Water line to the street- advice?

Question

The water pressure on one side of a duplex is not-so-great. The plumber thinks the issue is with the water line to the house (built in 1935). I'm concerned that it might be tree roots growing into the pipe. Any advice on repairs (rotorooter?), or will I just need to budget to replace?

Mike Wood · Answer

@Amanda G. On the water supply side, its highly unlikely its tree roots. Likely corrosion built up in the pipe causing the restriction. If you have two water meters, it could be the pipe from the meter to the house, if you only have one water meter, the problem is more likely at the house where the piping splits into each unit.If the pipes are galvanized steel, and old, you definitely have corrosion and scale build up in the pipes causing restriction. If the problem is isolated to one fixture (sink, shower or toilet), it could be a local issue that could be fixed local to the fixture, but that is likely a short term fix as the other fixtures will continue to have low pressure as corrosion and scale build up.

Mike Wood · Answer

@Amanda G. Risking? If you are asking if the replacement of the line from the meter to house now will damage the other pipes, I would not believe so. While it is possible the increase pressure could cause some leaks if the pipes are rusted, its not likely if your not seeing problems currently. My comment is that the problem is likely everywhere in the pipes, its just the main line is causing the most pressure loss. So eventually, the build up will continue and you may start to see other low pressure problems. My first house had galvanized piping and on one of the faucets the hot water side was so blocked up that the water would barely trickle out. When we removed that pipe (during a repipe), a piece that was less than 6" long was so blocked, that no light could be seen thru it.If you do a complete repipe, it will be cheaper to do it at one time, than to just replace the main supply line, then later repipe the rest of the house.

Dennis Vo · Answer

@Amanda, first turn off your water meter at the city side, then disconnect your side lateral line that is connected to the water meter. Then turn the water meter on slowly at the city side, mainly to check the pressure from the street to your house. Most likely, this pressure should be strong. If it's weak, then call the city to check for you. If the flow is good, reconnect your lateral line to the water meter, and move on to the next step. Now, check your water flow (presure) at the closet hosebibb which is nearest to your water meter. If the water doesn't flow well, then the plug is between your meter and the hosebibb. But if the pressure is still strong then move on to the nearest water output (faucet, toilet, etc.). Keep on testing at incremental sections... until you encounter the water flow dropping.@Mike Wood is right about corrosion... especially with galvanized pipe. Since your house was built in 1930, built-up calcium is another major problem.If you are going to replace your water supply lines, you may want to consider "pex piping". The technology is really good now, and the material and installation are much less than copper.Good luck

Dick Rosen · Answer

I don't think they send camera's or roto rooters in water lines, only sewer lines. Your plumber is probably right but I'd get 1 or 2 more opinions from other plumbers, that is an expensive repair.

Amanda G. · Answer

@Mike Wood, am I risking the rest of the pipes if I don't do the supply line quickly?

Mike Wood · Answer

@Amanda G. Since you have separate meters, its likely the line going from the meter to the house, which is underground. If your house is raised (crawlspace) its an easier job, but still labor intensive as the line would have to be dug up and replaced. There really is not any good way of 'cleaning out supply lines'. Shop the job, as some plumbers might not want the work due to the amount of manual digging required, and their prices would be high. Also, if the main line is bad, its likely a matter of time until the other pipes start to give you issues. Might be a good idea to think about a repipe on that unit. But that will be thousands, so your property might not be able to afford it.

Jon Holdman · Answer

I don't think they have cameras small enough to get through a supply line. Those are usually only 3/4", unlikely to be over 1". Yeah, you need to plan to replace it. If this is 80 year old galvanized pipe you're lucky you've not had the opposite problem - leaking.The water company may be able to come test the pressure at the meter. Typically your responsibility if from the meter to the house, and their responsibility is from the meter back. If you get a pressure reading at the meter, and then inside the house while the water is flowing, you may be able to determine if its the supply line. Better would be a flow test. The water company tests the flow rate at the meter. Then you test somewhere on your side. This is pretty easy if you can see the meter display. When I had this done, the water company shut off the water and put a spigot on my side of the outlet. They took pressure there, then turned it open wide and measured (with the meter) the output for one minute. That gives you gallons per minute. Then, after they hook it back up, you do the same thing by opening a hose bib on the house and running it for a minute. The closer you can get to the house end of the line the better.

Amanda G. · Answer

@Aaron Klatt, thanks. It is pretty clearly on my property, not the street. (I wish!)

Amanda G. · Answer

@Mike Wood, they have separate water lines. The water pressure is mostly noticeable when you flush the toilet and the pressure in the rest of the apartment drops. The plumber said it wasn't the toilet. Any repair for the pipe corrosion, or am I looking at needing to replace it?

Aaron K. · Answer

If you sent a camera down the pipe you should be able to tell if that is indeed the issue, if the problem is on city property (the street) you may be able to contact them and see if they can do anything.