WaterVerge

Is Chilchinbeto, AZ Tap Water Safe to Drink?

Graded B+, with 14 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

1K residents served 2 water systems PWSID: NN0400290
Overall Score
83.2 / 100
Violations
14 active
Last Updated
May 2026
Source
Groundwater
#101 of 292 in Arizona Top 42% nationally
Native American
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
83.2/100
waterverge.com
B+ 83.2/100

Chilchinbeto, AZ — Water Quality Report

Chilchinbeto's drinking water received a grade of B+ (83.2 out of 100), indicating good water quality. The city's 2 water systems serve approximately 1,414 residents using groundwater.

Lead levels were measured at 1.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 105 violations on record, including 0 health-based violations. 14 remain unresolved.

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

What to know about Chilchinbeto's water

Chilchinbeto ranks #101 out of 292 cities in Arizona for water quality, placing it mid-range in the state.

Chilchinbeto 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.

As a small community water system, Chilchinbeto may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
83.2 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
33.2/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 1.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Chilchinbeto, AZ water safe to drink?

Concerns Identified

Chilchinbeto's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,414 residents using groundwater (wells).

14
Active Violations
1.0 ppb
Lead (90th %ile)
6 events
Disaster History

Recent water quality updates for Chilchinbeto

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Chilchinbeto's water quality assessment. Grade: B+ (83.2/100).

Violation
3 drinking water violations recorded

Contaminants: Nitrate, Nitrite, Revised Total Coliform Rule.

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Disaster
SEVERE STORMS AND FLOODING

Federal disaster declaration (FEMA DR-4620). Flood event — may have impacted local water infrastructure.

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 Chilchinbeto's water supply.

Lead Within Limits
Detected: 1.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Chilchinbeto's water system has 105 total violations on record, including 0 health-based violations. 14 remain unresolved. 5 violations were issued in the last 5 years.

MRRPTMONOther
Most recent violations:
Jan 2024 Nitrate Resolved
Jan 2024 Nitrite Resolved
Jan 2024 Revised Total Coliform Rule Open
Oct 2023 Revised Total Coliform Rule Open
Oct 2022 Revised Total Coliform Rule Open

Flood & environmental risk

Apache County has experienced 6 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.

SEVERE STORMS AND FLOODING
Flood FEMA DR-4620
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3241
SEVERE STORMS, TORNADOES & FLOODING
Flood FEMA DR-977

Where does Chilchinbeto's water come from?

Chilchinbeto's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,414 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Chilchinbeto residents can do

Install a water filter

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

Chilchinbeto'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
1.0 ppb
EPA Action Level: 15 ppb · 7% of limit
Safe Level
Compliance Record

Violation summary

105
Total violations
0
Health-based
14
Active / unresolved
Jan 2024
Most recent violation
Compliance Record

Violations & advisories

105 Total
14 Active
0 Health-based
91 Resolved
Violations by category
Volatile Organic Chemicals
42
Synthetic Organic Chemicals
34
Revised Total Coliform Rule
7
Total Coliform Rule
6
Nitrate Rule
4
Jan 2024 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Oct 2023 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Oct 2022 Active
Revised Total Coliform Rule
Reporting
Reporting 0
May 2020 Active
Revised Total Coliform Rule
Reporting
Reporting 0
Apr 2016 Active
Revised Total Coliform Rule
Other Violation 0
Apr 2016 Active
Revised Total Coliform Rule
Other Violation 0
Oct 2013 Active
Stage 2 Disinfectants and Disinfection Byproducts Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2013 Active
Stage 2 Disinfectants and Disinfection Byproducts Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2008 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2006 Active
Consumer Confidence Rule
Other Violation 0
Jul 2005 Active
Consumer Confidence Rule
Other Violation 0
Jan 2004 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jan 2024 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2017 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2017
Jan 2017 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2017
Jul 2016 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Jul 2016
Dec 2012 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2012
Showing 20 of 105 violations
Environmental Risk

Flood & disaster history

6
Declared disasters
Sep 2021
Most recent
Flood
Most common type

Apache County has experienced 6 federally declared disasters since 1970. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2021
SEVERE STORMS AND FLOODING
Flood FEMA #4620
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
Mar 1978
SEVERE STORMS & FLOODING
Flood FEMA #551
Sep 1970
HEAVY RAINS & FLASH
Flood FEMA #294

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.0 15 ppb Inorganic Safe
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 1993 (4.0 ppb) to 2025 (0.5 ppb).
Contaminant Rankings

See how Chilchinbeto compares by contaminant

Explore where Chilchinbeto ranks among all Arizona cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Native American
Population Served
1,414
Water Systems
2
Water Source

Where Chilchinbeto's water comes from

Groundwater

Chilchinbeto'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 native american ownership and serves approximately 1,414 people through 2 water systems.

Infrastructure

Water systems serving Chilchinbeto

System Name PWSID Population Source
Chilchinbeto NTUA NN0400290 1,276 GW
Chilchinbeto Community Day School BIA NN0433002 138 GW
Regional Comparison

How Chilchinbeto compares

Full Arizona rankings →

Chilchinbeto's score of 83.2/100 is above the average of 42/100 among major Arizona cities. It outscores 10 of 10 nearby cities.

Chilchinbeto (this city)
83.2
Phoenix
37.5
Tucson
38.1
Mesa
40.6
Chandler
40.5
Gilbert
34.8
Arizona avg
42
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Frequently asked questions

Is Chilchinbeto, AZ tap water safe to drink?

Chilchinbeto's water quality earned a grade of B+ (83.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #101 out of 292 cities tested in Arizona.

What contaminants are in Chilchinbeto's water?

Lead was measured at 1.0 ppb (90th percentile). 105 violations are on record.

How is Chilchinbeto'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 Chilchinbeto?

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

Where does Chilchinbeto's water come from?

Chilchinbeto's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,414 residents.

Is Chilchinbeto's groundwater at risk of contamination?

Chilchinbeto 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 105 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 Chilchinbeto's water compare to other cities?

Chilchinbeto ranks #101 out of 292 cities in Arizona (better than 65% of state cities) and #6556 out of 15744 cities nationally (58th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.