CITY REPORT
IN
1 HEALTH VIOLATIONS
Merrillville, IN Water Quality Report
1 ZIP code · 3 water systems · Updated 2026-03-16
Data: EPA SDWIS Last verified: 2026-03-16
1
ZIP Codes
3
Water Systems
1
ZIPs with Violations
Zone 1
Radon Risk (High)
Overview
We track water quality and home safety data for 1 ZIP code in Merrillville, Indiana, covering 3 community water systems serving approximately 4,200 people.
1 of 1 ZIP code (100%) have recorded EPA violations. 1 health-based violation documented.
Water Sources
Merrillville water systems draw from: Groundwater, Surface water.
Lead & Copper
- Lead data: not yet available for Merrillville
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Consumer Confidence Report Rule | Reporting | 10 | 1 |
| Gross Alpha | Radionuclides | 6 | 1 |
| Radium-226 | Radionuclides | 6 | 1 |
| Radium-228 | Radionuclides | 6 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 46410 | — | 14 | 1 | CUII - INDIANA WATER SERVICE |
All ZIP Codes in Merrillville
- 46410 — 14 violations ⚠
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.