Is My Pool Leaking or Evaporating?
How to separate normal evaporation and splash-out from a likely pool leak without guessing or draining the pool.
Reviewed August 29, 2026 · About 6 minutesStart with what you can verify.
- Mark the water level and confirm that an autofill is not hiding the loss.
- Look for wet soil, settling pavers, dripping equipment, or water around waste and backwash lines.
- Note recent wind, heat, swimming, splash-out, vacuuming, and filter backwashing.
- Check whether the water repeatedly stops falling at the same fitting, light, skimmer, or return level.
What the symptom usually points to.
Loss matches the bucket
Evaporation is the more likely explanation. Repeat on a calmer day if the weather changed during the test.
Pool loses more than the bucket
A leak is more likely. Record the difference and move to careful visual observations.
Loss is greater with the pump running
A pressure-side plumbing, return, heater, filter, or equipment-pad leak becomes more likely.
Loss is greater with the pump off
A suction-side line, vessel, shell, liner, fitting, or hydrostatic condition may be involved.
Take one controlled action at a time.
- 1
Run a 24-hour bucket test with the pump operating on its normal schedule and no swimming.
- 2
Photograph the pool and equipment pad at the start and end, including the water marks.
- 3
Repeat the comparison pump-off only if your pool can safely sit without circulation for that period.
- 4
Tighten only accessible hand-tight unions or drain plugs that are clearly identified and visibly leaking.
- 5
Bring your measurements, photos, and pump-state notes to a leak professional if the source remains uncertain.
Stop here and use qualified help.
- Do not enter the pool alone to inspect a main drain or suction cover.
- Do not pressure-test buried plumbing, open energized equipment, or excavate around lines yourself.
- Do not substantially drain an in-ground or vinyl pool without a pool-specific plan; groundwater and liner movement can cause major damage.
- Stop using the pool if a suction cover is loose, broken, or missing.
Verify your exact model and product label.
Model families, controls, water conditions, and local requirements vary. These official resources are a starting point; the label and manual for the exact equipment or chemical control the work.