Main Water Lines

What is a main water line? 

Think about how many times a day you use water in your house. When you wash your hands, pour a cup of coffee, or run your dishwasher, you probably are not thinking about how the water gets from the street to your faucet.  You have more important things to worry about. Someday, though, your home’s main water service line will need to be repaired or replaced. We know that having a plumbing problem is the last thing you want to deal with, but you’ll have less of a headache if you know what to expect.

What can cause a water line to break?

There are multiple factors that can contribute to a failing water service line. One of the most obvious causes of problems is weather. Although water service lines can break any time of year, they commonly have problems during periods of extreme temperatures when pipes expand and contract. The pipe’s material has a lot to do with how well it fares during drastic temperature changes. Older pipes are made out of materials such as iron that are less forgiving than the PEX piping being used today. One of the advantages of PEX is that it can freeze without cracking and breaking. Older pipes are also susceptible to corrosion, both inside and out.

Natural environmental causes include soil erosion, ground shifting, and tree roots. When planting trees, it is a good idea to consider where your main water service line is located and take that into consideration. Try to avoid planting over or near your water line.

Human error is another cause of broken water lines. It is always important to know where your utilities are located before you start any excavation projects, no matter how big or how small. You should always call 8-1-1 before you dig, to avoid accidents such as severing your water line with a shovel.

It helps to know what exactly we are talking about when we refer to your home’s main water service line. Whether you are on a well or city water, there is a main line connecting your water supply to your house. If you have a well, you are using groundwater that is being pumped from aquifers deep in the ground to the surface. If your water comes from a public water utility, that water has been mostly collected from surface water. Water is treated before being sent to your house, which makes it potable, meaning it is safe to drink, use for food preparation, and bathing.  Your main water line is buried underground and is only used for carrying potable water to your house. Water and sewage being taken from your house goes through a different line, called a sewage pipe.

hole in ground exposing broken water line for plumbing technician
plumbing technician repairing a broken main water line in the ground
repaired main water service line with pex pipe

This water service line broke when the customer had several trees removed. All we needed to do in this case was a spot repair. 

What are the signs that I need a water 

line repair or replacement? 

Knowing what to watch out for can save you the time and stress of trying to figure out the cause of your home’s plumbing issues. Some signs are more obvious than others and could have more than one cause. These are some of the most common signs that your water service line needs to be repaired or replaced:

Soggy patches or water pooling in your yard. This could indicate a leak in either your water service line or your sewer line. Your nose may be able to tell the difference. Either way, you need to call a plumber to fix the leak.

Rumbling sounds and other noises. These will likely be more noticeable at night or during quiet times of the day. A leak can cause vibration in the pipes, leading to strange new water sounds. This is often the first indication there is a problem.

A drop in water pressure. A sudden drop in water pressure usually indicates a leak. It could also mean that mineral deposits are restricting water flow. A plumber will be able to determine the exact cause of your low water pressure.

Discolored water.  Rust colored water means there is rust somewhere in your home’s plumbing system. It may be coming from the water heater, a pipe in the house, or the main water service line. A plumber will be able to do an inspection of your home’s plumbing and diagnose any problems. Besides replacing your home’s water service line, your plumber may also suggest repiping your home, especially if your home has galvanized pipes.  

A higher-than-usual water bill. Sometimes your first clue that you have a plumbing problem is a higher water bill than what you’re used to seeing. If your water usage habits haven’t changed but your bill has, you should investigate.

pool of muddy water in large hole in ground from broken main water line
water pooling near sidewalk around broken irrigation system

Water pooling in your yard is a clear sign that your water service line is broken. Once the leak is located, a plumber can repair the line. 

If the leak is in your irrigation system,

an irrigation professional should be able to help you. If you have a leak in your main water service line, you will need a plumber. 

How can I determine if I have a leak and where it is located?  

Several plumbing issues can cause the symptoms listed above. You’ll need to isolate the source of your problems. A plumber can help you do this, but there are things you can do to check for yourself.

Pooling Water or Squishy Ground

If water is pooling in your yard, and you don’t smell sewer gas, there are two possible causes. You have a leak in either the main water service line or in your irrigation system. Of course, if you do not have an irrigation system, the answer is clear. If you do though, you will need to determine which system has the leak so you will know whether to call a plumber or an irrigation professional.


Water Meter

In the absence of an obvious location, check your water meter. Water meters are usually located near the curb in front of your house. It will likely be housed in a box with a cast iron, concrete, or plastic lid. Be careful opening the box. Lids can be heavy and sharp. Wearing gloves is a good idea. Use a tool such as a screw driver to help pry up the lid. If the gauge has a cap, flip it up and look for an indicator such as a red triangle. If there is not an indicator, note the location of the needle. Make sure all the water in the house is turned off, including dishwashers and washing machines. Now look at the indicator. Is it moving? A rapidly spinning indicator means there is a fast leak. If it is spinning slowly, there is a slow leak. If using the needle as a reference, leave the water off for thirty minutes to an hour. Look to see if the needle has moved from its original location. If it has, there is a leak.


Search Around Your House

It is possible that the leak is not in the main water line. It may be inside your house. Think of every place in your house that uses water and look there for leaks or drips. Toilets, faucets, and underneath sinks are good place to start. Also, look around your dishwasher, washing machine, and behind your refrigerator if you have an ice maker line. Check around the base of your water heater and examine all fittings and connections for moisture. Next, examine the walls and ceiling. Are there any signs of water damage such as stains or mold? Don’t forget to also check outside for a leaking hose bibb.


If you still have not found the source of the leak, we recommend calling a leak detection company. Then your plumber can get to work making all the necessary repairs.

blue water meter lid in concrete
water spraying from leaking hose bibb

Checking your water meter can help you determine if you have a fast or slow leak.

Look inside and outside your house for leaks and drips. 

Do I need to repair or replace my main water line? 

Your plumber will help determine the best course of action based on their assessment. If overall your water line is in good condition, a spot repair may be all you need. However, if there are multiple leaks in the line or the pipe is otherwise compromised, a spot repair is just putting a band-aid on a larger problem. The costs of individual repairs add up. A replacement is often the most cost-effective, best long-term solution.

How will the main water line be replaced?

Replacing a main water line used to mean digging a trench through your yard and causing major disruption to your property’s landscaping. With directional boring, however, there is minimal digging and you will hardly be able to tell anything happened. TVP makes replacing a water service an easy process for homeowners.


First, we have your property’s utility locations marked at no cost to you, and a qualified plumbing technician will evaluate your water service needs. We will provide you with an upfront, flat rate price that includes the cost of permits, parts, labor, and warranty. When you decide to hire us for the job, we will write up a detailed contract, review it with you to make sure you are satisfied with the agreed upon upfront price and that you understand exactly what we will be doing. To reserve your date in the schedule, all we need is your signature and a one-third down payment. Next, we purchase a plumbing permit, materials, and schedule directional drilling. This trenchless technology allows us to run new PEX pipe underground from the water meter to your house. Some digging is needed near the meter box. If there are plants in the way, we will do our best to work around them or carefully remove them, but we cannot make any guarantees. We are experts when it comes to plumbing, but we are not landscapers.


The water line is replaced in less than a day. Then we schedule a plumbing inspection, usually for the next day. Once our work has passed inspection, we back-fill any holes and leave the area as clean and neat as we can. Please note, you will most likely need to hire an electrician to address electrical grounding before passing final inspection.

ditch witch machine directional drilling for new water service line from meter

Trenchless water line replacement reduces disruption to your lawn and other landscaping.

caution tape around hole in garden dug for water service line replacement

Some digging around the meter is always necessary, but we do our best to work around vegetation whenever possible. 

How can we help you?

For more information about water line repair or replacement, or to schedule a free estimate, please call us at (503) 607-7242, or send us a message.