Pima County Water Quality: 4 Cities Ranked by the Records
Pima County, Arizona: 4 city reports built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.
Highest result for each contaminant
One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.
LithiumDetected in 4 systems10 µg/L EPA health reference level (screening, not a legal limit) · US EPAHighest166 µg/L
- COMMUNITY WC OF GREEN VALLEY166 µg/LSample date: 2023-12-18 to 2024-06-19
- SAHUARITA WATER COMPANY130 µg/LSample date: 2023-11-16 to 2024-05-15
- City of Tucson (Tucson Water)63.7 µg/LSample date: 2024-01-10 to 2025-11-04
- METROPOLITAN DWID18.3 µg/LSample date: 2024-05-08 to 2025-05-14
Perfluorohexanesulfonic acid (PFHxS)Detected in 1 system of 4 tested10 ng/L federal MCL (2024) · US EPAHighest3.9 ng/L
- METROPOLITAN DWID3.9 ng/LSample date: 2024-05-08 to 2025-05-14
- City of Tucson (Tucson Water)Not detected · below 3.0 ng/L lab reporting limitSample date: 2024-01-10 to 2025-11-04
- COMMUNITY WC OF GREEN VALLEYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-12-18 to 2025-04-09
- SAHUARITA WATER COMPANYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-11-16 to 2024-05-15
Lead (90th percentile)Detected in 2 systems of 4 tested15 µg/L federal action level · US EPAHighest0.649 µg/L
- City of Tucson (Tucson Water)0.649 µg/LMonitoring period: 2021–2023
- METROPOLITAN DWID0.57 µg/LMonitoring period: 2023–2025
- COMMUNITY WC OF GREEN VALLEYNot detectedMonitoring period: 2022–2024
- SAHUARITA WATER COMPANYNot detectedMonitoring period: 2023–2025
Perfluorobutanesulfonic acid (PFBS)Detected in 1 system of 4 tested2,000 ng/L EPA health advisory (screening, not a legal limit) · US EPAHighest4.8 ng/L
- METROPOLITAN DWID4.8 ng/LSample date: 2024-05-08 to 2025-05-14
- City of Tucson (Tucson Water)Not detected · below 3.0 ng/L lab reporting limitSample date: 2024-01-10 to 2025-11-04
- COMMUNITY WC OF GREEN VALLEYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-12-18 to 2025-04-09
- SAHUARITA WATER COMPANYNot detected · below 3.0 ng/L lab reporting limitSample date: 2023-11-16 to 2024-05-15
Perfluorobutanoic acid (PFBA)Detected in 1 system of 4 testedNo federal or state limit; shown for transparencyHighest8.1 ng/L
- City of Tucson (Tucson Water)8.1 ng/LSample date: 2024-01-10 to 2025-11-04
- COMMUNITY WC OF GREEN VALLEYNot detected · below 5.0 ng/L lab reporting limitSample date: 2023-12-18 to 2025-04-09
- METROPOLITAN DWIDNot detected · below 5.0 ng/L lab reporting limitSample date: 2024-05-08 to 2025-05-14
- SAHUARITA WATER COMPANYNot detected · below 5.0 ng/L lab reporting limitSample date: 2023-11-16 to 2024-05-15
26 PFAS tested, none detected in any systemShow
Tested in these 4 systems: City of Tucson (Tucson Water), COMMUNITY WC OF GREEN VALLEY, METROPOLITAN DWID, SAHUARITA WATER COMPANY
- 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
- 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
- 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
- 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
- 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
- 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
- Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
- N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
- N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
- Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
- Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
- Perfluoro-3-methoxypropanoic acid (PFMPA)
- Perfluoro-4-methoxybutanoic acid (PFMBA)
- Perfluorodecanoic acid (PFDA)
- Perfluorododecanoic acid (PFDoA)
- Perfluoroheptanesulfonic acid (PFHpS)
- Perfluoroheptanoic acid (PFHpA)
- Perfluorohexanoic acid (PFHxA)
- Perfluorononanoic acid (PFNA)
- Perfluorooctanesulfonic acid (PFOS)
- Perfluorooctanoic acid (PFOA)
- Perfluoropentanesulfonic acid (PFPeS)
- Perfluoropentanoic acid (PFPeA)
- Perfluorotetradecanoic acid (PFTA)
- Perfluorotridecanoic acid (PFTrDA)
- Perfluoroundecanoic acid (PFUnA)
Cities ranked by the records
Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.
0of 4 cities above the 15 µg/L action level
Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.
Lead in Arizona1city reports hardness · Tucson, 12.4 gpg
Hard on the USGS scale. An aesthetic measure with no federal health limit.
Hard water explainedLargest water systems
- TucsonTUCSON CITY OF · AZ0410112732,906 served
- Casas AdobesMETROPOLITAN DWID · AZ041007645,570 served
- Green ValleyCOMMUNITY WC OF GREEN VALLEY · AZ041000422,085 served
- SahuaritaSAHUARITA WATER COMPANY · AZ041031218,178 served
Frequently asked
How does Pima County tap water compare across cities?
PurityMap ranks 4 cities in Pima County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Green Valley's main water system: COMMUNITY WC OF GREEN VALLEY · PWSID AZ0410004 · Purity Score 100 (Excellent) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.
How many Pima County cities had a PFAS sample above a 2024 EPA limit?
None of the 4 Pima County city reports had a PFAS sample above a 2024 EPA limit in EPA's UCMR 5 testing. PFAS were detected below the limit in 2.
Is there lead in Pima County tap water?
Utilities report lead as a 90th-percentile result from home taps. 2 of 4 Pima County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
Does Pima County have hard water?
Hardness is published in utility water-quality reports for 1 Pima County city on record; the hardest is Tucson at 12.4 grains per gallon. Hardness affects scale and appliances; it is not a health finding.
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