WaterVerge

Is Corona, CA Tap Water Safe to Drink?

Graded D — but Copper, Manganese and 3 more were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

175K residents served 5 water systems PWSID: CA3310037
Overall Score
49.3 / 100
Violations
11 active
Last Updated
May 2026
Source
Purchased surface water
#610 of 694 in California Top 84% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
DGRADE
Water Quality Grade
49.3/100
waterverge.com
D 49.3/100

Corona, CA — Water Quality Report

Corona's drinking water received a grade of D (49.3 out of 100), indicating poor water quality. The city's 5 water systems serve approximately 174,518 residents using purchased surface water.

Lead levels were measured at 2.5 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 5 PFAS compounds in the water supply.

The system has 218 violations on record, including 81 health-based violations. 11 remain unresolved.

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

What to know about Corona's water

Corona ranks #610 out of 694 cities in California for water quality, placing it among the lowest-rated 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 0.43 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.

The system has seen 8 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
49.3 out of 100 Grade D
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
10.2/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 2.5 ppb (90th percentile).
Contaminants
11.1/20
D
5 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 Corona, CA water safe to drink?

Concerns Identified

Corona's drinking water has significant quality concerns based on EPA testing data. With a grade of D (49.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 174,518 residents using surface water (rivers, lakes, or reservoirs).

11
Active Violations
2.5 ppb
Lead (90th %ile)
5 compounds
PFAS Detected
10 events
Disaster History

Recent water quality updates for Corona

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

PFAS
5 PFAS "forever chemical" compounds 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 Corona's water quality assessment. Grade: D (49.3/100).

Violation
2 drinking water violations recorded

1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.

Disaster
TROPICAL STORM HILARY

Federal disaster declaration (FEMA DR-4750). Hurricane 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
2 drinking water violations recorded

Contaminants: TTHM, Total Haloacetic Acids (HAA5).

Key contaminant findings

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

Lead Within Limits
Detected: 2.5 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 1.77 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

PFAS (5 compounds) Elevated
Detected: Highest: lithium at 55.1000 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.

PFAS "forever chemicals" detected

UCMR 5 testing found 5 PFAS compounds in Corona's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.

Compound Level EPA MCL Status
lithium 55.1000 µg/L 0.004 µg/L Within Limit
PFBA 0.0076 µg/L 0.004 µg/L Within Limit
PFPeA 0.0061 µg/L 0.004 µg/L Within Limit
PFHxA 0.0038 µg/L 0.004 µg/L Within Limit

Violation history

Corona's water system has 218 total violations on record, including 81 health-based violations. 11 remain unresolved. 8 violations were issued in the last 5 years.

TTRPTMRMCLOther
Most recent violations:
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Apr 2022 TTHM Resolved
Apr 2022 Total Haloacetic Acids (HAA5) Resolved
Jan 2022 TTHM Resolved

Flood & environmental risk

Riverside 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 Santa Ana R A Mwd Crossing, Coldwater Canyon C Nr Corona, Temescal C A Corona Lk Nr Corona, Temescal C Ab Main St A Corona, Cucamonga C Nr Mira Loma.

TROPICAL STORM HILARY
Hurricane FEMA DR-4750
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-3591
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-4305

Where does Corona's water come from?

Corona's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 5 water systems serving approximately 174,518 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Santa Ana R A Mwd Crossing (river), Coldwater Canyon C Nr Corona (river), Temescal C A Corona Lk Nr Corona (river), Temescal C Ab Main St A Corona (river), Cucamonga C Nr Mira Loma (river).

What Corona residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Corona'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

Corona'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
2.5 ppb
EPA Action Level: 15 ppb · 17% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.77 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
lithium
PFAS / Forever Chemical
Near MCL
55.1000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
5.9 µg/L
EPA MCL: 60 µg/L · 10% of limit
Within LimitUCMR 4 DataHAA6Br: 6.1 µg/LHAA9: 10.2 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.43 µg/L
CA MCL (no federal MCL): 10 µg/L · 4% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Elevated
1100.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 73% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Detected
0.14 µg/L
EPA Health Advisory: 0.35 µg/L · 40% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Over SMCL
62.0 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
NDMA (N-Nitrosodimethylamine)
Disinfection Byproduct
Over CA PHG
15.0 ng/L
CA Public Health Goal: 10 ng/L · +20% over limit
Over CA PHGProbable CarcinogenUCMR 2 Data (2008–2010)
Perchlorate
Inorganic
Over CA MCL
13.00 µg/L
CA MCL (no federal MCL): 6 µg/L · +20% over limit
Over CA MCLUCMR 1 Data (2001–2005)
Vanadium
Inorganic
Detected
6.40 µg/L
EPA Short-term HA: 21 µg/L · 30% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
360.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Molybdenum
Inorganic
Detected
17.00 µg/L
EPA Lifetime HA: 40 µg/L · 43% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
55.1 µg/L
State screening level: 60 µg/L · 92% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
5
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

218
Total violations
81
Health-based
11
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

218 Total
11 Active
81 Health-based
207 Resolved
Violations by category
Nitrate Rule
72
Miscellaneous Other Rules
39
Synthetic Organic Chemicals
30
Volatile Organic Chemicals
22
Total Coliform Rule
15
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2012 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2007 Active
Consumer Confidence Rule
Other Violation 0
Jul 2006 Active
Consumer Confidence Rule
Other Violation 0
Jul 2005 Active
Consumer Confidence Rule
Other Violation 0
Jul 2005 Active
Consumer Confidence Rule
Other Violation 0
Jul 2004 Active
Consumer Confidence Rule
Other Violation 0
Oct 1997 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Apr 2022 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2022
Apr 2022 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2022
Jan 2022 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2022 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2021 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2021
Jan 2021 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2021
Jan 2018 Resolved
Nitrate
Max Contaminant Level
Health-Based Health Resolved Mar 2018
Jul 2017 Resolved
Nitrate
Max Contaminant Level
Health-Based Health Resolved Sep 2017
Apr 2017 Resolved
Nitrate
Max Contaminant Level
Health-Based Health Resolved Jun 2017
Showing 20 of 218 violations
Industrial pollution

Top industrial polluters within 10 miles of Corona

Industrial polluters nearby

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

Total reported releases to surface water: 12 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
US BATTERY MFG CO
Electrical Equipment · PALOS VERDES BUILDING CORP
CORONA, CA92879
Lead And Lead Compounds122.2 mi
3M CO - CORONA
Nonmetallic Mineral Product · 3M CO
CORONA, CA92881
3.2 mi
VULCAN MATERIALS CO CORONA
Petroleum · SMYRNA READY MIX LLC
CORONA, CA92879
2.5 mi
STREMICKS HERITAGE FOODS
Food · DAIRY FARMERS OF AMERICA INC
RIVERSIDE, CA92505
5.4 mi
AIRGAS SPECIALTY PRODUCTS-RIVERSIDE CA
Chemical Wholesalers · AIRGAS INC
RIVERSIDE, CA92504
9.4 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D1 — moderate drought

Riverside 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.

47.5%
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
Nov 2023
Most recent
Flood
Most common type

Riverside 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.

Nov 2023
TROPICAL STORM HILARY
Hurricane FEMA #4750
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 Corona's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
5 PFAS compounds detected
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 2.5 15 ppb Inorganic Safe
Copper (90th percentile) 1.77 1.3 mg/L Inorganic Over Limit
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 55.100 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 0.008 HI µg/L PFAS 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 0.004 HI µg/L PFAS Detected
PFHxS 0.003 HI µg/L PFAS 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 0.006 HI µg/L PFAS 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 3.5 ppb from 1992 (6.0 ppb) to 2025 (2.5 ppb).

Copper level (90th percentile)

Latest reading: 1.770 mg/L (1992)

EPA action level: 1.3 mg/L

Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
174,518
Water Systems
5
Source breakdown
Purchased Surface Water
3
Purchased Groundwater
1
Groundwater
1
Water Source

Where Corona's water comes from

Purchased Surface Water

Corona'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 174,518 people through 5 water systems.

Local Hydrology

Water bodies near Corona

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

Santa Ana R A Mwd Crossing
river
Coldwater Canyon C Nr Corona
river
Temescal C A Corona Lk Nr Corona
river
Temescal C Ab Main St A Corona
river
Cucamonga C Nr Mira Loma
river
Infrastructure

Water systems serving Corona

System Name PWSID Population Source
CORONA, CITY OF CA3310037 168,575 SWP
HOME GARDENS COUNTY WD CA3310018 3,095 SWP
CALIFORNIA INSTITUTION FOR WOMEN CA3610851 1,195 GWP
GLEN IVY HOT SPRINGS CA3301294 1,087 GW
GLEN EDEN SUN CLUB CA3301283 566 SWP
Regional Comparison

How Corona compares

Full California rankings →

Corona's score of 49.3/100 is below the average of 57/100 among major California cities. It outscores 5 of 10 nearby cities.

Corona (this city)
49.3
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About Corona, CA

Wikipedia →

Corona is a city in northwestern Riverside County, California, United States, directly bordering Orange and San Bernardino counties. Its current mayor is Jacque Casillas. At the 2020 census, the city had a population of 157,136, up from 152,374 at the 2010 census. Corona is surrounded by Riverside to the east, Norco to the north and northeast, Yorba Linda to the northwest, Cleveland National Forest and the Santa Ana Mountains to the west, southwest, and south. Several unincorporated communities are along the rest of the city's borders. Downtown Corona is approximately 48 miles (77 km) southeast of Downtown Los Angeles and 95 miles (153 km) north-northwest of San Diego.

Economic Profile
$103,727
Median Income
$622,273
Median Home Value
$2,020/mo
Median Rent
4.6%
Unemployment
Community
35.9
Median Age
1,533
People / sq mi
30.5%
College Educated
63.1%
Homeownership
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Frequently asked questions

Is Corona, CA tap water safe to drink?

Corona's water quality earned a grade of D (49.3/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #610 out of 694 cities tested in California.

What contaminants are in Corona's water?

Lead was measured at 2.5 ppb (90th percentile). 5 PFAS compounds were detected. 218 violations are on record.

How is Corona'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 Corona?

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

Where does Corona's water come from?

Corona's water is sourced from Purchased surface water. The city has 5 water systems serving approximately 174,518 residents.

What health violations has Corona's water system had?

Corona has 81 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 11 violations remain unresolved.

Why does Corona have so many PFAS compounds in its water?

5 different PFAS "forever chemical" compounds were detected in Corona's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. While detected, current levels are within EPA limits. An activated carbon filter can further reduce exposure.

How does Corona's water compare to other cities?

Corona ranks #610 out of 694 cities in California (better than 12% of state cities) and #13246 out of 15744 cities nationally (16th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.