Owning a swimming pool is a great way to enjoy the outdoors, but nothing is more frustrating than watching the water level drop for no apparent reason. Before calling in the professionals, there are several simple and effective ways to track down a pool leak using essential household items. Following these steps, you can identify potential leak sources and determine whether a DIY fix is possible or if it’s time to call the experts.
Step 1: The Mark and Measure Technique
The best place to start is determining whether the pool is truly leaking or if the water loss is due to evaporation.
- Grab a piece of tape, a waterproof marker, or another visible indicator.
- Mark the water level on the pool tile or fiberglass steps (if it’s a vinyl liner pool).
- Let the pool sit undisturbed for 24 to 48 hours without adding water.
- Measure how much the water level has dropped using a ruler.
If the water level decreases by more than ¼ inch per day, there’s a good chance the pool has a leak. If it’s within that range, evaporation is likely the cause.
Step 2: Inspect for Cracks, Gaps, and Tears
Leaks often stem from visible cracks or weak spots in the pool’s structure. A thorough inspection of the walls, floor, and tile line can reveal problem areas. Taking a dive with goggles and a weight belt can make inspecting every corner of the pool easier.
Key Areas to Check:
- The skimmer – Look for cracks or separation in the skimmer throat or housing, as this is a common leak point.
- Return jets and fittings – Over time, these can pull away from the plaster, allowing water to escape. Check inside the fittings as well—cracks or a failing gasket in vinyl liner pools can also cause leaks.
- Tile grout lines – Deteriorating grout, especially in an attached spa, is another frequent issue.
- The pool light niche – A frequently overlooked area that can allow water to seep out.
- The main drain – Plumbing lines in the deep end can separate from the pool shell, making them difficult to inspect without diving.
Step 3: Perform a Dye Test
A dye test is an easy way to pinpoint the exact location of a leak.
- Turn off the pool pump to ensure the water is completely still.
- Using a dye pen, release a small amount of dye near cracks, seams, or suspected leak points.
- Watch closely—if the dye is pulled into a crack, hole, liner tear, fitting, or light conduit, the leak is confirmed.
- Using goggles and a weight belt for deeper areas of the swimming pool can make it easier to conduct the test up close.
Step 4: Look for Soggy Spots Around the Pool
Sometimes, the leak isn’t inside the pool itself but rather in the underground plumbing. Walking around the pool area and checking for unexpectedly soggy spots in the yard can indicate a broken plumbing line underground.
Step 5: Inspect the Equipment Pad
Leaks often originate from the pool’s equipment. You should check the pump, filter, heater, and valves for drips, moisture, or puddles. Loose connections and worn-out gaskets are common sources of equipment-related leaks.
Step 6: Inspect the Swimming Pool Light
The pool light is one of the most common yet frequently missed leak sources. The conduit behind the light fixture can allow water to escape rapidly.
How to Check the Pool Light:
- Ensure the power to the pool light is shut off. If necessary, turn off all breakers connected to the pool system.
- Remove the light bulb from its niche by loosening the single screw at the top.
- Check for cracks or damage inside the light niche, and conduct a dye test around the conduit at the back.
If the dye is drawn into structural damage, a special putty or sealant can provide a temporary fix. Butyl tape or Loctite has also been effective for sealing a leaking conduit.
Step 7: Perform the Shut-Off Test
This simple test helps determine whether the leak is in the pool structure or within the plumbing system.
- Fill the pool to its normal level and turn off the pump for 24 hours.
- If the water level continues to drop at the same rate, the leak is likely structural (such as cracks or liner tears).
- If the leak slows or stops when the pump is off but speeds up when it is turned back on, there’s a good chance it is in one of the plumbing lines.
In Conclusion
Tracking down a pool leak takes patience, but these techniques can help narrow down the source without professional equipment. Finding the problem early can save time, money, and excessive water loss.
Precision Leak Detection, based in Jupiter, Florida, offers expert swimming pool leak detection services if the leak remains elusive or requires professional attention. Contact us today for an accurate diagnosis and effective solution!
