Major Blowout - What happened?

[jerald]

So I went to add a little chlorine to my pool this morning before work and found this:



The water was gone. The liner was split vertically. The outer "shell" was buckled and tore up. At least 4 of the posts for the deck buckled.

What in the world happened?

I'll investigate more tonight, but all I can figure now is that the liner split suddenly and the rush of water pressure buckled the other wall and the posts, pulling down some of the deck. The liner was split right at the filter return, but I would have guessed that if it started to leak it would just "leak", not start a flash flood.

We bought the house 2 years ago and I got the contact info for the guy who installed the liner (recently is what we were told) and plan to contact him. I plan to repair it but I'd love to know what caused it so I can make sure to prevent it from happening again.



This is a 24' x approximately 52" round above ground pool. The deck is older, maybe 15-20 years but was very solid.

 

[Texas Splash]

Wow! I'm am sorry to see you going through that. Aside from the possible liner rupture, perhaps a soft spot underneath? Collapsed a bit and lost its stability perhaps? I'd be curious to hear what your contractor says he evaluates the situation. My goodness. I hope everything goes as well as can be expected for you. Keep us posted.

 

[TonyJr]

Wow that is not good! However it os repairable. I agree that it could have been a soft spot putting undue stress on the liner. Other causes could be manufacturing defects (rare), delamination of a seam, some kind of spikey animal piercing near the bottom? Potential sabotage?! Maybe not so much sabotage but I hope you can get it fixed and back in use soon.

 

[phonedave]

Was your return leaking?

My brother had the same thing happen to his pool. He had a slow leak around his return that he ignored. The slow dribble of water down the outside of the pool caused the wall to start to rust at the return. Once you have an interruption in the smooth circle of the return cut out, you now have a stress riser (kind of like how if you have a torn meniscus in your knee, they actually fix it by cutting the end of the tear into an arc so it does not tear more).

Once you have that stress riser, it's only a matter of time until that wall opens like a zipper. When it does, the force of all that water running out is going to easily blow out the sections next to it. My brothers 16' AGP blew out in just the same way, with 3 kids in it at the time. Nobody was hurt, but it washed a couple of yards of freshly placed topsoil down his neighbors driveway into the street.

 

[zea3]

I can't tell by the picture, but a line of rust at the return is the most likely culprit. My sister's pool did the same thing. Had a minor leak at the return and never repaired it. They could see a small line of rust but thought it was surface only. Nope. Pool split on the rust line after the pool became over full in a heavy rain, as clean as perforated paper!

 

[pabadear]

Ugh, what a bad way to start off your morning. I moved into my current house last year and it contained an above-ground pool..Two days into the house I noticed some algae so as i was brushing it off, the liner just tore about 4 inches instantly and it was game over after that. 8300 gallons gushed out which spread the cut to about 4 feet across and the pool was empty in a matter of seconds. That liner was also recently installed according to the previous owners - 3 years to be exact. After getting several people to look at it, they concluded that it happened due to pool water chemistry, which deteriorated the liner over time and it was just a matter of time before it popped so thankfully it happened without anyone being in it.

Did you notice any noise during the night? When my pool emptied out, it sounded like a very powerful water fall for those few seconds. Perhaps that can tell you if it was a big leak that emptied out the pool over time during the night or if it was sudden like mine. Based on the amount of damage though, it looks like it was sudden and the water exited rather quickly.

 

[jerald]

Ugh, what a bad way to start off your morning. I moved into my current house last year and it contained an above-ground pool..Two days into the house I noticed some algae so as i was brushing it off, the liner just tore about 4 inches instantly and it was game over after that. 8300 gallons gushed out which spread the cut to about 4 feet across and the pool was empty in a matter of seconds. That liner was also recently installed according to the previous owners - 3 years to be exact. After getting several people to look at it, they concluded that it happened due to pool water chemistry, which deteriorated the liner over time and it was just a matter of time before it popped so thankfully it happened without anyone being in it.

Did you notice any noise during the night? When my pool emptied out, it sounded like a very powerful water fall for those few seconds. Perhaps that can tell you if it was a big leak that emptied out the pool over time during the night or if it was sudden like mine. Based on the amount of damage though, it looks like it was sudden and the water exited rather quickly.

We didn't hear anything, but from the evidence around it, it would have been a flood to see. Stones washed out under the heater and filter, and a trail of sand and stuff it carried with it. Since it happened, I sort of wish I could have at least enjoyed watching it go. =) About 16,000 gallons give or take.

2 days in? That would have been frustrating.

 

[jerald]

Was your return leaking?

My brother had the same thing happen to his pool. He had a slow leak around his return that he ignored. The slow dribble of water down the outside of the pool caused the wall to start to rust at the return. Once you have an interruption in the smooth circle of the return cut out, you now have a stress riser (kind of like how if you have a torn meniscus in your knee, they actually fix it by cutting the end of the tear into an arc so it does not tear more).

Once you have that stress riser, it's only a matter of time until that wall opens like a zipper. When it does, the force of all that water running out is going to easily blow out the sections next to it. My brothers 16' AGP blew out in just the same way, with 3 kids in it at the time. Nobody was hurt, but it washed a couple of yards of freshly placed topsoil down his neighbors driveway into the street.

I think you nailed it. I investigated more last evening and there was corrosion around the return that I couldn't see before (under the plastic connector). There was evidence of a slow leak that I could see but it didn't register as an issue. I never saw water or drops running down, but you can see water spotting/deposits or something in this picture. That pool wall is original, so roughly 20 years old. Probably has been slowly corroding over time and maybe when the pump kicked on last night the pressure was the final straw and the metal gave out. Other than the corrosion right around the return, it was a clean tear all the way up and down the wall.




Once the wall gave away, I believe the liner ballooned out and pushed out on the posts (buckling them) while pulling down the deck until the liner split open, spilling the water and relieving the pressure.