Identifying Water Pipes

[echnidna]

I have 2 polypipes underground.

Theyre both identical pipes

One carries rain water, the other carries creek water.

I need to tap into the creek water pipe.

How can I distinguish between them before cutting the polypipe.

Could I use a stethescope and hear water running through a pipe?

Or is there another way?

[Burnsy]

You could try isolating the pipes one at a time and listening for water running, will probaly have more luck if you isolate both then have somone turn one on while you stand in the hole where they are listening, you should be able to hear the initial rush of water through.

If this does not work, you can buy PVC clip over fittings for tapping into pipes. They are a T that has the through pipe split and the off take T is usually sealed. You glue the T in place by snapping it over the pipe that is to be tapped into. Once dry, you drill a hole through the offtake into the main line. You could do this, then you have a 50% chance of hitting the pipe you want the first time. If it is the wrong pipe, just glue a end cap into the offtake.

This is probably as clear as mud if you have not seen one of the T's I am talking about.

Keep in mind that this is the best way to tap into a buried pipe even if you know which one is the one you want. Joining into buried pipes using conventiaonal joiners is a right pain in the rear if you can't lift enough of the pipe to flex it open to slot the joiner in.

[joe greiner]

Flush hot water into whichever one has an access point. Touch the pipes at the work location, and see which one gets warm. (Assuming you're not under water use restrictions.)

Joe

[ian]

I have 2 polypipes underground.

Theyre both identical pipes

One carries rain water, the other carries creek water.

I need to tap into the creek water pipe.

How can I distinguish between them before cutting the polypipe.

assuming that for health reasons you MUST correctly identify the right pipe, I can't see any other way other than dying the water source (use flourescent dye or lots of food colouring) you want to tap into, drilling a hole into the pipe, and checking for coloured water at your tap point.


ian

[rodm]

If you can drain one of the pipes (from either end) it might be easier to tell which one is still carrying water.
You don't say what type of poly and if it is just ag poly it should be cheap enough to just take a chance with a T and if you are wrong then put in a joiner. You will have to shut off the supply of at least one to determine this though.

[rrich]

I

Could I use a stethescope and hear water running through a pipe?

Or is there another way?

If it were me I would go the stethescope route. Just put a radio, boom box or getto blaster up in the rain gutter. Use the stethescope to listen for the music(?) and you'll have the correct pipe.

[bitingmidge]

Connect one. Either one, pick it at random and complete the job.

Now you can be sure it's not the one you need, so repair it, and do the other one.

Works every time.

P

[Bleedin Thumb]

Get someone to tap the pipe with a hammer and put your ear on it. It only works if you are within about 15 - 20 metres after that the sound has dissapated. If its a longer run you could put an electric eel down it - if you can get the use of one without the cost of the plumber on the end!

Edit : Just a thought what about a hose with a nozzel should make enough noise when fed into the line.

Good luck.

[ian]

I have 2 polypipes underground.
Theyre both identical pipes
One carries rain water, the other carries creek water.
I need to tap into the creek water pipe.
How can I distinguish between them before cutting the polypipe.
Could I use a stethescope and hear water running through a pipe?
Or is there another way?

sound carries through water better than it does through air.

If you can be sure that the pipes are not accousticly coupled (i.e. sound in one pipe can't jump across to the other) after filling the pipe you want with water so there is NO air gaps, you should be able to hear a sound pulse travelling along the pipe

Hopefully soundman can suggest how to get the sonar "beeb" going underwater

ian