Is Casa Grande, AZ Tap Water Safe to Drink?
Graded F — but Chromium-6, Strontium and 1 more were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
42.4/100
waterverge.com Casa Grande, AZ — Water Quality Report
Casa Grande's drinking water received a grade of F (42.4 out of 100), indicating failing water quality. The city's 8 water systems serve approximately 140,663 residents using groundwater.
Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 7 PFAS compounds in the water supply.
The system has 1032 violations on record, including 44 health-based violations. 82 remain unresolved.
What to know about Casa Grande's water
Casa Grande ranks #269 out of 292 cities in Arizona for water quality, placing it among the lowest-rated in the state.
Casa Grande 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.
PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.
Hexavalent chromium (chromium-6) was detected at 37.00 µg/L, above California's 10 µg/L limit. There is no federal MCL, but the EPA is reviewing evidence linking long-term exposure to cancer risk.
The system has seen 35 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Casa Grande, AZ water safe to drink?
Casa Grande's drinking water has significant quality concerns based on EPA testing data. With a grade of F (42.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 8 water systems serve approximately 140,663 residents using groundwater (wells).
Recent water quality updates for Casa Grande
A timeline of significant water quality events, violations, and data updates.
Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.
Latest EPA compliance and testing data incorporated into Casa Grande's water quality assessment. Grade: F (42.4/100).
Contaminants: Public Notice.
Contaminants: Lead and Copper Rule.
Contaminants: E. COLI.
Federal disaster declaration (FEMA DR-4203). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Casa Grande's water supply.
Well within EPA limits.
Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.
The "Erin Brockovich" chemical. There is no federal MCL, but California has set a limit of 10 µg/L. Reverse osmosis filtration is effective at removing hexavalent chromium.
PFAS "forever chemicals" detected
UCMR 5 testing found 7 PFAS compounds in Casa Grande's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.
Violation history
Casa Grande's water system has 1,032 total violations on record, including 44 health-based violations. 82 remain unresolved. 35 violations were issued in the last 5 years.
Flood & environmental risk
Maricopa County has experienced 10 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. Local water sources include Salt River.
Where does Casa Grande's water come from?
Casa Grande's drinking water comes from groundwater (wells), supplied by 8 water systems serving approximately 140,663 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Salt River (river).
What Casa Grande residents can do
Recommended: Reverse osmosis system. This addresses the specific contaminants found in Casa Grande'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.
Casa Grande'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 ↓Forever chemicals overview
National PFAS report →Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Casa Grande
Industrial polluters nearby
Reported releases to surface water by facilities near Casa Grande, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
CASA GRANDE DAIRY PRODUCTS LLC CASA GRANDE, AZ85193 | — | — | 2.3 mi |
DAISY BRAND CASA GRANDE, AZ85193 | — | — | 2.4 mi |
FRANKLIN FOODS WEST INC. CASA GRANDE, AZ85193 | — | — | 2.2 mi |
KOHLER CO. CASA GRANDE CASA GRANDE, AZ85193 | — | — | 2.8 mi |
LUCID USA INC. CASA GRANDE, AZ85193 | — | — | 5.2 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Drought conditions
D2 — severe droughtPinal County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Maricopa County has experienced 10 federally declared disasters since 1966. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Casa Grande's water supply, we recommend the following filter types.
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. | 0.0 | 15 | ppb | Inorganic | Safe |
| 11Cl-PF3OUdS | ND | HI | µg/L | PFAS | Not Detected |
| 4:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 6:2 FTS 6:2 FTSPFAS A fluorotelomer sulfonate commonly found at sites contaminated with aqueous film-forming foam (AFFF) used in firefighting. Health EffectsPotential liver toxicity and endocrine disruption. Less studied but identified as a contaminant of concern. EPA LimitNo individual MCL (not yet regulated) Common SourcesFirefighting foam (AFFF), airports, military bases, and industrial facilities. | ND | HI | µg/L | PFAS | Not Detected |
| 8:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 9Cl-PF3ONS | ND | HI | µg/L | PFAS | Not Detected |
| ADONA | ND | HI | µg/L | PFAS | Not Detected |
| HFPO-DA HFPO-DA (GenX)PFAS A replacement for PFOA in manufacturing, marketed as safer but still a persistent "forever chemical." Also known as GenX. Health EffectsLiver and kidney effects, reproductive toxicity, immune system effects, and potential cancer risk. EPA Limit10 ppt MCL Common SourcesFluoropolymer manufacturing (used as PFOA replacement), industrial wastewater discharge. | ND | 0.01 | µg/L | PFAS | Not Detected |
| lithium LithiumInorganic A naturally occurring alkali metal found in groundwater. Monitored under UCMR 5 to assess occurrence in drinking water. Health EffectsKidney effects at high doses. Low-level exposure effects under study; some research suggests neurological effects. EPA LimitNo MCL (monitoring only under UCMR 5) Common SourcesNatural mineral deposits, geothermal water, and industrial discharge. | 353.000 | HI | µg/L | PFAS | Detected |
| NEtFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| NFDHA | ND | HI | µg/L | PFAS | Not Detected |
| NMeFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| PFBA PFBAPFAS One of the shortest-chain PFAS compounds. Very mobile in water and difficult to remove with standard filtration. Health EffectsThyroid effects, potential developmental toxicity. Shorter half-life in body than long-chain PFAS. EPA LimitNo individual MCL (not yet regulated) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and firefighting foam. | 0.020 | HI | µg/L | PFAS | Detected |
| PFBS PFBSPFAS A short-chain PFAS used as a replacement for PFOS. While it clears the body faster than long-chain PFAS, it still persists in the environment. Health EffectsThyroid effects, reproductive and developmental toxicity, kidney effects. EPA LimitPart of Hazard Index (1.0) Common SourcesIndustrial discharge, firefighting foam, and as a replacement chemical in manufacturing. | 0.091 | HI | µg/L | PFAS | Detected |
| PFDA | ND | HI | µg/L | PFAS | Not Detected |
| PFDoA | ND | HI | µg/L | PFAS | Not Detected |
| PFEESA | ND | HI | µg/L | PFAS | Not Detected |
| PFHpA PFHpAPFAS A medium-chain PFAS compound found in various environmental samples. Less studied than PFOA/PFOS but still considered a contaminant of concern. Health EffectsLiver effects, potential developmental toxicity, and endocrine disruption. EPA LimitPart of Hazard Index (1.0) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and contaminated water sources. | 0.009 | HI | µg/L | PFAS | Detected |
| PFHpS | ND | HI | µg/L | PFAS | Not Detected |
| PFHxA PFHxAPFAS A short-chain PFAS replacement chemical widely used after manufacturers phased out longer-chain PFAS. Very commonly detected in water. Health EffectsLiver and kidney effects, potential thyroid disruption. Considered less toxic than long-chain PFAS but still persistent. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial processes, firefighting foam (AFFF), food packaging, and textile treatment. | 0.019 | HI | µg/L | PFAS | Detected |
| PFHxS PFHxSPFAS A medium-chain PFAS found in firefighting foam and consumer products. It has a long half-life in the human body, similar to long-chain PFAS. Health EffectsImmune system effects, thyroid disruption, and potential reproductive and developmental harm. EPA LimitPart of Hazard Index (1.0) Common SourcesFirefighting foam (AFFF), waterproof textiles, food packaging, and industrial discharge. | 0.006 | HI | µg/L | PFAS | Detected |
| PFMBA | ND | HI | µg/L | PFAS | Not Detected |
| PFMPA | ND | HI | µg/L | PFAS | Not Detected |
| PFNA PFNAPFAS A long-chain PFAS compound used in manufacturing fluoropolymers. It bioaccumulates in the body and is very persistent in the environment. Health EffectsDevelopmental effects, liver toxicity, immune suppression, and potential cancer risk. EPA LimitPart of Hazard Index (1.0) Common SourcesFluoropolymer manufacturing, industrial emissions, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFOA PFOAPFAS A long-chain PFAS ("forever chemical") once widely used in nonstick coatings and firefighting foam. It persists in the body and environment for years. Health EffectsLinked to kidney and testicular cancer, thyroid disease, elevated cholesterol, and reproductive issues. EPA Limit4.0 ppt MCL Common SourcesIndustrial discharge, firefighting foam (AFFF), nonstick cookware manufacturing, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFOS PFOSPFAS A long-chain PFAS compound historically used in stain-resistant coatings and firefighting foam. One of the most studied and persistent PFAS chemicals. Health EffectsLiver damage, immune system suppression, thyroid disruption, increased cholesterol, and potential cancer risk. EPA Limit4.0 ppt MCL Common SourcesFirefighting foam (AFFF), industrial sites, stain-resistant fabric treatments, and contaminated groundwater. | ND | 0.004 | µg/L | PFAS | Not Detected |
| PFPeA PFPeAPFAS A short-chain PFAS compound commonly detected in drinking water. One of the most frequently found PFAS in UCMR 5 monitoring. Health EffectsLess studied than PFOA/PFOS. Potential liver and thyroid effects. Research is ongoing. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial discharge, firefighting foam degradation, and consumer products. | 0.021 | HI | µg/L | PFAS | Detected |
| PFPeS | ND | HI | µg/L | PFAS | Not Detected |
| PFTA | ND | HI | µg/L | PFAS | Not Detected |
| PFTrDA | ND | HI | µg/L | PFAS | Not Detected |
| PFUnA | ND | HI | µg/L | PFAS | Not Detected |
Lead level trend (90th percentile)
See how Casa Grande compares by contaminant
Explore where Casa Grande ranks among all Arizona cities for specific contaminants.
Water source & infrastructure
Where Casa Grande's water comes from
Casa Grande'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 private ownership and serves approximately 140,663 people through 8 water systems.
Water bodies near Casa Grande
Casa Grande is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Casa Grande
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ARIZONA WATER CO - PINAL VALLEY | AZ0411009 | 134,432 | GW |
| PICACHO WATER COMPANY | AZ0411135 | 2,440 | GW |
| ARIZONA WATER CO - TIERRA GRANDE | AZ0411076 | 1,796 | GW |
| AWC - CASA GRANDE WEST WATER COMPANY | AZ0411024 | 943 | GW |
| ARIZONA WATER CO - STANFIELD | AZ0411012 | 639 | GW |
| SIERRA VISTA RV PARK | AZ0411383 | 200 | GW |
| AWC - CASA GRANDE SOUTH WATER COMPANY | AZ0411061 | 176 | GWP |
| GW SANTA CRUZ WATER - CP WATER CO | AZ0411151 | 37 | GWP |
How Casa Grande compares
Full Arizona rankings →Casa Grande's score of 42.4/100 is on par with the average of 42/100 among major Arizona cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Arizona rankings →About Casa Grande, AZ
Wikipedia →Phoenix is the capital and most populous city of the U.S. state of Arizona. With over 1.6 million residents at the 2020 census, Phoenix is the fifth-most populous city in the United States and the most populous state capital. The Phoenix metropolitan area, with an estimated 5.19 million residents, is the tenth-most populous metropolitan area in the U.S. and the most populous in the Mountain states and Southwest. Phoenix is the county seat of Maricopa County in the Salt River Valley and Arizona Sun Corridor and, with an area of 517.9 square miles, is the largest city by area in Arizona and 11th-largest city by area in the United States.
Learn more about your water
Guides and resources related to Casa Grande's water quality findings.
Explore water quality across Pinal
Frequently asked questions
Is Casa Grande, AZ tap water safe to drink?
Casa Grande's water quality earned a grade of F (42.4/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #269 out of 292 cities tested in Arizona.
What contaminants are in Casa Grande's water?
Lead was measured at 0.0 ppb (90th percentile). 7 PFAS compounds were detected. 1032 violations are on record.
How is Casa Grande'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 Casa Grande?
PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.
Where does Casa Grande's water come from?
Casa Grande's water is sourced from Groundwater. The city has 8 water systems serving approximately 140,663 residents.
What health violations has Casa Grande's water system had?
Casa Grande has 44 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. 82 violations remain unresolved.
Is Casa Grande's groundwater at risk of contamination?
Casa Grande 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 1032 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.
Why does Casa Grande have so many PFAS compounds in its water?
7 different PFAS "forever chemical" compounds were detected in Casa Grande's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. While detected, current levels are within EPA limits. An activated carbon filter can further reduce exposure.
How does Casa Grande's water compare to other cities?
Casa Grande ranks #269 out of 292 cities in Arizona (better than 8% of state cities) and #14806 out of 15744 cities nationally (6th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.