Indiana
Hamilton County drinking water quality
66 active public water systems serve 229,378 people in Hamilton County. 32 are compliant, 34 had at least one EPA violation in the past three years, 0 are designated serious violators, and 1 carries a health flag.
Needs attention
Community water systems
16 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Carmel Water Department Carmel |
99,927 | 1 | 0 | |
|
Citizens Water of Westfield, LLC Carmel |
61,493 | 0 | 0 | |
|
Indiana American Water Noblesville Noblesville |
45,575 | 0 | 0 | |
|
Cicero Water Department Cicero |
5,607 | 0 | 0 | |
|
Indiana American Water Sheridan Sheridan |
4,435 | 0 | 0 | |
|
Arcadia Water Department Arcadia |
1,515 | 0 | 0 | |
|
Atlanta Water Department Atlanta |
735 | 0 | 0 | |
|
Carmel Clay Water Carmel |
393 | 0 | 0 | |
|
Suburban Estates, LLC Noblesville |
350 | 0 | 0 | |
|
Hamilton County Regional Utility Cicero |
125 | 1 | 0 | |
|
Indiana Academy Cicero |
113 | 2 | 1 | |
|
Eagletown Estates Mobile Home Park Eagletown |
97 | 1 | 0 | |
|
Tall Timbers Mobile Home Park Noblesville |
90 | 2 | 0 | |
|
Maplewood Estates MHC LLC Noblesville |
37 | 2 | 0 | |
|
Little Eagle Creek Estates Westfield |
35 | 1 | 0 | |
|
Harris Hills Mobile Home Park Noblesville |
27 | 3 | 0 |
Non-community systems (50: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
Inactive systems (109, no longer operating or reporting)
Kept for the record and excluded from the county totals above. Browse inactive systems.
About this data
Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.
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 Indiana 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.