Winter is the worst time for a vinyl pool liner to start leaking. If the pool is tightly covered and closed for winter, that makes finding a patching a vinyl liner - inconvenient at best.
The larger concern is for the pool cover and the pool itself. The water level in your pool supports the pool cover, and if it drops too low - floating solid covers can fall in the pool, and anchored safety covers can become damaged under a heavy snow load. In addition to a potential problem with the pool cover, without water pressing up against the walls of the pool, the walls can begin to bulge or lean inward. Third, if enough water goes out of the pool, this can expose the liner to the elements, and allow it to relax and pull away from the wall.
HOW TO TELL IF A VINYL POOL IS LEAKING WATER
Keep an eye on the water level during winter. If the pool is covered, you can tell by how a solid cover lays across the pool surface. If it becomes very tight, or begins to slip toward the pool, that's a good indication that some pool water is escaping.
If you do use a solid pool cover with a cover pump, be sure that you're not pumping out pool water through small holes in the pool cover! Place the cover pump far away from any suspected holes, or place the pump on an upside-down Frisbee, to help prevent the cover pump from pumping out pool water.
Safety covers, those that anchor in the deck, will make vinyl liner leaks harder to find. With you cover tool, remove springs on one corner to check water level, or you can lift the skimmer lid and reach in through the skimmer to touch the water at the surface. Or on a sunny day, you can kneel down next to the pool and cup your hands around your eyes with your nose touching the mesh pool cover. This will allow you to see through the cover to inspect the water level.
Other leak detection methods for vinyl pools include inspection of the ground around the pool, or downhill from the pool. Especially for aboveground pools, soft and spongy areas outside of the pool, or areas where the grass is a bit greener, are strong indicators that the pool is leaking, and probably close to that area.
HOW TO FIND A VINYL POOL LINER LEAK
The first task is to locate the leak (or leaks) in the pool. If the plumbing lines are winterized and plugged, you can rule out these as leak sources. That leaves the pool light, step sections and anywhere else that the liner was cut on purpose (return and skimmer wall plates).
Of course, vinyl liners can also leak when they are punctured, or become brittle from chemicals and ultraviolet light. When the vinyl liner is leaking, the hole may be very small and hard to find. One giveaway is noticing small bits of debris stuck onto the vinyl, at or near the water line. The waterline itself is another giveaway, assuming that the leak has stabilized at a particular level. Food coloring can be used as dye, to dye test suspect areas around the pool. Wear a dive mask so you can see if the dye is being sucked out of the pool.
If your pool is covered for the winter, you'll want to remove the cover for a complete leak analysis. In many cases, the cover can be folded on itself towards the middle of the pool, so that it's just covering the center of the pool's length.
HOW TO PATCH A LEAKING VINYL POOL LINERThere are three types of patches for patching vinyl pool liners:
- Liquid Patch, which squeezes out of a toothpaste type of tube, and is smoothed with your fingers
- Self-Adhesive patches. Cut to a rounded shape, 20% bigger than the hole, and just peel and stick.
- Wet/Dry patch kits. Cut out a rounded vinyl patch, spread glue and quickly stick it over the hole.
In my opinion, liquid pool patch is the easiest to use and most durable, followed by the Wet/Dry vinyl patch kit. The self-adhesive type of patches are good for a quick fix, but may begin to peel and curl on the edges after some time.
There is another solution available for pool leaks, using Marlig's Fix-a-Leak, which is an emulsion chemical that seals up leaks the way blood cells clot and form a scab on minor skin cuts. Fix-a-Leak is most effective when you know where the leak is, so that the product can be concentrated in one area. It can be used to seal up leaking faceplates, pipes, lights, steps or vinyl - but works best when you can build a large box of wood or plastic, to isolate the area and contain the chemical for a few hours.
WAITING UNTIL SPRING TO PATCH THE LINER
That is always an option - if the leak is not too fast, and you are having trouble locating or patching it during winter, you could Add Water to fill the pool back up, and keep a close eye on it, adding more water as needed.
Come springtime, when the cover is removed, look closely for debris stuck into small holes in the vinyl, or around any of the "made on purpose" cuts in the liner, such as the pool light, returns, skimmer and steps.
But - if you can patch it now, that's by far a better strategy, to protect the liner, the pool and the pool cover from potential damage from low water levels.
SPP Pool Expert