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?