Best way to deal with high water table

[silcozot]

Hi I have been reading TFP for some time and have really learned a bunch! Thanks all.
We are in the process of building our own pool and I have a question about ground water. We are into bed rock about 3 ft and will have some ground water issues. We have 1 main drain 1 skimmer and have put a third line under the main drain in clear stone with a special filter type end 1 1/2" pipe with slits cut in it. Can we run all three return lines to the pump with a valve on the 3rd line we can crack open and suck the ground water from under the main drain and into the pool if we see the liner lifting? Also how would I plumb a line for overfill protection?

in the works....20 x 40 in ground (rock) vinyl liner

 

[duraleigh]

Interesting idea but I can only think of problems trying to dump groundwater back in the pool.

High groundwater should be carried out of the ground away from the pool with a seperate sump pump.

 

[Hotrod30]

Can we run all three return lines to the pump with a valve on the 3rd line we can crack open and suck the ground water from under the main drain and into the pool if we see the liner lifting?

Yes you can..... but I wouldn't.

Two reasons:

One.... You don't know what the ground water contains. That alone would stop me.

Two.... A vinyl liner so I am guessing sand under the bottom and sides. If you should alittle more than "crack" open the valve to the drain under the liner, you could cave-in the sand sides of the hopper (did that in 1992). You want to slowly remove the water from under your liner. Like duraleigh said, a sump pump with the discharge away from the pool is best.


Side note.... in 1992 I had a company replace my liner. They hooked up a trash pump to my under-the-liner drain and started it. Really sucked out the water; and caved in one side of the hopper. What a mess. Now I take care of the ground water with a small pump (30 GPM) and used that to pump from under the liner in the liner replacement of 2004.

 

[reindeerboy]

Our house has the same thing with a vinyl liner. I was told that it used to be a cement pool and they built a vinyl liner over the top of it due to obvious issues here in ND. Now the underground water drains away from the pool and into our drain tile which then goes to our sump pump and then I hooked up a new permanent line this spring that connect to the waste line of our pool filter along with many check valves, and then that goes 60 feet away from the house into our back alley that shoots down the gravel road into the citys sewer.

That is the proper way to get rid of water so you do not have it running back towards the pool, house, or both and it does it at a reasonable rate.

Good luck and be careful, as ground water is a touchy issue like hotrod stated!

 

[silcozot]

Hotrod30

We have no sand in the pool, we started last fall with pounding out the rock and then formed the walls and poured concrete in the hopper and a footing all around to set the walls on. I know some may think this was overkill but thats cause I didn't know how else to do it. Then we put a sand mix concrete on top to make a smooth finish, the liner has been ordered and I hope to get at it next weekend, today more rocks for the retaining wall. Check out my progress so far http://www.flickr.com/photos/silcozot/s ... 597363014/

 

[reindeerboy]

Looks great. We have the same thing on ours. It used to be cement and then here in ND that just doesnt work well at all. They then put a layer of sand over the cement and then layed the liner down. Been there for 5 years now I am told and not real issues with water at all.

Your pool looks awesome! Great pics & Good luck!

 

[Hotrod30]

Yea... I hear what you are saying about ground water and sand and concrete. After rethinking and looking at your pictures, I would still not like using ground water. If you are filling with well water, I guess it is close to the same thing.

About the sand and concrete. On my pool, when the pool company sanded the sides, (all they were doing was to sand the pool and set the liner) they gave the job of mixing the sand with cement to the new guy. Nobody noticed that he was mixing 3 to 1 instead of 6 to 1 (sand to cement) in the mixer. I had 25 bags of cement for 3 projects including the pool on 3 pallets and he went thru 23 bags. He told the pool company owner that "he knew what was needed". Owner didn't even replace the cement either. :x That was in 1982. The hopper and the floor were nice and smooth even thou it was just like cement.

Anyhow, in 1992, when the trash pump (also known as a mudsucker) was hooked up to my under-the-liner drain, one side of the hopper caved down with the rush of water going to the drain. It was repaired, but I still think it is a weak spot. I used and will use a small pump to take care of the ground water when replacing the liner. Works for me; but I don't think I have the trouble with the amount of ground water that you might have.

Anyhow, good luck with your pool.