Tap Water Results

Is Oswego, IL 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 Oswego Water System.

Oswego Water System supplies Oswego (38,169 people).

Water system

Oswego Water System

38,169 people · Groundwater · EPA ID IL0930150

PFASHighest averageLimitStatus
PFOA
Not detected
–4 pptNot detected
PFOS
Not detected
–4 pptNot detected
PFHxS
Not detected
–10 pptNot detected
PFNA
Not detected
–10 pptNot detected
HFPO-DA (GenX)
Not detected
–10 pptNot detected

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: 0 ppb at the 90th percentile (Dec 2025, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 1

Across Illinois, 13 of 479 water systems EPA tested had PFAS above a 2024 federal limit, and 18 systems were above the lead action level in results from the last five years. Illinois results.

Oswego homes and lead pipes

11%
of homes built before 1980 (Illinois 64%, US 50%)
4%
built before 1950 (Illinois 26%)
12%
of households rent (Illinois 33%)

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 Oswego village (tables B25034, B25003). Estimates for small places have a margin of error.

How nearby cities compare

CityMain water systemPFASLead (90th pct.)
Yorkville 5 mi
Yorkville Water System
Yorkville Water SystemNone above limits1.45 ppb
Plainfield 6 mi
Plainfield Water System
Plainfield Water SystemNone above limits0 ppb
Aurora 6 mi
Aurora Water System
Aurora Water SystemNone above limits25.7 ppb
Naperville 10 mi
Naperville Water System
Naperville Water SystemNone above limits6.1 ppb
Batavia 11 mi
Batavia Water System
Batavia Water SystemNone above limits3.82 ppb
Bolingbrook 12 mi
Illinois American Water – West Suburban
Illinois American Water – West SuburbanNone above limits0 ppb
Oswego ZIP codes (1)
  • 60543

Questions

Is Oswego tap water safe to drink?

Oswego Water System had 1 health-based violation 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 Oswego, IL?

Oswego Water System, which serves 38,169 people.

Does Oswego tap water have PFAS?

None detected above EPA's reporting limits. Oswego Water System 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 Oswego homes have lead pipes?

Census estimates put 11% of Oswego homes as built before 1980 (Illinois: 64%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Oswego Water System'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.