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Tap water quality report

City of Gridley

EPA monitoring tested this supplier for 86 contaminants and detected 20. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

86
contaminants tested
20
detected
7,269
people served
7
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Local government
Counties served
Butte

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

7
health-based violations
10
violations on file
2
still open
ViolationTypeStatusPeriod
TT Health-based Unaddressed 2024-10-17
MCL Health-based Resolved 2008-10-01 → 2008-12-31
MCL Health-based Resolved 2008-10-01 → 2008-12-31
MCL Health-based Resolved 2007-07-01 → 2007-09-30
MCL Health-based Resolved 2007-07-01 → 2007-09-30
MCL Health-based Resolved 1999-03-01 → 1999-03-31
MCL Health-based Resolved 1999-03-01 → 1999-03-31
RPT Monitoring Unaddressed 2024-10-17
MR Monitoring Resolved 2002-01-01 → 2002-12-31
MR Monitoring Resolved 2002-01-01 → 2002-12-31

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfhpa 0.0035 µg/L 2/10 2024
Pfhxa 0.0053 µg/L 2/10 2024
PFHXS 0.0128 µg/L 2/10 2024
PFNA 0.0099 µg/L 2/10 2024
PFOS 0.0105 µg/L 2/10 2024
Pfpea 0.0065 µg/L 2/10 2024

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Fluoride
1180 µg/L 30%
of the EPA limit 4000 µg/L
worst single sample: 1400 µg/L
105/116 SYR4 2012–2019
Nitrate
3300 µg/L 33%
of the EPA limit 10000 µg/L
worst single sample: 5200 µg/L
92/94 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 22/22 LCR 2023
Arsenic
13.93 µg/L 139%
of the EPA limit, at the 95th percentile of samples — 10 µg/L
worst single sample: 14.2 µg/L
19/19 SYR4 2012–2019
Barium
65.125 µg/L 3.3%
of the EPA limit 2000 µg/L
worst single sample: 69.5 µg/L
8/10 SYR4 2012–2019
Nitrite
260 µg/L 26%
of the EPA limit 1000 µg/L
 6/17 SYR4 2012–2019
TTHM
5.525 µg/L 6.9%
of the EPA limit 80 µg/L
worst single sample: 5.9 µg/L
4/7 SYR4 2014–2019
Bromoform
5.47 µg/L
No EPA limit set
worst single sample: 5.9 µg/L
3/7 SYR4 2014–2019
Chromium
10.9 µg/L 11%
of the EPA limit 100 µg/L
worst single sample: 11 µg/L
3/9 SYR4 2013–2019
Bromodichloromethane
0.9900 µg/L
No EPA limit set
worst single sample: 1 µg/L
2/7 SYR4 2014–2019
Dibromoacetic Acid
1 µg/L
No EPA limit set
 2/6 SYR4 2014–2019
Dibromochloromethane
1 µg/L
No EPA limit set
 2/7 SYR4 2014–2019
Total Haloacetic Acids (HAA5)
1 µg/L 1.7%
of the EPA limit 60 µg/L
 2/6 SYR4 2014–2019
Nitrate-Nitrite
1400 µg/L 14%
of the EPA limit 10000 µg/L
 1/1 SYR4 2018
66 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAtrazineBenzeneBeryllium, TotalChlorobenzeneCopperCadmiumCarbofuranCarbon TetrachlorideChloroformDichloromethaneDichloroacetic AcidDinosebDiquatEndothallEthylbenzeneGlyphosateHfpo-DaLeadMercuryMonobromoacetic AcidMonochloroacetic AcidNetfosaaNfdhaNmefosaaPfbaPFBSPfdaPfdoaPfeesaPfhpsPfmbaPfmpaPFOAPfpesPftaPftrdaPfunaSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
TANABE, JACOB
Phone
530-846-5695
Email
[email protected]

Frequently asked questions about City of Gridley

Is City of Gridley tap water safe to drink?

EPA monitoring detected 20 contaminants in City of Gridley's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in City of Gridley's water?

EPA monitoring detected Fluoride, Nitrate, Lead, Arsenic, Barium, and others. The full list with the level and data source for each is above.

How many people does City of Gridley serve?

City of Gridley reports serving 7,269 people in California, per its EPA record.

Has City of Gridley had any water quality violations?

The EPA has 10 violations on file for City of Gridley, of which 7 are health-based (a contaminant limit or required treatment was breached) and 2 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.