WaterVerge

Is Trabuco Canyon, CA Tap Water Safe to Drink?

Graded A- — but Chlorate was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

14K residents served 1 water system PWSID: CA3010094
Overall Score
88.2 / 100
Violations
2 active
Last Updated
May 2026
Source
Purchased surface water
#195 of 694 in California Top 23% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
88.2/100
waterverge.com
A- 88.2/100

Trabuco Canyon, CA — Water Quality Report

Trabuco Canyon's drinking water received a grade of A- (88.2 out of 100), indicating good water quality. The city's 1 water system serves approximately 13,659 residents using purchased surface water.

Lead levels were measured at 3.9 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 5 violations on record, including 2 health-based violations. 2 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Trabuco Canyon's water

Trabuco Canyon ranks #195 out of 694 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.04 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.

Quality Breakdown

Water quality score

See methodology →
88.2 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
44.2/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 3.9 ppb (90th percentile).
Contaminants
16.9/20
B
1 PFAS compound detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Trabuco Canyon, CA water safe to drink?

Use Caution

Trabuco Canyon's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (88.2/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 13,659 residents using surface water (rivers, lakes, or reservoirs).

2
Active Violations
3.9 ppb
Lead (90th %ile)
1 compound
PFAS Detected
10 events
Disaster History

Recent water quality updates for Trabuco Canyon

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Trabuco Canyon's water quality assessment. Grade: A- (88.2/100).

Disaster
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.

Disaster
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES

Federal disaster declaration (FEMA DR-3591). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Surface Water Treatment Rule.

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Key contaminant findings

Based on the most recent EPA sampling data for Trabuco Canyon's water supply.

Lead Within Limits
Detected: 3.9 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 65.9000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Trabuco Canyon's water system has 5 total violations on record, including 2 health-based violations. 2 remain unresolved.

TTMRMCL
Most recent violations:
Jan 1999 Surface Water Treatment Rule Open
Sep 1997 Coliform (TCR) Resolved
Aug 1997 Coliform (TCR) Resolved
Nov 1996 Coliform (TCR) Resolved

Flood & environmental risk

Orange County has experienced 10 federally declared disasters since 1980. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Agua Chinon Wash A Portola Springs Rd Nr Irvine, Coldwater Canyon C Nr Corona, Temescal C A Corona Lk Nr Corona, Santiago C A Modjeska.

SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-3592
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-3591
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-4305

Where does Trabuco Canyon's water come from?

Trabuco Canyon's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 13,659 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Agua Chinon Wash A Portola Springs Rd Nr Irvine (river), Coldwater Canyon C Nr Corona (river), Temescal C A Corona Lk Nr Corona (river), Santiago C A Modjeska (river).

What Trabuco Canyon residents can do

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Trabuco Canyon's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
3.9 ppb
EPA Action Level: 15 ppb · 26% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
65.9000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
10.5 µg/L
EPA MCL: 60 µg/L · 18% of limit
Within LimitUCMR 4 DataHAA6Br: 9.3 µg/LHAA9: 18.5 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.04 µg/L
CA MCL (no federal MCL): 10 µg/L · 0% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Elevated
1000.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 67% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
0.6 µg/L
EPA Secondary MCL: 50 µg/L · 1% of limit
DetectedUCMR 4 Data
Perchlorate
Inorganic
Elevated
5.00 µg/L
CA MCL (no federal MCL): 6 µg/L · 83% of limit
DetectedUCMR 1 Data (2001–2005)
Vanadium
Inorganic
Detected
3.60 µg/L
EPA Short-term HA: 21 µg/L · 17% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
290.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Molybdenum
Inorganic
Detected
5.20 µg/L
EPA Lifetime HA: 40 µg/L · 13% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Above state screening
65.9 µg/L
State screening level: 60 µg/L · +10% over limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

5
Total violations
2
Health-based
2
Active / unresolved
Jan 1999
Most recent violation
Compliance Record

Violations & advisories

5 Total
2 Active
2 Health-based
3 Resolved
Violations by category
Total Coliform Rule
3
Surface Water Treatment Rule
1
Jan 1999 Active
Surface Water Treatment Rule
Treatment Technique
Health-Based Health 0
Active
Compliance Violation
Monitoring 0
Sep 1997 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1997
Aug 1997 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 1997
Nov 1996 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1996
Industrial pollution

Top industrial polluters within 10 miles of Trabuco Canyon

Industrial polluters nearby

Reported releases to surface water by facilities near Trabuco Canyon, ranked by pounds discharged annually.

Total reported releases to surface water: 0 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
DYNACAST INC
Primary Metals · FORM TECHNOLOGIES
LAKE FOREST, CA92630
Copper04.9 mi
OAKLEY INC
Miscellaneous Manufacturing · ESSILORLUXOTTICA USA INC
FOOTHILL RANCH, CA92610
2.9 mi
APPLIED MEDICAL RESOURCES CORP
Miscellaneous Manufacturing · APPLIED MEDICAL RESOURCES CORP
IRVINE, CA92618
7.1 mi
ROBERTSON'S READY MIX LAKE FOREST PLANT 18
Nonmetallic Mineral Product · MCC DEVELOPMENT CORP
FOOTHILL RANCH, CA92610
4.8 mi
SDC TECHNOLOGIES INC
Chemicals · NA
IRVINE, CA92618
6.4 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Trabuco Canyon

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

10
Declared disasters
Mar 2023
Most recent
Flood
Most common type

Orange County has experienced 10 federally declared disasters since 1980. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Mar 2023
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #3592
Jan 2023
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #3591
Mar 2017
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #4305
Jan 2011
SEVERE WINTER STORMS, FLOODING, AND DEBRIS AND MUD FLOWS
Flood FEMA #1952
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3248
Feb 1993
SEVERE WINTER STORM, MUD & LAND SLIDES, & FLOODING
Flood FEMA #979

Recommended water filters

Based on contaminants detected in Trabuco Canyon's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 3.9 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 65.900 HI µg/L PFAS 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.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has increased by 1.4 ppb from 1992 (2.5 ppb) to 2024 (3.9 ppb).
Contaminant Rankings

See how Trabuco Canyon compares by contaminant

Explore where Trabuco Canyon ranks among all California cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
13,659
Water Systems
1
Water Source

Where Trabuco Canyon's water comes from

Purchased Surface Water

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

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 13,659 people through 1 water system.

Local Hydrology

Water bodies near Trabuco Canyon

Trabuco Canyon is located near 4 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Agua Chinon Wash A Portola Springs Rd Nr Irvine
river
Coldwater Canyon C Nr Corona
river
Temescal C A Corona Lk Nr Corona
river
Santiago C A Modjeska
river
Infrastructure

Water systems serving Trabuco Canyon

System Name PWSID Population Source
TRABUCO CANYON WATER DISTRICT CA3010094 13,659 SWP
Regional Comparison

How Trabuco Canyon compares

Full California rankings →

Trabuco Canyon's score of 88.2/100 is above the average of 57/100 among major California cities. It outscores 8 of 10 nearby cities.

Trabuco Canyon (this city)
88.2
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About Trabuco Canyon, CA

Wikipedia →

Trabuco Canyon is a small unincorporated community and census-designated place (CDP) located in the foothills of the Santa Ana Mountains in eastern Orange County, California, and lies partly within the Cleveland National Forest.

Economic Profile
$163,750
Median Income
$1,120,176
Median Home Value
4.1%
Unemployment
Community
54.4
Median Age
68
People / sq mi
59.1%
College Educated
95.5%
Homeownership
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Frequently asked questions

Is Trabuco Canyon, CA tap water safe to drink?

Trabuco Canyon's water quality earned a grade of A- (88.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #195 out of 694 cities tested in California.

What contaminants are in Trabuco Canyon's water?

Lead was measured at 3.9 ppb (90th percentile). 1 PFAS compound was detected. 5 violations are on record.

How is Trabuco 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 Trabuco Canyon?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Trabuco Canyon's water come from?

Trabuco Canyon's water is sourced from Purchased surface water. The city has 1 water system serving approximately 13,659 residents.

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

Trabuco Canyon has 2 health-based violations on record. The most recent violation was recorded in January 1999. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.

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

Trabuco Canyon ranks #195 out of 694 cities in California (better than 72% of state cities) and #3569 out of 15744 cities nationally (77th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.