Water Issue Under Pool

wouldn't you measure and calculate 24 hour flow rates prior to firing up your shovel?

this is over your head

And then bottle the water and sell it.

Thanks... the only issue is access and getting a hole excavated large enough to the drill sideways under the pool. The pool is surrounded by thick stone (4" to 7") blocks. The deep end does have an area still as soil but only 4' wide. So maybe a angled auger could make it to the bottom corner of the pool? Maybe enough to put a pvc pipe down?

I was wondering if I could feed a pipe down the drainage pipe I have in there and pump up through that?

Yeah you could do that , you just need to calculate what the inflow of water is...I would go with a self-priming trash pump which can be rented locally....

http://powerequipment.honda.com/pumps/models/wt20

The item not represented in Solar Eagles drawing is the hydrostatic relief valve.

By installing one of these ( about $20.00 each USD) excess pressure from water that develops under the pool will be relieved into the pool itself.

A pool is filled with water, water has weight and exerts force, this force will keep the valve closed. When water builds up under the pool, this water also exerts force, when this force is greater than the force of the water in the pool, the valve opens and the force beneath the pool is released until an equilibrium is reached.

Depending on conditions, Water quality, usage, chemical balance etc. the valve should be replaced every five years. If you have to constantly add make up water and can't find the loss, the valves o ring seal may have failed allowing water to drain under the pool.

When the pool is drained, to be cleaned or acid washed a certain amount of water will inflow into the pool from a normally functioning hydrostatic valve.

I repaired many a pool in southern California coastal area and in Santa Cruz county that had hydrostatic valves.

I would be very suspicious of any such scheme. It introduces water into the pool from an unknown source, which might be contaminated in various ways.

This, " scheme " as you put it is used world wide. And has been used for more than 30 years.

It was engineers, like yourself that developed this product.

Any contaminates introduced will be absolved by chemical titrations of the water itself, that including an adequate filtration system.

hi Tony, thanks for your reply. I have put in a "grease plate" which I was originally advised to do which is meant to act in the same way, however I am suspicious that it'll save the pool as it's literally a plastic bucket with a lid and with no rubber O ring... apparently you just grease it up and place it on, hoping the water pressure will equalise. I will look into the more advanced hydrostatic valve as you suggest. This seems like a good way to go if I can't get a pump or bore a horizontal relief.

to answer another question: no I didn't hit a pipe. There is a lot of streams in the area and even the road had water weeping up through it recently leaving it wet.

I can get a pump into the hole in the pool ( the grease plate bucket) and pump out and get the pool dry if I leave it on 24/7... which is not ideal but I am still trying to build.

I measure the flow of the underground water and it's 1.5 litres per minute.

1.5 liters per min is very small....Here's a 65 gph $14.

https://www.thepondoutlet.com/pondmaster-mini-pumps-and-fountain-pumps

tcmtech is right. A sump that allows enough water to be pumped simply is the way to go. Sucking small amounts of water will be a problem.

It sounds like your land is on a hill.

Is there any possibility that you can trace the flow back to some point outside (uphill?) of the pool area and divert it there.

Just curious, but could you have nicked a water pipe while digging the pool ?

Go for this:

Hydraulic Water-Stop Cement

QUIKRETE® Hydraulic Water-Stop Cement (no. 1126) is a rapid setting, high strength repair material designed to plug leaks instantly in concrete and masonry. Sets in 3-5 minutes and can be used above and below grade.
Designed to block running water or leaks in cracked masonry or concrete surfaces.

Available in:
10 lb. pails
20 lb. pails
50 lb. pails

Use For:

• Swimming pools
• Foundations
• Sealing around concrete pipe

Why not let gravity work for you? Sort of like SE's layout, but can you place a pipe, always downhill, in a ditch until it comes out from under the hill? Then no sump pump is needed, and pressure will not build under the pool. Another thought: Is there any way to measure the pressure of that water flow? If low, maybe the flow would "go away" by the damming of the flow by the construction above.

You could, if you have access to the creek that is lower down (and I suspect you do, or would not have mentioned), you can build a sluice box in the stream that results in an increased velocity through the box (this will reduce pressure to below ambient pressure on any side arm to the sluice box), thus you can literally suck the water out from under the pool easily, no powered pump required.

Have fun. I suppose if you were extremely creative, you would find a way for small flow to travel uphill, be filtered, and supply the pool?

I had the same issue while building our concrete pool at home. We live in an island and the underground water level is at 5 Ft below surface (1.5 meters). The soil is composed by a sandy mud, which crumbled during the excavation due to the underground water pressure. THis problem drove me mad enough to consider abandoning the idea of building the pool. We finally solved the problem using a couple of submersible pumps and by applying Hydraulic Cement to the (mud) walls of the trench immediately before pouring the concrete. It worked, having had no problems at all for the last 10 years. We even had to leave the pool empty for a week or so while doing repairs on the skimmer having also had no problems.

Run a hose or pipe or whatever you have and then take your Shopvac to the low end and start the water flowing with the vacuum cleaner.