Bulging pool liner

Hello we have a fibreglass self cleaning compas pool,
We have had a leak which has made a huge bulge running the length of the pool between the fiberglass and the liner,we have had the self cleaner capped and disconnected, but still have the huge lump under the liner, even though there is tombs of pressure from the pool water.i have been told to put a pipe down the vent hole near the skimmer box,which is meant to go directly under the fibreglass. It is hull of water and when I try and siphon the water it gets blocked up with crusher dust,there is definitely water coming out so I think I’m onto something but the problem still not getting solved.can anyone please give me some advice on how to get the water out… sorry about my punturation and spelling thanks 0409101241

It sounds like you're dealing with a challenging issue where water has accumulated between your pool's fiberglass shell and its liner, causing a significant bulge. The presence of crusher dust indicates that the backfill material used around the pool shell may be entering your siphon, complicating the water removal process. Here's a step-by-step approach to address the problem:

1. Continue Siphoning: Keep trying to siphon out the water. If crusher dust is clogging the siphon, you might need a filter or a piece of cloth to cover the siphon's end to prevent blockages.
2. Use a Submersible Pump: If siphoning is ineffective, consider using a submersible pump equipped with a filter to handle the crusher dust. Place the pump's intake near the bulge area to extract the water more efficiently.
3. Drain Inspection: Inspect all drain points and the skimmer box area for any signs of blockage or leakage that might contribute to the problem. Ensure that the vent hole near the skimmer box is clear and properly functioning.
4. Professional Assessment: Given the complexity of the issue, involving a pool repair professional who can assess the situation might be necessary. They can offer solutions, such as injecting grout or another filler to stabilize the area and prevent water ingress.
5. Check for Structural Damage: The bulge indicates that water pressure has compromised the space between the liner and the fiberglass shell. A professional can determine if there's structural damage that needs addressing.
6. Prevent Future Issues: Once resolved, discuss with a professional how to prevent future leaks. This might involve regular inspections, maintenance, or even modifications to the pool's design or drainage system.

It's crucial to address the issue promptly to prevent further damage to your pool's structure and ensure its safe use.

I assume you have unground pool
If you have a bulge in the pool sides or floor it is because the hydrostatic pressure on the outside of your pool is higher than inside the pool.
The backfilling around your pool has liquefied. Specific gravity of water is 1(inside pool), specific gravity of wet(liquefied soil) is 2.5
It is imperative that water is not allowed to accumulate between pool shell and the excavation sides to prevent soil liquefaction.
There should be a 90mm stormwater pipe installed vertically and going all the way to the bottom of the pool, for observation and water pumping.