Hydrostatic Relief Valve

[Denniswiseman]

Does anyone know if it's possible to fit a Hydrostatic Relief Valve to a fibreglass pool without a main drain
I've only seen it mentioned with a main drain

[Larry]

Hi Dennis

As there has not been any response yet, I will try to shed some light on this with my extremely limited experience with fiberglass pools.

I have seen some pools locally without a Hydrostatic Relief Valve but with a standpipe near the pool instead. I have measured the pipe's depth and it goes down below the base of the pool. If the pool needs to be drained, a pump is lowered into the pipe a few days in advance and the groundwater around the pool is pumped out.

It would be a relatively simple thing to install a standpipe. I guess it would take a good fiberglass professional to install a Pressure Relief Valve in an existing pool, but it may just be impossible if the groundwater is constantly running into the pool preventing the resin application.

Larry

[Denniswiseman]

Hi Larry thanks for that

I was hoping there was someone who had done this
I had a horrible experience when draining the pool
I didn't think the groundwater was that high and it lifted up causing no end of problems
When it went back in I constructed a manhole adjacent to be able to pump out the groundwater
This is about level with the bottom of the pool
I'm not sure how much water needs to be under the pool to float it out
The annoying thing is I could have installed a land drain to a ditch before installing the pool

[Larry]

Unfortunately hindsight is always 20/20.

We build concrete pools and when we are contracted from plan we always include base-level drainage around the perimeter of the pool. Not because a concrete pool would ever float, but rather to keep the concrete relatively dry and prevent subsidence due to boggy, muddy ground.

In our market fiberglass and liner pools are few and far between, and because they are all imported they offer little cost advantage over concrete and tile/ mosaic construction.

Larry