How To Know Where Your Underground Pipes Are Located?

[tphaggerty]

The way I pressure tested:

Cap the return at the pool (real well). Open the return line somewhere after the filter (my returns have unions right after my SWG).

From Home Depot, you can get a pressure testing cap. Mine is for 2" pipe, is red, has a rubber gasket and an air filler (like on a tire) that has a wing nut on one side and a big washer on the other. They normally are on the very bottom shelf - only cost about 5 bucks. It fits in the open end of the pipe. You tighten down on the wing nut to seal it in, then use a compressor or tire pump to pressurize the line. BE REALLY CAREFUL, my pressure cap blew out several times before I could get it well seated. I would recommend duct taping it just to be safe.

If the line is leaking, the air pressure will drop (obviously). But, what worked for me (inadvertantly!!) - we had water in the line and where the air was escaping we could hear bubbling and gurgling, even through the concrete.

 

[NullQwerty]

The way I pressure tested:

Cap the return at the pool (real well). Open the return line somewhere after the filter (my returns have unions right after my SWG).

From Home Depot, you can get a pressure testing cap. Mine is for 2" pipe, is red, has a rubber gasket and an air filler (like on a tire) that has a wing nut on one side and a big washer on the other. They normally are on the very bottom shelf - only cost about 5 bucks. It fits in the open end of the pipe. You tighten down on the wing nut to seal it in, then use a compressor or tire pump to pressurize the line. BE REALLY CAREFUL, my pressure cap blew out several times before I could get it well seated. I would recommend duct taping it just to be safe.

If the line is leaking, the air pressure will drop (obviously). But, what worked for me (inadvertantly!!) - we had water in the line and where the air was escaping we could hear bubbling and gurgling, even through the concrete.

Thanks tphaggerty! Going to try that this weekend! Do you pressurize it to about 25 PSI?

 

[chrisexv6]

Have you tried calling a electric or pluming company? Some larger shops have locator's for finding Utilities. All they have to do is push a metal fish tape into your return and hook it up to the locator.

No, but actually you know what...This gives me an idea. I run a fish tape through the line and use my nephews metal detector to try to find it! If my concrete doesn't have the iron bars in it, this might work.

Still curious on the pressure test though...that might be the answers to all the problems if I can hear the leak without the geophones. Or if I pressurized it and could see it...maybe at the return fitting if I dug that up.

Worse comes worst I'll just run a whole new line myself as chrisexv6 did.

You can verify with the pressure test but it seems like youve done your homework to find out where your leak is. I went thru the same issue when my shallow end return was leaking. Overnight there was no loss because the filter was off. Fire up the filter during the day and in a matter of a few hours the water level was noticeably lower.

I was in denial as I didnt want to actually have to deal with fixing it, but in the end I just went for it and it actually wasnt hard at all (well, adding the new line anyway..........locating the leak in the existing would have been tough). The hardest parts of the whole ordeal was manhandling the Ditch Witch and finding good stainless steel clamps to hold the new pipe onto the return jet.

 

[underwater]

Two inches a night!

One would sure think you could go for the puddle of standing water. Even if you switch your vlave to only the deep end and really force the water out. I would think it would puddle up. Anyway, I have a very "primitive" way of finding underground pipes/lines. It's just a probe. It's a piece of 3/8 or 1/2 rod with a piece welded across the top to form a T. Sharpen the end and go stabbing! Those lines usully arent gonna be deep. Just pick a spot and stab. No luck move over about an inch and stab again. A lot quicker than it sounds. Should find it in less than 5 mins. Has yet to fail me. Good luck!
UW

 

[NullQwerty]

Two inches a night!

One would sure think you could go for the puddle of standing water. Even if you switch your vlave to only the deep end and really force the water out. I would think it would puddle up.

No puddles unfortunately. Probably just drains down, or it's not noticeable because the pipe is in fact under the concrete.

 

[mchristisen]

Plumbers have cameras that can be run in the pipe to find the break. Once the break is found they use a locator to find the camera head. Local plumber here in Austin wanted $300 to perform this service for us.

 

[sevver]

Plumbers have cameras that can be run in the pipe to find the break. Once the break is found they use a locator to find the camera head. Local plumber here in Austin wanted $300 to perform this service for us.

The camera I use would not fit in a pipe smaller than 3 inches, certainly would not go through a bend in anything less than that. The probe idea is a good one, although not through concrete, and hitting a small pipe and knowing you hit it is another story.

 

[NullQwerty]

Welp it rained all weekend and so I wasn't able to do the pressure test (even if I tried I wouldn't have been able to hear a leak with the rain going).

But right at the end of the day today (Sunday) it cleared up. So I decided to quickly dig out where my return line meets the pool (that's the spot where I have dirt instead of concrete). I had convinced myself that was where the leak was going to be and it was just going to be a loose metal clamp or something similar (to other peoples problems). Unfortunately I seem to have been wrong. After digging it out I ran the pump for about a 1/2 hour and waited and listened and felt around...but no signs of water.

I think for my next venture I'm just gonna try out the fix-a-leak stuff. It's $30 and I have read a few reviews online of people saying it worked for them. They use it in car radiators to fix leaks, right? It may be snake oil, but it's only $30 so it's worth a shot.

Otherwise...I think I'm going to just use the shallow end return line and deal with a non-sparkling clear pool. Either this summer or next I have to replace the concrete deck anyway (it's old and beat up), so at that time I'll replace the whole line.

I'll post back next weekend with the results of the fix-a-leak for those that are curious.

 

[Soundy]

Ancient thread revival! Pretty sure I have a return line leak as well - similar symptoms to OP's, with water loss and constant sand buildup when the pump is running. Some of these tips will be helpful!

Unfortunately in my case, there's one pipe out of the filter/boiler going down into the slab and then splitting out to two returns.