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We've had unusually dry weather and our well has run so low that we had to call in a water hauling company to refill it a few days ago.

The water man told me that even though he dumped in ~ 1000 gallons, a great part of it will seep out of the well to the surrounding (drier) aquifer, the same way groundwater makes its way inside the well in normal conditions. Now a few days later, the water is low again.

I'm thinking some kind of drinking-water-safe plastic poly sheet sown or welded together at the seam would create a long and flexible tubing that could be progressively immersed inside of the well (with weight at the end) to effectively waterproof it on the inside.

The well could then be refilled to the top and hold all the water that it's containing, instead of slowly seeping it out. Under normal conditions, the sleeve can be removed.

The well is 2 feet wide, 15 feet deep. 2 ft diameter, 3 ft long concrete pipe sections stacked on top of each other.

There's also another well on the site (very low water as well) that's 4 feet wide, 15 feet deep - a much better candidate for the concept as it could hold twice as much water.

Does this sound doable? What are the problems I might face?

706Astor
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cannotcompute
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2 Answers2

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Well liners are generally made to order. One of your issues will be to find a company that can make what you want.

You will need to ensure the liner is the correct size and that it does not tear when inserted into the well, while being filled with water, or when it is being removed from the well.

You mention your wells are cased with concrete pipes. They will mostly be smooth on the inside of the well. However, there may be rough spots or chunks of concrete missing, or the joints may be rough and have sharp edges.

Every insertion and removal of the liner risks tearing or weakening the liner.

Another option, if the have the space, is to place a water tank on the surface and re-plumb the downpipes from all the roofs to discharge rain water (when it falls) into the tank. During droughts the tank can be fill by water brought in by a tanker.

Fred
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I see two ways:

  1. I've had great experience in my pressure vessel design with a 2.3 mm thick liner of polypropylene or polyethylene. In a pinch, you can weld PVC, but I don't recommend it. Thinner stuff works as well, but the 2.3 mm allows you to place a weld bead on the edge using standard weld rod and plastic welding tools.

  2. If not, for a pretty reasonable DIY project, you can always coat the inside with resin, with a bit of fiberglass. (3 oz / sq ft of glass reinforcement should line it perfectly.) In terms of difficulty, think of putting 3 coats of wall paper on the inside of this well In the USA, drinking water approved containment services should be NSF listed. A great resin for coating the inside of the tank would be Reichold Dion 9102-00 Impact. It's NSF approved for coating any storage container or piping system.

By the way, all vinyl esters usually have BPA, if you're worried about that. Fortunately, they make FDA approved polyesters, which do not have BPA, but those aren't NSF approved.

Mark
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