WaterVerge

Is Chino, CA Tap Water Safe to Drink?

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

97K residents served 2 water systems PWSID: CA3610012
Overall Score
76.1 / 100
Violations
14 active
Last Updated
May 2026
Source
Purchased surface water
#447 of 694 in California Top 60% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
76.1/100
waterverge.com
B 76.1/100

Chino, CA — Water Quality Report

Chino's drinking water received a grade of B (76.1 out of 100), indicating good water quality. The city's 2 water systems serve approximately 97,102 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 26 violations on record, including 9 health-based violations. 14 remain unresolved.

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

What to know about Chino's water

Chino ranks #447 out of 694 cities in California for water quality, placing it below 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 6.20 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 →
76.1 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
31.5/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17.6/20
B
No PFAS compounds detected.
Compliance
3/10
F
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Chino, CA water safe to drink?

Concerns Identified

Chino's drinking water has significant quality concerns based on EPA testing data. With a grade of B (76.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 97,102 residents using surface water (rivers, lakes, or reservoirs).

14
Active Violations
0.0 ppb
Lead (90th %ile)
None
PFAS Detected
10 events
Disaster History

Recent water quality updates for Chino

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Chino's water quality assessment. Grade: B (76.1/100).

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
4 drinking water violations recorded

4 health-based. Contaminants: Groundwater Rule.

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Key contaminant findings

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

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

Well within EPA limits.

Chromium-6 (Hexavalent Chromium) Elevated
Detected: 6.20 µg/L Limit: 10 µg/L (California MCL — no federal limit)

The "Erin Brockovich" chemical. There is no federal MCL, but California has set a limit of 10 µg/L. Reverse osmosis filtration is effective at removing hexavalent chromium.

Violation history

Chino's water system has 26 total violations on record, including 9 health-based violations. 14 remain unresolved. 5 violations were issued in the last 5 years.

TTMROtherMCL
Most recent violations:
Jun 2022 Groundwater Rule Open
Jun 2022 Groundwater Rule Open
Jun 2022 Groundwater Rule Open
Jun 2022 Groundwater Rule Open
Oct 2021 Lead and Copper Rule Open

Flood & environmental risk

San Bernardino 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 Temescal C Ab Main St A Corona, San Antonio C A Riverside Drive Nr Chino, Chino C A Schaefer Avenue Nr Chino, Cucamonga C Nr Mira Loma, Santa Ana R Bl Prado Dam.

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 DEBRIS AND MUD FLOWS
Flood FEMA DR-1952

Where does Chino's water come from?

Chino's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 97,102 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Temescal C Ab Main St A Corona (river), San Antonio C A Riverside Drive Nr Chino (river), Chino C A Schaefer Avenue Nr Chino (river), Cucamonga C Nr Mira Loma (river), Santa Ana R Bl Prado Dam (river).

What Chino residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Chino's water.

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

Chino'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
7.7 µg/L
EPA MCL: 60 µg/L · 13% of limit
Within LimitUCMR 4 DataHAA6Br: 10.1 µg/LHAA9: 15.9 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Elevated
6.20 µg/L
CA MCL (no federal MCL): 10 µg/L · 62% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
450.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 30% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
1.8 µg/L
EPA Secondary MCL: 50 µg/L · 4% of limit
DetectedUCMR 4 Data
NDMA (N-Nitrosodimethylamine)
Disinfection Byproduct
Detected
2.5 ng/L
CA Public Health Goal: 10 ng/L · 25% of limit
DetectedProbable CarcinogenUCMR 2 Data (2008–2010)
Perchlorate
Inorganic
Over CA MCL
21.00 µg/L
CA MCL (no federal MCL): 6 µg/L · +20% over limit
Over CA MCLUCMR 1 Data (2001–2005)
Vanadium
Inorganic
Detected
8.30 µg/L
EPA Short-term HA: 21 µg/L · 40% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
380.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Molybdenum
Inorganic
Detected
6.70 µg/L
EPA Lifetime HA: 40 µg/L · 17% 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

26
Total violations
9
Health-based
14
Active / unresolved
Jun 2022
Most recent violation
Compliance Record

Violations & advisories

26 Total
14 Active
9 Health-based
12 Resolved
Violations by category
Total Coliform Rule
7
Ground Water Rule
6
Lead and Copper Rule
5
Stage 2 Disinfectants and Disinfection Byproducts Rule
4
Consumer Confidence Rule
1
Jun 2022 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Jun 2022 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Jun 2022 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Jun 2022 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Oct 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2019 Active
Consumer Confidence Rule
Other Violation 0
Jul 2014 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2014 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2014 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2006 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2005 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2003 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
May 2018 Resolved
Nitrate
Max Contaminant Level
Health-Based Health Resolved May 2018
Jan 2016 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2016
Jan 2016 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2016
Jan 2015 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Jan 2015 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Aug 2013 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Aug 2013
Showing 20 of 26 violations
Industrial pollution

Top industrial polluters within 10 miles of Chino

Industrial polluters nearby

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

Total reported releases to surface water: 19 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
US BATTERY MFG CO
Electrical Equipment · PALOS VERDES BUILDING CORP
CORONA, CA92879
Lead And Lead Compounds129.9 mi
TST INC. DBA TIMCO DBA TANDE M INDUSTRIES
Primary Metals · TST INC
FONTANA, CA92337
Copper38.9 mi
SIERRA ALUMINUM CO PLANT II
Primary Metals · SIERRA ALUMINUM CO
FONTANA, CA92337
Lead29.0 mi
PACIFIC FORGE INC.
Fabricated Metals · AVIS INDUSTRIAL CORP
FONTANA, CA92337
Chromium19.5 mi
ARLON EMD
Computers and Electronic Products · NA
RANCHO CUCAMONGA, CA91730
Copper19.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D1 — moderate drought

San Bernardino County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

50.7%
Months in D2+ (last 30y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

10
Declared disasters
Mar 2023
Most recent
Flood
Most common type

San Bernardino 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
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
Feb 1992
RAIN/SNOW/WIND STORMS, FLOODING, MUDSLIDES
Flood FEMA #935

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 16.0 ppb from 1992 (16.0 ppb) to 2027 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
97,102
Water Systems
2
Source breakdown
Purchased Surface Water
1
Groundwater
1
Water Source

Where Chino's water comes from

Purchased Surface Water

Chino'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 97,102 people through 2 water systems.

Local Hydrology

Water bodies near Chino

Chino is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Temescal C Ab Main St A Corona
river
San Antonio C A Riverside Drive Nr Chino
river
Chino C A Schaefer Avenue Nr Chino
river
Cucamonga C Nr Mira Loma
river
Santa Ana R Bl Prado Dam
river
Infrastructure

Water systems serving Chino

System Name PWSID Population Source
CHINO, CITY OF CA3610012 86,435 SWP
CALIFORNIA INSTITUTION FOR MEN CA3610850 10,667 GW
Regional Comparison

How Chino compares

Full California rankings →

Chino's score of 76.1/100 is above the average of 57/100 among major California cities. It outscores 7 of 10 nearby cities.

Chino (this city)
76.1
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About Chino, CA

Economic Profile
$99,385
Median Income
$596,803
Median Home Value
$2,001/mo
Median Rent
5.5%
Unemployment
Community
36.9
Median Age
1,188
People / sq mi
28.1%
College Educated
63.7%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Chino, CA tap water safe to drink?

Chino's water quality earned a grade of B (76.1/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #447 out of 694 cities tested in California.

What contaminants are in Chino's water?

Lead was measured at 0.0 ppb (90th percentile). No PFAS compounds were detected. 26 violations are on record.

How is Chino'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 Chino?

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

Where does Chino's water come from?

Chino's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 97,102 residents.

What health violations has Chino's water system had?

Chino has 9 health-based violations on record. The most recent violation was recorded in June 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 14 violations remain unresolved.

How does Chino's water compare to other cities?

Chino ranks #447 out of 694 cities in California (better than 36% of state cities) and #9382 out of 15744 cities nationally (40th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.