Water Quality: Flagstaff, AZ

13 water systems • 93,774 people served

Multiple Health Violations
810
Total Violations
81
Health-Based Violations
13
Water Systems
93,774
Population Served

Water Quality Summary

Flagstaff is served by 13 public water systems with a combined service population of 93,774 people, and has 810 EPA Safe Drinking Water Act violations on record. Critically, 81 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Flagstaff's violation count is 113% above the national average for Arizona. Contaminants associated with violations include Barium, Chlorine Dioxide, E. coli, Fecal Coliform, Stage 2 DBP.

Contaminants Found

Barium

Increases blood pressure and causes cardiovascular effects with long-term exposure.

Common source: Natural rock deposits, oil drilling operations, coal power plant waste

EPA limit: 2 mg/L

Chlorine Dioxide

Can cause anemia in infants and young children; may cause nervous system effects at high levels.

Common source: Water treatment disinfectant used to control taste, odor, and microorganisms

EPA limit: 0.8 mg/L

E. coli

Causes gastrointestinal illness; certain strains (e.g., O157:H7) can cause severe kidney failure and death.

Common source: Fecal contamination from humans or animals entering the water supply

EPA limit: Zero (no E. coli permitted in drinking water)

Fecal Coliform

Indicates direct fecal contamination; associated with diarrhea, cramps, nausea, and potential severe illness.

Common source: Human and animal fecal waste

EPA limit: Zero tolerance (any positive triggers violations)

Stage 2 DBP

Trihalomethanes and haloacetic acids that increase cancer risk and may cause adverse reproductive outcomes.

Common source: Chlorine disinfection reacting with natural organic matter in source water

EPA limit: TTHM: 0.080 mg/L; HAA5: 0.060 mg/L

TTHM

Total trihalomethanes are linked to increased risk of bladder cancer and adverse reproductive outcomes.

Common source: Reaction of chlorine disinfectants with naturally occurring organic matter in water

EPA limit: 0.080 mg/L (80 ppb)

Total Haloacetic Acids (HAA5)

Haloacetic acids are associated with increased cancer risk and potential reproductive and developmental effects.

Common source: Reaction of chlorine disinfectants with organic matter in treated water

EPA limit: 0.060 mg/L (60 ppb)

Water Systems Serving Flagstaff

System Name PWSID Source Population Violations
FLAGSTAFF CITY OF AZ0403008 Surface Water 76,960 351
DONEY PARK WATER AZ0403005 Groundwater 8,996 16
KACHINA VILLAGE DWID AZ0403013 Groundwater 3,500 23
FOREST HIGHLANDS WATER COMPANY AZ0403073 Groundwater 1,668 16
PONDEROSA UTILITY CORP AZ0403018 Groundwater 1,585 23
MOUNTAIN DELL WATER INC AZ0403015 Groundwater 250 36
PAINTED DESERT DEMO PROJECT STAR SCHOOL AZ0403385 Groundwater 250 10
GREEN VALLEY MHP AZ0413348 Groundwater 190 116
LAKE MARY COUNTRY STORE AZ0403067 Groundwater 130 34
HECKETHORN WATER COMPANY AZ0403011 Groundwater 90 43
USFS KNF TUSAYAN ADMIN AZ0403659 Groundwater 80 79
A1 RANCH DWID AZ0403087 Groundwater 45 35
LOCKETT ESTATES AZ0403175 Groundwater 30 28

Concerned About Your Water?

A home water filter can remove common contaminants. NSF-certified filters are tested against EPA standards.

Consider a reverse osmosis system for comprehensive filtration or a carbon filter for basic improvement.

Other Cities in Arizona

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Data Sources

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). Data includes all recorded violations for active community water systems.

Verify at epa.govSearch ECHO for AZ