well, including bailing, pumping, back washing, surging with compressed air, jetting, and fracturing. Newly drilled wells are always developed by the installer. You could hire a well driller to re-develop your well.


 Thanks, I did some research using that term and plan to contact some companies to see if they provide development services


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## Chris in Mich (May 13, 2002)

Well development is simply pumping from the well and it seems you have already done so --- sounds to like this pressure issue began in isolation of any other events; yes? Measure your swl with a reel tape that has a 1/2-3/4" pipe end fitting (with drilled center in cap, eye bolt, affixed to tape end) to measure depth of "splash down" to get swl. Monitor as you pump to document drawdown rate. Measure also the depth to the pump and total well depth (if annular space allows). If your drawdown test shows the swl going below the pump you likely have a clogged screen. Lowing the pump level (adding more cable length) may help temporarily, but if clogged the only way to improve recharge rate is to clean screened interval. Pulling the pump would aid in measuring total depth and facilitate sediment removal and improve surge pressures if you decide to go further.


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## Cabin Fever (May 10, 2002)

@Chris in Mich, proper, forceful well development will not only remove sediment from the well casing, but also clean the screen. Not only that, but well development will remove fines from the aquifer that are near the screen. Such a rigorous treatment should provide sediment-free water for a long time.

According to the OP, this well was finished in glacial till. Till is a mixture of sand, silt, clay, and gravel. Consequently, fines are plentiful and sediments blocking the screen and depositing in the well will be an ongoing problem. Around here, wells are generally finished in glacial outwash deposits which are sand and gravel.


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## Chris in Mich (May 13, 2002)

@Cabin Fever; You mentioned bailing as a well development method -- bailing is not going to remove any appreciable amount of consequence -- Well dev with sub-optimal flows can actually cause sediment accumulation in the screened interval. More detail is required to advance a prognosis and a drawdown test is the easiest of these things to benchmark. Also, given the vintage of the well, accumulation of fines is an unlikely cause of an "all-of-a-sudden" flow issue.


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## Cabin Fever (May 10, 2002)

Chris in Mich said:


> @Cabin Fever; You mentioned bailing as a well development method -- bailing is not going to remove any appreciable amount of consequence -- Well dev with sub-optimal flows can actually cause sediment accumulation in the screened interval. More detail is required to advance a prognosis and a drawdown test is the easiest of these things to benchmark. Also, given the vintage of the well, accumulation of fines is an unlikely cause of an "all-of-a-sudden" flow issue.


You're right about bailing. Bailing is just one method of well development and not a godd method for wells set in glacial till. However, bailing is a well development method that can be used in more porous substrate that do not contain significant amounts of fines.

As far as a drawdown test, that would be helpful. If the watertable elevation does not drop below the submersible pump level while the OP has the shower on at the same time he is running the washing machine (or other combination of high water usage), then a plugged screen or sedimentation may not be the culprit for the low water pressure he is experiencing at such times. It could be that the plumbing in his house has scaled significantly, which could also reduce pressure during high water usage events.


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## Chris in Mich (May 13, 2002)

Not to be overly technical, but OP is complaining of low flow, not low pressure -- failure to differentiate the two is a common mistake.


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## Cabin Fever (May 10, 2002)

@Chris in Mich, maybe you missed this.


Adk said:


> Since last summer however, there has been *intermittent pressure fluctuation*, especially when showering when the washer is on. I have replaced the pressure switch and tank, without any difference in performance....


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## Chris in Mich (May 13, 2002)

I'm saying the OP is expressing a decrease in pressure but is more likely describing a reduction in flow. This is the common mistake i'm referring to. End-users almost ALWAYS describe it incorrectly because few know the difference or have the proper appurtenances to adequately quantify.


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## B&L Chicken Ranch and Spa (Jan 4, 2019)

Hi. I have been reading this with a bit of alarm. I would advise you to hire a well driller to look at your well. Messing with the well can cause the well to clog without much recourse other than drilling a new well. As someone else noted, glacier till has a broad mix of particles. If developed improperly you can actually draw fines into the pore spaces the water flows through and clogging them. Well drillers have higher power pumps used for developing wells, they should also have software that will monitor the flow/draw down rates to help with developing. Sometimes you just have to get the experts. Sorry.


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