Pool Leak or Evaporation


New member
Apr 6, 2018
Sandy Springs, Georgia
I just had my pool refinished with pebbletec. While the water was out, they performed pressure tests to ensure no leaks on main, skimmers and return.

Water is back in now and water dropped an inch or two over the course of 2-3 days. I filled it back up and measured the water level. I turned off all equipment and measured each day for two days. After day 1, it had lost 1/2 inch, after day 2, another 1/2 inch.

The pool temp is around 65-70 and it is sunny with highs between 70-75.

Normally I would assume, since I'm not circulating water, that this must be evaporation, but that seems like a lot of water to lose per day.

As part of the renovation job they re-did the plumbing, but they "forgot" to change out the multi-port valve that I had paid to replace.

I am wondering if it is possible that the valve is allowing water to go to waste and the back pressure of water in the pool is forcing it out even though the pump is not running.

I closed the 3 way valve leading to the pump this morning, essentially shutting off the main and skimmers to see if it still loses water today.

Any other ideas out there? Would be very grateful. I haven't had a pool before so excuse my ignorance as I wade in to this new space.


Silver Supporter
Jun 21, 2017
Sachse, TX
Hello and welcome to TFP. Where is Sandy Springs? Please update in your profile and add your pool info to your signature (see mine for example).

1/2" sounds a bit high this time of year but depending on surface area, wind, humidity level, and sun it is not possible to know without a test. Check out this link and do the bucket test. Pool School - Leak Detection


Gold Supporter
May 16, 2010
Chapel Hill, NC
Do the bucket test to confirm evaporation, although 1/2 inch a day is way higher than I would expect in Atlanta and at this time of year (maybe 1/8" a day in the peak of the summer).