Where did my water go...leak?

joseywales

LifeTime Supporter
Jun 11, 2009
250
Exton, PA
#1
I drain below the skimmer each year.

7 years, never had an issue. Looking at my pool though, the water level seems really low. It's the original liner. Can a leak develop in the off season? Maybe it was a really slow leak during the summer and with no refills, etc., it's now shown itself. Pool had floats in it and was covered.

How can I determine if there's a leak BEFORE refilling the pool?

I can search the area at and just above the current water level, figuring the draining would have stopped at the level of the hole

Where are the most likely spots that a leak would have developed in the off season?

Maybe add a few inches and see what happens?
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
10,927
Houston, Texas
#2
It is possible for leaks to develop at any time, however we need to answer some questions to see if you have a leak or not. Did you cover the pool, and if you did, did you use a cover pump to pump water off the cover at any time? Does your pool have a main drain? Did your pool freeze solid at any time over the winter? If the pool was uncovered was there a lot of windy days over the winter?

Instead of adding a few inches I would run a bucket test first. Take a bucket and partially fill it with pool water and mark the water line on the inside of the bucket with a sharpie. Set the bucket on a step inside the pool so it is partially submerged and mark the water line on the outside of the bucket. Let the bucket sit undisturbed for 24 hours and mark both water lines again. Measure the distance between the inside water lines and the outside water lines. If they measure about the same there is no leak. If the water loss is greater outside the bucket than inside you have a leak somewhere in the pool.
 

joseywales

LifeTime Supporter
Jun 11, 2009
250
Exton, PA
#3
It is possible for leaks to develop at any time, however we need to answer some questions to see if you have a leak or not. Did you cover the pool, and if you did, did you use a cover pump to pump water off the cover at any time? Yes. Covered for the entire off season, with floats and clips to keep the cover tight-ish. I did not pump any water off the cover Does your pool have a main drain? It's above ground, so I do not have a main drain. Did your pool freeze solid at any time over the winter? That's possible, but I can't say for sure. My guess is yes though. If the pool was uncovered was there a lot of windy days over the winter? Funny, because I had answered a lot of these questions in my original draft, but it seemed too long. Although it was covered, we do get heavy winds throughout the season and in fact, it's windy as heck right now!

Instead of adding a few inches I would run a bucket test first. Take a bucket and partially fill it with pool water and mark the water line on the inside of the bucket with a sharpie. Set the bucket on a step inside the pool so it is partially submerged and mark the water line on the outside of the bucket. Let the bucket sit undisturbed for 24 hours and mark both water lines again. Measure the distance between the inside water lines and the outside water lines. If they measure about the same there is no leak. If the water loss is greater outside the bucket than inside you have a leak somewhere in the pool.
See my comments in red above- hopefully that font worked, otherwise I will edit it.

I'll have to ponder a bucket test, as I don't currently have the steps in the pool. Also, there's still some snow melting in there. 70 this weekend should take care of that!
 

joseywales

LifeTime Supporter
Jun 11, 2009
250
Exton, PA
#4
I should also add that the cover seems to have taken a beating this year. It was in very good+shape, but it will need to be replaced this year, so winds have been wicked this off season.
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
10,927
Houston, Texas
#5
Some folks with AGPs have a main drain, so I always ask when troubleshooting leaks. You could wait until the steps go back in and try the bucket test then, if you want. You could also mark the water level inside the pool with painter's tape, and check the level again in a few days. Strong wind will lead to some evaporation but if it is over an inch you may want to start looking for leaks in the liner. Sometimes when pools freeze solid little tears develop in the liner. Liner age combined with cold weather make the vinyl more brittle and prone to break.
 

joseywales

LifeTime Supporter
Jun 11, 2009
250
Exton, PA
#6
Some folks with AGPs have a main drain, so I always ask when troubleshooting leaks. You could wait until the steps go back in and try the bucket test then, if you want. You could also mark the water level inside the pool with painter's tape, and check the level again in a few days. Strong wind will lead to some evaporation but if it is over an inch you may want to start looking for leaks in the liner. Sometimes when pools freeze solid little tears develop in the liner. Liner age combined with cold weather make the vinyl more brittle and prone to break.
Yeah. I'm starting to think that the liner is torn. That will be a real pain to deal with.