• For the second straight year, DWSD has mailed now-required annual notices informing residents and businesses that a portion or all of their water service line is made from either lead, galvanized or unknown may be lead pipe material

• With updated technology and data, 170,000 less addresses will receive a letter marked “unknown”

• Residents can access DWSD’s Water Service Line inventory utilizing a public map and verify their service line material at detroitmi.gov/DWSD

Last year, the Environmental Protection Agency (EPA) announced every city and township with lead and galvanized service lines are required to mail notification letters to every property with a verified or predicted lead service line, verified galvanized service line, or a service line of unknown material that may be lead. These notifications for Detroiters were mailed Tuesday, and other cities will send similar letters as well this year.

“The Detroit Water and Sewerage Department (DWSD) delivers clean, safe drinking water to our neighborhoods, and these notifications do not change this fact,” said DWSD Director Gary Brown. “The letters are a required annual communication to inform residents and businesses of the pipe material we have on record for their property and the necessary precautions. Because the letters are only necessary for properties with lead, galvanized or unknown material that may be lead, only 30% of Detroit addresses need to receive the notifications and that will continue to decrease as we improve not only our records but more importantly continue to replace lead service lines.”

The annual letters are required of all communities with municipal water service and lead service lines, mandated by the U.S Environmental Protection Agency (EPA) as part of the Lead & Copper Rule in the Safe Drinking Water Act. These notifications will continue until all the estimated 75,000 lead and galvanized service lines are replaced in Detroit.

More than 200,000 residents and businesses were sent notification letters last year using a federal template. With an accelerated rate of lead service line replacement, improved mapping technology thanks to a predictive model from Ann Arbor-based BlueConduit, and customer feedback, DWSD has mailed 123,387 letters. Residents and businesses that received a letter categorizing their service line as “unknown material” in November 2024 may not receive any notification this week or have changed from unknown to lead because of DWSD’s partnership with BlueConduit and its computer-based prediction technology.

Also, DWSD took public feedback from last year to make significant updates to the language in the letters beyond the required templates, including revising the explanations and adding new detailed images.

DWSD Deputy Director Sam Smalley, PE, said, “Our treated drinking water meets or exceeds Safe Drinking Water Act standards when it leaves the treatment plants, which contains no lead, and travels through the distribution system.”

Where can residents see the service line inventory?
DWSD launched its first lead service line replacement inventory map online for public access in October 2024. This interactive map, with real-time updates based on service line replacements, displays the verified or assumed status of residents’ pipe material. Residents can access the map by visiting detroitmi.gov/LSLR. Residents are encouraged to watch this video to learn how to navigate the map and determine if your water line material is assumed or verified.

How can residents verify service line material?
Residents can learn how to verify if they have a lead service line by using a magnet and a penny, visit this online tool. Once verified, take picture of their pipe and submit their results to DWSD using this online form. This self-verification is for the type of pipe material near the water meter inside your home or business. When DWSD crews are on your street replacing lead service lines in the coming years, we will verify the outside portion through exploratory hydro-excavation and if it is lead or galvanized, the service line will be replaced.

DWSD estimates there are 75,000 lead service lines in Detroit. Since 2018, DWSD has replaced nearly 15,000 lead service lines and has accelerated the pace of replacement since 2023. Utilizing a neighborhood-by-neighborhood approach, areas are being prioritized based on income, density of homes, and population consisting of seniors and children in the area. For a list of current and upcoming neighborhoods, visit detroitmi.gov/lslr.

Why do some residents and businesses receive a letter with “unknown service line that may be lead?”
DWSD engineers and other technical staff have dedicated the past six months to update the citywide service line inventory data based on pipe replacements, permit data, onsite verifications, and computer-based predictive modeling, according to Smalley. If all these steps did not yet indicate the pipe material for a specific address, it must be listed as “unknown” until DWSD receives additional data. The pipe material may or may not be lead, which is why there are precautionary tips in this notification.

When will homes and businesses stop receiving this annual notification?
Once the water service line is replaced with copper, it is no longer necessary to provide an address with existing lead or galvanized service lines with this annual notification. If unknown and may be lead pipe material notification is mailed to an address and DWSD later determines the property has an existing copper service line (or the lead line is replaced), then the notifications will end for the specific address.

Why do 70% of Detroit addresses not receive a letter?
If a resident or business does not receive a DWSD service line notification letter, the property has verified or predicted copper service line, cast iron, or other material and there is no need at this time to provide lead and drinking water safety instructions to this address. If a resident or business has information including photos that the water service line is made of lead, please use the submission form at detroitmi.gov/lslr.

What are the facts?
The drinking water leaving the four treatment plants serving Detroit, operated by the Great Lakes Water Authority (GLWA), does not contain lead, but lead can be released into drinking water from lead service lines and home plumbing as the water moves from the water mains to your tap. Beginning in 1945, Detroit stopped allowing the installation of lead piping for water service lines. Homes before 1945 are most likely to have a lead pipe that connects the home to the water main, known as a lead service line, unless it has been replaced. The lead in lead service lines, household plumbing and fixtures can dissolve or break off into water and end up in tap water. The water provided to DWSD customers contains a food additive corrosion inhibitor to reduce leaching from lead service lines and other lead components, but lead can still be present in water at the tap.

If you have a lead service line, use the steps below:

• Run your water to flush out your pipes. If water has gone unused in the home for six hours or more, run the water for 3-5 minutes to flush water from both the interior building plumbing and the lead service line. Lead levels are likely at their highest when water has been sitting in the pipe for several hours.
• Use only cold water for drinking and cooking; lead dissolves more easily into hot water.
• The most reliable method is to use a water filter certified to reduce lead in the water. If you have a lead service line or if there is a pregnant woman or children aged 6 and under in your home, use a filter that meets NSF standard 53 for lead removal for drinking and cooking. Always use a filter or bottled water If you are preparing formula for an infant. DWSD provides water filter pitchers when on the block replacing the water main and lead service lines.
• Clean your aerators monthly. Aerators are small attachments at the tips of faucets which regulate the flow of water. They can accumulate small particles of lead in their screens.