WaterVerge

Is Cottonwood, Tselani, AZ Tap Water Safe to Drink?

Graded A, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

1K residents served 1 water system PWSID: NN0403021
Overall Score
92 / 100
Violations
3 active
Last Updated
May 2026
Source
Purchased ground water
#33 of 292 in Arizona Top 9% nationally
Native American
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
AGRADE
Water Quality Grade
92/100
waterverge.com
A 92/100

Cottonwood, Tselani, AZ — Water Quality Report

Cottonwood, Tselani's drinking water received a grade of A (92 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,334 residents using purchased ground water.

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 37 violations on record, including 4 health-based violations. 3 remain unresolved.

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

What to know about Cottonwood, Tselani's water

Cottonwood, Tselani ranks #33 out of 292 cities in Arizona for water quality, placing it above average in the state.

Cottonwood, Tselani purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.

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

Quality Breakdown

Water quality score

See methodology →
92 out of 100 Grade A
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
42/45
A
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: Purchased ground water.
Water Safety

Is Cottonwood, Tselani, AZ water safe to drink?

Concerns Identified

Cottonwood, Tselani's drinking water has significant quality concerns based on EPA testing data. With a grade of A (92/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,334 residents using groundwater (wells).

3
Active Violations
1.0 ppb
Lead (90th %ile)
6 events
Disaster History

Recent water quality updates for Cottonwood, Tselani

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Cottonwood, Tselani's water quality assessment. Grade: A (92/100).

Disaster
SEVERE STORMS AND FLOODING

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

Violation
2 drinking water violations recorded

Contaminants: Total Haloacetic Acids (HAA5), TTHM.

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Violation
1 drinking water violation recorded

Contaminants: Stage 2 Disinfectants and Disinfection Byproducts Rule.

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 Cottonwood, Tselani's water supply.

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

Well within EPA limits.

Violation history

Cottonwood, Tselani's water system has 37 total violations on record, including 4 health-based violations. 3 remain unresolved.

MROtherMCL
Most recent violations:
Jan 2020 Total Haloacetic Acids (HAA5) Resolved
Jan 2020 TTHM Resolved
Apr 2016 Revised Total Coliform Rule Open
Oct 2013 Stage 2 Disinfectants and Disinfection Byproducts Rule Open
Jul 2013 Arsenic Resolved

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 Cottonwood, Tselani's water come from?

Cottonwood, Tselani's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,334 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What Cottonwood, Tselani residents can do

Install a water filter

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

Cottonwood, Tselani'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

37
Total violations
4
Health-based
3
Active / unresolved
Jan 2020
Most recent violation
Compliance Record

Violations & advisories

37 Total
3 Active
4 Health-based
34 Resolved
Violations by category
Volatile Organic Chemicals
21
Total Coliform Rule
5
Stage 2 Disinfectants and Disinfection Byproducts Rule
3
Radionuclides and Revised Rad Rule
3
Arsenic Rule
2
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
Active
Compliance Violation
Monitoring 0
Jan 2020 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2020 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jul 2013 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Sep 2013
Apr 2013 Resolved
Arsenic
Max Contaminant Level
Health-Based Health Resolved Jun 2013
Dec 2012 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2012
Nov 2012 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 2012
Jul 2011 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jul 2011
Oct 2010 Resolved
Gross Alpha, Excl. Radon and U
Max Contaminant Level
Health-Based Health Resolved Dec 2010
Jan 2010 Resolved
Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
1,2,4-Trichlorobenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
Xylenes, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
o-Dichlorobenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
p-Dichlorobenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
1,1-Dichloroethylene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
Trichloroethylene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
1,1,2-Trichloroethane
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Jan 2005 Resolved
CHLOROBENZENE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2010
Showing 20 of 37 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 1.0 ppb from 1993 (2.0 ppb) to 2025 (1.0 ppb).
Contaminant Rankings

See how Cottonwood, Tselani compares by contaminant

Explore where Cottonwood, Tselani ranks among all Arizona cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Purchased Groundwater
Operator
Native American
Population Served
1,334
Water Systems
1
Water Source

Where Cottonwood, Tselani's water comes from

Purchased Groundwater

Cottonwood, Tselani purchases its water supply from a regional wholesale provider rather than treating raw water directly.

Water quality depends on both the wholesaler's treatment standards and the condition of Cottonwood, Tselani's local distribution pipes and storage facilities.

Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.

The system is operated by native american ownership and serves approximately 1,334 people through 1 water system.

Infrastructure

Water systems serving Cottonwood, Tselani

System Name PWSID Population Source
Cottonwood-Tselani NTUA NN0403021 1,334 GWP
Regional Comparison

How Cottonwood, Tselani compares

Full Arizona rankings →

Cottonwood, Tselani's score of 92/100 is above the average of 42/100 among major Arizona cities. It outscores 10 of 10 nearby cities.

Cottonwood, Tselani (this city)
92
Phoenix
37.5
Tucson
38.1
Mesa
40.6
Chandler
40.5
Gilbert
34.8
Arizona avg
42
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Cottonwood, Tselani, AZ tap water safe to drink?

Cottonwood, Tselani's water quality earned a grade of A (92/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #33 out of 292 cities tested in Arizona.

What contaminants are in Cottonwood, Tselani's water?

Lead was measured at 1.0 ppb (90th percentile). 37 violations are on record.

How is Cottonwood, Tselani'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 Cottonwood, Tselani?

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

Where does Cottonwood, Tselani's water come from?

Cottonwood, Tselani's water is sourced from Purchased ground water. The city has 1 water system serving approximately 1,334 residents.

What health violations has Cottonwood, Tselani's water system had?

Cottonwood, Tselani has 4 health-based violations on record. The most recent violation was recorded in January 2020. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

Is Cottonwood, Tselani's groundwater at risk of contamination?

Cottonwood, Tselani 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 37 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 Cottonwood, Tselani's water compare to other cities?

Cottonwood, Tselani ranks #33 out of 292 cities in Arizona (better than 89% of state cities) and #1418 out of 15744 cities nationally (91th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Cottonwood, Tselani's small water system affect quality?

Cottonwood, Tselani's system serves approximately 1,334 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 37 violations on record.