Graham Sustainability Institute

How Can I Find Out If I Have a Lead Service Line?

Tuesday, November 3, 2020

Republished with permission from NRDC

For more information, visit graham.umich.edu/project/revised-lead-and-copper-rule


From Flint, Michigan to Newark, New Jersey and straight to Washington, DC drinking water crises have demonstrated that lead service lines are an invisible public health threat that allow lead to leach into drinking water. When water contacts a surface, some of that material will dissolve in the water. When that surface is a lead pipe, some of the lead dissolves into the water even when corrosion control treatment is used. The Centers for Disease Control and Prevention (CDC), public health organizations, and medical associations agree that there is no safe level of lead. This means lead service lines, small diameter pipes that deliver water to older homes like a solid lead straw, are an ongoing risk of lead exposure. Most of our household plumbing contains some amount of lead, whether in faucets, fittings, lead solder, or lead pipes, but lead service lines present the largest source and risk of lead in drinking water.

Unfortunately, many water systems do not have accurate information on the service line materials used at individual homes. This blog describes strategies water systems and individuals can use to identify whether they have a lead service line delivering water to their home. This is presented from the perspective of a resident identifying their own service line; a water utility developing a service line inventory should take a more systematic approach but would still use similar techniques.

It is good to know what the service line to your house is made of, even if it’s not made of lead. This helps you to plan for future repairs, and you will already know the material your water travels through if new concerns arise regarding other pipe materials in the future. Typical service line materials include lead, copper, galvanized steel, and plastic.

Water service lines are small pipes that connect water mains (large pipes that typically run under or parallel to the street) to a water customer’s property, as shown in the figure below. From the late 1800s and throughout much of the 20th Century—and in some cities as late as the mid-1980’s—it was common for service lines to be made from lead pipe. Unfortunately, a lot of those are still in place today. The installation of new lead service lines was prohibited in 1986, and the ban became effective in 1988. To date, there have been no national requirements to remove lead lines that were already installed and estimates indicate there may be 6.5 to 10 million lead service lines still delivering water.[1]

To figure out if your home might have a lead service line, it helps if you know a few dates:

  • The year your house was built,
  • The year your house or property first got water service, and
  • The year your house was renovated or a new house was built on a property that already had water service.

Most tax records, real estate listings, and/or building permits include the year or approximate year that a house was built and/or renovated. The year of first water service is typically the same year the original house was built, but some communities may have used private wells prior to connecting to a public water system. If this information exists, it is most likely to be available from previous homeowners or the water utility.


Click to enlarge.

If your home was built after 1988 with a new water connection, you can be confident that you do not have a lead service line. If your house or property first got water service before 1988, there is a chance you may have a lead service line, even if your home was remodeled or replaced later.

At the same time, many homes built before 1988 do not have lead service lines. Lead service lines began to be phased out in many communities around World War II because the lead supply was diverted for weapons. This is where determining your service line material can get tricky—every community is different. Some communities never used lead lines at all. Some communities, like Chicago, installed lead service lines until the ban on lead service lines in the mid-1980’s.

Service lines can consist of many different parts and materials, and your water system may not know the material of every portion of the service line. A service line may have up to four distinct portions, as shown in the figure above, and any one portion, or all portions, can be made of lead.

  1. The section from the water main in the street to the curb stop near the property line is often considered the “public side” and is typically owned by the city. The corporation stop and the curb stop are both valves that can be used to stop the flow of water to your house.
  2. In some cases, there is a small “gooseneck” or “pigtail” that bends to connect the service line to the water main. It’s often made of lead.
  3. The section from the curb stop to the house typically runs on private property and is sometimes called the “private side.” The ownership of service lines may differ from city to city. Sometimes water utilities will assert that this portion of the service line is privately owned (perhaps because the utility may be required to pay to replace it if they own it), but the ownership of the service line in many cities is unclear and requires careful investigation.
  4. The only portion of a service line that can be identified without digging up the pipe is the short piece inside the house that runs to the meter or the main shutoff valve inside the house. The portion inside the house can be a different material than the buried portions of the service line.

If you know for certain that the entire lead service line was replaced at your house and you know the material that was used to replace it, there is no need to walk through the steps in this blog. In this case, call your water system to make sure their records are up to date for your home.

The first step for identifying your service line material is to call your water system to ask what materials your water service line is made of. If your water system says that you have a lead service line, assume they are correct and treat your water as if you have a lead service line even if you can’t see lead inside your house as described below. Some water systems may consider lead goosenecks or pigtails to be separate from the rest of the service line. When you are on the phone, ask your water system if lead goosenecks or pigtails were ever used and during which years they were common. If this information is not clearly documented at the water system, a conversation with an experienced maintenance and repair utility worker can reveal important information about the water system in general and your home in particular.

Other answers the water system may provide about your service line might include:

  • The service line does not contain any lead,
  • The service line is made of [copper, galvanized steel, plastic], or
  • We do not have records of your service line material.

Detroit Water and Sewerage Department, with test area circledClick to enlarge.

No matter what they answer, ask your water system to describe their confidence in their service line inventory data. You may also want to call your state’s drinking water program to ask whether they know if your water system has an accurate service line inventory. Some states have required service line inventories like Michigan, Illinois, and California. Others have not. Even if the water system has records indicating a non-lead pipe at your house, it will give you peace of mind to make a few more basic checks to verify their information.

As you walk through the steps described here, if you identify any portion of your service line that is made of lead, there is no need to continue investigating because you have a lead service line. In this case you should take necessary precautions and plan to replace the line.

The next step is to check the material of your service line where it enters your home. A service line for a home usually enters a home in the basement or crawl space, and is commonly located just prior to the shut off valve. The water meter may be in the same location, but in some areas the water meters are outside the home. The picture below depicts a typical configuration for service lines and meters, although the orientation of the pipes may be different depending on the home.

Detroit Water and Sewerage DepartmentClick to enlarge.

Locate where the service line comes into your house near the main shutoff valve. Look for the test area between the wall or the floor and the shutoff valve, shown circled in the picture above. In some locations the service line may not be visible at all, like in this picture:

If you can’t see the service line, you have to rely on water utility records or dig it up to confirm the material.

If you can see the test area, gently scratch the surface of the pipe with a coin. If the pipe is soft and easily scraped, silver, and a magnet doesn’t stick, it is lead. It may have a bulb in the pipe near the shutoff valve that looks like a snake that swallowed an egg.

If you find a lead line entering your home, you have a lead service line. Check here for steps you should take to reduce your risk of lead exposure through drinking water. Take a picture of your service line and send it to your water system so they can verify your results, update their records as necessary, and add you to their lead service line replacement program.

If your home had water service before 1988 and you do not find a lead service line visible in your home, you still have several steps to take to verify your service line. The next step is to identify the non-lead material inside your home:

  1. Does a magnet stick? If yes, this portion of the service line is galvanized steel.
  2. If it is copper colored and a magnet doesn’t stick, this portion of the service line is copper.
  3. If the pipe is white or grey and the piping is joined with a clamp, screw or glue, this portion of the service line is plastic.
  4. Sometimes the pipe is not easily identified because it is painted or wrapped. Sometimes the shutoff valve is actually at the floor or the wall and no portion of service line is visible at all inside the house.

Even though you do not have lead inside the house, there is still a possibility that you have a lead service line buried between your home and the water main. If you live in an older house and you see freshly patched flooring around your service line, there is a possibility the service line was recently replaced. There is always a chance that it was only replaced inside the house, making it important to check with the water utility or building permits for your house.

The most reliable way to identify the buried service line material is to reveal the pipe material by digging, working with your water system to safely verify the pipe material. Unfortunately, remote sensing equipment that is capable of identifying lead service lines has not been developed yet. To be the most comprehensive, you should excavate at the curb stop to reveal both the public and the private side of the service line, since these can be made of different materials. Many different terms have been used for this process, including excavation, potholing, and hydrovacing. These are all variations on digging up the pipe at the curb stop to visually identify the service line material.

As mentioned previously, you can stop walking through these identification steps as soon you confirm the presence of a lead service line. If you don’t see a lead line you should work with the water system to reveal a larger section of pipe. The larger the section of pipe that is revealed, the more confident you can be that the materials of the entire service line have been identified. If a lead service line was partially replaced on the public side only at a prior time, the connection of the old lead service line to the new material can be as far as 2 feet away from the curb stop on the private side. Replacing partial lead service lines is a common water industry practice, especially if the water main in front of your house has been replaced in the last 30 years.

It is more challenging to excavate at the water main to check for a lead gooseneck or pigtail (see the picture above) because this may involve tearing up pavement. Ideally, your first conversation with the water system provided information on the likelihood of a lead gooseneck or pigtail at your home.

To learn about water sampling strategies for identifying lead service lines, click here.

Unfortunately, excellent records management at your water system or excavation are the only ways to get definitive answers on the buried service line material at your home if you haven’t already confirmed a lead service line inside your home.

Given the challenges with service line identification, it is most efficient for water systems to develop their own documented and verified service line inventories so they can tell their customers that do and do not have lead service lines, rather than having each customer investigate on their own. If you learn through this process that your water system does not have a verified service line inventory, ask them to develop an inventory and notify residents of their service line materials. Potential future changes to the federal Lead and Copper Rule may include new requirements for service line inventories.


Elin Betanzo is the founder of Safe Water Engineering LLC, a small consulting firm working to improve access to safe drinking water through engineering and policy consulting building on 20 years of drinking water experience. In August of 2015, Elin played a critical role in uncovering the Flint Water Crisis by encouraging pediatrician Dr. Mona Hanna-Attisha to conduct a study that discovered elevated lead levels in children living in Flint, Michigan.


1. Environmental Protection Agency, Lead and Copper Rule Revisions White Paper (Washington, DC: October 2016)