WaterVerge

Is South Pasadena, CA Tap Water Safe to Drink?

Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

25K residents served 2 water systems PWSID: CA1910154
Overall Score
90.5 / 100
Violations
2 active
Last Updated
May 2026
Source
Purchased surface water
#124 of 694 in California Top 14% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
AGRADE
Water Quality Grade
90.5/100
waterverge.com
A 90.5/100

South Pasadena, CA — Water Quality Report

South Pasadena's drinking water received a grade of A (90.5 out of 100), indicating excellent water quality. The city's 2 water systems serve approximately 25,389 residents using purchased 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 14 violations on record, including 5 health-based violations. 2 remain unresolved.

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

What to know about South Pasadena's water

South Pasadena ranks #124 out of 694 cities in California for water quality, placing it above average 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.

Hexavalent chromium (chromium-6) was detected at 4.60 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 →
90.5 out of 100 Grade A
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
43.5/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
15/20
B
No PFAS compounds detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is South Pasadena, CA water safe to drink?

Use Caution

South Pasadena's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (90.5/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 2 water systems serve approximately 25,389 residents using surface water (rivers, lakes, or reservoirs).

2
Active Violations
0.0 ppb
Lead (90th %ile)
None
PFAS Detected
10 events
Disaster History

Recent water quality updates for South Pasadena

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into South Pasadena's water quality assessment. Grade: A (90.5/100).

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, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-4683). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Arsenic.

Violation
2 drinking water violations recorded

1 health-based. Contaminants: Arsenic.

Violation
1 drinking water violation recorded

Contaminants: Arsenic.

Key contaminant findings

Based on the most recent EPA sampling data for South Pasadena's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

South Pasadena's water system has 14 total violations on record, including 5 health-based violations. 2 remain unresolved.

MCLMROther
Most recent violations:
Jan 2013 Arsenic Resolved
Oct 2008 Arsenic Resolved
Oct 2008 Arsenic Resolved
Apr 2008 Arsenic Resolved
Dec 1999 Coliform (TCR) Resolved

Flood & environmental risk

Los Angeles 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 San Gabriel R Ab Whittier Narrows Dam, Arroyo Seco Nr Pasadena, Rio Hondo Ab Whittier Narrows Dam, Rio Hondo Bl Whittier Narrows Dam.

SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-3592
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4683
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-3591

Where does South Pasadena's water come from?

South Pasadena's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 25,389 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include San Gabriel R Ab Whittier Narrows Dam (river), Arroyo Seco Nr Pasadena (river), Rio Hondo Ab Whittier Narrows Dam (river), Rio Hondo Bl Whittier Narrows Dam (river).

What South Pasadena 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.

Monitor alerts during storms

South Pasadena'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
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.4 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 0.4 µg/LHAA9: 0.5 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
4.60 µg/L
CA MCL (no federal MCL): 10 µg/L · 46% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
320.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 21% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
8.0 µg/L
EPA Secondary MCL: 50 µg/L · 16% of limit
DetectedUCMR 4 Data
Perchlorate
Inorganic
Elevated
4.50 µg/L
CA MCL (no federal MCL): 6 µg/L · 75% of limit
DetectedUCMR 1 Data (2001–2005)
Vanadium
Inorganic
Detected
8.40 µg/L
EPA Short-term HA: 21 µg/L · 40% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
110.0 µg/L
EPA Lifetime HA: 210 µg/L · 52% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
12.00 µg/L
EPA Lifetime HA: 40 µg/L · 30% of limit
DetectedUCMR 3 Data
PFAS Testing

Forever chemicals overview

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

Violation summary

14
Total violations
5
Health-based
2
Active / unresolved
Jan 2013
Most recent violation
Compliance Record

Violations & advisories

14 Total
2 Active
5 Health-based
12 Resolved
Violations by category
Arsenic Rule
4
Total Coliform Rule
2
Lead and Copper Rule
2
Miscellaneous Other Rules
2
Radionuclides and Revised Rad Rule
2
Jan 1996 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Jan 2013 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Mar 2013
Oct 2008 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Dec 2008
Oct 2008 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2008
Apr 2008 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2008
Dec 1999 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Dec 1999
May 1995 Resolved
Nitrate
Max Contaminant Level
Health-Based Health Resolved Jun 1995
Jul 1993 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2003
Jan 1993 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jan 1993
Aug 1984 Resolved
Miscellaneous Other Rules
Other Violation Resolved Aug 1984
Jul 1984 Resolved
Miscellaneous Other Rules
Other Violation Resolved Jul 1984
Oct 1981 Resolved
Gross Alpha, Excl. Radon and U
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 1982
Oct 1980 Resolved
Gross Alpha, Excl. Radon and U
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 1981
Industrial pollution

Top industrial polluters within 10 miles of South Pasadena

Industrial polluters nearby

Reported releases to surface water by facilities near South Pasadena, ranked by pounds discharged annually.

Total reported releases to surface water: 37 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
LOS ANGELES GALVANIZING CO.
Fabricated Metals · NA
HUNTINGTON PARK, CA90255
Zinc compounds178.8 mi
ATLAS GALVANIZING LLC
Fabricated Metals · NA
VERNON, CA90058
Zinc compounds98.5 mi
SOLVENTUM ORTHODONTICS CORP
Miscellaneous Manufacturing · SOLVENTUM US LLC
MONROVIA, CA91016
Chromium88.7 mi
GCP APPLIED TECHNOLOGIES INC
Chemicals · SAINT-GOBAIN CORP
LOS ANGELES, CA90040
Nitrate compounds (water dissociable; reportable only when in aqueous solution)29.4 mi
LOS ANGELES PUMP & VALVE
Primary Metals · NA
HUNTINGTON PARK, CA90255
Copper19.0 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of South Pasadena

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.

+ 3 more sites

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

10
Declared disasters
Mar 2023
Most recent
Flood
Most common type

Los Angeles 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, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4683
Jan 2023
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #3591
Mar 2017
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #4305
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3248
Feb 1993
SEVERE WINTER STORM, MUD & LAND SLIDES, & FLOODING
Flood FEMA #979

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.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 7.0 ppb from 1992 (7.0 ppb) to 2025 (0.0 ppb).
Contaminant Rankings

See how South Pasadena compares by contaminant

Explore where South Pasadena ranks among all California cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
25,389
Water Systems
2
Source breakdown
Purchased Surface Water
1
Groundwater
1
Water Source

Where South Pasadena's water comes from

Purchased Surface Water

South Pasadena'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 25,389 people through 2 water systems.

Local Hydrology

Water bodies near South Pasadena

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

San Gabriel R Ab Whittier Narrows Dam
river
Arroyo Seco Nr Pasadena
river
Rio Hondo Ab Whittier Narrows Dam
river
Rio Hondo Bl Whittier Narrows Dam
river
Infrastructure

Water systems serving South Pasadena

System Name PWSID Population Source
CITY OF SOUTH PASADENA CA1910154 25,329 SWP
ANTELOPE VALLEY MOBILE ESTATES CA1500485 60 GW
Regional Comparison

How South Pasadena compares

Full California rankings →

South Pasadena's score of 90.5/100 is above the average of 57/100 among major California cities. It outscores 9 of 10 nearby cities.

South Pasadena (this city)
90.5
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About South Pasadena, CA

Economic Profile
$127,882
Median Income
$1,426,339
Median Home Value
$2,135/mo
Median Rent
5.2%
Unemployment
Community
40.6
Median Age
3,011
People / sq mi
71.7%
College Educated
46.6%
Homeownership
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Frequently asked questions

Is South Pasadena, CA tap water safe to drink?

South Pasadena's water quality earned a grade of A (90.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #124 out of 694 cities tested in California.

What contaminants are in South Pasadena's water?

Lead was measured at 0.0 ppb (90th percentile). No PFAS compounds were detected. 14 violations are on record.

How is South Pasadena'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 South Pasadena?

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

Where does South Pasadena's water come from?

South Pasadena's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 25,389 residents.

What health violations has South Pasadena's water system had?

South Pasadena has 5 health-based violations on record. The most recent violation was recorded in January 2013. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.

How does South Pasadena's water compare to other cities?

South Pasadena ranks #124 out of 694 cities in California (better than 82% of state cities) and #2155 out of 15744 cities nationally (86th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.