Is Standing Rock, AZ Tap Water Safe to Drink?
Graded A-, with 4 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
89.1/100
waterverge.com Standing Rock, AZ — Water Quality Report
Standing Rock's drinking water received a grade of A- (89.1 out of 100), indicating good water quality. The city's 1 water system serves approximately 739 residents using groundwater.
Lead levels were measured at 2.5 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 77 violations on record, including 0 health-based violations. 4 remain unresolved.
What to know about Standing Rock's water
Standing Rock ranks #66 out of 292 cities in Arizona for water quality, placing it above average in the state.
Standing Rock 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, Standing Rock may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Standing Rock, AZ water safe to drink?
Standing Rock's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (89.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 739 residents using groundwater (wells).
Recent water quality updates for Standing Rock
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Standing Rock's water quality assessment. Grade: A- (89.1/100).
Contaminants: E. COLI.
Federal disaster declaration (FEMA DR-4620). Flood event — may have impacted local water infrastructure.
Contaminants: Total Haloacetic Acids (HAA5), TTHM.
Contaminants: Revised Total Coliform Rule.
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 Standing Rock's water supply.
Well within EPA limits.
Violation history
Standing Rock's water system has 77 total violations on record, including 0 health-based violations. 4 remain unresolved. 1 violation was issued in the last 5 years.
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.
Where does Standing Rock's water come from?
Standing Rock's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 739 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Standing Rock residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Standing Rock's water.
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.
Standing Rock'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
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.
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. | 2.5 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Standing Rock compares by contaminant
Explore where Standing Rock ranks among all Arizona cities for specific contaminants.
Water source & infrastructure
Where Standing Rock's water comes from
Standing Rock'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 739 people through 1 water system.
Water systems serving Standing Rock
| System Name | PWSID | Population | Source |
|---|---|---|---|
| Standing Rock NTUA | NN3503029 | 739 | GW |
How Standing Rock compares
Full Arizona rankings →Standing Rock's score of 89.1/100 is above the average of 42/100 among major Arizona cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Arizona rankings →About Standing Rock, AZ
Wikipedia →Window Rock, known in Navajo as Tségháhoodzání, is a city and census-designated place that serves as the capital of the Navajo Nation, the largest Native American tribe by both land and tribal enrollment. The capital lies within the boundaries of the St. Michaels Chapter, adjacent to the Arizona and New Mexico state line. Window Rock is the site of the Navajo Nation governmental campus, which contains the Navajo Nation Council, Navajo Nation Supreme Court, the offices of the Navajo Nation President and Vice President, and many Navajo government buildings.
Learn more about your water
Guides and resources related to Standing Rock's water quality findings.
Frequently asked questions
Is Standing Rock, AZ tap water safe to drink?
Standing Rock's water quality earned a grade of A- (89.1/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #66 out of 292 cities tested in Arizona.
What contaminants are in Standing Rock's water?
Lead was measured at 2.5 ppb (90th percentile). 77 violations are on record.
How is Standing Rock'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 Standing Rock?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Standing Rock's water come from?
Standing Rock's water is sourced from Groundwater. The city has 1 water system serving approximately 739 residents.
Is Standing Rock's groundwater at risk of contamination?
Standing Rock 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 77 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 Standing Rock's water compare to other cities?
Standing Rock ranks #66 out of 292 cities in Arizona (better than 77% of state cities) and #3055 out of 15744 cities nationally (81th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Standing Rock's small water system affect quality?
Standing Rock's system serves approximately 739 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 77 violations on record.