Finding a water leak in a buried line

[Mustard Tiger]

I'm currently digging a 300+' trench for a yard hydrants (one for a greenhouse and garden, one for the burn pile and another for a small orchard that I'll eventually put in) and our frost line is only 24" so the trench is 3+ feet deep and in very rocky soil, so I already am worried about leaks. I have 16 tons of quarter-minus being delivered today to line the bottom of the trench and bed the PEX pipe to mitigate soil shifting and abrasion from rocks. Given your trench is that deep you wont see any surface water or things other posters have suggested like greener grass in a certain spot, etc. Best bet would be to dig a new trench. You could also start digging up the old trench and might get lucky and find the leak at some point. Just make sure you bed the new trench properly to minimize any increased chance of leaks or breaks in the the future.

Recently fixed a cracked sprinkler line at a friends place. She said the water was just bubbling out of a sprinkler head and wasn't reaching the sprinkler heads beyond the one bubbling. Was pretty easy to narrow down where the leak was. Make a few plugs with scrap PVC and caps to seal off specific heads and low and behold the water started coming up out of the ground where the leak was and was an easy fix.

Then there is the super cheap, thin-walled PVC that the previous owner oof my place used for irrigation that was literally 3 inches under the surface in the rocky soil and had apparently been there for decades. Never cracked, split or was damaged. They'd shut it off and drain it each winter to prevent freezing. Can't believe I never damaged it with the tractor when my neighbor and I were out there pulling and pushing over stumps, spinning tires in the dirt, etc. I was able to pull it out with my bare hands like a loose thread on a sweater, hence the reason I'm digging the new trench.

Good luck OP in whatever you end up doing and hope it's an easy fix.

 

[imarobot]

I assume you have looked for wet spot in soil. Few lines are more than 24 inches deep here so water usually surfaces when there's a leak. I've hired leak detection services that used something like a statoscope to find leaks beneath concrete. Not sure that works for a situation like yours but the fee is reasonable.

My line is 4-5' underground and the ground down that far is very sandy, so water will never make it near the surface.

 

[imarobot]

I'll correct you in that your water line is probably not 4 to 5 feet below the frost line as that would put the water line in at 8 to 10 feet.
Even at 4 to 5 feet deep your going to have a tough time finding a leak.
The most logical is abandon the old line and dig a new line using ABS or PEX as both hold up much better to all underground conditions then PVC.

Correct line is 4-5' down which is below the frost line, not 4-5' below the frost line as I mentioned.

 

[imarobot]

Look where the grass is the greenest.

But 4-5 feet down it may not make a difference. That's a deep water line.

Like others said, put in a new line. 2 feet should be deep enuf.

Edit: Never mind the 2' depth. Go deeper.

Grass is greenest above my leach field
This line runs under my driveway and there is no grass. At the depth of this line, and the sandy soil, water would never make it up hight enough for grass to be happy.
Yeah, 2' would freeze the line.

 

[imarobot]

I would try to run a new smaller line thru the old leaking one. I would take a piece of foam or cork connected to some fishing line and flush that thru. Then I would use the fishing line to pull thru some heavy twine that I would then attempt to use to pull thru the new tubing. If things didn't go well I would add a tube of grease to the recipe. You don't need much flow to feed chickens. Good luck.

I was thinking of doing that. I wish I had used a larger line and ran the water line inside of it when I installed this. But this was many years ago when I was not as smart as I am now.
I would like to have a larger line as I use this more than just watering chickens.

 

[imarobot]

How do you know there is a leak?

Is there a frost hydrant that you use for watering? I'd bet the hydrant is leaking before the actual pipe unless it was poorly installed or in rocky ground.

Stick your ear on the hydrant pipe.

I have a water flow meter that shows water flow.
The hydrant is a dry hydrant that allows me to use it in the winter.
I will check it to see if I hear anything at the hydrant.
The water line is in sandy soil.

 

[jaxs]

After reading about the guy who installs a stop valve in line when fixing leaks an idea came to mind. Dig to line midway (75') and install a stop. If it still leaks install another stop midway of first stop and where line begins. 3 and possibly 2 stops could narrow it down to digging up 20' of line. If stars are in alignment and you are lucky water will follow pipe to enter first hole letting you know which direction leak is from hole.

 

[D2Cat]

I'm sure it's been mentioned, but before doing any digging check for a leak at the base of the hydrant. You can listen by your ear if you have good hearing, or a screwdriver with steel on riser and plastic to ear, or best is a stethoscope like listening for engine noises.

Often times the rubber stopper gets wear and leaks there. Can pull the rod up and replace parts without digging.

 

[Scm]

at the base of the hydrant.

FWIW. In the 16 months we have lived here so far, I have replaced 4 out of 5 of the blue hydrants ($50) that were no more than 5 years old. They all cracked in the brass valve at the bottom. Spend the money and buy ($160) something decent. I already bought the 5th ones replacement..

 

[Mustard Tiger]

FWIW. In the 16 months we have lived here so far, I have replaced 4 out of 5 of the blue hydrants ($50) that were no more than 5 years old. They all cracked in the brass valve at the bottom. Spend the money and buy ($160) something decent. I already bought the 5th ones replacement..

Yep, read too many stories of the cheap $50 hydrants from Home Depot failing. Ended up getting four Merrill hydrants from a local plumbing supply. They're made int he USA. About $130-$150 each.

 

[imarobot]

I'm sure it's been mentioned, but before doing any digging check for a leak at the base of the hydrant. You can listen by your ear if you have good hearing, or a screwdriver with steel on riser and plastic to ear, or best is a stethoscope like listening for engine noises.

Often times the rubber stopper gets wear and leaks there. Can pull the rod up and replace parts without digging.

I did replace the rod and rubber stopper, but still leaks. That doesn't mean it couldn't be some other part down there leaking.
I'll have to put my ear to it and see if I hear anything.

 

[imarobot]

Yep, read too many stories of the cheap $50 hydrants from Home Depot failing. Ended up getting four Merrill hydrants from a local plumbing supply. They're made int he USA. About $130-$150 each.

Not a cheap hydrant, bought it at a farm store. That was many years ago (probably when a good one cost $50) so it is quite old and tired.
I hope that's all it is.

 

[JimmyJazz]

if your soil is sandy have someone use a trencher to run the new line. Im sure you could rent one and do it yourself. Good luck.

 

[imarobot]

Well I put my stethoscope on the hydrant, turned on the water and couldn't hear anything. When I turn the faucet in my basement on I can here water running, lot's of it, so it looks like my hydrant isn't leaking.

 

[imarobot]

if your soil is sandy have someone use a trencher to run the new line. Im sure you could rent one and do it yourself. Good luck.

Soil is sandy 3-4' down. This line runs across my gravel driveway. Looks like I'm going to have to start digging up my driveway with my BH92 backhoe.

 

[lynnmor]

Soil is sandy 3-4' down. This line runs across my gravel driveway. Looks like I'm going to have to start digging up my driveway with my BH92 backhoe.

I don't know how big of a bucket you have, but I would price out renting a trencher to minimize the mess and save a lot of time.