The bucket test
- Fill a bucket with pool water to about one inch from the top.
- Set it on a pool step so its water level is the same as the pool's.
- Mark both levels on the outside of the bucket and inside the pool wall.
- Leave it for 24 hours with normal use.
- Compare. If the pool dropped more than the bucket, you likely have a leak.
Where pool leaks happen
- Return and suction plumbing, often underground.
- Skimmer throats and fittings.
- Light niches and conduits.
- Cracks and tile lines in the shell.
- Equipment pad: pump seals, filter, heater and valves.
Pump on versus pump off
If the pool loses more water when the pump runs, the leak is probably in pressure-side plumbing or equipment. If it loses more when the pump is off, the leak is more likely in the suction side or the shell.
Northern Illinois and winter
Pools here are closed for winter. Water left in lines can freeze and crack plumbing, and the damage often shows up at spring opening. Test pressure on lines after opening and watch levels for the first weeks.
When to call a specialist
Dye testing, pressure testing and underwater listening can pinpoint a leak. See pool and spa leak detection, and consider irrigation leaks and exterior leaks if soggy ground appears near the pool.
