Idaho Tap Water Quality Report

The tap water quality in Idaho currently sits near the national average, registering a composite safety score of 65.7/100 across 324 monitored ZIP codes. While a significant portion of the state maintains adequate water quality and full compliance with federal standards, 1% of ZIP codes in Idaho have received a failing grade due to recent compliance issues. Monitoring data from the EPA indicates that while the majority of residents receive safe tap water, localized issues remain a challenge for several municipal systems.

Over the past 5 years, water utilities in Idaho have recorded a total of 1,665 violations, of which 278 were strictly health-based. While administrative and reporting violations are common nationwide, health-based violations mean that certain contaminants exceeded the EPA's Maximum Contaminant Levels (MCLs) at some point. Idaho Department of Environmental Quality, which acts as the primary regulatory authority in the state, typically works closely with these utilities to issue boil water advisories or mandate infrastructure upgrades when these limits are breached.

One of the most pressing concerns for Idaho residents is the elevated risk of lead exposure. EPA models and historical monitoring indicate that 48.1% of ZIP codes in Idaho are classified as High or Very High risk for lead. This is frequently associated with older housing stock built before the 1986 federal ban on lead pipes and solder. Residents living in older homes should strongly consider having their tap water independently tested and utilizing a certified NSF/ANSI 53 water filter for drinking and cooking.