Updated 2026-10-15
County water report

Boone County Water Quality

Boone County, Illinois: one city report built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.

Across the county's systems

Highest result for each contaminant

One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.

Perfluorohexanesulfonic acid (PFHxS)BELVIDERE10 ng/L federal MCL (2024) · US EPA5.5 ng/L
  • BELVIDERE5.5 ng/LSample date: 2024-09-19 to 2025-03-25
Lead (90th percentile)BELVIDERE15 µg/L federal action level · US EPA1.8 µg/L
  • BELVIDERE1.8 µg/LMonitoring period: 2026–2028 (still open)
29 substances tested, none detected in this systemShow

Tested in this system: BELVIDERE

  • 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
  • 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
  • 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
  • 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
  • 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
  • 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
  • Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
  • Lithium
  • N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
  • N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
  • Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
  • Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
  • Perfluoro-3-methoxypropanoic acid (PFMPA)
  • Perfluoro-4-methoxybutanoic acid (PFMBA)
  • Perfluorobutanesulfonic acid (PFBS)
  • Perfluorobutanoic acid (PFBA)
  • Perfluorodecanoic acid (PFDA)
  • Perfluorododecanoic acid (PFDoA)
  • Perfluoroheptanesulfonic acid (PFHpS)
  • Perfluoroheptanoic acid (PFHpA)
  • Perfluorohexanoic acid (PFHxA)
  • Perfluorononanoic acid (PFNA)
  • Perfluorooctanesulfonic acid (PFOS)
  • Perfluorooctanoic acid (PFOA)
  • Perfluoropentanesulfonic acid (PFPeS)
  • Perfluoropentanoic acid (PFPeA)
  • Perfluorotetradecanoic acid (PFTA)
  • Perfluorotridecanoic acid (PFTrDA)
  • Perfluoroundecanoic acid (PFUnA)
1 city

Cities ranked by the records

Showing 1 of 1 cities · scores are system-level, not tap tests

Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.

PFAS in Boone CountyPFAS detected in 1 of 1 city; none had a sample above a 2024 EPA limit
4.0 ng/L federal MCL · PFOS, ng/LPFAS in Illinois
Lead

0of 1 city above the 15 µg/L action level

Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.

Lead in Illinois
Who supplies the county

Largest water systems

  1. BelvidereBELVIDERE · IL0070050
    25,339 served
Questions

Frequently asked

How does Boone County tap water compare across cities?

PurityMap ranks 1 city in Boone County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Belvidere's main water system: BELVIDERE · PWSID IL0070050 · Purity Score 88 (Good) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.

How many Boone County cities had a PFAS sample above a 2024 EPA limit?

None of the 1 Boone County city report had a PFAS sample above a 2024 EPA limit in EPA's UCMR 5 testing. PFAS were detected below the limit in 1.

Is there lead in Boone County tap water?

Utilities report lead as a 90th-percentile result from home taps. 1 of 1 Boone County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.

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