I am under construction on a hillside pool with an infinity edge. The shotcrete was placed in May. The infinity side of the pool is fully exposed (above grade). In recent rains it was noticed that the pool retained water for weeks. The retention basin (which retains the water on the spill wall) did not retain water. Today, we attempted to fill the retention side of the pool with a hose and found that it leaks significantly. You can see the water dribbling out of the bottom of the retention basin (which sits about 2 inches above grade. The contactor, when I mentioned that I suspected this issue existed many months ago, said not to worry that shotcrete is not water proof and that the pebble tech creates the water proof shell. After filling the retention basin today, I sent the pool contractor (and the general contractor as they are in charge of the larger remodel) photos and a video showing the water leaking out. Long story short, I know that shotcrete is not waterproof, but it is clearly a whole lot LESS water proof in the case of my retention basin verses the pool basin. Should I be concerned? What would be the proper fix? Adding more shotcrete to the bottom of the retention basin?
Pool under construction leaking
- Thread starter PeteInCA
- Start date
- Jul 21, 2013
- 53,112
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Either a structure is waterproof or it is not waterproof.
A non-waterproof structure being less waterproof is meaningless.
As your builder said it is the plaster that waterproofs a gunite shell.
If you have any significant voids in the shotcrete it should be filled by the builder using hydraulic cement before plastering. The plaster is typically about 3/8" thick and should not be expected to fill any large defects in the shotcrete.
@AQUA~HOLICS may have some thoughts.
Post pics of what the shotcrete looks like in your retention basin.
A non-waterproof structure being less waterproof is meaningless.
As your builder said it is the plaster that waterproofs a gunite shell.
If you have any significant voids in the shotcrete it should be filled by the builder using hydraulic cement before plastering. The plaster is typically about 3/8" thick and should not be expected to fill any large defects in the shotcrete.
@AQUA~HOLICS may have some thoughts.
Post pics of what the shotcrete looks like in your retention basin.
Thanks for your reply. I don't have an image of the basin right now. Here's the outside where you can see the leak. The cardboard you're seeing is part of the construction process here and is intended to dissolve over time and results in the concrete NOT being in contact with the expansive soil. 
- Jul 21, 2013
- 53,112
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
I need to see the surface that the plaster will cover.
The outside can be rough without causing problems.
The outside can be rough without causing problems.
And to be clear I understand your comment that a structure either is or is not waterproof. My point was that the pool retains water for a long time while the retention basin leaks like crazy. So while both structures are likely porous (as is the nature of shotcrete per my understanding), I was concerned (perhaps unwarranted) that the lower basin (which I believe does not have any major voids or defects) does not hold water at all while the pool does hold water for weeks after a storm. Perhaps the experts on this forum will say as the builder did that the pebble tech is the waterproofing and I should not be concerned. Just looking for confirmation or further advice. Thanks.
Yes you should be concerned, From the looks of the second picture the water leaking is not from saturation.
Most common areas for water leaks are from around plumbing lines, ask the PB to target those areas with a sealer.
Most common areas for water leaks are from around plumbing lines, ask the PB to target those areas with a sealer.
