Maybe the City’s service line inventory just told you “suspected lead,” or you closed on a 1920s bungalow and want to know what’s coming through the basement wall. Chicago Plumbworks sets up lead water line checks and replacements across Chicago, done by a licensed plumber. The Department of Water Management counts about 400,000 lead service lines in the city, most of them feeding houses and two-flats built before 1986.
Chicago lead service line replacement runs from the water main in the street to the first shutoff valve inside your house. A licensed plumber can check the pipe at your meter and then do the replacement, with the City making the final connection at the main. Water already seeping where the line comes through the foundation is a leak that can’t wait, so call about that first.
How to check if your line is lead
Short answer
Find the pipe that comes through your basement wall and into the water meter. Scratch it gently with a coin or key, then hold a strong magnet to it. A soft, shiny silver scratch that the magnet won’t grab points to lead. Copper scratches to a penny color, and galvanized steel holds the magnet.
This is how to check for a lead pipe using the method the Department of Water Management gives Chicago owners. You need a coin or a house key, a strong refrigerator magnet and your phone for a photo.
Find where the water line comes in
In the basement, find the pipe that comes through the wall from the street side and runs into the water meter. If the meter is outside in a vault, use the pipe where it enters the house. No meter? Start at the main shutoff valve.
Get to bare metal
Pick a spot on that pipe between the wall and the meter. If it's painted, sand a small patch first. Skip knives and sharp tools, and don't dig into the pipe.
Scratch it with a coin or key
Scratch gently with the flat edge, the way you'd scratch a lottery ticket, and look at the color that shows.
Hold a strong magnet to it
Set a strong refrigerator magnet on the scratched spot and see whether it grabs the pipe or slides off.
Match what you see
Shiny silver and the magnet won't stick: likely lead. Penny-colored and no stick: copper. Silver-gray, hard to scratch and the magnet sticks: galvanized steel. Wash your hands, then photograph the scratch and the meter.
Use the tap test only to back up the scratch and the magnet, since a dull sound is easy to second-guess.
| What you check | Lead | Copper | Galvanized steel |
|---|---|---|---|
| Coin or key scratch | Scratches easily to shiny silver | Bright orange, like a new penny | Hard to scratch, stays silver-gray |
| Strong magnet | Won’t stick | Won’t stick | Sticks |
| Tap with a coin | Dull thud | Clear metallic sound | Clear metallic sound |
| What it means here | The line to replace | What new service lines are made of | Can still need replacing if it sat downstream of lead |
Plastic service lines, usually white, are uncommon in Chicago.
Go easy on the scratch. Lead is very soft, and the City’s instructions rule out knives and sharp tools so nobody puts a hole in the pipe. If you can’t find the meter, or you’d like to know where the main valve is before you touch anything, finding the main shutoff in your building goes through it by house type.
Your address in the City’s inventory
The City’s service line lookup searches by building address or water account number. Type the address with the direction letter and St or Ave, no punctuation, and leave off any unit number. The record covers the whole building, so a two-flat or three-flat owner checks it once.
Your result splits the line at the b-box, the shutoff valve between the street and your house. The public side runs from the water main to the b-box. The private side runs from the b-box into the building. Each side gets one of four labels: not lead, lead, galvanized requiring replacement, or suspected lead.
Look at what the label is based on, too. Field verification means someone working with the department has seen the pipe. Building age means the label is an assumption from the year the house went up, and a scratch test at your meter is how you turn that into a fact. The map pin is only approximate, and if your address doesn’t come up, the lookup page has a contact form.
Bungalows, two-flats and pre-1986 homes
City code required lead water lines until 1986, the year a federal ban ended new lead pipe. So lead pipes in Chicago turn up across most of the older housing: worker cottages, greystones, two-flats, the brick bungalows that went up from about 1910 to 1940, and the postwar houses that came after them. The City’s rule of thumb is that a house, two-flat or small building from before 1986 is likely to have a lead line. Larger buildings usually don’t.
The exception is a line that was replaced during a renovation or an addition. Ask about it on any rehab you buy. New copper in the kitchen and baths tells you nothing about the pipe coming through the front wall, which stays where it is unless someone replaced it from the house out to the main.
Some older lines are galvanized steel instead of lead. The inventory’s “galvanized requiring replacement” label covers galvanized pipe that is, or ever was, downstream of a lead line. Lead can cling to the inside of galvanized pipe and come loose into the water over time.
The service line also isn’t the only place lead turns up. The City notes that pre-1986 houses and two-flats can have lead in the pipes inside the house and in faucets and fixtures, so the plumber’s look shouldn’t stop at the meter.
What replacement involves
Replacing a lead water line means a new copper line from the water main in the street all the way into the house. In Chicago, state law has required the whole lead line to come out since January 2023, public side and private side. A short run of copper spliced onto old lead is no longer allowed.
The new line goes in one of two ways. An open trench runs from the house through the parkway to the main. Trenchless work runs the new line underground with far less digging. The right method depends on details of your address, so ask at the walk-through which one fits and why.
Inside, the new copper comes through the foundation to the meter and the first shutoff valve. If the house has no meter, one goes in. The plumber handles the permits, starting with the Department of Buildings and a Chicago Department of Transportation permit for work in the public way. Some addresses need an IDOT permit too.
If the water heater is leaking or close to the end of its life, ask about replacing the tank during the same shutdown, since the water is already off for the service line.
The day the line gets replaced
On a typical replacement, plan on:
- A walk-through before any digging, where you agree on how the work gets done and how much of the yard and parkway gets put back.
- Clear room at the basement wall where the line comes in, and at the meter.
- No water while the old line comes out and the new one is tied in.
- Possibly two visits, since the public side and the private side can be done on different days.
- A City inspector checking the installation before Water Management makes the connection at the main.
Flushing after the work
Digging and pipe work can knock small particles loose, lead among them. The City’s instructions call for intensive flushing every two weeks for three months after any work on your water system. Take the aerators off every faucet, open the cold taps all the way starting in the basement and working up, and run them for 30 minutes.
The City’s replacement programs, by name
The City’s lead service line replacement program runs through Lead-Safe Chicago, a City of Chicago project that lists five ways a lead line gets replaced. Some you apply for, and some start with a break or with City work on your block.
- Equity Lead Service Line Replacement Program. For owners who live in the home and have a household income below 80% of the area median. Homes with children 18 and under, or with high lead results from City testing, get priority. You apply with proof of income and ownership, and a City-provided contractor does the replacement.
- Homeowner-Initiated Program. For owners who hire their own licensed plumber to replace the full line. It has to be a standalone job, not part of a renovation or an addition. Commercial and mixed-use buildings aren’t eligible right now, so a storefront with flats above doesn’t qualify. The plumber files the job with the Department of Buildings as a lead line replacement, and the City makes the connection at the main and supplies a meter if there isn’t one. Call us for this one, and a licensed plumber can check the line and plan the replacement around your schedule.
- Daycare Lead Service Line Replacement. For licensed daycares in neighborhoods the City has prioritized. The Department of Water Management contacts the daycares that qualify.
- Breaks and Leaks Replacement Program. When a lead line breaks or leaks and needs repair, the break has to be reported to the City, and Water Management schedules replacement of both sides. Leaks in the pipes inside the house aren’t part of it.
- Block-long Replacement Program. When Water Management replaces the water or sewer main on your block, the lead lines that work touches get replaced too.
The applications and the current eligibility rules are on the City’s lead line program page.
Illinois’ Lead Service Line Replacement and Notification Act and the federal Lead and Copper Rule Improvements require the City to replace every lead line it has. The City’s 2025 plan targets about 8,300 replacements a year starting in 2027, so with roughly 400,000 lines in the ground, a block’s turn can be years away.
Filters while you wait
A lead line doesn’t automatically mean lead in your glass. The City adds a corrosion-control treatment that coats the inside of the pipes, and results vary from house to house with how much water gets used and how long it sits. Until the line is out, a filter on the water you drink and cook with lowers the risk.
Pick a filter certified to NSF/ANSI Standard 53 for lead reduction. That’s the certification the CDC and the City point to, so look for it on the package rather than going by the brand. The CDC adds NSF/ANSI 42 for particles. Keep using the filter for at least three months after the new line goes in, the window the City recommends after any construction. Change cartridges on the maker’s schedule.
A few habits help in the meantime:
- Run the cold tap for at least five minutes when the water has sat for six hours or more, like first thing in the morning. A shower or a load of laundry counts toward it.
- Use only cold water for drinking, cooking and baby formula. Hot water picks up more lead, and boiling won’t take it out.
- Clean the aerator screens on your faucets now and then.
Older Chicago house, other plumbing trouble?
- Water coming up the floor drain in a storm is a sewer-side problem with its own fixes.
- Roots growing into the old clay sewer show up as slow drains and backups all through the house.
- A beeping alarm on the ejector pit in a garden unit means the pump is losing to the water.