How to Tell If Your Home Has a Lead Service Line: The DIY Scratch and Magnet Test

If your home was built before 1986, there’s a real chance the pipe bringing water from the street into your house is made of lead. You probably can’t see it from the outside, you can’t taste it in the water, and your water bill won’t tell you. The only way to know for certain is to look at the pipe itself, and you can do that in about five minutes with tools you already have.

The direct answer: locate the water service line where it enters your home, apply a magnet, and scratch a small area of bare pipe with a coin or key. If the magnet doesn’t stick and the scratch reveals a shiny silver color, you have a lead service line. That finding matters now more than ever, because the EPA’s Lead and Copper Rule Improvements, finalized in October 2024, require full lead service line replacement nationwide by 2034 and Pennsylvania utilities are already working through their replacement plans.

Here’s the full test, what each result means, and what your next steps should be if lead turns up.

Why Homes Built Before 1986 Are at Risk

Lead was a common material for water service lines in the United States throughout most of the twentieth century. It’s soft, workable, and durable, which made it a practical choice for plumbers at the time. The federal government banned the use of lead pipe for new plumbing in 1986, but that ban only stopped new installations. Homes connected to water systems before that year may still have the original lead service line in the ground, running from the municipal water main under the street to the point where it enters the foundation.

Pennsylvania is one of the states with among the highest concentrations of aging lead service lines, particularly in older communities in Chester, Lancaster, Berks, and Delaware Counties where housing stock from the early to mid-1900s is common. Many homeowners in these areas have never been told their service line material, because water utilities are only now completing the inventories required by the updated federal rule.

The health stakes are real. Lead exposure from drinking water is associated with neurological damage in children, cardiovascular effects in adults, and developmental harm in infants receiving formula mixed with tap water. There is no safe level of lead exposure according to the CDC. Knowing whether your service line is lead is the first step toward protecting your household.

Where to Find Your Water Service Line

Before you can run the test, you need to find the right pipe. The water service line is the pipe that carries water from the street into your home. It enters the building through the foundation wall or floor, typically in the basement or utility room, and connects to your water meter and main shutoff valve.

Here’s where to look:

•        Go to your basement or crawlspace. The service line usually enters through the wall or floor closest to the street side of the house.

•        Follow the pipe from the point it enters the building to where it connects to the water meter. The section between the foundation entry point and the meter is your test area.

•        If the pipe is wrapped in insulation, tape, or paint, you’ll need to expose a small section of bare metal to test. Peel back or cut away a small area of covering material to access the pipe itself.

Important: test the pipe between where it enters the building and the meter. Internal plumbing pipes inside the home may be a different material from the service line, so testing a pipe further inside the house won’t tell you what you need to know about the incoming line.

The Two-Step DIY Test: Magnet and Scratch

You need two items: a refrigerator magnet (or any reasonably strong magnet) and a coin or house key. That’s it.

Step 1: The Magnet Test

1. Hold the magnet against the surface of the pipe in your test area.

2. If the magnet sticks firmly, the pipe is galvanized steel, not lead. Galvanized steel is magnetic; lead is not.

3. If the magnet does not stick, the pipe is lead, copper, or plastic. Move on to Step 2 to distinguish between them.

Step 2: The Scratch Test

4. Use the edge of a coin, a key, or a flathead screwdriver to scratch gently through any surface corrosion or oxidation on the pipe. You don’t need to scratch deep, just enough to expose the underlying metal.

5. If the freshly scratched area is shiny silver and the metal feels soft and easy to scratch, the pipe is lead.

6. If the scratched area shows a copper or golden color, like a new penny, the pipe is copper. Copper pipes also won’t attract the magnet.

7. If the pipe is white, gray, or black and rigid or flexible plastic-feeling material, it’s a plastic pipe such as PVC or polyethylene.

One additional visual clue for lead: look for a swollen joint that looks like a bulge or blob where two pipe sections meet. That’s called a wiped joint, a hand-formed lead joint characteristic of older installations. If you see one, you almost certainly have a lead service line even before running the scratch test.

What Each Result Means at a Glance

•        Magnet sticks, scratch stays dull gray: galvanized steel. Not lead, but may still carry trace lead if downstream of a lead section. Note the finding.

•        Magnet does not stick, scratch is shiny silver, metal feels soft: lead. Schedule a professional assessment and contact your water utility.

•        Magnet does not stick, scratch reveals copper or gold color: copper. No immediate lead concern from this pipe.

•        No metal exposed, pipe is plastic or rubber: plastic. Generally safe from lead, though check fittings and connectors.

If the result is unclear because the pipe is painted, deeply corroded, or fully wrapped, contact your water utility or a licensed plumber. Pennsylvania utilities are now required to maintain service line inventories and in many cases can tell you the known material type for your address without a site visit.

What to Do If the Test Comes Back Positive for Lead

Finding lead in your service line doesn’t require panic, but it does require action. Here’s what to do in order.

Run your water before using it. Until the line is replaced, flushing cold water from the tap for 30 to 60 seconds before drinking, cooking, or preparing infant formula reduces lead exposure from water sitting in the line. Use a filter certified for lead removal, such as one carrying NSF/ANSI Standard 53 certification, as an interim measure.

Contact your water utility. Under Pennsylvania DEP requirements, utilities are now notifying customers served by known or suspected lead service lines. Contact your utility and ask for your address’s service line inventory status. Some utilities in PA have programs that fund full lead service line replacement including the portion under the homeowner’s property, particularly for income-qualifying households.

Schedule a professional inspection and get the replacement process started. Lead service line replacement involves removing the existing lead pipe from the curb connection to the meter and installing a new copper or approved alternative line. A licensed plumber can assess the full length of the line, confirm whether the utility-side portion is also lead, and coordinate the replacement so both sides are done at the same time. Replacing only the homeowner-side portion while leaving a lead utility-side pipe in place can temporarily increase lead levels in water due to disturbance of the remaining pipe.

Don’t delay because the water ‘tastes fine.’ Lead has no taste, odor, or color in water. You cannot detect it without testing. The EPA estimates that up to 9 million homes nationwide are still connected through lead service lines, with Pennsylvania among the states with higher concentrations.

The Pennsylvania and Federal Replacement Timeline You Should Know

The EPA finalized its Lead and Copper Rule Improvements in October 2024, with an effective date of December 2024. The rule requires water utilities to replace all lead service lines within 10 years, by the end of 2034. Pennsylvania utilities are already required to have submitted full service line inventories to the DEP by October 2024 and to be notifying affected customers.

Pennsylvania’s Act 120 of 2018 allows utilities to replace the customer-owned portion of a lead service line and recover costs through rates, which means some PA utilities are replacing both the utility side and property side of lead service lines at once, reducing or eliminating out-of-pocket costs for homeowners. The specifics vary by utility. Ask your water provider directly what their replacement program covers for your address.

Tri-County Water Services handles lead water line replacement across Lancaster, Chester, Berks, and Delaware Counties. If your DIY test indicates a lead service line, or if you’d like a professional to confirm the pipe material before you proceed, call us at 610-857-1740 or visit us.

Five Minutes Now, Years of Protection After

The scratch and magnet test takes less time than reading this post. If you’ve never checked the service line in your home and your house predates 1986, doing it today costs nothing and could directly affect your family’s health. If the result is lead, the path forward is clear: filter your water in the interim, contact your utility, and get the replacement scheduled. Tri-County Water Services can assess the full line, coordinate with your utility on the utility-side portion, and handle the installation.

Frequently Asked Questions

Q: How accurate is the scratch and magnet test for identifying a lead service line?

The scratch and magnet test is the same method recommended by the EPA and used by water utilities for residential service line identification. It’s highly reliable when performed on an exposed section of bare pipe between the foundation entry point and the water meter. The main limitation is that painted, wrapped, or fully concealed pipes can’t be tested without first exposing the metal, and some older homes have joints or connectors that are a different material than the main pipe run.

Q: My home was built after 1986. Do I still need to check?

If your home was built after 1986 with a new water connection installed at the same time, you almost certainly don’t have a lead service line. However, if the home is newer but sits on property that previously had a different structure connected to a pre-1986 service line, or if the service line was installed before the 1986 ban and reused during construction, a check is still worthwhile. When in doubt, run the test.

Q: What is a lead service line replacement and how disruptive is it?

Lead service line replacement involves excavating and removing the pipe that runs from the water main at the street to your home’s meter, then installing a new copper or approved alternative pipe in its place. The work typically takes one to two days. There will be a water shutoff for the duration of the work and some excavation in the yard along the pipe path. The disruption is temporary and manageable compared to years of lead exposure from an unreplaced line.

Q: Is lead water line replacement covered by my water utility in Pennsylvania?

It depends on your utility. Pennsylvania’s Act 120 of 2018 allows utilities to fund and replace the customer-owned portion of a lead service line and recover costs through rates rather than billing the homeowner directly. Some PA utilities have programs that cover both the utility-side and property-side replacement at no direct cost to the homeowner, particularly for income-qualifying residents. Contact your water utility and ask specifically what their lead service line replacement program covers for your address.

Q: Can I use a water filter instead of replacing the lead service line?

A filter certified to NSF/ANSI Standard 53 for lead removal is an effective interim measure that significantly reduces lead exposure from drinking water. It is not a permanent solution. The filter only treats water at the point it’s used and doesn’t address exposure from other sources, and filters require regular maintenance and cartridge replacement to remain effective. Lead service line replacement eliminates the source of contamination rather than managing it.

Q: What if only part of my service line is lead?

Partial lead service line replacement, replacing only the homeowner-side portion while leaving a lead utility-side pipe in place, is not recommended and in many cases increases short-term lead levels in water due to pipe disturbance. EPA guidance and current best practices call for full replacement of the entire service line from the main to the meter in a single operation. If your utility is replacing their side, coordinate to have both done at the same time.

Q: How long does lead service line replacement take in Pennsylvania?

Most residential lead service line replacements are completed in one to two days. The timeline depends on pipe length, depth, and soil conditions. Some installations require permits from your municipality or coordination with the water utility for the curb-side connection. A licensed plumber familiar with local requirements can give you a realistic timeline and handle the permit and utility coordination on your behalf.