If your water table is that severe, you will need to set up several well points around the pool perimeter in an effort to "dry up" or at the very least get the water under control prior to excavation.

We have a lot of experience dealing with high water tables. We build gunite pools so our process is different than vinyl construction. We did vinyl for many years, but now only gunite.

The last few projects, we've had to deal with ground water. We excavated just outside a spot at the pool's deep end edge, to a depth below the gravel base. Our gunite pools have usually a 7"-8" floor and 12" of gravel below that. So a finished 8' pool, has a dig depth of close to 10'.

We set a 12" plastic culvert vertically, and drop an automatic sump pump at the bottom. run electric power for a permanent set up. Any ground water will find it's way through the gravel to the bottom of the culvert pipe where the pump can pick it up and discharge.

The discharge may go to a point on the property away from the pool or to another collection point. The pipe has a cap that allows access for servicing of the pump.

Getting a hold on the water during the initial excavation is tricky. With severe water, the walls are constantly caving in. In some cases we have relocated and raised pools in an effort to avoid groundwater or at the very least get an easier handle on it.

Ground water behind a vinyl pool, if really excessive, could have an impact on the structure. Generally, the liners float in high water tables. When the liners float, they usually do not go back wrinkle free. Even when the pool is filled. I have seen this up close.

Clay soil is an expansive type and holds water. Sandy and rocky soil allows water to perk and dissipate.

My suggestion is to find an excavator who has experience with high water tables. Hitting water at 3' is extreme. You will definitely need a permanent pump system in place.

Thank you very much, Mystic Pools. That was super informative! I have heard of the sump pump method too and I think it's something we'll have to plan for. To clarify, our yard seems spotty with water, we hit in some spots and in some not so shallow. Again, really appreciate your comment.

The sump pump is good method. I would suggest having a spare pump on hand for a change out. We set up the plumbing for a quick disconnect for an easy swap.

Yes, groundwater can be spotty. Veins of underground water will go in one direction and never affect an area close by.