Lead service line inventory: LCRI requirements & deadlines.
A lead service line inventory is a record of every service line connecting the water main to a building, classified by material — lead, galvanized requiring replacement (GRR), non-lead, or unknown. Under the EPA's Lead and Copper Rule Improvements (LCRI), water systems must maintain this inventory and submit a baseline inventory and a replacement plan by November 1, 2027.
The four service line material classifications
Lead
The service line is confirmed lead. These must be replaced under the mandatory LCRI replacement program and trigger consumer notification.
Galvanized requiring replacement
A galvanized service line that is or ever was downstream of a lead service line, is currently downstream of a lead-status-unknown line, or that the system cannot demonstrate was never downstream of a lead line — it can accumulate and release lead, so the LCRI treats it like a lead line for replacement.
Non-lead
Verified to be a non-lead material (copper, plastic, etc.). Once verified with acceptable evidence, it does not require replacement.
Lead status unknown
Material not yet identified. Unknowns must be investigated and reclassified — until then they are treated as lead for notification purposes.
Key LCRI deadlines
Oct 16, 2024 — initial inventory
The first service line inventory was due to the state under the LCRR. Most systems have submitted an initial inventory with unknowns still to resolve.
Nov 1, 2027 — LCRI compliance date
The baseline inventory, the lead service line replacement plan, a list of schools and child cares, and an updated sampling plan are all due.
Annually (since November 2024)
Systems must send annual notification to customers served by lead, GRR, or unknown service lines, using the required health-effects language, until each line is verified non-lead or replaced.
By 2037 — full replacement
Water systems (community and non-transient non-community) must replace all lead and galvanized-requiring-replacement (GRR) service lines — generally within ten years of the November 1, 2027 compliance date. EPA sets the replacement rate, not a specific calendar day.
The inventory is a spreadsheet problem — until it isn’t.
Getting to a clean baseline means validating thousands of rows against the EPA template, resolving unknowns, generating a replacement schedule, and producing the annual notifications — every year through 2037.
1water is building an LCRI toolkit — inventory validation, a replacement-plan generator, and notification drafting — so small systems can meet the November 2027 deadline without an enterprise contract. Tell us your state →
Lead service line inventory — common questions
- U.S. EPA — Lead and Copper Rule Improvements (LCRI), final rule (October 2024).
- U.S. EPA — Final LCRI Fact Sheet: Service Line Inventory.
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