6,719 U.S. Schools Are Their Own Water Utility. 301 Still Haven't Inventoried Their Lead Pipes.

Most American schools drink city water. Some are the city.

6,719 active public water systems in the United States are flagged in the EPA's own inventory as a school or daycare. Not "a school served by a utility" — the school is the utility. It runs the well, does the treatment, files the reports, and answers for the water coming out of the fountain. Together they serve about 3.3 million people, and the median one serves 200.

We pulled the EPA's violation records for all 6,719. 381 are under at least one open health-based violation — roughly 1 in 18.

Here's the part that matters. Not one of those 381 is a contaminant measured over a federal limit. Every single one is a treatment-technique violation: a required step that didn't happen. And 301 of them — four out of every five cited schools — are the same missing step.

Nobody has said what the pipes are made of.

The violation, and what it actually is

Why the school system is cited	Systems
Lead service line inventory not produced	301
Failure to address a groundwater-rule deficiency	26
Corrosion control study/recommendation not submitted	24
Corrosion control treatment not installed or demonstrated	14
Coliform Level 1 assessment not completed	11
Lead public education not delivered	7
No certified operator	2
Failure to filter surface water	1
Lead service line replacement behind schedule	1

The top line is the Lead and Copper Rule Revisions inventory. Every community and non-transient water system in the country — every one of these schools included — had to catalog each service line and classify it as lead, galvanized, non-lead, or unknown, and submit it by October 16, 2024. It is the foundation the whole federal lead program now rests on: the replacement deadlines, the notification rules, the funding formulas all key off it.

301 schools and daycares, serving 127,153 people, have not satisfied it and the violation is still recorded as open.

That is not the same as finding lead. It's the more uncomfortable thing: for those buildings, the question of whether children are drinking through lead pipes has no answer on file.

Nationally, 2,968 water systems of all kinds carry the same open inventory violation — it's the single most common health-based violation in the country, of any type. Schools are 301 of them.

Where the cited schools are

State	School water systems	Under an open health-based violation	Share
California	412	97	24%
Connecticut	210	89	42%
Texas	161	27	17%
Florida	195	23	12%
New Mexico	62	15	24%
New Jersey	261	13	5%
Maryland	283	13	5%
Arizona	107	12	11%
North Carolina	175	9	5%
Oregon	164	9	5%
Pennsylvania	500	9	2%
Oklahoma	37	8	22%

Connecticut is the number. 42% of Connecticut's school water systems — 89 of 210 — are under an open health-based violation, the highest rate in the country by a wide margin. Connecticut also ranked third nationally for health-based water violations by state, ahead of states many times its size, so this is consistent with how that state's records look overall.

Now read the table the other way. Pennsylvania has 500 school water systems and 9 citations. Michigan has 632 and one. Ohio has 198 and none. Minnesota has 134 and none. Twenty-two states and territories have not cited a single school system.

Both readings can't be about water. The states with the most cited schools — California, Texas, Connecticut, Florida — are the same states leading the LSL inventory violation across all system types. What this table is measuring, at least in part, is which state agencies have enforced the new inventory rule and recorded the failures. A zero in this table is not proof that a state's school pipes are known and safe. It may mean nobody has been asked.

That cuts against the instinct to read the ranking as a scoreboard. The honest version: 301 confirmed schools where the pipes are undocumented, and an unknown number of others in states that haven't checked.

The biggest ones

Every system below is on the map, with its full contaminant record:

• Cal Poly Pomona — 29,854 served, the largest school system on the list by a factor of ten
• Rio Mesa High School, Oxnard, CA — 2,600
• Ridgefield High and Middle School, CT — 2,575
• Tomball ISD Rosehill Elementary, TX — 2,519
• Medina Valley High School, Castroville, TX — 2,501
• Selma High School, CA — 2,225
• New Fairfield Elementary School, CT — 1,425

Below those, the list flattens fast into systems serving 200 people — one rural elementary school on one well. Which is the structural problem underneath all of this. A city utility has a compliance department. A K-8 school with 200 students has a facilities director who also handles the boiler, and a federal inventory requirement landed on the same desk.

What this doesn't tell you

A missing inventory is not a lead reading. None of these 301 schools has a lead measurement over the federal action level in this data. The violation is that the material of the lines was never established. The risk is unquantified, not confirmed.

A lead service line is not automatically lead in the water. Corrosion control chemistry can keep lead bound in the pipe wall for decades. The line's existence is a hazard to manage, and managing it starts with knowing where it is — which is the entire point of the inventory.

This only covers schools that run their own water system. If your child's school is on city water, it isn't in this dataset, and its own building plumbing — the fixtures, the solder, the internal lines — isn't covered by the school's water bill either. Federal lead sampling happens at the utility's worst-case residential taps, not at the school's fountains. Look up the system that serves the school's address instead.

Nothing here covers microplastics. The EPA does not regulate them in drinking water, so no school, and no utility, is required to test for or report them, and none of these compliance records would show them. That's a gap in what's measured, not a clean bill. If you want to know whether particles are coming through a specific tap, it has to be tested directly — you can run a microplastics test kit on the water yourself and count what's in it.

Look up any school

Every one of the 6,719 school and daycare water systems has a page on this site, with each contaminant it reported and how those numbers compare to the federal limits. Search a town on the map and the school systems appear alongside the municipal utility — they're often the only other pin for miles.

Counts are from the EPA's Safe Drinking Water Information System: active public water systems flagged as a school or daycare, cross-referenced against federal violation records. "Open" means a violation recorded as Unaddressed or Addressed — not resolved. "Health-based" is the EPA's own classification for violations tied to a health standard rather than a paperwork rule. For the wider picture, see drinking water violations by state and lead in the 25 biggest cities.