What to Do If You Think You Have a Pool Leak: A Simple Guide for Homeowners
A swimming pool is meant to be a place of calm—not stress. So when you start noticing the water level dropping a little too quickly, higher-than-usual water bills, or damp spots around your yard, it’s natural to wonder: Do I have a pool leak?
The good news is that not every water loss means a leak, and there are simple steps you can take to figure out what’s going on before calling a professional.
1. Start With the Basics: Is It Really a Leak?
Before assuming the worst, rule out normal causes of water loss:
Check for Evaporation
Depending on your climate, pools can lose up to ¼–½ inch of water per day just from evaporation, especially in hot, dry, or windy conditions.
A quick test:
Fill a small container with pool water.
Place it on the pool steps so it’s partly submerged.
Mark the water level inside the container and the pool’s waterline.
Wait 24 hours.
If both water levels drop the same amount, it’s evaporation—not a leak.
Inspect Your Pool Equipment
Sometimes leaks appear in the equipment, not the pool structure. Check:
Pump
Filter
Heater
Valves
PVC joints
Look for drips, spray, puddles, or unusual moisture when the system is running.
2. Next, Look for Signs of a Real Leak
If water loss is consistent and greater than evaporation, start looking for clues:
Inside the Pool Area
Cracks in the tile, plaster, or coping
Loose or hollow-sounding tiles
Wet spots or algae growth in the same area
Air bubbles in the pump basket
Unexplained loss of pressure
Around the Yard
Soft, mushy, or unusually green patches of grass
Soil erosion
Standing water that doesn’t dry up
Structural shifting or deck movement
These signs suggest underground plumbing or structural leaks.
3. Perform a Dye Test (Simple & Effective)
If you suspect a specific area—like a crack, around the drain, light, or skimmer—try this:
Turn off the pool pump so the water becomes still.
Use leak-detection dye (or even dark food coloring).
Squirt the dye near the suspected spot.
If there’s a leak, the dye will get pulled into the crack or opening.
This won’t fix the issue, but it confirms you’ve found a problem.
4. Check the Pool’s Plumbing
Leaks often occur in the pool’s circulation system. Try this:
Run the Pool for 24 Hours, Then Turn It Off for 24 Hours
Compare the water loss:
More loss while the pump is running → likely a pressure-side leak (return lines).
More loss when the pump is off → likely a suction-side leak (skimmer or drain lines).
Same loss during both → likely a structural leak in the pool itself.
5. When to Call a Professional
While DIY tests are helpful, some leaks are nearly impossible to find without specialized tools. You should call a professional if:
✅ You’re losing more than ½ inch of water per day
✅ Your equipment pad is wet or flooding
✅ You see cracks you can’t diagnose
✅ Your dye tests are inconclusive
✅ You suspect underground leaks
✅ Your water bill has suddenly increased
✅ You don’t want to waste hundreds of gallons of water
Leak detection companies use:
Electronic listening devices
Pressure testing
Underwater microphones
Thermal imaging
Specialized dye and sonar tools
This can save you time, money, and avoid unnecessary excavation.
6. Why Acting Quickly Matters
A leak isn’t just an inconvenience—it can become a costly problem:
Structural damage to your pool
Erosion under your deck or patio
Damage to landscaping
Rising water bills
Strain on your pool equipment
Fixing a leak early can save you thousands later.
Final Thoughts
If you think you have a pool leak, don’t panic. Start with simple tests, check common problem areas, and rule out evaporation. But if you can’t locate the issue—or if the signs point to something more serious—bringing in a professional is the best move.
Your pool is an investment, and catching leaks early keeps it safe, functional, and enjoyable for years to come.
