Locating buried water services 2

[mflam]

This has to be a common problem.
In one street in my town there are two water mains.
A house could have been connected to either of the mains.
From the records, it is not possible to know for certain which line a given customer is connected to.
Does anyone have any cheap tricks?
What about sound? I was thinking about connecting a tone generator to the pipe in the house and sending out a tone, say 400 Hz.
Then take a stethoscope out to the street and listen at valves connected to each of the mains. Whichever valve has the louder tone, that should be the serving water main.
Any thoughts?

 

[btrueblood]

Shut off one main, then go house-to-house and check for low water pressure (or sit at desk in water service office and log phone calls).

Inject food-grade dye or "funny smell" (wintergreen oil?) into one main, and inspect as above...

The odds of propagating any noise down the pipe and through the various bends, past the meter...well I wouldn't hold my breath.

 

[gsroy2]

Now don't judge me, because I am just as skeptical of this method as you probably are. but the following has accurately shown me the location of pipes time and time again.

two brazing roads = 24=30" each. Bend each one in an "L" shape such that the small leg is about 6" long. Hold the 6" end in each hand loosly such that the long legs stick out straight in front of you and parralel to the ground. Walk over the area where the pipe is and the rods will turn inward when you cross the line. They will align in the same direction as the pipe.

I wouldn't use this method in itself, but it gives you a really good starting point. I keep two rods in my truck at all times.

No Kidding!

 

[hydrae]

Are the service lines metal?
If so, connect a locater to the service and find the main. if available, use the non jumping frequency.
If not metal, use the sound based locating devices available at water system supply outlets (not cheap). The sound based devices use water pressure to transmit a vibrating sound through the water and you listen using leak detection equipement.
Hydrae

 

[dicksewerrat]

I have always used the "witch wands" first. I have won bets with survey crews using them. But it makes all that study for my degree a little useless. Sound or the freq. detectors will work. Just as the main shutdown process.

 

[rconner]

Question to: gsroy2,

I made a couple of "brazing rod pipe locators" as you describe many years ago, I still have same in my office cabinet, and if I remember correctly it appeared I could locate several metallic lines with same (metallic lines were all I remember checking/having to check). Interestingly, I think also in some impromptu trials with some of my co-workers it appeared for some reason not all folks could use these tools with comparable results.
Was just curious, as I had not tried this, if anyone had been consistently successful locating non-metallic, non-marked buried pipe with similar tools?

 

[dicksewerrat]

Sure. they locate PE gas mains too. Ialso found out a funny thing about the witch wands. some people can't use them and others make the wands seperate instead of crossing.

 

[rconner]

I got some frightened when I saw the latest post by another implying "witch wands" may be used to "locate" non-metallic PE gas piping! (what little I had fooled with this many years ago was admittedly VERY non-scientific, before the cheap searching wonder of the web, not a controlled experiment in any terms, and I was not planning any digging around any pipe let alone gas pipe when I did this!) I did a brief search of the web and found that there is now much info "out there" on this subject, at least with regard to some water piping, it has apparently been examined by numerous researchers as explained in site at

http://skepdic.com/dowsing.html

(including some financed with big bucks in Europe) and even at least one apparently in a research project sponsored by National Science Foundation under Grant BNS 93-13038 discussed at

http://www.csicop.org/si/9901/dowsing.html

. In another site, it was reported there have apparently been some "disastrous" occurrences when such means of locating were employed.
The results appear very contradictory and as explained by the NSF researcher et al accessible from the latter site frankly leave me some skeptical. While I guess I would not claim any particular witcher could not locate a particular pipe, I personally would not attempt to locate mains for any critical construction purpose with such methods, until such methods and the locator are approved (or proven?) by a proper authority.

 

[mflam]

Thanks, everyone for some terrific information. We elected to shut down one line and run around and check sill cocks. Inefficient but practically foolproof.
I had tried divining before but read about some refinements and may try it again when I have more time.

 

[semo]

Dicksewerrat,

I've "witched" lines with extremely limited success and seen many contractors use this method with pretty good success on metal and plastic lines.

You mention the wands turning the other way. The first time I saw this the contractor showed me that he could turn the wands in or out by the way he held his hands together. By gripping a rod in each hand and holding his hands together by his palms (thumbs side by side), the rods went one way. If he held his knuckles together (thumbs pointing end to end)the wands went the other way. It did the same thing when I attempted it.

Before others blow this post out of proportion , they should remember whether they believe in "witching" or not, the above ground locate is only part of the process. For something to go wrong, the process wasn't completed. The line must also be exposed carefully to verify it is there and what it is.

 

[rconner]

I happened to notice "dowsing" is coincidentally featured today in an article from a New York newspaper that was available to me for one-time read at:

http://www.recordonline.com/archive/2005/05/05/dmdowser.htm

It appears this field has diversified a lot, now into many types of locating for all kinds of stuff (some even claim to be able to dowse/locate stuff using maps!), and there is apparently even an "organization" devoted to same!

Some of this is still some scary to me, but I guess we engineers have to keep an open mind!

 

[dicksewerrat]

I wouldn't use just 'witch wands' for a locate. This just tells you that you need more investigation before you dig. It just blows away new engineers though.

 

[btrueblood]

I spent my youth working for my Dad, who ran an excavation contracting business. We located power, sewer, and gas lines by a variety of methods, including: calling the utility company's locating service (usually not much better than dowsing), dowsing (my Dad could sorta do it, but none of us trusted it much), careful hand digging, and lastly (my favorite for entertainment value) digging hell-bent-for-leather through the line with the backhoe (usually because the owner or project manager has just assured us that the nearest line is 20 feet thataway from where we are digging).

Not mentioned in prior threads on this topic: if the utility company locator due comes out in his little yellow truck and locates their line, and you move 8, 10, 20 feet or whatever away, start digging and cut their line, who is liable for the outage and repair? You guessed right if you said "I am". Even if you cut the line, and it's 20 feet off of their as-built drawing and/or surveyed right-of-way, you are still liable (this is in the really fine print on their convenants).

 

[hydrae]

Btureblood

Some state have locate laws that pass responsibility for the repair and any damages onto the utility when mis-located! Part of the law requires contacting the one call locate center and following the rules, I have found backing up the paint and flag markings with photos of the marks to prove the 'we said, they said;' issues is a must.

Hydrae