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.
0
health-based violations
54
violations on file
0
still open
| Violation | Type | Status | Period |
|---|---|---|---|
| MR | Monitoring | Archived | 2026-01-01 → 2026-03-31 |
| MR | Monitoring | Archived | 2026-01-01 → 2026-03-31 |
| MR | Monitoring | Resolved | 2020-07-01 → 2020-09-30 |
| MR | Monitoring | Resolved | 2020-07-01 → 2020-09-30 |
| MR | Monitoring | Resolved | 2020-04-01 → 2020-06-30 |
| MR | Monitoring | Resolved | 2020-04-01 → 2020-06-30 |
| MR | Monitoring | Resolved | 2020-01-01 → 2020-03-31 |
| MR | Monitoring | Resolved | 2020-01-01 → 2020-03-31 |
| MR | Monitoring | Resolved | 2019-10-01 → 2019-12-31 |
| MR | Monitoring | Resolved | 2019-10-01 → 2019-12-31 |
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 95th percentile of this
system's samples — over 100% is worth reading, but is not by itself a
violation. Where a single sample came in higher than that percentile, it
is noted under the bar. Formal violations are listed separately.
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Nitrate | 710 µg/L 7.1% of the EPA limit 10000 µg/L
worst single sample: 1240 µg/L | 84/84 | SYR4 | 2012–2019 |
| Copper | 110.3 µg/L 8.5% of the EPA limit 1300 µg/L
worst single sample: 250 µg/L | 78/79 | SYR4 | 2012–2018 |
| TTHM | 29.355 µg/L 37% of the EPA limit 80 µg/L
worst single sample: 38.2 µg/L | 74/74 | SYR4 | 2012–2019 |
| Barium | 250 µg/L 13% of the EPA limit 2000 µg/L
worst single sample: 260 µg/L | 36/36 | SYR4 | 2012–2019 |
| Chromium | 25.25 µg/L 25% of the EPA limit 100 µg/L
worst single sample: 27 µg/L | 36/36 | SYR4 | 2012–2019 |
| Fluoride | 822.5 µg/L 21% of the EPA limit 4000 µg/L
worst single sample: 1200 µg/L | 36/36 | SYR4 | 2012–2019 |
| Arsenic | 6.32 µg/L 63% of the EPA limit 10 µg/L
worst single sample: 10 µg/L | 35/36 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 703 µg/L 7% of the EPA limit 10000 µg/L
worst single sample: 1240 µg/L | 35/35 | SYR4 | 2012–2019 |
| Selenium | 4.52 µg/L 9% of the EPA limit 50 µg/L
worst single sample: 5 µg/L | 17/36 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 4.88 µg/L 8.1% of the EPA limit 60 µg/L
worst single sample: 5.9 µg/L | 13/74 | SYR4 | 2012–2019 |
| Bromodichloromethane | 10.035 µg/L No EPA limit set
worst single sample: 10.8 µg/L | 10/10 | SYR4 | 2019 |
| Bromoform | 6.32 µg/L No EPA limit set
worst single sample: 7.4 µg/L | 10/10 | SYR4 | 2019 |
| Dibromochloromethane | 14.515 µg/L No EPA limit set
worst single sample: 15.1 µg/L | 10/10 | SYR4 | 2019 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L | 10/10 | LCR | 2024 |
| Chloroform | 2.52 µg/L No EPA limit set
worst single sample: 3 µg/L | 9/10 | SYR4 | 2019 |
| Combined Uranium | 2.52 µg/L 8.4% of the EPA limit 30 µg/L
worst single sample: 2.6 µg/L | 9/9 | SYR4 | 2013–2019 |
| Lead | 26.1 µg/L 174% of the EPA limit, at the 95th percentile of samples — 15 µg/L
worst single sample: 31 µg/L | 8/79 | SYR4 | 2012–2018 |
| Gross Alpha, Excl. Radon And U | 2.06 pCi/L 14% of the EPA limit 15 pCi/L
worst single sample: 2.1 pCi/L | 5/9 | SYR4 | 2013–2019 |
| Combined Radium (-226 And -228) | 0.8900 pCi/L 18% of the EPA limit 5 pCi/L
worst single sample: 0.9000 pCi/L | 3/31 | SYR4 | 2012–2019 |
| Dibromoacetic Acid | 1.665 µg/L No EPA limit set
worst single sample: 1.7 µg/L | 2/10 | SYR4 | 2019 |
| Lithium | 51 µg/L No EPA limit set | 2/2 | UCMR-5 | 2025 |
| Dichloroacetic Acid | 1.3 µg/L No EPA limit set | 1/10 | SYR4 | 2019 |
| Ethylbenzene | 1.6 µg/L 0.2% of the EPA limit 700 µg/L | 1/38 | SYR4 | 2012–2019 |
| Xylenes, Total | 16.1 µg/L 0.2% of the EPA limit 10000 µg/L | 1/38 | SYR4 | 2012–2019 |
89 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-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-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinGlyphosateGross Beta Particle ActivityHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroacetic AcidTrichloroethyleneVinyl Chloridecis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about Desert Oasis
Is Desert Oasis tap water safe to drink?
EPA monitoring detected 24 contaminants in Desert Oasis'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 Desert Oasis's water?
EPA monitoring detected Nitrate, Copper, TTHM, Barium, Chromium, and others. The full list with the level and data source for each is above.
How many people does Desert Oasis serve?
Desert Oasis reports serving 23,963 people in Arizona, per its EPA record.
Has Desert Oasis had any water quality violations?
The EPA has 54 violations on file for Desert Oasis, of which 0 are 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.