Locating & Fixing Pool & Spa Leaks

Swimming pool, spa or hot tub leaks can be the result of routine wear and tear, carelessness, accidents or the effects of wintertime conditions.  Not all loss of water can be attributed to a leak.  Losses, due to evaporation, splash out or backwashing, are normal and are expected.  Excessive water loss, more than 1/4"-1/2" daily, should be investigated.  Products are available to help determine if there is a leak, where the leak is located and to help seal the leak.  There are companies that specialize in pool and spa leak detection and repair.  Sometimes the leak turns out be to in an easily accessible place and other times it is under decking or the pool or spa floor.  In that case, it may be time for a professional leak detection service, to help  locate the exact source and minimize any repair damage.   Clicking on the underlined and highlighted "keywords" or "catch phrases," in the archived answers will give you access to additional information on that topic or product.  Please refer to the Glossary, if there are terms or phrases that require explanation.

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► Major Leak?

Alan, I have a concrete inground pool, around 17000 gallons.  I think?  The pump went out and the pool was sitting for about 5 days while a new one was in transit.  Upon receiving the new pump, I installed it myself.  No big deal- right?  Problem is that now when the pump kicks on it sucks about 2 and a half inches out of the pool in a 4-6 hour span. There is a small leak by the little bowl up by the valve handle that says filter, backwash, winterize, etc. And also a small leak by the auto chlorinator. The pump does build up to 18-20 lbs. of pressure and the jets on the side are putting out good pressure, and it seems the loss only occurs when the pump is running. HELP PLEASE. Thanks.

Carl, 1/28/2007

Your water loss is about 1000 gallons and is probably due to a cracked pipe or loose connection, in the return lines (because the leak is more noticeable when the pump is running, and is not sucking air into the pump, it is probably in the pressure not suction side of the plumbing).   Given that this is a major leak, nothing short of a proper repair is likely to solve the problem.  I suggest that you consider a leak detection service, to help minimize the repair efforts, by locating the leak.  By pinpointing the location, excavation will be kept to a minimum.  For more information go to:  www.poolleak.info  To get a better fix on the actual water loss,  multiply the number of square feet of pool surface by 0.62.  Multiply this by the loss in inches and you have the gallons of water lost.  Those drips could not possibly account for this type of water loss.  Nonetheless, they should be fixed.  I hope that this information will prove helpful.

Sincerely.  Alan Schuster, 1/29/2007

► Possible Leak Under Decking?

I have a leak that loses more than an inch of water daily.  Based on the aerated return flow, it seems to be located in the return line, furthest from my filter.  I have tried several things, but nothing has worked.  The dealer thinks that it is a cracked pipe, that resulted from poor winterizing.  Given the location of the leak and all of the decking that is around the pool, do you have a suggestion that will help minimize the repair?  I don't want to have to break up more of the concrete than is necessary.  Thanks for any help.

Craig B., Eastport, NY 7/13/2006

A cracked pipe is subject to change and things could suddenly change for the worse.  I suggest that you call in a leak detection specialist.  Anderson Manufacturing supplies the equipment and knowledge and professionals use to help pinpoint the location, making it possible to minimize the amount of concrete or decking that will be involved in the repair effort.  For the location of a leak detection professional, in your area visit their website at:  www.poolleak.info  This should be far less expensive, than approaching the location blindly.  Good luck and I hope that I have been helpful.

Sincerely.  Alan Schuster, 7/14/2006

► Spa Leak Detection?

I have a built in spa and I am losing at least one inch daily.  Any suggestions?

Larry G., 12/12/2006

The leak could be most anywhere.  First check and inspect all connections that are accessible.  Adding Fix A Leak could help, if the leak is less that 1/8" in diameter.  It is worth a try.  If the leak is due to a crack, the line might have to be replaced or repaired.  If you want to avoid digging up the entire perimeter of the spa, to blindly look for the leak, you might want to call in a leak detection professional.  They use special equipment to locate the leak and minimize the repair work.  Good luck and I hope that this information proves helpful.

Sincerely.  Alan Schuster, 12/12/2006

► Measuring The Pool Leak?

I have a 30,000 gal inground pool. I just got a new liner a filter and pump installed last week. I had got pressure testing done on my 1 return and 2 sections lines before this job as the pool is old that was normal. Now I am losing about 1/2 an inch of water every day , I also see an air bubble, out of the return, every 15 seconds or so when the filter is off. Could you please guide me in the correct direction as to what needs to be done?  Is it certain that I have a leak?  Thanks.

Gary, 7/15/2005

A 1/2" a day is about what you would expect to lose, if the pool was in hot, direct Sun and in a breezy, dry area.  I suspect that you do have a leak, but the loss, is partially due to evaporation.  If you would like to confirm the extent of the leak do this:  place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool.  The next day determine the water loss in the pool and in the bucket.  The loss in the bucket is due to evaporation.  If the pool lost more, that portion is due to a leak.  Usually, leaks in the suction lines show up as air leaks (aerated return flow), when the pump is running.  If water is leaking out, air should not be bubbling in.  This would also apply to the main drain line.  I would check all of the seals, gaskets, o-rings and connections.  There are dye solutions that can help you trace a leak.  There are companies that specialize in leak detection and can help locate the leak and minimize repair damage.  I hope that this information proves helpful.

Sincerely.  Alan Schuster, 7/16/2005

 
► An Unseen Hole Poked In A Liner?
 
We have a 24' above ground pool in which we just installed a new liner.  We noticed yesterday that there is water leaking out on one side of the pool.  The pool is approximately 10 years old and when we replaced the liner there were no damages to the "shell" of the pool.  Where could the leak be coming from?  It looks like it is leaking around the bottom of the shell.  I didn't notice any damage to that area either.  How could the water be leaking out in that area when there is a new liner in the pool?  We haven't finished filling up the pool yet nor re-installed the skimmer or pump as we were wanting to resolve this problem as quickly as we can.

Marie W., 7/23/2007

There could be bad seam.  Call the dealer, as he might offer to repair or replace.  You should try locating the leak with a dye locating solution.  Dealers sell this product.  It is dripped into a still pool and the dye traces the way to the source of the leak.  There are also companies that specialize in leak detection, by using specialized equipment.  Are you certain that the liner is the problem?  Once you locate the hole in the liner, repair is simple.  Boxer Adhesives makes a line of vinyl repair kits and patches that you can use.  They are designed to be applied under the water, so draining the pool will not be necessary.  I hope that this information proves helpful.

Sincerely.  Alan Schuster.  7/23/2007

Thank you for getting back with me.  I truly do not believe that the liner is the problem.  The water is coming out at the base of the wall of the pool.  Before we replaced the liner we noticed the same problem with the old liner, but we replaced it because the liner was about 10 years old and we knew that there were some torn places in the liner.  I don't understand how the water could be leaking out unless there is a hole in the liner.  I guess I'm just assuming that since it is a new liner there would be no holes.  The ground around the pool is really saturated and I'm at a loss at what could be the problem.  Should we do the dye test and see if maybe the seams are in fact leaking?

Marie W., 7/24/2007

A dye test makes sense.  It should point to the location.

Good luck.  Alan, 7/24/2007

Just wanted to let you that we think we have found the problem.  Apparently,  when we put the hose in the pool to fill it up, it hit the bottom of the pool and poked a hole in it under the ladder.  We did do the dye test and the color just sucked right down the hole.  We have it full now, so hopefully everything is a go.  That underwater patch made the repair really easy.  Thank you so much for your help.

Marie W., 7/25/2007

 

► Stains And A Leaky Pool?

I was elated to find your site.  We have a 12X24 concrete pool not quite 5 years old.  We live in central Florida.  My first question is related to the stains we are experiencing.  They began as small light and dark grayish swirls in one small section of our pool.  We went to our local pool supply store and they recommended a metal stain remover.  It did nothing and since the stains are growing!  They now cover most of the pool floor. 

My second question is related to a possible leak.  We seem to be losing about an inch of water per day.  We thought it was due to the recent cold temperatures at night.  However, it still seems like an awful lot of water to evaporate overnight.  I've scanned the side tiles for leaks and used food coloring to determine if there were any leaks but nothing appeared.  How can we determine if there may be a leak elsewhere, lines, etc?  Also, what is the average amount of water loss we should be experiencing? Thanks very much for anticipated help. 

Kathleen, Florida, 3/27/2004

Adding a metal treatment doesn't always work.  You might have to lower the pH to approximately 6.0.  Try this.  Put about 1/2 pound of pH reducer powder in a white sock and drop onto a stained area.  Leave in place for 15 minutes and then move around with the vacuum pole.  If it works, the problem is definitely a metal.  You can repeat elsewhere or use a stain removing accessory to siphon an acid solution onto the stains.  Once removed, add another dose of the metal treatment.  Thereafter, add monthly or whenever new water is added.  Refer to the archives on "Pool Staining Problems" for more on the subject. 

Finding a leak isn't always simple.  One inch per day is likely to be a leak.  Average water loss depends upon temperature, exposure, wind speed and other variables.  A loss of 1/4"-1/2" per day would be more realistic.  The leak could be in the main drain line or the skimmer lines.  A leak in the return line, could create aeration in the pool, but not necessarily a leak.  Try this.  If you would like to confirm the extent of the leak do this:  place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool.  The next day determine the water loss in the pool and in the bucket.  The loss in the bucket is due to evaporation.  If the pool lost more, that portion is due to a leak.  Close off the skimmer lines at the multiport valve and plug up the skimmer intakes.  If you are still losing water, the leak is not in the skimmer lines.  If it stops, the leak is in the skimmer line.  There are companies that specialize in leak detection and can help you locate the precise source of the problem.  In turn, this minimizes the work necessary to actually reach the site of the leak.  For more information and to locate a local leak detection professional go to:  www.poolleak.info  Good luck and I hope that I have been helpful.

Sincerely.  Alan Schuster, 3/27/2004

► A Small Pool Leak At Best?

I have a 14 x 28 inground kidney shape cement pool and the pool loses about a 0.25 inch of water daily.  I bought the house last year and had all the cement in the pool redone.  The pool was built in 1975 and there is a ground drain at the bottom.  The piping runs to my garage, where the pump, filter and heater are.  The heater is very old 1977, the pump is new and so is the filter.  Do you think the cap at the bottom may be loose, so water is draining out?  Let me know what you think.

Mike M., 1/31/2005

A loss of 0.25" per day is not conclusively a leak.  Given normal evaporation and splash out loses, that amount may be within normal expectations.  Such a leak would be quite small.  Any leak is somewhere below the level of the water and given the slowness, might take a considerable time to reach the level.  If you would like to confirm the extent of the leak do this:  place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool.  The next day determine the water loss in the pool and in the bucket.  The loss in the bucket is due to evaporation.  If the pool lost more, that portion is due to a leak. There are dye solutions that might help locate the leak.  Fix A Leak might be able to seal the leak.  For more information on this product, go to www.fixaleak.com  If there is a leak and you fail in your efforts to seal or locate it, you should consider calling in a leak detection professional.  Good luck and I hope that I have helped point you in the right direction.

Sincerely.  Alan Schuster, 1/31/2005

► Main Drain Leak?

I found your site on a search on Google and while I was searching for tips on fixing leak in the drain at the bottom the pool.  Is there a way that I can do this myself or do I have to have outside help, you think?  I appreciate any help you can offer.  Thank You.

Fred, 2/14/2005

A main drain repair can be a big deal or a very big deal.  It all depends on the problem and where it is located.  Fix A Leak can be used to seal the leak, if it is not too large and it not subject to expansion.  If it works, great!  If not, you should consider hiring a pool leak expert. Major leaks can cause extensive damage to your pool, if left for too long.  Go to www.poolleak.info, if you need to find a pool leak expert in your area.  Good luck and I hope that I have been helpful.

Sincerely.  Alan Schuster, 2/14/2005

► Finding A Pool Leak?

Alan, I have a pool that is leaking as much as three inches a day, and I'm confused about where the leak is located.  I thought the multiport valve might be leaking into the backwash while in normal filtration position. After five hours of filtration the pool lost about 1/2 inch of water. The valve is very old and I thought this may be the cause of the leak.  Then I did a drain down without running the filter. After two days the water level dropped to the base of the skimmer opening and stopped. However, when the water level is where it should be I can still vacuum.  So, I'm not convinced that the skimmer has a suction leak.  Any advice you could give would be appreciated. Thank you.

Stuart S., Boulder City, Nevada 3/15/2004

It would have been helpful to know what kind of pool this is:  above ground or inground, gunite or vinyl.  The problem is not the multiport valve because there would be evidence of water seepage that would be conclusive.  My guess is that this is an inground pool:  an above ground pool would have exposed lines and a leak is easier to find.  The fact that the water level dropped to the skimmer base, means that the leak is due to a bad seal in the skimmer, a crack in the skimmer, a bad line connection at the skimmer or leak in the line from the skimmer to the filter.  A leak in the return line would produce a lot of aeration, when the filter is in operation.  The leak could also be from another point at the height of the skimmer base.  I suggest that you do the following:  Fill the pool up to the normal level and shut off the filter.  Find a leak-detecting dye solution at a local pool professional store.  Basically, it will direct you to drop some dye, into the still water, and look for evidence of a water flow.  If there are steps, underwater lights or other through the wall items, you will have to check these as well.  Sometimes, leaks are in inaccessible location such as underground lines.  If you fail to locate the leak, I suggest that you call in a leak professional, as this is a major leak and there are companies that specialize in leak detection, using sound detection and other equipment.  I hope that I have been helpful and good luck.

Sincerely.  Alan Schuster, 3/15/2004