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WaterVerge

Water quality report · updated Jul 2026

Is American Canyon, CA Tap Water Safe to Drink?

Graded A-, with 1 unresolved violation on record. See what was cited — and what it means for your tap. What to do ↓

0 contaminants over a legal limit
0.0 ppb lead, 90th percentile · low
1 unresolved violation
21K people served by 1 water system

PWSID CA2810005 · high data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
A 85.5 / 100

#256 of 690California cities
How we grade →

01The verdict: is American Canyon water safe?

American Canyon's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (85.5/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 21,437 residents using surface water (rivers, lakes, or reservoirs).

The concern

1 unresolved violation on record

EPA records show an open compliance item for this system. Most are administrative, but unresolved items are worth watching.

See what was cited ↓
The good news

Lead is well under the limit

90th-percentile lead is 0.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

Manganese is approaching its limit

Measured at 37.0 µg/L — 74% of the 50 µg/L limit. Within the rules, but with less headroom than you'd want.

See the ledger ↓

American Canyon's drinking water received a grade of A- (85.5 out of 100), indicating good water quality. The city's 1 water system serves approximately 21,437 residents using surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals. The system has 17 violations on record, including 15 health-based violations. 1 remains unresolved.

American Canyon ranks #256 out of 690 cities in California for water quality, placing it mid-range in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. Haloacetic acid (HAA5) levels were elevated at 36.0 µg/L in UCMR 4 testing, though below the 60 µg/L EPA limit. Activated carbon filtration can help reduce these disinfection byproducts. Hexavalent chromium (chromium-6) was detected at 0.09 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

How the 85.5/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
35.7 / 45B
Lead & CopperLead at 0.0 ppb (90th percentile).
20 / 20A
ContaminantsNo PFAS compounds detected.
17.8 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Surface water.
4 / 5B

02What's in American Canyon's water

Every contaminant flagged in American Canyon, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.

8 detections · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%
Manganese Inorganic
37.0 µg/L 74% of limit
Chlorate Disinfection Byproduct
120.0 µg/L 57% of limit
Vanadium Inorganic
4.00 µg/L 19% of limit
Strontium Inorganic
200.0 µg/L 13% of limit
Molybdenum Inorganic
1.40 µg/L 3% of limit
38 contaminants tested under EPA SDWIS, LCR and UCMR programs · 8 detected Contaminants without a federal MCL are shown against the strictest state or advisory level named in each row.

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium ND HI µg/L PFAS Not Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03American Canyon's ten-year track record

Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 17 violations on record, including 15 health-based violations. 1 remains unresolved.

7 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.

9 health-based in 10 yrs 1 monitoring & paperwork 1 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into American Canyon's water quality assessment. Grade: A- (85.5/100).
DisasterSEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDESFederal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.
DisasterSEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDESFederal disaster declaration (FEMA DR-4683). Flood event — may have impacted local water infrastructure.
Violation1 drinking water violation recordedContaminants: Lead and Copper Rule.Open
Violation2 drinking water violations recorded2 health-based. Contaminants: TTHM.Resolved
Violation3 drinking water violations recorded3 health-based. Contaminants: TTHM.Resolved
Lead, 90th percentileppb · lower is better
05101520EPA action level · 15 ppb1992 — 2.5 ppb1993 — 3 ppb1994 — 4 ppb1998 — 1 ppb1999 — 4 ppb2000 — 1.9 ppb2002 — 1.4 ppb2003 — 1.9 ppb2005 — 1.9 ppb2008 — 1 ppb2011 — 1.4 ppb2014 — 1.1 ppb2017 — 0 ppb2024 — 0 ppb2.50199219982002200820172024

Down 2.5 ppb since 1992. Latest reading: 0 ppb (2024) — 0% of the action level. Sampled at higher-risk homes (90th percentile).

04Where American Canyon's water comes from

American Canyon's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Surface Water

Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.

Treatment

Local treatment

Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.

Distribution

1 system

1 water system, operated under local government ownership.

Delivery

21,437 people

Residents served across American Canyon's service area.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 21,437 people through 1 water system.

System namePWSIDPopulationSource
AMERICAN CANYON, CITY OF CA2810005 21,437 Surface Water

05Pressure on American Canyon's watershed

Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.

Industrial discharge

Moderate — reported releases upstream

5 facilities within 10 miles reported 770k lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.

PHILLIPS 66 RODEO RENEWABLE ENERGY COMPLEX — nitrate compounds (water dissociable; reportable only when in aqueous solution) 529k lb · 9.0 mi
VALERO REFINING CO-CALI FORNIA BENICIA REFINERY — nitrate compounds (water dissociable; reportable only when in aqueous solution) 241k lb · 9.6 mi
FOLEY PRODUCTS CO - NAPA 0 lb · 2.2 mi
+ 2 more facilities

Flood & storm history

Recurring — declared disasters

10 federal disaster declarations on record for Napa County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.

SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES Mar 2023 · DR-3592
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES Jan 2023 · DR-4683
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES Jan 2023 · DR-3591

06How American Canyon compares

Scores for nearby California cities on one line, with the average marked.

American Canyon (this city)
85.5 · A-
Oakland
77.9 · B
Los Angeles
42.8 · F
San Diego
39.7 · F
Sacramento
31.2 · F
San Jose
28 · F

dashed line = California average (57/100)

American Canyon scores 85.5/100above the California average of 57/100. It outscores 8 of 10 nearby cities. Full California rankings →

Napa water quality rankings
Compare all cities in the county — grades, violations, and contaminant data side by side.

07What to do at home

Steps matched to what testing actually found in American Canyon's water — not generic advice.

Extra protection

A basic carbon filter still helps

American Canyon's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.

Compare tested filters →
Know your report

Read your utility's annual report

Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.

How to read a CCR →
Stay informed

Watch for American Canyon alerts

This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.

All water alerts →

Frequently asked questions

Is American Canyon, CA tap water safe to drink?

American Canyon's water quality earned a grade of A- (85.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #256 out of 690 cities tested in California.

What contaminants are in American Canyon's water?

Lead was measured at 0.0 ppb (90th percentile). No PFAS compounds were detected. 17 violations are on record.

How is American Canyon's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in American Canyon?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does American Canyon's water come from?

American Canyon's water is sourced from Surface water. The city has 1 water system serving approximately 21,437 residents.

What health violations has American Canyon's water system had?

American Canyon has 15 health-based violations on record. The most recent violation was recorded in October 2020. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 1 violation remains unresolved.

How does American Canyon's water compare to other cities?

American Canyon ranks #256 out of 690 cities in California (better than 63% of state cities) and #5221 out of 15382 cities nationally (66th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

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About American Canyon, CA: Median household income $122,694 · median home value $615,587 · median age 36.2 · 79% homeowners · 34% college educated. Service area: 1 ZIP code across Napa.
Show ZIP codes 94503
Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.