Is Sr Boarding School, Sr Subdivision, Palo, 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 ↓
94.3/100
waterverge.com Sr Boarding School, Sr Subdivision, Palo, AZ — Water Quality Report
Sr Boarding School, Sr Subdivision, Palo's drinking water received a grade of A (94.3 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,623 residents using groundwater.
Lead levels were measured at 0.5 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 44 violations on record, including 2 health-based violations. 1 remains unresolved.
What to know about Sr Boarding School, Sr Subdivision, Palo's water
Sr Boarding School, Sr Subdivision, Palo ranks #4 out of 292 cities in Arizona for water quality, placing it one of the best in the state.
Sr Boarding School, Sr Subdivision, Palo 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, Sr Boarding School, Sr Subdivision, Palo may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Sr Boarding School, Sr Subdivision, Palo, AZ water safe to drink?
Sr Boarding School, Sr Subdivision, Palo's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (94.3/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 1,623 residents using groundwater (wells).
Recent water quality updates for Sr Boarding School, Sr Subdivision, Palo
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Sr Boarding School, Sr Subdivision, Palo's water quality assessment. Grade: A (94.3/100).
Contaminants: Arsenic.
Contaminants: Arsenic.
Contaminants: Combined Uranium, Gross Alpha, Excl. Radon and U, Combined Radium (-226 and -228).
Federal disaster declaration (FEMA DR-3241). Hurricane event — may have impacted local water infrastructure.
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 Sr Boarding School, Sr Subdivision, Palo's water supply.
Well within EPA limits.
Violation history
Sr Boarding School, Sr Subdivision, Palo's water system has 44 total violations on record, including 2 health-based violations. 1 remain unresolved.
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.
Where does Sr Boarding School, Sr Subdivision, Palo's water come from?
Sr Boarding School, Sr Subdivision, Palo's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,623 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Sr Boarding School, Sr Subdivision, Palo residents can do
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.
Sr Boarding School, Sr Subdivision, Palo'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.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Flood & disaster history
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.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.5 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Sr Boarding School, Sr Subdivision, Palo compares by contaminant
Explore where Sr Boarding School, Sr Subdivision, Palo ranks among all Arizona cities for specific contaminants.
Water source & infrastructure
Where Sr Boarding School, Sr Subdivision, Palo's water comes from
Sr Boarding School, Sr Subdivision, Palo'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 1,623 people through 1 water system.
Water systems serving Sr Boarding School, Sr Subdivision, Palo
| System Name | PWSID | Population | Source |
|---|---|---|---|
| Greater Santa Rosa Regional | 090400226 | 1,623 | GW |
How Sr Boarding School, Sr Subdivision, Palo compares
Full Arizona rankings →Sr Boarding School, Sr Subdivision, Palo's score of 94.3/100 is above the average of 42/100 among major Arizona cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Arizona rankings →About Sr Boarding School, Sr Subdivision, Palo, 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".
Learn more about your water
Guides and resources related to Sr Boarding School, Sr Subdivision, Palo's water quality findings.
Frequently asked questions
Is Sr Boarding School, Sr Subdivision, Palo, AZ tap water safe to drink?
Sr Boarding School, Sr Subdivision, Palo's water quality earned a grade of A (94.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #4 out of 292 cities tested in Arizona.
What contaminants are in Sr Boarding School, Sr Subdivision, Palo's water?
Lead was measured at 0.5 ppb (90th percentile). 44 violations are on record.
How is Sr Boarding School, Sr Subdivision, Palo'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 Sr Boarding School, Sr Subdivision, Palo?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Sr Boarding School, Sr Subdivision, Palo's water come from?
Sr Boarding School, Sr Subdivision, Palo's water is sourced from Groundwater. The city has 1 water system serving approximately 1,623 residents.
What health violations has Sr Boarding School, Sr Subdivision, Palo's water system had?
Sr Boarding School, Sr Subdivision, Palo has 2 health-based violations on record. The most recent violation was recorded in July 2017. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 1 violation remains unresolved.
Is Sr Boarding School, Sr Subdivision, Palo's groundwater at risk of contamination?
Sr Boarding School, Sr Subdivision, Palo 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 44 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 Sr Boarding School, Sr Subdivision, Palo's water compare to other cities?
Sr Boarding School, Sr Subdivision, Palo ranks #4 out of 292 cities in Arizona (better than 99% of state cities) and #542 out of 15744 cities nationally (97th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Sr Boarding School, Sr Subdivision, Palo's small water system affect quality?
Sr Boarding School, Sr Subdivision, Palo's system serves approximately 1,623 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 44 violations on record.