Water quality for ZIP code 59623
ZIP 59623 covers Helena in Lewis and Clark County, Montana, one of 11 ZIP codes in the county. 164 active public water systems serve the county; 105 had an EPA violation in the past three years.
Most likely your provider
Other community water systems in Lewis and Clark County
55 systems, largest firstNon-community systems in Lewis and Clark County (108: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
About this data
Water systems are matched to Lewis and Clark County, the county this ZIP code lies in, largest first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility.
ZIP code areas and town boundaries come from the U.S. Census Bureau's 2020 ZCTA files.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Montana records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.