Lead Service Lines, Utility by Utility

Your water utility holds an inventory: its record of what it believes each service line in its territory is made of. That record is the answer for your address, and nationally its largest single category is "unknown", 22,390,206 lines against 2,188,033 recorded as lead. Enter your ZIP in the tool on this page to get the water systems serving your county and what each one reported to EPA, then go to that system's own inventory for your address. If it comes back unknown, that is a real answer about the state of the record, and the utility owes you a plan to resolve it. Only a laboratory test of your tap measures your water.

EPA set them in the Lead and Copper Rule Revisions: "All systems must develop an initial lead service line (LSL) inventory by October 16, 2024, that includes all service lines, regardless of ownership, categorized as lead, non-lead, galvanized requiring replacement (GRR), and unknown." Lead means the utility records the line as lead. Galvanized requiring replacement means galvanized pipe downstream of lead, which the rule treats like lead because it holds lead picked up from it. Non lead means something else, usually copper or plastic. Lead status unknown means nobody has established it. Those are the only four, and every count on this site uses them exactly as EPA defines them.

Across 48,630 community water systems in the April to June 2026 federal extract: 2,188,033 lead service lines, 996,883 galvanized requiring replacement, 22,390,206 of unknown material and 76,488,156 non lead. 44,232 systems reported all the categories they owed, 908 reported some, and 3,490 reported none at all. The headline is not the 2,188,033: it is that the unknown column is roughly ten times the lead column, so most of the country's answer is still outstanding.

Yes: "All systems must develop an initial lead service line (LSL) inventory by October 16, 2024, that includes all service lines, regardless of ownership, categorized as lead, non-lead, galvanized requiring replacement (GRR), and unknown." EPA's compliance file records who did not. 4,902 community water systems carry a listed LSL Inventory violation, and 8,079 carry some service line specific violation, of which 3,197 are still listed as unaddressed or being resolved. Read those as paperwork rather than pipe: a system with no violation filed something, which says nothing at all about what the something said.

Two more dates. On the inventory: "Develop an updated initial service line inventory, called the LCRI baseline inventory, that includes updated service line information and connectors. The baseline inventory is due by November 1, 2027." On the pipe: "EPA is requiring water systems to conduct full replacement of all lead and galvanized requiring replacement (GRR) service lines that are under the control of the water system in 10 years or less, with limited exceptions, regardless of the water system’s 90th percentile lead level." Utilities must also tell people who may be affected in the meantime: "Notify customers and persons served by a service line that is known to or may potentially contain lead (lead, GRR, or lead status unknown service lines)." That last one is why some households have received a letter saying their line is unknown; the letter is the rule working, not a finding about the house.

They are different measurements of different things. The inventory is a record of PIPE MATERIAL, compiled from utility records and field checks. The 90th percentile lead level in a water quality report is a compliance STATISTIC from tap samples drawn at a targeted pool of higher risk homes, expressed in parts per billion. A system can have a low 90th percentile and thousands of lead lines, and EPA's replacement requirement applies "regardless of the water system's 90th percentile lead level". Nationally 415 systems with a recent, plausible result sit at or above the 15 parts per billion action level.

No. EPA: "Among homes without lead service lines, the most common problem is with brass or chrome-plated brass faucets and plumbing with lead solder." The service line stops at the building. Lead solder was legal in household plumbing until 1986 and brass fixtures could legally contain lead well after that, so the inside of a house can add lead to water that arrived through a copper or plastic service line. That is also why running the tap before drinking, and testing, are about the whole path rather than the buried part of it.

Usually one of two reasons, and they look identical in a table. Some states genuinely built most of their distribution after lead pipe went out of use, and finished counting: Oregon reported no lead and no galvanized requiring replacement with only 2.2 percent of lines unknown. Others simply have not looked yet: 16 states land on this site's unknown shape because a large part of what they reported has no established material or a large share of their systems reported nothing. A small number with a large unknown column beside it is not a finding.

EPA's 7th Drinking Water Infrastructure Needs Survey and Assessment projects 2,659,983 lead service lines and 1,296,400 galvanized requiring replacement, about 3,956,383 together, which is larger than the 3,184,916 reported here. The difference is the unknowns. EPA's own description of the method: "Consistent with the approach used previously for the 7th DWINSA, EPA predicted how many of the unknown material service lines were likely to be lead service lines." It does that with a state specific ratio of lead to identified pipe. Those projections allocate federal money, and they are labelled projections wherever they appear here, separate from the reported counts.

EPA's SDWIS service line inventory report and EPA's quarterly Safe Drinking Water Act download, both April to June 2026, both US Government works in the public domain. Two things it misses by construction. Private wells: no lead rule covers them, so a household on its own well has no inventory and no utility. And 748 tribal water systems that the federal file records with no usable county, which means the ZIP tool may not list a tribal system that serves you. Non transient non community systems such as schools and workplaces owe inventories too; these pages cover community water systems.