WaterVerge

Is Willcox, AZ Tap Water Safe to Drink?

Graded D, with 33 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

4K residents served 2 water systems PWSID: AZ0402035
Overall Score
47.2 / 100
Violations
33 active
Last Updated
May 2026
Source
Groundwater
#209 of 292 in Arizona Top 87% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
DGRADE
Water Quality Grade
47.2/100
waterverge.com
D 47.2/100

Willcox, AZ — Water Quality Report

Willcox's drinking water received a grade of D (47.2 out of 100), indicating poor water quality. The city's 2 water systems serve approximately 3,638 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 235 violations on record, including 7 health-based violations. 33 remain unresolved.

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

What to know about Willcox's water

Willcox ranks #209 out of 292 cities in Arizona for water quality, placing it below average in the state.

Willcox 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.

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.

The system has seen 24 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
47.2 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 0.0 ppb (90th percentile).
Contaminants
14.2/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Willcox, AZ water safe to drink?

Concerns Identified

Willcox's drinking water has significant quality concerns based on EPA testing data. With a grade of D (47.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 3,638 residents using groundwater (wells).

33
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
4 events
Disaster History

Recent water quality updates for Willcox

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 Willcox's water quality assessment. Grade: D (47.2/100).

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Revised Total Coliform Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
2 drinking water violations recorded

Contaminants: Lead and Copper Rule, Chlorine.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3241). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

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

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

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 34.7000 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

Willcox's water system has 235 total violations on record, including 7 health-based violations. 33 remain unresolved. 24 violations were issued in the last 5 years.

TTOtherMRRPTMONMCL
Most recent violations:
Sep 2025 Revised Total Coliform Rule Open
Jul 2025 Consumer Confidence Rule Open
Oct 2023 Lead and Copper Rule Open
Oct 2023 Chlorine Resolved
Sep 2023 Revised Total Coliform Rule Open

Flood & environmental risk

Cochise County has experienced 4 federally declared disasters since 1970. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3241
SEVERE STORMS, TORNADOES & FLOODING
Flood FEMA DR-977
SEVERE STORMS & FLOODING
Flood FEMA DR-691

Where does Willcox's water come from?

Willcox's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 3,638 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Willcox residents can do

Install a water filter

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

Willcox'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
lithium
PFAS / Forever Chemical
Near MCL
34.7000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
Lithium
Inorganic
Detected
34.7 µg/L
State screening level: 60 µg/L · 58% of 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

235
Total violations
7
Health-based
33
Active / unresolved
Sep 2025
Most recent violation
Compliance Record

Violations & advisories

235 Total
33 Active
7 Health-based
202 Resolved
4 SNC
Violations by category
Volatile Organic Chemicals
60
Stage 1 Disinfectants and Disinfection Byproducts Rule
40
Total Coliform Rule
39
Synthetic Organic Chemicals
24
Inorganic Chemicals
18
Sep 2025 Active
Revised Total Coliform Rule
Treatment Technique
Health-Based Health 0
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Oct 2023 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Sep 2023 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Aug 2023 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Aug 2023 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Apr 2023 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Jan 2023 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2022 Active
Revised Total Coliform Rule
Treatment Technique
Health-Based Health 0
Oct 2022 Active
Consumer Confidence Rule
Other Violation 0
Jul 2022 Active
Consumer Confidence Rule
Other Violation 0
Apr 2022 Active
Public Notice
Other Violation 0
Oct 2021 Active
Consumer Confidence Rule
Other Violation 0
Jul 2021 Active
Consumer Confidence Rule
Other Violation 0
Mar 2021 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Feb 2020 Active
Public Notice
Other Violation 0
Jan 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Nov 2019 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2019 Active
Consumer Confidence Rule
Other Violation 0
Oct 2019 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Showing 20 of 235 violations
Environmental Risk

Drought conditions

D1 — moderate drought

Cochise 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.

40.4%
Months in D2+ (last 30y)

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

Environmental Risk

Flood & disaster history

4
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Cochise County has experienced 4 federally declared disasters since 1970. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3241
Jan 1993
SEVERE STORMS, TORNADOES & FLOODING
Flood FEMA #977
Oct 1983
SEVERE STORMS & FLOODING
Flood FEMA #691
Sep 1970
HEAVY RAINS & FLASH
Flood FEMA #294

Recommended water filters

Based on contaminants detected in Willcox'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) 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 34.700 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 decreased by 4.0 ppb from 1992 (4.0 ppb) to 2025 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
3,638
Water Systems
2
Water Source

Where Willcox's water comes from

Groundwater

Willcox'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 3,638 people through 2 water systems.

Infrastructure

Water systems serving Willcox

System Name PWSID Population Source
CITY OF WILLCOX AZ0402035 3,236 GW
CS WINCHESTER WATER COMPANY AZ0402110 402 GW
Regional Comparison

How Willcox compares

Full Arizona rankings →

Willcox's score of 47.2/100 is above the average of 42/100 among major Arizona cities. It outscores 9 of 10 nearby cities.

Willcox (this city)
47.2
Phoenix
37.5
Tucson
38.1
Mesa
40.6
Chandler
40.5
Gilbert
34.8
Arizona avg
42
City Profile

About Willcox, AZ

Economic Profile
$40,884
Median Income
$110,903
Median Home Value
$856/mo
Median Rent
16.8%
Unemployment
Community
30.8
Median Age
203
People / sq mi
9.1%
College Educated
47.2%
Homeownership
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Frequently asked questions

Is Willcox, AZ tap water safe to drink?

Willcox's water quality earned a grade of D (47.2/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #209 out of 292 cities tested in Arizona.

What contaminants are in Willcox's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 235 violations are on record.

How is Willcox'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 Willcox?

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

Where does Willcox's water come from?

Willcox's water is sourced from Groundwater. The city has 2 water systems serving approximately 3,638 residents.

What health violations has Willcox's water system had?

Willcox has 7 health-based violations on record. The most recent violation was recorded in September 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 33 violations remain unresolved.

Is Willcox's groundwater at risk of contamination?

Willcox 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 235 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 Willcox's water compare to other cities?

Willcox ranks #209 out of 292 cities in Arizona (better than 28% of state cities) and #13653 out of 15744 cities nationally (13th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.