WaterVerge

Is San Xavier West, AZ Tap Water Safe to Drink?

Graded A-, with 1 unresolved violation on record. See what was cited — and what it means for your tap. What to do next ↓

2K residents served 1 water system PWSID: 090400035
Overall Score
87.9 / 100
Violations
1 active
Last Updated
May 2026
Source
Groundwater
#74 of 292 in Arizona Top 24% nationally
Native American
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
87.9/100
waterverge.com
A- 87.9/100

San Xavier West, AZ — Water Quality Report

San Xavier West's drinking water received a grade of A- (87.9 out of 100), indicating good water quality. The city's 1 water system serves approximately 1,511 residents using groundwater.

Lead levels were measured at 0.9 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 46 violations on record, including 3 health-based violations. 1 remains unresolved.

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

What to know about San Xavier West's water

San Xavier West ranks #74 out of 292 cities in Arizona for water quality, placing it mid-range in the state.

San Xavier West 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, San Xavier West may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
87.9 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
35.9/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.9 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
10/10
A
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is San Xavier West, AZ water safe to drink?

Use Caution

San Xavier West's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (87.9/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 1,511 residents using groundwater (wells).

1
Active Violations
0.9 ppb
Lead (90th %ile)
9 events
Disaster History

Recent water quality updates for San Xavier West

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into San Xavier West's water quality assessment. Grade: A- (87.9/100).

Violation
1 drinking water violation recorded

Contaminants: Arsenic.

Violation
1 drinking water violation recorded

Contaminants: Arsenic.

Violation
1 drinking water violation recorded

Contaminants: Arsenic.

Disaster
HURRICANE KATRINA EVACUATION

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

Disaster
SEVERE STORMS, TORNADOES & FLOODING

Federal disaster declaration (FEMA DR-977). Flood event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for San Xavier West's water supply.

Lead Within Limits
Detected: 0.9 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

San Xavier West's water system has 46 total violations on record, including 3 health-based violations. 1 remain unresolved. 6 violations were issued in the last 5 years.

MRMCL
Most recent violations:
Nov 2025 Arsenic Resolved
Oct 2025 Arsenic Resolved
Aug 2025 Arsenic Resolved
Nov 2024 Arsenic Resolved
Jan 2023 Total Haloacetic Acids (HAA5) Resolved

Flood & environmental risk

Pima County has experienced 9 federally declared disasters since 1966. 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-884

Where does San Xavier West's water come from?

San Xavier West's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,511 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.

What San Xavier West residents can do

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

San Xavier West'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
0.9 ppb
EPA Action Level: 15 ppb · 6% of limit
Safe Level
Compliance Record

Violation summary

46
Total violations
3
Health-based
1
Active / unresolved
Nov 2025
Most recent violation
Compliance Record

Violations & advisories

46 Total
1 Active
3 Health-based
45 Resolved
2 SNC
Violations by category
Synthetic Organic Chemicals
30
Arsenic Rule
4
Nitrate Rule
3
Total Coliform Rule
3
Stage 2 Disinfectants and Disinfection Byproducts Rule
2
Active
Compliance Violation
Monitoring 0
Nov 2025 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 2025
Oct 2025 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 2025
Aug 2025 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2025
Nov 2024 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 2024
Jan 2023 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2025
Jan 2023 Resolved
TTHM
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2025
Oct 2019 Resolved
Combined Radium (-226 and -228)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2019
Jan 2006 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2006
Jan 2005 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2005
Sep 2004 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Sep 2004
Jan 2004 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
BHC-GAMMA
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Dalapon
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Diquat
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Glyphosate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Di(2-ethylhexyl) phthalate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Picloram
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Hexachlorocyclopentadiene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Jan 2004 Resolved
Atrazine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2004
Showing 20 of 46 violations
Environmental Risk

Flood & disaster history

9
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Pima County has experienced 9 federally declared disasters since 1966. 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
Dec 1990
SEVERE STORMS & FLOODING
Flood FEMA #884
Oct 1983
SEVERE STORMS & FLOODING
Flood FEMA #691
Dec 1978
SEVERE STORMS & FLOODING
Flood FEMA #570
Mar 1978
SEVERE STORMS & FLOODING
Flood FEMA #551

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.9 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 4.1 ppb from 1994 (5.0 ppb) to 2025 (0.9 ppb).
Contaminant Rankings

See how San Xavier West compares by contaminant

Explore where San Xavier West ranks among all Arizona cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Native American
Population Served
1,511
Water Systems
1
Water Source

Where San Xavier West's water comes from

Groundwater

San Xavier West'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 1,511 people through 1 water system.

Infrastructure

Water systems serving San Xavier West

System Name PWSID Population Source
San Xavier West 090400035 1,511 GW
Regional Comparison

How San Xavier West compares

Full Arizona rankings →

San Xavier West's score of 87.9/100 is above the average of 42/100 among major Arizona cities. It outscores 10 of 10 nearby cities.

San Xavier West (this city)
87.9
Phoenix
37.5
Tucson
38.1
Mesa
40.6
Chandler
40.5
Gilbert
34.8
Arizona avg
42
City Profile

About San Xavier West, AZ

Wikipedia →

Sells is an unincorporated community and census-designated place (CDP) in Pima County, Arizona, United States. The population was 2,799 at the 2000 census. It is the capital of the Tohono O'odham Nation and the home of several tribal businesses, such as Tohono O'Odham Ki:Ki Association. It was originally named Indian Oasis by cattle-ranchers/businessmen brothers Joseph and Louis Ménager in 1912. The Ménager brothers also built and ran the Indian Oasis Mercantile Store. The settlement took its present English name in 1918 to honor Indian Commissioner Cato Sells. The O'odham name means "tortoise got wedged".

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Frequently asked questions

Is San Xavier West, AZ tap water safe to drink?

San Xavier West's water quality earned a grade of A- (87.9/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #74 out of 292 cities tested in Arizona.

What contaminants are in San Xavier West's water?

Lead was measured at 0.9 ppb (90th percentile). 46 violations are on record.

How is San Xavier West'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 San Xavier West?

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

Where does San Xavier West's water come from?

San Xavier West's water is sourced from Groundwater. The city has 1 water system serving approximately 1,511 residents.

What health violations has San Xavier West's water system had?

San Xavier West has 3 health-based violations on record. The most recent violation was recorded in November 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 1 violation remains unresolved.

Is San Xavier West's groundwater at risk of contamination?

San Xavier West 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 46 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 San Xavier West's water compare to other cities?

San Xavier West ranks #74 out of 292 cities in Arizona (better than 75% of state cities) and #3775 out of 15744 cities nationally (76th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does San Xavier West's small water system affect quality?

San Xavier West's system serves approximately 1,511 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 46 violations on record.