Fresno County, California has about 1,024,125 residents (Census 2024 estimate) and 102 community water systems in EPA records. The largest local system is City of Fresno, serving about 545,970 people from surface water.
! 2 of 6 largest systems with health-based violationsPFAS detected at 3 of 6 sampled systemsHardness 7.5 gpg (high 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 Fresno County water?
City of FresnoMeasured (utility report, 2025) · High 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.
Softener size at 7.5 gpg
For a 3-person home using 57 gallons per person per day and regenerating weekly, you'd remove about 8,978 grains between regenerations. Suggested size: 24,000 grain.
Estimate only. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
The 6 biggest of 102 community water systems on EPA records for this county. Service areas don't follow county lines; your water bill names your provider.
City of Fresno
CA1010007 · serves about 545,970 people · Surface water
✓ No health-based violations✓ Lead below detectionPFAS detected (10 types)
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2023-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFPeA: highest sample 47 ppt (39 of 339 samples); no federal limit
PFHxA: highest sample 34 ppt (31 of 339 samples); no federal limit
PFHpA: highest sample 31 ppt (13 of 339 samples); no federal limit
PFHxS: highest sample 30 ppt (22 of 339 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFOS: highest sample 30 ppt (43 of 339 samples); federal limit 4.0 ppt as a running annual average
PFBA: highest sample 26 ppt (5 of 339 samples); no federal limit
PFOA: highest sample 16 ppt (36 of 339 samples); federal limit 4.0 ppt as a running annual average
PFBS: highest sample 8.6 ppt (16 of 339 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFNA: highest sample 8 ppt (6 of 339 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFPeS: highest sample 5.3 ppt (2 of 339 samples); no federal limit
CA1010003 · serves about 133,118 people · Surface water
✓ No health-based violations✓ Lead below detectionPFAS detected (10 types)
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2022-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFOS: highest sample 41 ppt (8 of 78 samples); federal limit 4.0 ppt as a running annual average
PFOA: highest sample 18 ppt (9 of 78 samples); federal limit 4.0 ppt as a running annual average
PFHxS: highest sample 8.8 ppt (4 of 78 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFPeA: highest sample 8.4 ppt (3 of 78 samples); no federal limit
PFHxA: highest sample 8 ppt (6 of 78 samples); no federal limit
PFBS: highest sample 7.9 ppt (10 of 78 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFNA: highest sample 6.9 ppt (2 of 78 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFBA: highest sample 6.1 ppt (1 of 78 samples); no federal limit
PFHpA: highest sample 5.7 ppt (2 of 78 samples); no federal limit
PFDA: highest sample 3.1 ppt (2 of 78 samples); no federal limit
CA1010029 · serves about 26,357 people · Groundwater
! 1 health-based violation✓ Lead below detectionPFAS detected (4 types)
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2023-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFOS: highest sample 6.7 ppt (2 of 19 samples); federal limit 4.0 ppt as a running annual average
PFOA: highest sample 5.6 ppt (2 of 19 samples); federal limit 4.0 ppt as a running annual average
PFPeA: highest sample 5.1 ppt (2 of 19 samples); no federal limit
PFHxA: highest sample 4.7 ppt (2 of 19 samples); no federal limit
CA1010027 · serves about 26,076 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 2022-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
CA1010024 · serves about 25,651 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 2023-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
CA1010001 · serves about 17,393 people · Groundwater
! 1 health-based violation✓ Lead below detection✓ No PFAS detected
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2023-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
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 Fresno County water
Is tap water in Fresno County safe to drink?
2 of the 6 largest systems here have at least one health-based violation in EPA records since October 2021 (see each system below for status). City of Fresno's most recent lead 90th percentile was below the lab detection limit (2023), below the 15 ppb action level. 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 Fresno County?
City of Fresno reports about 7.5 grains per gallon (129 mg/L), which is hard. For a 3-person home at 7.5 gpg, our softener calculator suggests a 24,000 grain unit as a starting point.
Is there PFAS in Fresno County water?
3 of the 6 sampled systems listed here detected at least one PFAS in EPA's UCMR 5 testing, and 7 results were above the level of a federal limit in at least one sample. A detection isn't a violation: federal PFAS limits apply to running annual averages starting in 2029.
Which water system serves my address in Fresno County?
Most homes are served by City of Fresno 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.
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.