A leaky underground water pipe.

[geordief]

I have a leak that I am finding hard to pinpoint and I have an idea to put dye in at the in end and see where it comes up.

Is there any dye that  would work better than others?

 

The pipe is running under a gravel courtyard and so it should be easily visible if the dye comes up (maybe a foot at most) to the surface.

 

Otherwise it continues through a long section of the long grass of an overgrown orchard and I have never discovered a damp spot so would simply need to replace the whole length of this ancient outdoor plumbing  if that is where the leak(S?) is.

 

This is not drinking water so I can be quite unrestricted in any dye I use.

[dimreepr]

If there's no obvious damp patch, why would coloured water be more evident? 

[MigL]

I don't know where you live, but if there was a leak in the grassy area, you would notice much greener grass in one spot, after a dry period.
( typically end of July- August in North America/Europe )

Again, I don't know where you live, but if you get freezing weather in the winter, and you do replace the pipe, you might want to go deeper than a foot.

[geordief]

52 minutes ago, dimreepr said:

If there's no obvious damp patch, why would coloured water be more evident? 

We don't get many dry spells here.  I have waited for them and searched then but the area is pretty overgrown and ,for all I know the pipe may go under a rocker/flower bed(I didn't put it in)

 

It might be more obvious I'd have thought .... actually what would be obvious might be to put a  a bit of kerosene in the pipe  but I'd hesitate  to do that  as it would harm  the insects and I might need a lot if the leak  is a long way along the pipe (it goes about 100 metres at a guess)

[michel123456]

What kind of pipe? Metallic? What diameter (inside & outside)? Where does this pipe comes from (the roof?) & where does it go?

[John Cuthber]

48 minutes ago, geordief said:

We don't get many dry spells here.  I have waited for them and searched then but the area is pretty overgrown and ,for all I know the pipe may go under a rocker/flower bed(I didn't put it in)

 

It might be more obvious I'd have thought .... actually what would be obvious might be to put a  a bit of kerosene in the pipe  but I'd hesitate  to do that  as it would harm  the insects and I might need a lot if the leak  is a long way along the pipe (it goes about 100 metres at a guess)

Depending on what the pipe is made of, and used for, you may find it impossible to get the kerosene out completely, in which case you will need to dig the whole pipe out and replace it.
If you start digging at one end then you will, on average, only have to dig up half the pipe to find the leak.
 

[geordief]

1 hour ago, John Cuthber said:

Depending on what the pipe is made of, and used for, you may find it impossible to get the kerosene out completely, in which case you will need to dig the whole pipe out and replace it.
If you start digging at one end then you will, on average, only have to dig up half the pipe to find the leak.
 

I wondered where that post of mine went.I was going to delete it as that kerosene idea was a bit barmy  but  I couldn't find it for whatever reason.

Sometimes the software on this site is a step ahead of me....

I had the kerosene idea since it leaves rainbow coloured stains in the soil.

I just use this water for the garden really.

It is a pretty ancient system ,one inch metal pipes now well corroded  with ,I suspect one or two leaks along the line held together by compacted soil.

I did once attempt to dig it up starting from one end but ran into lots of fuscia and ivy  roots as well as a disappearing pipe...

[StringJunky]

41 minutes ago, geordief said:

I wondered where that post of mine went.I was going to delete it as that kerosene idea was a bit barmy  but  I couldn't find it for whatever reason.

Sometimes the software on this site is a step ahead of me....

I had the kerosene idea since it leaves rainbow coloured stains in the soil.

I just use this water for the garden really.

It is a pretty ancient system ,one inch metal pipes now well corroded  with ,I suspect one or two leaks along the line held together by compacted soil.

I did once attempt to dig it up starting from one end but ran into lots of fuscia and ivy  roots as well as a disappearing pipe...

How about forgetting about the exising pipe, except the two ends you cut, and fitting in a new section? Thew pipe sounds like it's perishing anyway, so you might as well leave it.

Edited September 25, 2020 by StringJunky

[zapatos]

You could pump some gas like butane into the pipe and then walk around where you believe the pipe to be with a gas detector.

[studiot]

1 hour ago, zapatos said:

You could pump some gas like butane into the pipe and then walk around where you believe the pipe to be with a gas detector.

Nice idea, don't forget to drain the water first. +1

 

There are (hireable) radio tracer heads that can be inserted into pipes, even quite small ones.

So michel123456's question on pipe size is pertinent  -  over to you geordief.

These tracers are usually floated down with the stream so again drain the pipe, insert the beacon head attached to a long enough string and flush through with water, whilst surface tracing with the detector.

[MigL]

1 hour ago, zapatos said:

You could pump some gas like butane into the pipe and then walk around where you believe the pipe to be with a gas detector.

Or a lit match...

No seriously, get rid of it altogether and buy a long garden hose.

[Ghideon]

9 minutes ago, MigL said:

No seriously, get rid of it altogether and buy a long garden hose.

Reminds me of a fix we did a long time ago at my parents' place. We dug down to a broken pipe at both ends and guided a slightly smaller hose through the pipe. That worked since the pipe had a larger than required dimension and the pipe wasn't too long. 

[studiot]

11 hours ago, Ghideon said:

Reminds me of a fix we did a long time ago at my parents' place. We dug down to a broken pipe at both ends and guided a slightly smaller hose through the pipe. That worked since the pipe had a larger than required dimension and the pipe wasn't too long. 

I had forgotton that lining of pipes is a common repair refurbishment technique.   +1

[John Cuthber]

15 hours ago, Ghideon said:

Reminds me of a fix we did a long time ago at my parents' place. We dug down to a broken pipe at both ends and guided a slightly smaller hose through the pipe. That worked since the pipe had a larger than required dimension and the pipe wasn't too long. 

That's the option that the local gas company took with all teh pipes round here. They fed a plastic liner into the main and sealed the ends to the original pipe.

16 hours ago, zapatos said:

You could pump some gas like butane into the pipe and then walk around where you believe the pipe to be with a gas detector.

Or not...
https://en.wikipedia.org/wiki/Stockline_Plastics_factory_explosion

[geordief]

26 minutes ago, John Cuthber said:

That's the option that the local gas company took with all teh pipes round here. They fed a plastic liner into the main and sealed the ends to the original pipe.

Or not...
https://en.wikipedia.org/wiki/Stockline_Plastics_factory_explosion

My pipe is so long (the stretch I suspect is over 30 metres and others are longer) that I would not have confidence in a length of stiff kerosene piping   going the distance since I am confident there is corrosion  having repaired  holes in the past.

What it might do ,I suppose  would be to actually locate the area that is holed. . Then I  could dig down with confidence   and maybe get some more years of life out of the system.

 

I have used this stiff kerosene piping to unblock the  sewage drains in the past .Again ,it can allow you to locate sections that are cracked so that you can repair them or ,with patience and flushing it  allows the blockage of paper and excrement to make its way to the end.

 

Those are much wider pipes ,of course . Since I repaired that cracked section there is much less maintenance and flushing works when necessary or ahead of time. 

[dimreepr]

53 minutes ago, geordief said:

My pipe is so long (the stretch I suspect is over 30 metres and others are longer) that I would not have confidence in a length of stiff kerosene piping   going the distance since I am confident there is corrosion  having repaired  holes in the past.

What it might do ,I suppose  would be to actually locate the area that is holed. . Then I  could dig down with confidence   and maybe get some more years of life out of the system.

 

I have used this stiff kerosene piping to unblock the  sewage drains in the past .Again ,it can allow you to locate sections that are cracked so that you can repair them or ,with patience and flushing it  allows the blockage of paper and excrement to make its way to the end.

 

Those are much wider pipes ,of course . Since I repaired that cracked section there is much less maintenance and flushing works when necessary or ahead of time. 

Dude, get a hose... But if money is no object, dig up the old pipes and replace them with new ones... 😉