What Is Causing My Plumbing Pipes to Vibrate?

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Comments

Bernie

Subject: Heat and noise

Hi my wood floors are warm and their is vibrations at times
Don't know if it is the hot water line or there also is a floor to ceiling forced air heating and air conditioning with coils directly under my floors (the lobby ceiling )
Any possible solutions ??
It's a real nuisance

Tina Morales

Subject: Pipes hammering when washing machine is filling with water

When my front load washing machine is filling with water there is a hammering sound that lasts for a few seconds. I have also noticed that the liquid laundry dispenser in my machine is not emptying during the rinse cycle. My laundry room is located on the lower level of an A frame home with a second bathroom located just behind the laundry room.

I hear the noise behind the sink wall in the lower level bathroom and also at the water sprout located on the outside of the home on the main floor. This area is located above the downstairs bathroom and laundry room.

I had a plumber here a few weeks ago to fix a dripping leak in my upstairs bathroom vanity. He also fixed a broken faucet in my kitchen sink.

It's weird, but this hammering noise began about a week after he made these repairs. I have no idea if this is related.

We have opened the outside faucet and allowed the water to freely flow for a bit hoping this would fix the problem. It did not. The hammering only happens when the washing machine is filling with water. No problems when flushing the toilets or using any other water source within the house.

Any ideas?

Thank you.

I

Ryan Wittcop

Subject: Water pressure causes vibrations

I have one toilet in my house (three total) where the only way I can prevent the rattling sound is to keep the water pressure low to the toilet. If I turn it up the rattling begins again. The problem is that it takes half an hour after flushing for the toilet to stop running. I have replaced the valve in the toilet and have shut down the water to the house and replaced the water after it drained. Any thoughts?

Cliff Owens from Mazzitelli & Merollo Plumbing & heating

Subject: pipe hammer, rattle, vibrations

I'm and experienced plumbing & heating master mechanic, these problems can be cause by several issues, a lot pertaining to slow leaks, fill valves, water pressure, pipes not secure enough with straps, and braces, The problem I had in my house that was making noises for a month, and when I was the one to finally hear it, i fixed it in 20 seconds by replacing my corky in the toilet tank cause it was worn out, needed to be replaced, one I replaced the corky, it stopped a 100% haven't heard it since, it can be many problems people, but definitely get a reputable plumber, cause it could be a 20 second cheap fix, or may not be, just don't let someone you don't know turn ti into a major problem! Make sure it's troubleshooted correctly, and you know and trust the plumber, or just like car mechanics, cause you don't know anything about plumbing, ten mysterious problems could appear. good luck just wanted to share my experience and advice to everyone. Most likely it's something you can fix on your own, just turn all your faucets, and valves, and check all your corkys in toilet tanks, check all toilet tank fill vales and your toilet valves that come through the floor or wall for shut off, and one of those may be the problem and need to be replaced, if not, could be inside the wall pipes not secure, strapped, and braced enough, and will require walls to be open, unless the pipe is already exposed underneath the house or atic or in a mechnical room etc. Could be the water pressure coming in from the street or well pump. Help I could help and save everyone from spending too much money on the plumber who sells everyone a dream.

Gary

Subject: Rattling pipes

We hear rattling pipes from the attic only in the middle of the night. No water is being used. We have air conditioner plumbing up there. We have solar on a tile roof.

Tim

Subject: Water line hammering

I installed a new water heater about 6 months ago and have had a consistent water hammering (mild) that occurs every 10 minutes. I will hear about 25-30 quick tap sounds and then it goes away. I have tried shutting water off, getting air out of lines but no good. I talked with the plumber that had installed it and I was concerned maybe there was a plastic cap stuck somewhere but he said no he pulled out and he couldn't answer why? Thank you for your assistance

Cheryl huey

Subject: Vibrating Pipes under house

There is a vibration under my bedroom floor which I can feel when sitting on my couch and less so when standing on my kitchen floor. Could a toilet that is not filling up on its own without adjusting the lever in the tank be the cause if not what could it be I am scared to call a plumber as I have been ripped off before and scared not to. Or could it be my air conditioning system as it vibrates and makes noise when it comes on could thus have effected pipes below my house? Any suggestions.

Katy Degenhardt

Subject: Loud pipes

I have the same problem. I looked at the picture posted exposing the pipes...and I noticed a few sharkbite fittings. I also have one and did not have this issue until AFTER I installed it. I am thinking in some cases it is the sharkbite...

Evelyn

Subject: outside faucet

I have the same issue when I turn on my outdoor faucet to water. If I don't turn the handle all the way up the pipes shake all thru the house and we get this high pitched whistling. My husband says he tried changing the seal on the faucet and that seems to work for a while, but the shaking and whistling returns after a while. Any suggestions?

Keith Mayfield

Subject: rattling pipes in the wall

We've been here for ab out 18 years in house that is over 30 years old. About 6 months ago the pipe(s) started to make noise throughout the day. It didn't matter if the sink, shower or toilet was being used; it just did rattle just about any time. It appears to be a noise behind the sink vanity on one side of the wall and wallpaper that my wife doesn't want to disturb is on the other side of the wall. I was wondering if I should go under the sink and remove the back wall from the vanity allowing me space that might be where the noise originated. Any suggestions?

James

Subject: rattling pipes

I replaced some old copper pipes and over looked the fact that it had air chambers near the center of the home between the supply and on the hot water side. Removing these chambers caused the vibrating. Once put back I had vibrating initially but once I got all the air out of the main line not to include the air chambers problem solved. Over time the fill with water. I actually installed longer chambers. All you need is a pipe with a cap and a T fitting. Point the cap straight up and solder in place. Mine are about 11 inches long because that was all the space I had to the floor in the crawl space. Just clean your parts thoroughly, use flux and a blow torch with a little solder and you have an air chamber. Do it to both hot and cold. Some people put the at the hot water heater. It allows cushion for the water to compress. Good luck.

bob butta

Subject: plumbingpipe rattling or rumbling when toilet flush

thanks for all of this info....it gives me something to think about....(seems as if we had a clogged toilet for a year...(always needing to use the plunger)...we had a basement toilet installed, and the original toilet was still clogged...my wife used draino int to bathtub and several different times, and finnaly the toilet flushes perfectly 94 percent ot the time...however---> this is when the noise started!!..sometimes I think we being dragged down the street orsomething!!...??..heh...very strange!...but the new basement toilet is rarely clogged(although, it did clog a few times)...but doesNOT cause any noise in the pipes.......

Brittany Richardson

Subject: pipes

Through out the day ib hearb vibrating noises in my home sounds like it's coming from my basement and it happens even when I'm not using any water in the house it's kinda scary at night when I'm sleeping.. I want to know what the problem is so that I can get it fixed because this is my first home that I've owned for two years and I don't need any major issues if I don't have any already ... help! Please any one

Exxelle

Subject: Pipes

Did you receive an answer??
I am in my new home, of about 2 weeks now &, I am having what seems to be the same problem as you have. Tonite is the first time that I have heard the sounds at least 30 minutes to an hour after I've used the toilet. Usually it's shortly after. To say the least, I am a bit concerned. If you found your solution I would love to hear it.

Thanks

Lafayette LA

Subject: Might also be due to loose washer in the faucet

I was experiencing rattling noise when turning on hot water in the tub. I read through all of the suggestions above, and on similar lists elsewhere. Then I happen to ask my father-in-law, a plumber since he was 17. Right off he says, it's the washer. The washer is loose. I changed the washer, and also the screw (which appeared to be loose). The problem was gone.

Mike Hawthorne

Subject: Loose screw on faucet valve stem

Had the same problem. The cold water faucet in the lower bathroom sink was leaking so I replaced the seat and stem. Right after that, the pipes were vibrating madly whenever the water was turned on to that faucet, so much so that the lights above the mirror were flickering.

After reading your suggestion, I turned off the water to the house, opened the highest and lowest faucets in the house to drain the pipes, took out the bathroom faucet stem and looked at it. The washer was fine (it was brand new) but sure enough, the washer screw somehow had got loosened. I tightened it and reinstalled the stem. I closed the lowest faucet (the one I was working on), and turned the water back on, allowing water to flow back up to the highest faucet which started spurting. I opened the remaining faucets to get rid of any other air spurting and then closed all faucets. I tested the lower faucet in the bathroom and the noise and vibration was gone! Thanks for the tip!

Jessica

Subject: I just bought a home and

I just bought a home and after living here for only two weeks my girls were in the tub and a sudden hammering or banging noise started coming from the walls or basement I'm not sure but this hasn't happened the whole time what could it be?

Olga lorenz

Subject: Hammering on wall with vibration .

Hello. We just build a new 2 story house about 1 1/2 years ago. Everytime I turn on water there is loud hammering sounds with vibration behind wall on 1 st and second floor. We told the plumbmer that did the pipes and he came and drained all water and is still making the sound. I Beleive even louder. What should I do.

John J.

Subject: Noisy pipe behind the wall

When the cold water is turn on, a creaking sound can be heard through the wall.The sound is pretty random when the faucet first turn on and the sound will continue even after the faucet was turned off. It is not hammering affect sound but more of a single creaking sound at different time length between the creaking sound. I hope someone may have encountered this and share the experience. Thank you much! John J.

John Tompkins

Subject: toilet vibration

First of all this is not a "hammer" issue, it is a "vibration" issue, which are 2 totally different problems. While this could potentially be a Pressure Reducing Valve problem, I doubt it. I am guessing that you have older toilets in your home that have old "ballcock" style fill valves (floating ball on a brass rod that causes the fill valve to close) installed in the tanks. One or more, but probably just one of these ballcocks in your 4 toilets is not shutting off positively and is allowing a tiny amount of water to flow through just enough to cause a vibration in your copper pipes. Think about the vibration that is caused when you allow air to escape from a balloon with the end pinched off. One faulty ballcock can cause this problem even though it occurs when you are flushing other toilets or turning on other faucets. The pressure drop causes the vibration to re-occur from that single valve. Find the problem by carefully watching the ballcock in each tank as it completes it's fill cycle, as this is when the vibration is likely to occur. Look at all four toilets until you find the one that is causing the problem, and replace it or all of you old fill valves with a new Fluidmaster fill valve or even a new ballcock style fill valve. It is also a good time to install new flappers in your tanks as well.

Liz Downey

Subject: Toilet vibration

God bless you, John Tompkins. You solved my problem. And I thought I was going to have to pay a plumber hundreds! Thank you!

Miguel Acevedo

Subject: Toilet & Faucet Vibration Gone!

Hi John!

It you ever read this since your post is almost two years old, THANKS for you posing!!!

The problem I initially having was vibration on the cold water side and no other indication; thankfully no hammering. As it progressed, that same cold water line that fed the sink and also feeds the toilet, started to vibrate when we flushed. Strangely enough the vibration would go away when I turn on the cold water in the shower. I was getting ready to crawl on my crawl space to see what valve is upstream of them both and replace it.

Then, I bumped onto you post so I went and open the toilet's water tank and observed the ballcock fill valve to see what it did when I flushed. I also manipulated it by pressing up and down to see if any vibration occurred. Sure enough it did so I went to ACE hardware (its the closest store to my house) and I bought a Korky Quiet Fill valve. Came home, installed it, and it worked like magic. I also replaced the flapper, updated the toilet handle and switched the supply line from a compression style to a regular one.

Overall this would have been a $10 if I was to just replace the fill valve, but I spent about $45 to replace everything I mentioned on that toilet. I also replace the fill valve and flapper on my other toilet which also had the ballcock style fill valve and the flapper for an additional $15. So, $60 in parts and lots of sweat. Time wise, took me longer to drive to ACE (twice...) than to swap the valves.

Its amazing how something so simple could ruin your day and your pocket chasing a simple vibration...

Thanks for your post John Tompkins!

Paul Hood

Subject: Toilet Vibration

Wow! Just went to one of my toilets and slightly pulled on the chain/rod that opens the flapper valve to let a little tiny bit of water out so the ballcock would go down and let water in. Did this intermittently a few times and totally recreated the vibration!! Then I did it again and while the vibration was happening I opened the flapper much wider and IMMEDIATELY the vibration stopped. Problem solved after about a year and me contemplating purchasing a new sump pump for the basement because "that just had to be it" or even a new well pump. And lately I was able to run to the basement while the vibration was happening and realized it was neither of those. Then I though well it must be the super expensive HVAC unit (copper line) that comes in the house. But then I was able to look out the window and see the HVAC was not even running when it happened PLUS I also realized that copper line has foam padding all around it. So that's when I started searching the Internet and found your answer. Thank you so much. I knew about water hammer, but this vibration I've never heard or heard of.

Zach Paradis Plumbing

Subject: toilet vibration

Hi, It could be many things that cause the banging of pipes. Most likely is that they have extreme water pressure. Putting in a water hammer is always good in any home . Also a expansion tank just before the water heater is always good and code in NH where I live. You can for now just ajust your shutoff valve next to the toilet and slow the fill rate of your toilet. you only need a pressure reducing valve if you have city water. .If you have a well you can ajust the pressure at the well tank.

http://www.bastplumbingandgasllc.com

Subject: vibrating pipes

I have found through all my years of experience that if you have a pressure reducing valve then 9 times out of 10 it is the problem, otherwise it is as was stated. In Arlington County Virginia they have now out lawed the valves unless you have an expansion tank above your water heater, the reason being is that not only is the home pressure reducing valve factory set to 50psi and may be adjusted to a maximum of 75psi is also a one way check valve with an arrow on the side indicating direction of water flow. If the pressure relief valve were to fail and if you have a pressure reducing valve then you are sitting on a bomb. By deleting the pressure reducing valve, the excess pressure is sent back into the street water main pressure which depending on where you live will run between 50psi & 95psi. Years ago most people ran on well pressure which is usually between 40psi & 55psi so fauct and valve manufacturers built their products to operate with the low pressure. Now they are designed to operate at full water main pressure so the pressure reducing valves are no longer needed.

Rollin

Subject: noisy pipes

it could very well be debris in a tub and shower valve... Delta, for example has a check valve assembly in their tub valve body. When you run water from a particular part of your home it will reduce pressure in other areas, when the valve you are using is shut off it quickly increases pressure back to those other areas. When the check valve assembly in the tub valve is compromised by debris it will now 'flutter', causing pockets of air to 'hammer' inside the tub valve body, thus causing your noise.

Depress your toilet flush handle slightly, allowing a small amount of water to drop from the tank into the bowl until your fill valves starts to run. This will save a bit of water and reduce the waiting time for the fill valve to shut off. Listen near your tub valve for a rapid, hammer... it will be very obvious if this is the problem. In my experience this 'has' been the cause of a majority of hammering issues that I've been presented.

Many brands of valves are easily disassembled and cleaned, some require valve cartridge replacement. Determine the manufacturer of your valve, contact their customer support department and discuss your options... it could also very well be that your valve is under a limited warranty that will provide a free replacement part.

Kevin Thomas

Subject: Water Hammer

Hello,
Just wanted to add to Angie's response concerning water hammer. Being an experienced plumber myself, she is right on the money with her diagnosis. I would be more inclined to think it is most likely due to no type of an arrestor being installed on the piping from installation. One thing that may help, if not already installed is adding an expansion tank at the water heater. Years ago they were very seldom installed but now it has been adapted as plumbing code in most counties. An expansion tank is primarily designed to avoid damage to the dank of the water heater but have found that it too can assist with pipe rattling issues throughout the house. The expansion tank needs to be sized based on the gallon capacity of the water heater and installed on the cold water line no closer than 18" from the inlet to the water heater. Given it being installed on the cold water line it also assist with absorbing the sudden shock on the related piping when a valve is closed to quickly.
Hope this information was helpful.

greg wilson

Subject: vibrating pipes

all that person has to do is find a section of pipe that is as close to the vibration as possible that is accessible and install a shock absorber on that line.a shock absorber is a mechanical device that has a dedicated air chamber in the top of it,when the toilet or faucet shuts off quickly the water hammer is absorbed into the shock absorber thereby stopping the vibrating pipes.you can also use a length of pipe about a foot long with a cap on the end of it in place of a shock absorber,when you install this piece of pipe and turn water back on,there will be an air chamber in the top of this pipe,thereby making it a shock absorber,and each time the water is drained down more air will be in the pipe.

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?

First - NOT full septic tank - if that was the case you would be getting backup of sewage into the lowest drains in the house, and possible very slow flushing or refusal to drain out of the bowl - the opposite of your case.

Second - I assume you are the owner. If a renter or on a lease, this type of problem may be the responsibility of your landlord, depending on the terms of your lease or rental agreement.

OK - two possible situations here - low water in BOWL, or low water in TANK. I am assuming your toilet flushes OK, with adequate water to clean out the bowl, and that it is a typical type toilet with a tank sitting on the back of the bowl. If this is not the case and it is a designer toilet or looks like those at public restrooms (no tank), then the BOWL answers still apply if it is initially refilling OK, but if not enough refill water coming in at all then call a plumber.

First, low water in the toilet BOWL case. If the water in the toilet BOWL is low after flushing, I see four likely causes, in order of most likelihood -

1) the fill valve is not putting enough water into the toilet bowl. If you take the top off the tank, you will see a small hose (typically black plastic) coming from the fill valve (a vertical mechanism, usually at left side of tank, that the incoming water tube or flex hose connects to the bottom of on the bottom side of the tank). While the tank is refilling after a flush, a steady but not large flow of water flows through this fill tube and down into a vertical pipe or tube (usually brass or plastic and about 3/4 inch diameter, which stands almost full height of tank). The small tube puts water into this pipe, from where it flows into and refills the toilet bowl. This is also the overflow tube, which keeps the tank from overflowing if the fill valve fails to shut off. If the fill valve has a problem or the fill tube has a blockage, it may not be letting enough water into the bowl. Also, check the tube is actually pointed down into the overflow tube - if the clip came loose, rusted away or broke, then it may just be filling the toilet tank rather than the bowl. Check that a steady flow (will not be a real foreceful jet) of water is flowing out of this tube into the overflow pipe while the toilet tank is refilling. You should also see the bowl filling up at this time. If it come in but does not fill high enough because it does not run long enough, some fill valves have an adjustment - check fill valve manufacturer website for instructions. Others just have to be replaced - doable if you are handy at home repairs (see web videos on how to do it), or call a plumber for probably about $150-200 to replace fill valve (have him replace the flapper valve at same time if you get this done).

2) there is something like a rag or string caught in the trap (the waste passage within the toilet body itself) which is slowly wicking the bowl water down the drain - would be solved by a good snaking. If this is the case, the bowl will fill fully after flushing, but then slowly (typically many minutes to hours) drain down to just filling the start of the oval or round drain passageway where the waste passage starts to curve up into the toilet body.

3) blocked sewer vent pipe (which vents sewer gas and lets air into the sewer system so when you flush the traps in drains and toilets and such do not get sucked dry by the vacumn caused by the exiting flow. If this is the problem, then several drains in your house may have the same problem, or drain slowly. When you flush, the water will drain totally down the pipe and almost all the water in the bowl and trap will go down the drain too, typically with a gurgling sound for a few seconds at the end as the air seal is broken in the trap, then a small amount of water will flow back from the trap into the bowl, leaving you with water in the entrance curve to the trap but nowhere near normal height in the bowl - maybe not even enough to fill the entrance of the drain passage.

4) a crack in the toilet, letting water gradually leak out of the bowl onto the floor or into the subfloor. If this has been going on for long at all you should see water on the floor, or water coming out in the ceiling downstairs, or in the basement or crawl space under the toilet.

Case 2 - the problem is low water in the toilet TANK - since this is a sudden problem, two likely causes:

1)  the float arm has corroded or the float setting has moved. Look in tank for any broken part. You may have a black ball on the end of a metal or plastic arm connected to the fill valve (which is the part, normally at the left side of the tank, that the flexible or copper tubing comes into at the bottom of the tank), or it may be a sliding cylindrical float that slides up and down on the fill valve (typically all plastic) - see if it is broken or loose or alll corroded up (for the arm type). When you flush, this float hangs down (if lever type) or slides down the fill valve (cylinder type), opening the fill valve so fresh water comes in to fill the tank and bowl. As the tank fills it lifts this float, till at the proper elevation the bouyancy of the float shuts off the fill valve. If the setting on this float has changed then it will either cause the toilet to "run" continually because it is trying to overfill the tank (float shuts off at too high a level, so water is continuously flowing down into the overflow tube and into the bowl); or it will shut off too soon, causing only a partial tank fill. There are adjustments to adjust the float shutoff setting - typically an adjustment xxxx on the arm-type, and a slider stop clip on a small rod for the sliding type. See web videos on how to adjust this, or call a plumber.

2) your flapper valve (in bottom of tank, the part a chain or cord or rod connects to the flush handle, which opens it when you flush the toilet, leaks. If it leaks AND the fill valve is working, the tank level drops till the fill valve opens, then the tank refills. This repeats at intervals, with the tank refilling periodically even though it has not been flushed. May need new flapper valve or just a good wiping of the sealing surface to remove grit that is causin it to leak. If this is the problem you will have a slight flow of water into the bowl continually, and will probably see a slight ripple in the toilet bowl.

3) water is leaking out of the fittings or bolt holes on the bottom of the tank. If this is happening enough to make you notice low takn water level, the tank will refill periodically the same as if the flapper valve is leaking, plus you will have water on the floor and dripping off the bottom of the tank.

 

Fill valve and flapper valves each cost around $15 if you do it yourself (you can buy just replacement flapper for less if that is the problem and the matching seal is good, but that is rarely the case). A plumber call to replace both probably $150-200, ASSUMING your water shutoff valve (at the wall, under the tank, with a flex or copper tube coming fromit up to the toilet tank) will work.. If it will not shut off the flow of water, then add another $50-150 to replace that, depending on how it is plumbed and whether he has to cut into the wall to replace it (rarely required). If you do go and have a plumber do it, have both the fill valve and flapper valve (and flush handle, if aluminum or brass and corroded) replaced at the same time, as all tend to go out with age - every 10 years or so. You don't want to have to call the plumber to replace another part in just a year or two.

?

From the sounds of it, you have a clog between the floor drain and the connection to the city sewer (unless you have a septic tank).  The lower flow rates of sinks / showers / dishwashers probable don't cause a backup like the washing machine does.  A couple of suggestions.

1.  Snake the drain line with a spade tip snake, twisting the snake as you advance it.  This should clear the partial blockage.

 2.  If feasable, have your washing machine discharge into a utility sink and put a strainer on the drain to catch the clothing fibre (fibres and grease from the sink probably made the clog in the first place not to mention a garbage disposal).

3.  Replace your floor drain with one that has a backflow preventer (looks like there is a ping pong ball in it).

 Good Luck

?
It is not uncommon for a plumber to have to go get the parts necessary to repair and complete the job.  It is very hard to determine what the problem is over the phone and it is not until the repair process begins that the parts needed to resolve the problem is discovered.  It may also depend on if the plumber is using hourly rates or per job rates.  I would hope the time to get the parts would be minimal and the charge would be as well!
?

You have not said how old your house is, what normal water line life in your area is, whether it is leaking under the foundation or under the yard, etc. Cost depends a great deal on length of run, depth to dig to get below frost line, whether excavation will be through trees or other obstructions or open area, whether ground along route is too steep for a backhoe to work on, etc.

The first thing you really need to figure out is whether this is a spot repair issue, or a total line replacement issue. Your plumber should be able to help with that determination.  Very general rule of thumb - very old line from before 80's, if galvanized pipe, could be at its practical life and be ready for total replacement. Copper line generally last about 50-70 years UNLESS in a corrosive soil environment or if it has groundwater flowing actively past it, then can be 20-30 years. Plastic lines from the 60's to 80's vary a lot - from as little as 10 years to 50 plus dependingon brand. Plastic lines (PVC, HDPE, PE) from the 80's and later are expected to last 50-100 years - most have not failed yet, so no good handle on how long they will last.

An above-ground or under the slab line a plumber will do. Buried line outside he generally subcontracts to an excavator to dig and backfill the line, or asks you to get the excavation done.

 

If section needing replacement is under your floor slab or foundation, then a full replacement can be many thousands of $ depending on how many linear feet, and if interior flooring will have to be replaced or if you are on a bare concrete slab or bringing the new line in above-ground once you get through the foundation. A simple one-spot buried pipe repair (based on acoustic locating and precisely measuring the location of the problem) can be as little as $400 but probably more often $1000 or so - more if poor access like under a slab underneath stairs.

If the runs to be replaced are exposed in a crawl space or basement than it can run as little as $20/LF (probably $400 minimum job cost) to replace.

 

Outside line to the street can run from as little as $10/LF in areas where the pipe is shallow (no annual frost penetration) and in easy digging soil, to $250/LF or more if deeply buried, have to excavate through trees and heavy roots or boulders, steep topography, other utility interferences etc. Generally not more than $50/LF. Commonly, instead of digging up the old line, they select a new semi-parallel route from a good connection point for you existing interior water lines at the foundation (maybe not where it currently comes in, depoending on access) to the street main shutoff valve (called a "key box", taking a route between them that is easiest to get a backhoe into and minimizes destruction of valuable plantings or trees. A number of $50/LF is commonly tossed around as "normal" for this type of job, if exceeding 100 feet or so and digging and access conditions are normal.

If your connection is in the middle of the street rather than along your side in the yard, that can easily add $2-5,000 to the job, as the water utility usually has to do that part, and repair the street afterwards. In a major throughway street, even more because of traffic control, multi-agency permits, etc.

 

As always, find 2-3 responsible, well-recommended (Anglie's List ?) contractors, and then get bids. The route I would go is first go with your regular plumber to locate the leak (probably acoustically, by listening for the leak) and determine the scope of work needed, then if major, go for multiple bids.