Thoughts on how to calcium leaching - Leakage behind tile in grout line

bobandsherry

Bronze Supporter
Apr 20, 2016
370
Riverview, FL
#21
You’d have to pull up the pavers to see the condition of the base.

Or a leak detection company with very specialized sounding/infrared equipment.
I was thinking, if there was a leak at the descents then I should see a drop in my water level. Minimal rains this past winter and water level hasn't dropped. I've run the descents minimally but will open them up and run them full throttle for the week. my pH will rise up even more than usual, but that should give me an indication if there's a leak from them. Thanks
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,513
Tucson, AZ
#22
So here's my opinion based on those build photos - you do not have a leak. What the builder did was create a "bathtub" between the retaining wall and pool wall and, over time, the soil trapped between them is essentially holding water. That moist soil is keeping the pool wall "wet" and the water is eventually migrating out towards the pool. There's probably areas of that pool wall where the tile is that are not well sealed and so the water is simply finding the areas of the tile that are easiest to escape from. What the builder should have done was to install a surface drain on that raised wall and pitched the pavers so that the flow of any water on the surface there goes towards the drain. They should have also buried some 4" perforated drain pipe on either side of that area about 2-3 feet below the surface and then create an exit in the retaining wall for it. That would then move an excess water built up in the soil there away from the pool wall.

My guess is that none of that was done and now you're simply seeing the results of slow hydrostatic leakage. You could remediate the area with a drainage installation but that's going to cost you quite a few Benjamins to accomplish....a pumice block will cost you $5 and little bit of elbow grease will solve the efflorescence while you save up for the drainage overhaul.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,513
Tucson, AZ
#25
But, where is the water coming from?
+1 to what Matt wrote -- and glad he posted before me so I didn't have to type all that.:laughblue::laughblue:

Water is probably draining down thru/around the pavers.
Yeah, it's Florida....sourcing water its not an issue :laughblue:

The reason why I think the way I do is that I have an area of my pool where the pool wall and property line wall are about 3-4ft apart (it's probably 5 ft if measured accurately as that would be code). That area of the ground, in the winter, always looks sopping wet and never really dries out. It's also shaded quite a bit due to the low sun exposure. Because of this, you'd swear I have a leak there, but I don't. Then, when the summer comes and the sun is a bit higher, the surface dries out.

It's all just retained water and it shows up even here in the desert because of the heavy clay soil, some drip irrigation there and the low sun exposure in the winter. I dod a test dig and, sure enough, the soil is saturated down at least 18". I wouldn't do any drainage there simply because the clay will hold the water more tightly than a drain pipe could pull it away unless I dug out that entire area and replaced the clay with sandy soil, DG and crushed stone. Really not worth the effort at all.

So, in my opinion, that area is just building up water over time and staying wet because there's no where for the water to go. It's entirely possible that the sheer could have a tiny leak too, but I bet it's more just from rain exposure and wet kids and people jumping in and out of the pool there.
 
Likes: bobandsherry

JamesW

TFP Expert
Mar 2, 2011
12,837
#26
It might not be a leak, but I suspect that it might be.

Water should be able to go straight down to drain away.

Maybe run the sheers for a while and then see if the grout feels wet.

If you could drill a tiny drain hole through the grout, that might help identify the problem.
 

bobandsherry

Bronze Supporter
Apr 20, 2016
370
Riverview, FL
#27
So here's my opinion based on those build photos - you do not have a leak. What the builder did was create a "bathtub" between the retaining wall and pool wall and, over time, the soil trapped between them is essentially holding water. That moist soil is keeping the pool wall "wet" and the water is eventually migrating out towards the pool. There's probably areas of that pool wall where the tile is that are not well sealed and so the water is simply finding the areas of the tile that are easiest to escape from. What the builder should have done was to install a surface drain on that raised wall and pitched the pavers so that the flow of any water on the surface there goes towards the drain. They should have also buried some 4" perforated drain pipe on either side of that area about 2-3 feet below the surface and then create an exit in the retaining wall for it. That would then move an excess water built up in the soil there away from the pool wall.

My guess is that none of that was done and now you're simply seeing the results of slow hydrostatic leakage. You could remediate the area with a drainage installation but that's going to cost you quite a few Benjamins to accomplish....a pumice block will cost you $5 and little bit of elbow grease will solve the efflorescence while you save up for the drainage overhaul.
Now this is what I was thinking, but didn't want to sway the discussion. In theory the water should run off the pavers as they are pitched towards the screen, away from the pool, so most water should run off and what doesn't should be able to seep deep into the soil. But Florida can have some heavy periods of rain could be this causes more to run between the pavers and fill the tub. It may also explain why that area needed the pavers cleaned to remove mold/mildew that was appearing in the sand between the pavers. Agree with you on the pumice stone approach, that's what I've been doing but def seems like this shouldn't be an ongoing required maintenance. I will reach out to the PB and see what he has to say, but where do you think that will end up going? :(

Thanks
 

bobandsherry

Bronze Supporter
Apr 20, 2016
370
Riverview, FL
#28
Yeah, it's Florida....sourcing water its not an issue :laughblue:

The reason why I think the way I do is that I have an area of my pool where the pool wall and property line wall are about 3-4ft apart (it's probably 5 ft if measured accurately as that would be code). That area of the ground, in the winter, always looks sopping wet and never really dries out. It's also shaded quite a bit due to the low sun exposure. Because of this, you'd swear I have a leak there, but I don't. Then, when the summer comes and the sun is a bit higher, the surface dries out.

It's all just retained water and it shows up even here in the desert because of the heavy clay soil, some drip irrigation there and the low sun exposure in the winter. I dod a test dig and, sure enough, the soil is saturated down at least 18". I wouldn't do any drainage there simply because the clay will hold the water more tightly than a drain pipe could pull it away unless I dug out that entire area and replaced the clay with sandy soil, DG and crushed stone. Really not worth the effort at all.

So, in my opinion, that area is just building up water over time and staying wet because there's no where for the water to go. It's entirely possible that the sheer could have a tiny leak too, but I bet it's more just from rain exposure and wet kids and people jumping in and out of the pool there.
What do you think about putting a weep hole or two in the outside wall using a long masonry bit? I've attached a picture of that area after the pool was completed. There's about 18" of wall, figuring making a path of lessor resistance. Thoughts? Photo in Pool Construction   Google Photos.png
 
Likes: JoyfulNoise

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
3,269
Northern NJ
#29
What do you think about putting a weep hole or two in the outside wall using a long masonry bit? I've attached a picture of that area after the pool was completed. There's about 18" of wall, figuring making a path of lessor resistance. Thoughts? View attachment 93205
Water flows where it wants to flow unless you accumulate it and direct it with drains. No guarantee that the water will find the holes you drilled.
 
Likes: bobandsherry

JamesW

TFP Expert
Mar 2, 2011
12,837
#31
Maybe you could insert a soil moisture sensor into the ground through a hole in the deck or from the back to monitor soil moisture content over time to see how it changes.
 
Likes: bobandsherry

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,513
Tucson, AZ
#32
Maybe you could insert a soil moisture sensor into the ground through a hole in the deck or from the back to monitor soil moisture content over time to see how it changes.
Just a note from someone that’s tried this in a gardening context, most of the cheapo (under $30) moisture probes one finds at their local gardening supplier or online are NOT designed for continuos monitoring nor do they give you a quantative readout. Most are simple galvanic couples that deflect a galvanometer needle on a scale of 0 to 10. Some of the better ones have a screw adjustment that lets you set the upper bound of what you consider to be “soggy wet”. If you leave the probe in place, one of the electrodes will corrode away completely.

Not a bad idea though if you can find a way to do it without too much destruction of the existing hardscape.
 
Likes: bobandsherry

JamesW

TFP Expert
Mar 2, 2011
12,837
#33
If the pavers are loose set, you should be able to remove one near the efflorescence and dig down behind the wall to the depth of the tile.

Then, turn on the sheers and see if water shows up.
 

bobandsherry

Bronze Supporter
Apr 20, 2016
370
Riverview, FL
#34
If the pavers are loose set, you should be able to remove one near the efflorescence and dig down behind the wall to the depth of the tile.

Then, turn on the sheers and see if water shows up.
They are no longer set loose. They have had "Seal and Lock" applied and joints now pretty hard and tight. I had waited a year to have them sealed, just in case something went wrong. May still be areas with small hole in corner of pavers that I can push through for moisture reading, as you had suggested earlier. Looking on Amazon for what's the right tool for the job.