Is HILO's water safe to drink?
HILO has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. Population served: 39,477, over 14,621 connections.
Ranked against every other system in this dataset
Out of 12,903 systems in this dataset, HILO ranks 298th by violation burden (98th percentile) - 49 violations total, 48 health-baseds.
Against the HI average
HI's 47 covered systems average 8.4 health-based violations each; HILO carries 48, more than typical for the state. See the lead and copper guide for why lead counts differently.
Most recent violation on record
HILO's most recent violation on record is dated 2009-01-01, with the most recent health-based one dated 2009-01-01. Last reported to EPA: 06/03/2026.
The concern categories on record
HILO'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:
- Microbial contamination / treatment technique - flagged from: Surface Water Treatment Rule
The most severe category on record is microbial contamination / treatment technique, which points toward a microbial-class filter if you want to address it directly.
What HILO's record does not cover
Everything on this page is HILO's own reported record under the Safe Drinking Water Act - a regulatory filing, not a sample of your tap. Water quality can still change between the meter and the faucet - household plumbing sits outside what a record of 49 logged violations can see. The guide to what this data misses covers that gap.