OWASSO: EPA violation history, explained
OWASSO had a health-based violation within the last five years. The required corrective action was reported, but it happened recently enough to matter. It serves 23,000 people through 10,468 service connections.
Ranked against every other system in this dataset
30 total violations and 8 health-based ones put OWASSO at the 82th percentile nationally for violation burden, rank 2,382 of 12,903.
How OWASSO compares within OK
OK's 240 covered systems average 39.5 health-based violations each; OWASSO carries 8, not more than typical for the state. See the lead and copper guide for why lead counts differently.
Most recent violation on record
The last violation EPA has on record for OWASSO is from 2025-05-10 (health-based: 2025-05-10). Last reported to EPA: 05/13/2026.
What kind of problem, specifically
OWASSO's flagged contaminants and rule violations, grouped by what they actually mean for a filter choice rather than left as EPA's raw code list:
- Lead & copper - flagged from: LEAD AND COPPER RULE REVISIONS
- Microbial contamination / treatment technique - flagged from: Coliform (TCR)
The most severe category on record is lead & copper, which points toward a lead-class filter if you want to address it directly.
What this data is and is not
OWASSO's numbers here come from its own required reporting to EPA under the Safe Drinking Water Act, not from an independent test of your glass of water. This record - 8 health-based violations on file for OWASSO - stops at the meter and cannot see household plumbing on the other side of it. The guide to what this data misses covers that gap.