Is Merrillville, IN tap water safe?
Data: U.S. EPA · How we read the data · How we check it
Summary
No federal limits exceeded in EPA data for Indiana American Water – Northwest.
3 public water systems serve parts of Merrillville. The largest, Indiana American Water – Northwest, serves 210,510 people. Your water bill names your system.
Largest system
Indiana American Water – Northwest
210,510 people · Surface water · EPA ID IN5245015
| PFAS | Highest average | Limit |
|---|---|---|
| PFOA Not detected | – | 4 ppt |
| PFOS Not detected | – | 4 ppt |
| PFHxS Not detected | – | 10 ppt |
| PFNA Not detected | – | 10 ppt |
| HFPO-DA (GenX) Not detected | – | 10 ppt |
ppt = parts per trillion. "Highest average" is the highest average at any of the system's entry points, the way EPA compares results with the limits.
Lead: 3 ppb at the 90th percentile (Dec 2024, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0
Across Indiana, 6 of 219 water systems EPA tested had PFAS above a 2024 federal limit, and 6 systems were above the lead action level in results from the last five years. Indiana results.
Merrillville homes and lead pipes
Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. How to check your own line.
Housing: Census American Community Survey 2020–2024 5-year estimates for Merrillville town (tables B25034, B25003). Estimates for small places have a margin of error.
Other water systems serving Merrillville
- Crossings Mobile Home Park Water System100 people · Groundwater · Indiana · lists this cityColiform bacteria violation
- Rockwell Shores Apartments45 people · Groundwater · Indiana · lists this cityNot in EPA's PFAS sample
How nearby cities compare
| City | PFAS | Lead (90th pct.) |
|---|---|---|
| Hobart 4 mi Indiana American Water – Northwest | None above limits | 3 ppb |
| Crown Point 4 mi Crown Point Water Works | None above limits | 0.7 ppb |
| Schererville 7 mi Schererville Water Department | None above limits | 1 ppb |
| Gary 9 mi Indiana American Water – Northwest | None above limits | 3 ppb |
| Hammond 14 mi Hammond Water Works Department | None above limits | 3 ppb |
| Valparaiso 14 mi Valparaiso Department of Water Works | None above limits | 3.7 ppb |
Merrillville ZIP codes (1)
- 46410
Questions
Is Merrillville tap water safe to drink?
Indiana American Water – Northwest has had no health-based violations since 2016. Utility data can't show lead from your own pipes: if your home was built before 1986, test your tap. Your utility's annual Consumer Confidence Report is the official summary.
Who supplies water in Merrillville, IN?
3 public water systems serve parts of Merrillville. The largest is Indiana American Water – Northwest (210,510 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.
Does Merrillville tap water have PFAS?
None detected above EPA's reporting limits. Indiana American Water – Northwest had no PFAS detected in EPA's 2023–2025 testing. "Not detected" means below the reporting limit (about 2 to 20 ppt), not proven zero.
Do Merrillville homes have lead pipes?
Census estimates put 52% of Merrillville homes as built before 1980 (Indiana: 55%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Indiana American Water – Northwest's service line inventory says what your line is made of. The only way to know for your home is to check the line where it enters the house and test your tap.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.