Is DeKalb, 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 DeKalb Water System.
DeKalb Water System supplies DeKalb (40,290 people).
Water system
DeKalb Water System
40,290 people · Groundwater · EPA ID IL0370100
| 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: 13 ppb at the 90th percentile (Jun 2026, and 9 in 10 homes sampled were at or below it) Near 2027 action level
Health-based violations since 2016: 0
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.
DeKalb homes and lead pipes
Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. Renting? Ask your landlord what the service line is made of, because it's their pipe to replace. How to check your own line.
Housing: Census American Community Survey 2020–2024 5-year estimates for DeKalb city (tables B25034, B25003). Estimates for small places have a margin of error.
How nearby cities compare
| City | PFAS | Lead (90th pct.) |
|---|---|---|
| St. Charles 22 mi St Charles Water System | None above limits | 3.9 ppb |
| Huntley 23 mi Huntley Water System | None above limits | 1.1 ppb |
| South Elgin 23 mi South Elgin Water System | Above limit | 1.4 ppb |
| Elgin 23 mi Elgin Water System | None above limits | 18.5 ppb |
| Batavia 23 mi Batavia Water System | None above limits | 3.82 ppb |
| Belvidere 24 mi Belvidere Water System | None above limits | 1.8 ppb |
DeKalb ZIP codes (1)
- 60115
Questions
Is DeKalb tap water safe to drink?
DeKalb Water System 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 DeKalb, IL?
DeKalb Water System, which serves 40,290 people.
Does DeKalb tap water have PFAS?
None detected above EPA's reporting limits. DeKalb 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 DeKalb homes have lead pipes?
Census estimates put 59% of DeKalb 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. DeKalb 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.