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How to Prevent a Floating Vinyl Liner With a High Water Table

  • Step 1: Overdig the deep end of the pool 24"
  • Step 2: Install clear chipped stone ~ 12"
  • Step 3: Mark the deep end hopper depth and run plumbing
  • Step 4: Make the sump basket and connect the plumbing
  • Step 5: Lay down landscape fabric (optional)
  • Step 6: Continue filling the deep end hopper up with stone
  • Step 7: Fill deep end hopper with stone till you are at elevation
  • Step 8: Pour pool bottom

Does your Vinyl Liner look like it has a Big Air Bubble in it? If so, you have a Floating Vinyl Liner

Take a deep breath, this isn’t the end of the world, many inground vinyl liner pools are build with high ground water or a high water table. Provided you make sure that the ground water is dealt with, you shouldn’t have any issues having your inground pool last for years to come.

Do you have clay as your soil base? Do you have a high water table? Do you have water issues?

Water takes the path of least resistance and will essentially find any gap around your pool to fill into. If you have a high water table, high ground water or a soil base that doesn’t allow water to run through it easily, you can get what is called a “floating vinyl liner”. When the ground water pressure is more than the water pressure inside the pool, it essentially pushes the liner off the swimming pool bottom.

There are some different techniques to use depending on if you have an existing inground vinyl liner pool or if you are in the process of building your new vinyl liner pool.

The Traditional Way to Prevent a Floating Vinyl Liner

  1. Dig a 3′ – 4′ deep hole next to the pool
  2. Put a 4″ – 5″ diameter piece of PVC into the hole
  3. Fill the bottom with rock
  4. Put a sump pump into the pit to take out all the water

Existing customers that have this type of sump have come to accept that their liner floats. The problem that generally happens is that the liner has already floated by the time the water gets to the pipe. Re-actively, all you can do is put a sump pump in the pipe to get rid of the water.  What happens if you live in a climate that freezes, now you have a pump and hose that will freeze and crack.

The way to Fix a floating vinyl liner due to high ground water is to be BOTH proactive & reactive.

  1. Proactive – The sump for the pool has to have a catch basin so the ground water can seep into the earth.
  2. Reactive – The system has to have a way to pump the water out when it gets full.

How Build a Sump System for your New Construction Inground Vinyl Liner Pool

Sumps should always be built for vinyl liner pools that have clay soils and for ALL fiberglass swimming pools

  1. Over-dig the pool 2″ – 3″ in the shallow end and transition to the deep end.
  2. Over-dig the deep end hopper 24″ – 36″.
  3. Figure out your final elevations
    1. Bed the entire shallow end & ramp with a chipped clear stone.
    2. Fill the deep end hopper up 75% with stone
  4. Build a rectangle out of 2″ PVC with holes every 2″ – 3″.
  5. Top the rectangle with stone till you get to the elevation you need for you swimming pool bottom.
    1. Make sure there is at least 6″ of stone on top of the PVC rectangle
  6. Run a plumbing line to the equipment slab with a valve on the intake manifold.
    1. When you service your swimming pool you can now move a few valves and drain water out of the sump system.

We have now proactively made a large sump under the inground vinyl liner pool to hold the water and give it a chance to seep into the ground.  The stone on the shallow end and ramp, allows any water to drain to the lowest point. As ground water seeps around your pool it will be diverted to the deep end under you pool. When your swimming pool specialist comes to service you pool, he can drain the water from under the vinyl liner.

Inground Vinyl Liner Sump Pump Process – Prevent a Floating Vinyl Liner

Spray painted line is the elevation for the stone so the pool bottom can get poured to the correct depth.

This tried and proven sump system should be put in every time you have high ground water when digging your pool or if you have clay soils. If your swimming pool builder isn’t putting this in, chances are he isn’t a specialist you want to work with. Don’t let any Bob & Joe build your pool.

How Fix a Floating Vinyl Liner for your Existing Inground Vinyl Liner Pool

Have a floating liner and need it fixed after the fact?  If you have main drains in your pool, there is a way to help your floating liner situation. This solution isn’t ideal, but it gives you a way to handle your high water table and fix a floating liner.

  1. Remove liner
  2. Cut out the deep end hopper or you pool and cut the main drains out.
  3. Dig down 2′ and remove the existing earth.
  4. Fill with stone, PVC rectangle, and attach it to the main drain line.
    1. You loose your main drain, but will have a better change to prevent a floating liner.
  5. Pour pool bottom and hand your new vinyl liner replacement.

If you are worried about not having good circulation, you can install Infusion returns to get better circulation and heated water.

Here is an example of high ground water with clay in Muskego, WI with pure clay. Notice how the ramp also gets washed rock, that way any water that gets to the ramp will drain to the bottom, sump system, where it can be sucked out. To date, this liner has yet to float due to a high water table.