Next step after the bucket test

lbridges · Mar 29, 2010

There have been a couple of recent posts about pool leaks, I guess as people get ready to start them up again after winter.

And while my current experience is limited to watching a pool build unfold, once upon a time I did some labor type work for a PB in the midwest.

There were a couple of simple tests to help narrow down where to look for trouble. Time consuming, but the price is right. I've not seen the info all in one spot, but if I somehow missed it, my apology and mods please feel free to delete this post. So,...

Back in the day I was instructed that pool leaks came in two varieties: as either structural or plumbing. The ability to tell one from the other is what I hope to accomplish in this post. Of course, first you need to confirm you have a leak, and the bucket test is as good as any I know. OK, so now you know you have a leak.

Turn the equipment off. Fill the pool up to its normal operating level. When the water movement stills, use a pencil to mark the water level on a grout line. After 24 hours with the equipment off use the pencil again to mark the new level. Barring rain or a strange neighbor, this mark will be below the original mark.

Next, carefully fill the pool back up to its original mark. Now, turn on the pump and let it run continuously for 24 hours. Again, mark the level of the water with the pencil.

If the pencil marks with the pump "off" is at the same level as with the pump "on", it means you have a structural leak and should move on to things like dye tests around the light niche (actually anything that penetrates the pool tank/shell), perform an inspection for shell cracks (look closely for grout line problems - missing grout may indicate bond beam cracks), etc.

If the pencil marks with pump "off" and pump "on" are different (higher or lower), it means you have a plumbing leak.

If the water loss is greater when the pump is "on" (the mark is down lower than the pump "off" line), the pressure side is leaking.

However, if the water loss is less when the pump is running (the pencil mark is higher on the grout line than with the pump "off"), it means the suction side is leaking.

OK, that's it, reasonably simple test, cost essentially nothing (time & pump electricity). Hope it helps somebody. And it would be nice if the newer crowd of PBs and techs could confirm/deny if my reasoning is still valid with modern systems. With modern tech, and maybe with a plumbing leak it would be time to call in the electronic leak detection people?

Butterfly · Mar 30, 2010

Thanks, Lee.

I also would like to see the PB's & techs respond to confirm/deny. Their days have probably gotten a little busier than they have been lately :-D
So, it may take a while for a response.

jackj · Mar 31, 2010

I guess I have either a suction-side or a shell issue? I have dirt (sand - I'm in FL) in mine, and it's dropping quickly enough that I don't care (if I don't have to) to do two bucket tests with the pump on and off to determine which is the case. If not needed. I DO know that it leaks with the pump off; just don't know if it's more than with it on or not. I've had a bunch of times of the skimmer leaking, and in fact just patched it up again. But I don't THINK that the dirt could have come from there. Or could it? If so, I could be okay, as I've now patched it.
With the pump off, I checked the skimmer with some food dye, and it went down the drain pretty quickly. I couldn't tell where the leak was, though, as it was past the bottom of the skimmer. It COULD have been just below where the basket ends and the pipe begins. I was able to to pull up a bunch of previous repairs around that area (i.e. old instant weld putty), and I re-sealed it, trying to extend it down into the pipe as far as I could. Could the leak have been there? While there may be more than one leak, could dirt have come in from that location?

lbridges · Mar 31, 2010

jackj,

If you're asking me, I doubt I can help. Back when I did this I was the least talented member of the crew. I was the guy wielding a shovel, and sent out to put the marks on the wall - then the guys who knew what they were doing would come in the for the fix. I moved on to another occupation (US Air Force) before learning much about pools that is all that useful. The crew I worked for would have found a poor repair, and then just dug it up. As a business, fixing it 'all the way' is the better approach than a patch, especially considering revisits/warranty work is a losing proposition.

If nobody answers here you might best be served to start your own thread so your problem doesn't get overlooked.

Bama Rambler · Apr 1, 2010

Jack -- Is your skimmer just buried in dirt or is it encased in concrete? If it's just buried in dirt then a leak at the skimmer could cetainly have drawn in dirt.

jackj · Apr 1, 2010

Thanks for the response. It's in the pool deck, so I guess the latter. But I think it could still be surrounded by dirt, in that the slab is over the top, but I imagine under the slab it's dirt until you get to the pool enclosure? And that the skimmer is outside of the enclosure?
This morning, after 8 hours with the pump off, it's down a little over an inch using the bucket test. So, significant. It's still above the level of the potential skimmer problem, though. I'm tempted to let it drain down to below that level to find out that way. If there is still a leak there, it may be just below the bottom of the skimmer, where the pipe joins it and it's hard to get putty into very well. I'll try again now, though. If it's an underground pipe, I take it there isn't anything I can do? I've had an armadillo under our pool; don't know if it could be that, not that it matters, I guess. Do they have to dig up to get to the problem, or is there some kind of sealant that's put into the pipes?

Bama Rambler · Apr 1, 2010

It's been suggested several times to let the level go down till it stops. If that's not too big a problem for you, that's what I'd suggest you do. If it stops just below the skimmer it won't really tell you if it's the skimmer or the piping but at least you'll have narrowed down where to look.

I don't think the Armadillo caused the problem. It could have but that'd be rare.

The right way to do it is to dig up the pipes and make a proper repair. Let's not dwell on that until you find where the leak is.

jackj · Apr 4, 2010

Thanks, guys. I dodged a bullet this time. After doing the big repairs in the skimmer (old repairs pulling out so re-doing those), and still finding the water down over an inch overnight, the next morning I tried to go into the pipe again, where it adjoins the skimmer basket, where I couldn't see if there was a leak but it's where the other repairs ended, so I hoped. And, it must've been it. All's well now (FOR NOW). As these things just seem to keep coming back. But for now, water level is stable, and I'm slowly getting the sand out of the pool with the vacuum and my cartridge filter catching most each time it cycles through. Just keep cleaning the filter and doing it again. So, it appears the dirt did enter that way (had never happened with my prior skimmer leaks, though). Boy, I REALLY didn't want to have to have the yard dug up! Oh yeah, is that indeed the necessary repair? There isn't something akin to a radiator stop-leak that will find the hole and fix it? I'm guessing that works by being forced out of the radiator at the leak (and combining with air?) And that wouldn't happen the same way with an underground pipe leak.
Thanks again, all!