Michigan still has 315,372 water service lines of unknown material

Michigan water systems reported 315,372 service lines of unknown material in 2024, even as replacement work has accelerated statewide. A Shelby Township plumber says homeowners can check their own line in minutes and should know who pays if the pipe turns out to be lead.

Why it matters: - Michigan still has a large blind spot in its drinking water infrastructure, with 315,372 service lines listed as unknown material in the state’s October 2024 inventory. - Lead service lines can pose a health risk, and line replacement affects who pays, how fast work happens and whether homeowners need to take action. - Statewide replacement is advancing, but the scale of the unknown inventory shows many homes still need confirmation.

What happened: - Michigan water systems filed service line inventories in October 2024. - The inventories listed 315,372 lines as unknown material, 203,050 as lead and 61,608 as galvanized steel lines that are or were connected to lead. - EGLE describes the inventory as “a snapshot in time,” and systems have kept updating it. - State progress data shows 98,253 lead and galvanized service lines were replaced in Michigan from 2021 through 2025. - Annual replacements increased from 10,316 in 2021 to 28,332 in 2025. - In Detroit, the Detroit Water and Sewerage Department listed more than 80,000 lead service lines and 15,855 replacements since 2018 as of March 2026. - Imad “Matt” Mansour, owner of Mansour’s Innovations in Shelby Township, said homeowners should first find out what kind of pipe they have before worrying about the bill.

The details: - Michigan’s Lead and Copper Rule requires water systems to replace every lead service line at an average rate of 5% a year over no more than 20 years, starting in 2021. - EGLE says the full lead service line must be replaced at water supply expense, regardless of ownership. - Galvanized lines that are or ever were connected to lead must also be replaced. - Partial replacement of a lead line is no longer allowed except in an emergency repair. - A federal rule adopted in 2024, the Lead and Copper Rule Improvements, sets a national deadline of December 31, 2037. - The federal rule is in effect but is being challenged in federal court by water utility groups. - Homeowners can check a line in two minutes by finding where the water line enters the basement wall or floor, usually near the water meter. - The check calls for scraping a small spot on the pipe before the meter with a coin or key and holding a magnet to it. - Copper scratches to a shiny penny color and does not attract a magnet. - Lead looks dull gray, is soft, scratches to a bright silver color and does not attract a magnet. - Galvanized steel is gray, hard to scratch and attracts a magnet. - Plastic service lines are usually white, blue or black. - Homeowners can take a photo and send it to their water department. - Every community water system in Michigan must keep an inventory of service lines, and a homeowner photo can help resolve an unknown listing. - Mansour said galvanized pipe is often missed because it looks like ordinary gray pipe, rusts from the inside and can reduce water pressure over time. - Mansour also said the state counts galvanized line as lead-related if it was ever connected to lead.

Between the lines: - The unknown category suggests many systems still lack enough field verification to identify every pipe material. - The replacement figures show that the state’s lead-line work is underway, but not finished, and Detroit alone remains a major part of the problem. - The rules shift financial responsibility away from many homeowners when lead is involved, which changes the urgency of checking a line before hiring a contractor. - Mansour’s advice reflects a practical point: a homeowner who pays for the wrong repair may spend money on work the water system must cover.

What’s next: - Michigan water systems will keep updating inventories as more service lines are identified. - Homeowners who find lead should contact their water department before hiring a contractor and ask where they are on the replacement list. - Homeowners with non-lead lines that are failing may still need to arrange and pay for repairs, depending on local rules. - Mansour’s Innovations continues replacing water service lines across Macomb, Oakland and Wayne counties with copper or PEX and coordinates permitting, utility marking and meter work.

The bottom line: - A quick visual check can tell Michigan homeowners a lot about their water line, and in many cases it can determine whether the bill belongs to them or the water system.