Draining pool with no main drain and no hydrostatic valve


Active member
Sep 2, 2016
Hello everyone, I'm coming up on my first pool opening season on about a 30 year old pool. Im draining the pool using a large water pump because I need to paint and try my best to make the pool look nice. The main drain is closed off because of a leak. I honestly have no idea if there is a hydrostatic valve. I'm going to wait until about June so I can get a nice dry period so hopefully there is less ground water. What precautions can I take to avoid heaving scenario. Its a concrete pool, can I drill holes to let ground water into pool? How do I drill holes underwater? Please help. Thank you.


TFP Expert
LifeTime Supporter
Jan 6, 2010
San Dimas, CA (LA County)
How close is the ground water to the surface where you live? Any year-round creeks, lakes, or natural ponds nearby? I know in my state, the department of water resources has a website where you can find the nearest monitored wells and it will tell you how deep the water is. If it turns out you're on a ridge and the nearest well is 100 ft deep, you're in great shape. So I'd hunt for something like that.

I'd never want to drill a hole in the pool. That's just begging for a leak.


TFP Expert
Apr 19, 2013
Sacramento, CA
Ok there are several alternatives here.

As Richard states you can talk to someone and find out how deep your water table is where you live. If its high there are several alternatives.

First is drill a hole in the pool. For you that presents several problems. You probably don't have a hammer drill that could do it though you could rent one. You aren't in the business of drilling holes and filling them so it would be a learning experience and finally its difficult to paint a pool with ground water in it.

Next is drill some dry wells around your pool see what the water level is and pump it down so its below the level of the pool while you are paining. Again you need to find somone to drill the wells and rent the pump or pumps to keep it dry.

Finally we at TFP generally don't recommend painting pools. Generally it only looks ok for a couple of years and starts going down fast after that.


Mod Squad
TFP Expert
Apr 4, 2007
SW Indiana
I should have stated my house runs on well water and my well is 100 ft deep with the water table at about 80 ft. Does this help at all?
That will just be the level of the particular underground water source the well casing reaches. My well is 380ft deep, and the water level comes up to about 170ft, but if I dig a 4ft posthole it will get 6" of water in the bottom now. This time of year there may be much more water near the surface, and a single storm can increase it greatly. The upward force from the water can be more than you might imagine, so tread carefully. Summer would be a better time to do it.