Every pool loses water to evaporation — about a quarter inch a day in a Cincinnati summer. Losing more than that means a real leak, and a real leak never fixes itself. It inflates your water and chemical bills, washes out the soil supporting your pool and deck, and in winter it can drop water below the skimmer line at exactly the wrong time.
Finding a leak is detective work with the right tools: isolating whether the loss is in the shell, the fittings, or the plumbing, then pressure-testing lines and pinpointing the failure — so the repair is a targeted fix instead of exploratory digging.
First: confirm it's actually a leak
The bucket test separates evaporation from leaks in 24 hours: set a bucket of water on a pool step, mark both water levels, and compare the next day. If the pool dropped noticeably more than the bucket, you have a leak. Two more free clues: if the pool stops losing water with the pump off, the leak is likely on the pressure side of the plumbing; if it loses more with the pump off, suspect the suction side.
How professional detection works
A systematic hunt, cheapest checks first:
- Isolation testing: plugging lines to determine shell vs. plumbing loss
- Pressure testing each plumbing run to find the failing line
- Dye testing around skimmers, returns, lights, and liner seams
- Fitting and gasket inspection — the most common culprits and cheapest fixes
- Precise location marking so any dig is one small hole, not a trench
Why leaks are urgent in this climate
In summer a leak is expensive; in winter it's destructive. Cincinnati's freeze-thaw cycles turn saturated soil around a leaking pool into a heaving, settling mess that cracks decks and stresses walls. And a closed pool that leaks below the cover line can drop far enough to damage the cover, the liner, or the shell. Any pool that can't hold level going into fall should be diagnosed before it's closed.
Pool Leak Detection: common questions
How much water loss is normal?
Roughly 1/8 to 1/4 inch per day from evaporation in a Cincinnati summer, more on hot windy weeks. An inch or more per day is a leak, full stop.
How much does leak detection cost?
Professional detection typically runs $250–$500 depending on pool complexity, usually credited toward the repair when the same company fixes it. Simple fitting and liner repairs found in the process are often modest fixes.
Can a leak be fixed without draining the pool?
Often yes — liner punctures, fitting gaskets, and many skimmer repairs are done wet. Plumbing repairs need excavation at the located point, which is exactly why precise detection matters.
My water bill spiked but the pool looks fine — possible leak?
Yes, if you have an autofill device quietly topping off a leaking pool. Shutting off the autofill for 24 hours and watching the level will tell you fast.