Lead Pipe Inventory: Quarterly Movement

Data current as of June 2026. Recomputed by ZipCheckup from federal data each build.

Between 2026Q1 and 2026Q2, EPA SDWIS records show a net change of +194,299 lead lines and -623,674 unknown-material lines, with 1,526 systems completing their inventory.

By state

We report two independent facts side by side and do not rank states. A larger count reflects the size of a state's inventory and its reporting activity, not a judgment about water safety.

How we compute this

We diff two consecutive federal SDWIS snapshots and sum the signed change per category across every reporting system. A negative net-unknown means utilities reclassified previously-unknown lines after physically verifying them.

Direction is reported, not judged. A change in lead-classified lines reflects reclassification and replacement together; we do not attribute causation between the two.

Systems that started or stopped reporting between snapshots are counted as reporting transitions, not as numeric changes from zero, so a new reporter never inflates the movement totals.

Frequently asked questions

@misc{zipcheckup-findings-lead-pipe-inventory-quarterly-movement,
  author = {{ZipCheckup}},
  title  = {{Lead Pipe Inventory: Quarterly Movement}},
  year   = {2026},
  url    = {https://zipcheckup.com/findings/lead-pipe-inventory-quarterly-movement/}
}