Tap WaterIndex

Tap water quality report

Tucson City of

EPA monitoring tested this supplier for 104 contaminants and detected 26. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

104
contaminants tested
26
detected
732,906
people served
1
health-based violations
Water source
Ground water
Ownership
Local government
Counties served
Pima

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

1
health-based violations
2,273
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Archived 1980-11-19 → 1981-03-18
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31
MR Monitoring Archived 2026-01-01 → 2026-03-31

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfba 0.0081 µg/L 1/163 2025

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
7890 µg/L 79%
of the EPA limit 10000 µg/L
 1958/1984 SYR4 2012–2019
Fluoride
1170 µg/L 29%
of the EPA limit 4000 µg/L
 344/354 SYR4 2013–2019
Barium
157 µg/L 7.9%
of the EPA limit 2000 µg/L
 336/354 SYR4 2013–2019
Arsenic
8 µg/L 80%
of the EPA limit 10 µg/L
 278/353 SYR4 2013–2019
TTHM
48 µg/L 60%
of the EPA limit 80 µg/L
 236/248 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
11 µg/L 18%
of the EPA limit 60 µg/L
 167/248 SYR4 2012–2019
Combined Uranium
22.648 µg/L 75%
of the EPA limit 30 µg/L
 133/148 SYR4 2013–2019
Nitrate-Nitrite
6400 µg/L 64%
of the EPA limit 10000 µg/L
 129/132 SYR4 2013–2019
Lithium
63.7 µg/L
No EPA limit set
 112/163 UCMR-5 2025
Copper
584 µg/L 45%
of the EPA limit 1300 µg/L
 110/110 SYR4 2014–2017
Selenium
6.18 µg/L 12%
of the EPA limit 50 µg/L
 107/354 SYR4 2013–2019
Gross Alpha, Excl. Radon And U
3.9 pCi/L 26%
of the EPA limit 15 pCi/L
 98/148 SYR4 2013–2019
Lead
223 µg/L 1487%
of the EPA limit, in the worst sample — 15 µg/L
 96/110 SYR4 2014–2017
Combined Radium (-226 And -228)
1.3 pCi/L 26%
of the EPA limit 5 pCi/L
 13/148 SYR4 2013–2019
Lead
0.00065 mg/L 4.3%
of the EPA limit 0.0150 mg/L
 10/10 LCR 2023
Simazine
0.1100 µg/L 2.8%
of the EPA limit 4 µg/L
 8/365 SYR4 2012–2019
Atrazine
0.1100 µg/L 3.7%
of the EPA limit 3 µg/L
 7/359 SYR4 2013–2019
Trichloroethylene
2.5 µg/L 50%
of the EPA limit 5 µg/L
 7/416 SYR4 2012–2019
Di(2-ethylhexyl) Phthalate
4.4 µg/L 73%
of the EPA limit 6 µg/L
 5/372 SYR4 2012–2019
Xylenes, Total
8 µg/L 0.1%
of the EPA limit 10000 µg/L
 4/416 SYR4 2012–2019
Cyanide
9.1 µg/L 4.6%
of the EPA limit 200 µg/L
 3/355 SYR4 2013–2019
1,1-Dichloroethylene
1.8 µg/L 26%
of the EPA limit 7 µg/L
 1/415 SYR4 2012–2019
Antimony, Total
1.8 µg/L 30%
of the EPA limit 6 µg/L
 1/354 SYR4 2013–2019
Ethylbenzene
1.1 µg/L 0.2%
of the EPA limit 700 µg/L
 1/416 SYR4 2012–2019
Pentachlorophenol
0.1200 µg/L 12%
of the EPA limit 1 µg/L
 1/358 SYR4 2012–2019
78 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAsbestosBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDinosebDiquatEthylene DibromideEndothallEndrinGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPicloramStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneVinyl Chloridecis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Frequently asked questions about Tucson City of

Is Tucson City of tap water safe to drink?

EPA monitoring detected 26 contaminants in Tucson City of's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Tucson City of's water?

EPA monitoring detected Nitrate, Fluoride, Barium, Arsenic, TTHM, and others. The full list with the level and data source for each is above.

How many people does Tucson City of serve?

Tucson City of reports serving 732,906 people, per its EPA record.

Has Tucson City of had any water quality violations?

The EPA has 2273 violations on file for Tucson City of, of which 1 is health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.