WaterVerge

Is Hanford, CA Tap Water Safe to Drink?

Graded D+, with 10 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

66K residents served 5 water systems PWSID: CA1610003
Overall Score
50.6 / 100
Violations
10 active
Last Updated
May 2026
Source
Groundwater
#605 of 694 in California Top 83% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
D+GRADE
Water Quality Grade
50.6/100
waterverge.com
D+ 50.6/100

Hanford, CA — Water Quality Report

Hanford's drinking water received a grade of D+ (50.6 out of 100), indicating poor water quality. The city's 5 water systems serve approximately 65,603 residents using groundwater.

Lead levels were measured at 0.7 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 236 violations on record, including 197 health-based violations. 10 remain unresolved.

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

What to know about Hanford's water

Hanford ranks #605 out of 694 cities in California for water quality, placing it among the lowest-rated in the state.

Hanford relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

The system has seen 11 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
50.6 out of 100 Grade D+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
0/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.7 ppb (90th percentile).
Contaminants
15.6/20
B
No PFAS compounds detected.
Compliance
10/10
A
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Hanford, CA water safe to drink?

Concerns Identified

Hanford's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (50.6/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 65,603 residents using groundwater (wells).

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

Recent water quality updates for Hanford

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Hanford's water quality assessment. Grade: D+ (50.6/100).

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Violation
2 drinking water violations recorded

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

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

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.

Key contaminant findings

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

Lead Within Limits
Detected: 0.7 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Hanford's water system has 236 total violations on record, including 197 health-based violations. 10 remain unresolved. 11 violations were issued in the last 5 years.

MRTTRPTMCLOther
Most recent violations:
Oct 2025 Lead and Copper Rule Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2023 Lead and Copper Rule Open
Jan 2022 Nitrate Resolved

Flood & environmental risk

Kings County has experienced 9 federally declared disasters since 1969. 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 Cross C A Kansas Ave Nr Hanford.

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-4308

Where does Hanford's water come from?

Hanford's drinking water comes from groundwater (wells), supplied by 5 water systems serving approximately 65,603 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Cross C A Kansas Ave Nr Hanford (river).

What Hanford residents can do

Install a water filter

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

Hanford'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
0.7 ppb
EPA Action Level: 15 ppb · 5% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
7.2 µg/L
EPA MCL: 60 µg/L · 12% of limit
Within LimitUCMR 4 DataHAA6Br: 17.0 µg/LHAA9: 18.0 µg/L
Strontium
Inorganic
Detected
92.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 6% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
30.0 µg/L
EPA Secondary MCL: 50 µg/L · 60% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
1.10 µg/L
EPA Short-term HA: 21 µg/L · 5% 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

236
Total violations
197
Health-based
10
Active / unresolved
Oct 2025
Most recent violation
Compliance Record

Violations & advisories

236 Total
10 Active
197 Health-based
226 Resolved
6 SNC
Violations by category
Arsenic Rule
150
Total Coliform Rule
41
Radionuclides and Revised Rad Rule
17
Stage 2 Disinfectants and Disinfection Byproducts Rule
10
Lead and Copper Rule
9
Oct 2025 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
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 2023 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2017 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2013 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2009 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2005 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Jan 2022 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Apr 2021 Resolved
TTHM
Max Contaminant Level
SNC Health Resolved Jun 2021
Jan 2021 Resolved
TTHM
Max Contaminant Level
SNC Health Resolved Mar 2021
Jan 2021 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2021
Jan 2021 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2021
Jan 2021 Resolved
TTHM
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2021
Oct 2020 Resolved
TTHM
Max Contaminant Level
SNC Health Resolved Dec 2020
Jul 2020 Resolved
TTHM
Max Contaminant Level
SNC Health Resolved Sep 2020
Jan 2020 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2020 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Showing 20 of 236 violations
Industrial pollution

Top industrial polluters within 10 miles of Hanford

Industrial polluters nearby

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

FacilityTop chemicalTo surface water (lbs/yr)Distance
LEPRINO FOODS CO
Food · LEPRINO FOODS CO
LEMOORE, CA93245
7.6 mi
MARQUEZ BROTHERS INTERNATIONAL, INC- DAIRY & WHEY PLANT
Food · MARQUEZ BROTHERS INTERNATIONAL INC
HANFORD, CA932305043
0.3 mi
AIRGAS SPECIALTY PRODUCTS - HANFORD CA
Chemical Wholesalers · AIRGAS INC
HANFORD, CA93230
3.4 mi
TESSENDERLO KERLEY INC HANFORD PLANT
Chemicals · TESSENDERLO KERLEY INC
HANFORD, CA93230
3.9 mi
CEMEX LEMOORE PLANT
Nonmetallic Mineral Product · CEMEX INC
LEMOORE, CA93245
8.6 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

9
Declared disasters
Mar 2023
Most recent
Flood
Most common type

Kings County has experienced 9 federally declared disasters since 1969. 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
Apr 2017
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #4308
Jan 2011
SEVERE WINTER STORMS, FLOODING, AND DEBRIS AND MUD FLOWS
Flood FEMA #1952
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3248
Feb 1983
COASTAL STORMS, FLOODS, SLIDES & TORNADOES
Coastal Storm FEMA #677

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.7 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 1.3 ppb from 1992 (2.0 ppb) to 2025 (0.7 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
65,603
Water Systems
5
Water Source

Where Hanford's water comes from

Groundwater

Hanford's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 65,603 people through 5 water systems.

Local Hydrology

Water bodies near Hanford

Hanford is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Cross C A Kansas Ave Nr Hanford
river
Infrastructure

Water systems serving Hanford

System Name PWSID Population Source
HANFORD, CITY OF CA1610003 62,127 GW
HOME GARDEN CSD CA1610007 1,750 GW
STRATFORD PUD CA1610006 1,277 GW
WESTERN ACRES MUTUAL WATER COMPANY CA1503475 380 GW
HARDWICK WATER COMPANY CA1600507 69 GW
Regional Comparison

How Hanford compares

Full California rankings →

Hanford's score of 50.6/100 is below the average of 57/100 among major California cities. It outscores 5 of 10 nearby cities.

Hanford (this city)
50.6
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
City Profile

About Hanford, CA

Wikipedia →

Hanford is the most populous city in and the county seat of Kings County, California, located in the San Joaquin Valley region of the greater Central Valley. The population was 57,990 at the 2020 census.

Economic Profile
$73,819
Median Income
$291,152
Median Home Value
$1,194/mo
Median Rent
8.2%
Unemployment
Community
32.7
Median Age
1,280
People / sq mi
19%
College Educated
61.9%
Homeownership
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Frequently asked questions

Is Hanford, CA tap water safe to drink?

Hanford's water quality earned a grade of D+ (50.6/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #605 out of 694 cities tested in California.

What contaminants are in Hanford's water?

Lead was measured at 0.7 ppb (90th percentile). No PFAS compounds were detected. 236 violations are on record.

How is Hanford'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 Hanford?

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

Where does Hanford's water come from?

Hanford's water is sourced from Groundwater. The city has 5 water systems serving approximately 65,603 residents.

What health violations has Hanford's water system had?

Hanford has 197 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.

Is Hanford's groundwater at risk of contamination?

Hanford uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 236 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Hanford's water compare to other cities?

Hanford ranks #605 out of 694 cities in California (better than 13% of state cities) and #12979 out of 15744 cities nationally (18th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.