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Tap water quality report

Johnson Ranch, AZ

EPA monitoring detected 22 contaminants across the 2 water suppliers serving Johnson Ranch. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

2
water suppliers
97,797
people served
22
contaminants found
Arizona rankings Lead in Arizona PFAS in Arizona

What was found in Johnson Ranch's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
10200 µg/L 102%
of the EPA limit, at the 95th percentile of samples — 10000 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2019
2/2 SYR4
Nitrate-Nitrite
9760 µg/L 98%
of the EPA limit 10000 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2019
2/2 SYR4
Fluoride
1300 µg/L 33%
of the EPA limit 4000 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
2/2 SYR4
Lithium
185 µg/L
No EPA limit set
Main supplier: EPCOR - SAN TAN · 87,435 people · 2025
2/2 UCMR-5
Copper
117 µg/L 9%
of the EPA limit 1300 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
Highest in the city: 162.5 µg/L — EPCOR - SAN TAN ANTHEM · 10,362 people · 2017
2/2 SYR4
Barium
56 µg/L 2.8%
of the EPA limit 2000 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
2/2 SYR4
TTHM
11.2 µg/L 14%
of the EPA limit 80 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2019
2/2 SYR4
Combined Uranium
9.805 µg/L 33%
of the EPA limit 30 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2016
1/2 SYR4
Selenium
8 µg/L 16%
of the EPA limit 50 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
1/2 SYR4
Lead
7.52 µg/L 50%
of the EPA limit 15 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
Highest in the city: 7.845 µg/L — EPCOR - SAN TAN ANTHEM · 10,362 people · 2017
2/2 SYR4
Arsenic
6.8 µg/L 68%
of the EPA limit 10 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
2/2 SYR4
Chromium
6.8 µg/L 6.8%
of the EPA limit 100 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
2/2 SYR4
Gross Alpha, Excl. Radon And U
6.475 pCi/L 43%
of the EPA limit 15 pCi/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2016
1/2 SYR4
Combined Radium (-226 And -228)
4.875 pCi/L 98%
of the EPA limit 5 pCi/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2018
1/2 SYR4
Total Haloacetic Acids (HAA5)
4.34 µg/L 7.2%
of the EPA limit 60 µg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2019
2/2 SYR4
Pfpea
0.0400 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
PFBS
0.0240 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
Pfhxa
0.0220 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
PFOA
0.0190 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
Pfba
0.0067 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
Pfhpa
0.0046 µg/L
No EPA limit set
Highest in the city: EPCOR - SAN TAN ANTHEM · 10,362 people · 2025
1/2 UCMR-5
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
Main supplier: EPCOR - SAN TAN · 87,435 people · 2024
2/2 LCR
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 the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Johnson Ranch

SupplierPopulation served
EPCOR - SAN TAN 87,435
EPCOR - SAN TAN ANTHEM 10,362

Frequently asked questions about Johnson Ranch tap water

Is Johnson Ranch tap water safe to drink?

EPA testing detected 22 contaminants in the water serving Johnson Ranch. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Johnson Ranch?

2 public water suppliers report drinking-water monitoring for Johnson Ranch, Arizona to the EPA. Each is listed above with its population served.

What contaminants are in Johnson Ranch's water?

The contaminants EPA monitoring detected in Johnson Ranch include Nitrate, Nitrate-Nitrite, Fluoride, Lithium, Copper. The full list, with the level at the main supplier and the data source, is in the table above.

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.