Kane County tap water: hardness, PFAS and lead

Kane County, Illinois has about 520,997 residents (Census 2024 estimate) and 39 community water systems in EPA records. The largest local system is Aurora, serving about 183,000 people from surface water.

✓ 0 of 6 largest systems with health-based violationsPFAS detected at 3 of 6 sampled systemsHardness 18.2 gpg (low confidence)

Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.

How hard is Kane County water?

Aurora Estimate: untreated local water, not your tap · Low confidence

18.2 gpg (311 mg/L), very hard

Kane County: median of 1,019 results from 101 monitoring sites (streams and wells). Utilities may blend or treat water, so your tap can differ.

Source: Hard Water Map county data, samples through 2022

County estimates: Hard Water Map (hardwatermap.com), CC BY 4.0, derived from the USGS/EPA Water Quality Portal; file generated 2026-07-22. License

Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.

Softener size at 18.2 gpg

For a 3-person home using 57 gallons per person per day and regenerating weekly, you'd remove about 21,785 grains between regenerations. Suggested size: 24,000 grain. This uses a low-confidence county estimate, so confirm with a test first.

Estimate only. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.

Open the softener calculator with 18.2 gpg

Largest water systems in Kane County

The 6 biggest of 39 community water systems on EPA records for this county. Service areas don't follow county lines; your water bill names your provider.

Aurora

IL0894070 · serves about 183,000 people · Surface water

✓ No health-based violations! Lead above action levelPFAS detected (4 types)

Lead 90th percentile: 25.7 ppb (period starting 2026-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

  • PFBA: highest sample 5.9 ppt (2 of 4 samples); no federal limit
  • PFPeA: highest sample 5.3 ppt (3 of 4 samples); no federal limit
  • PFHxA: highest sample 4.7 ppt (3 of 4 samples); no federal limit
  • PFBS: highest sample 3.7 ppt (2 of 4 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit

EPA ECHO record

Elgin

IL0894380 · serves about 114,797 people · Surface water

✓ No health-based violations! Lead above action levelPFAS detected (3 types)

Lead 90th percentile: 18.5 ppb (period starting 2026-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

  • PFBA: highest sample 7.6 ppt (1 of 8 samples); no federal limit
  • PFPeA: highest sample 4.7 ppt (3 of 8 samples); no federal limit
  • PFHxA: highest sample 4 ppt (3 of 8 samples); no federal limit

EPA ECHO record

Carpentersville

IL0890200 · serves about 37,983 people · Groundwater

✓ No health-based violations✓ Lead below action level✓ No PFAS detected

Lead 90th percentile: 1.1 ppb (period starting 2026-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

EPA ECHO record

St Charles

IL0894830 · serves about 33,081 people · Groundwater

✓ No health-based violations✓ Lead below action levelPFAS detected (3 types)

Lead 90th percentile: 3.9 ppb (period starting 2026-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

  • PFPeA: highest sample 7.5 ppt (1 of 10 samples); no federal limit
  • PFBS: highest sample 6.2 ppt (3 of 10 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
  • PFHxA: highest sample 5.3 ppt (1 of 10 samples); no federal limit

EPA ECHO record

Montgomery

IL0894690 · serves about 28,956 people · Groundwater

✓ No health-based violations✓ Lead below detection✓ No PFAS detected

Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2025-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

EPA ECHO record

Batavia

IL0894130 · serves about 26,098 people · Groundwater

✓ No health-based violations✓ Lead below action level✓ No PFAS detected

Lead 90th percentile: 3.8 ppb (period starting 2025-07-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).

EPA ECHO record

Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.

A PFAS detection is not a violation. Federal limits (4 ppt for PFOA and PFOS) apply to running annual averages, with compliance required by 2029. In May 2026 EPA proposed extending the PFOA/PFOS deadline to 2031 and removing other PFAS limits; not final as of 2026-10-21.

Test your own tap

These are public records for whole systems. Your home's pipes, fixtures and any private well can change what you drink. A certified lab test or a hardness test strip gives you your own numbers. Then use our PFAS and lead filter selector to see which certifications to look for.

Common questions about Kane County water

Is tap water in Kane County safe to drink?

None of the 6 largest systems here have a health-based violation in EPA records since October 2021. Aurora's most recent lead 90th percentile (25.7 ppb, from 2026) was above the federal action level, which requires steps like corrosion control and public education. Public records can't guarantee what comes out of your tap, especially with older plumbing, so a home test is the surest check.

How hard is the water in Kane County?

There's no published utility figure in our data, but untreated local stream and well samples in Kane County have a median of about 18.2 grains per gallon (311 mg/L, very hard). That's a low-confidence estimate of source water, not your tap, so test before you buy equipment. For a 3-person home at 18.2 gpg, our softener calculator suggests a 24,000 grain unit as a starting point.

Is there PFAS in Kane County water?

3 of the 6 sampled systems listed here detected at least one PFAS in EPA's UCMR 5 testing. A detection isn't a violation: federal PFAS limits apply to running annual averages starting in 2029.

Which water system serves my address in Kane County?

Most homes are served by Aurora or one of the other systems listed on this page, but service areas don't follow county lines. Your water bill names your provider, and its annual Consumer Confidence Report has the full test results.

More Illinois counties

Sources for this page

Data as of October 21, 2026. Figures are copied from public records and combined with our own calculations; they can be out of date or wrong. Tapped Out isn't affiliated with any utility or the EPA. Written and reviewed by the Tapped Out team. How we calculate · All sources.