How to locate Sewer

**blue34** · January 9th, 2009, 12:07 PM

Anyone have experience locating sewer? I am wondering how you can locate PVC pipe, clay, etc, basically lines that are not metallic.

**Inverted** · January 9th, 2009, 02:57 PM

You can't locate sewer. You just line up the sewer covers to mark the gravity serwer main( they are pretty straight ) and line up the clean out at the residences. I good set of print helps, but most of the time it's an eye ball locate. Contractors are not too worried about those because they don't dig that deep. If it's at a residence, they have to pot hole it before a bore(not you_don't bust your ass). You just make a more or less mark on sewers.

You can locate sewer, but you need ground penetrating radar for those non conductive pipes. The radar can pick up round shapes and an experienced locator(like me) can understand those squigly lines on the screen. If you can't locate it, just put a note and call your contractors, and supers and blah blah blah. Don't make a big deal about it.

**TheCableVine** · January 9th, 2009, 03:52 PM

Originally Posted by blue34

Anyone have experience locating sewer? I am wondering how you can locate PVC pipe, clay, etc, basically lines that are not metallic.

The best way, if you can access them, is to put a sonde in the pipe. Or, fish tape will work too. Any kind of metal cable that will go through the pipe. Then, hook up to it and locate away. As you reach the end of the tape/cable your signal will diminish down to nothing. if it is the sewer you are only worried about then what inverter said.

**GWJ_CAS** · January 9th, 2009, 06:45 PM

Originally Posted by Inverted

You can locate sewer, but you need ground penetrating radar for those non conductive pipes. The radar can pick up round shapes and an experienced locator(like me) can understand those squigly lines on the screen.

Actually, radar does not locate "round shapes", it echoes variations in density. The specific density of the plastic or PVC pipe is significantly different from the soil in which it is buried and therefore creates an echo. The echo creates a signature on the screen that resembles a hyperbola due to the manner in which the radar signal leaves and returns to the antenna.

How much radar "experience" do you have?

**underground quester** · January 9th, 2009, 06:57 PM

As has already been stated line of sight OR Ground Penetrating radar so will not add anything there.

Your message does not state whether you have to locate sewer service to commercial or residental. If you do, be aware that not all sewer service runs straight out, sometimes it can be offset some distance. A good computer program or plan from the sewer utility might help...providing of course the plans are up to date!!!

**Inverted** · January 9th, 2009, 11:05 PM

Originally Posted by GWJ_CAS

Actually, radar does not locate "round shapes", it echoes variations in density. The specific density of the plastic or PVC pipe is significantly different from the soil in which it is buried and therefore creates an echo. The echo creates a signature on the screen that resembles a hyperbola due to the manner in which the radar signal leaves and returns to the antenna.

How much radar "experience" do you have?

Well, the screen shows a hump when I pass over a sewer main, The rounder the hump the bigger diameter is the pipe. If it is a sharp spike, it could be a thin pipe or cable.
But, yes you are right. You just explained it better than me. been doing this for 2 years when we were mapping out Essex County Utilities

**GWJ_CAS** · January 10th, 2009, 09:24 AM

Originally Posted by Inverted

Well, the screen shows a hump when I pass over a sewer main, The rounder the hump the bigger diameter is the pipe. If it is a sharp spike, it could be a thin pipe or cable.
But, yes you are right. You just explained it better than me. been doing this for 2 years when we were mapping out Essex County Utilities

Sorry, but again not completely correct. The size and shape of the "hump" depicted on the screen is affected by several things including; size of the target, soil conductivity, radar frequency, signal-sampling frequency, forward speed of the radar unit and screen resolution.

Radar is a valuable tool in the hands of a properly trained and knowledgeable technician but a dangerous instrument in the hands of the untrained, or those who think they know more than they really do.

**yahoo** · January 10th, 2009, 08:23 PM

well seems that sewer is alot harder than what i originally thought????!!!!!!

**beyond help** · January 10th, 2009, 08:44 PM

Originally Posted by yahoo

well seems that sewer is alot harder than what i originally thought????!!!!!!

I'll just take a dump and follow the smell.

**yahoo** · January 11th, 2009, 06:31 PM

hahahhahahha good one dude!!!!

**TBONE** · January 11th, 2009, 10:37 PM

In the past I have took masonry string from manhole to manhole but that took too long so I just line up the covers and look back to see how drunk I looked when i marked it cause I cant mark nothing straight

**bareclaw** · January 11th, 2009, 11:55 PM

bolt some small gauge wire(speaker wire,etc.) to a tennis ball drop in at a man hole up flow from where you need to locate and direct connect to the end of the wire, the tennis ball will float down stream for as much wire as you have attached to it.

**Inverted** · January 12th, 2009, 01:59 AM

Look cas, I know what a ground penetrating radar is ok? Used them many times and to be quite frank, they are a big waste of time and expensive way to locate. I would ping it if it had liquid inside. you guys are getting too scientific. The guy just wants a little advice. Sewer locates are 99.9% waste of time and paint. You just mark it for the sake of the customer that is paying to have his shit pipe marked. Sewer mains are in the middle of the road most of the time. I have seen them go under houses and under pools. There is no tracer wire, and you are not gonna be pulling out a 20,000 dollar ground penetrating radar and waste 2 hours trying to find a sewer main and reading all the data it puts out when they are just running cable tv lines. come on!! You look at the print(if you have one) and make a straight green line from the main in the middle of the road to the house where the clean out is. Don't make a big fuss over it. Unless it's slow in your area. The only times sewers have to be acurately found is when they arehigh pressure mains or they are doing big time road construction, and the public way can be in danger, because broken mains can cause poles and structures to cave in(it makes a cave under the road when it breaks). Then you would do all that stupid shit CJWCAS is talking about. Those machines are for acurate locates for big mains. An experienced locator like me, will not waste time with stuff like that. New guys spend hours locating a fence ticket. I do all my tickets in the morning at home. I milk the clock big time! My employer exploits me with cameras, gps devices, low pay, so I milk him like he milks me. If he treats me nice and gives me raises, I will be more loyal. I'm nothing to him but a number. That's how I feel about it. Employer wants to spend alot of money on fancy stuff, but can't give me $18 an hour? Then tells me I have to earn it? I worked three years with no damage, and all I get is a ****ing t-shirt. **** you. I'm milking you for gas and money.Fire me, do me the favor! tired of this baloney. everybody here milks the clock. We locate for money, not for fun. And who ever says they love locating, is a liar! They do it for the money. It is easier to earn money locating (because you don't do shit) than to work in a factory. that's why alot of you get addicted to having a truck, free gas, and can't let go when they call you to meet up and take your truck and keys. Done that, been there. Worked in every locating company you can think of. I even worked for CAS in New Port Richey. He was paying me $12 bucks an hour pushing that stupid lawn mower around (GPR). I said **** this and I quit.

**UULC** · January 12th, 2009, 08:40 AM

Originally Posted by bareclaw

bolt some small gauge wire(speaker wire,etc.) to a tennis ball drop in at a man hole up flow from where you need to locate and direct connect to the end of the wire, the tennis ball will float down stream for as much wire as you have attached to it.

Just remember to wear rubber gloves!!!

**Mke** · January 12th, 2009, 10:09 AM

I find the most reliable way to locate sewer lines is with a Sonde. It kinda sucks cause you have to stop every few feet or at any bends in the line but usually that will get you most of the service lines. The bigger diameter pipes you can usually "line of sight" them (manhole to manhole). As for GPR.... it really depends on antenna used and ground conditions on how deep you can search. Some service lines can be just out of sight for some of the common antenna used for looking for utilities.

The Deepest line i've seen wich was next to the front porch of a house was 14' deep.

And always stock up on rubber gloves and hand sanitizer, and your hepititis shots.

mke