Tap Water Quality Report

Tap water quality in JOHNSON RANCH, Arizona

Served by EPCOR - SAN TAN. 87,435 residents.

Average score 58/100
Utilities 1
Population 87,435
Quick answer

Tap water in JOHNSON RANCH, Arizona receives a grade of F (58/100) from TapWaterSafety.org. It's served by EPCOR - SAN TAN. The most significant water quality concerns are: Arsenic significantly above health guideline; Chromium (hexavalent) significantly above health guideline; Nitrate and nitrite significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?

What's in JOHNSON RANCH's tap water

Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving JOHNSON RANCH.

Arsenic significantly above health guideline

Moderate concern

Arsenic detected at 3.78 ppb, 946x above the EWG health guideline of 0.004 ppb.

Chromium (hexavalent) significantly above health guideline

Moderate concern

Chromium (hexavalent) detected at 3.47 ppb, 173x above the EWG health guideline of 0.02 ppb.

Nitrate and nitrite significantly above health guideline

Moderate concern

Nitrate and nitrite detected at 6.21 ppm, 44x above the EWG health guideline of 0.14 ppm.

Recommended filters for JOHNSON RANCH

Filters matched to the specific contaminants in JOHNSON RANCH's water supply.

Reverse Osmosis

$249-$750

Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

All contaminants detected in JOHNSON RANCH's tap water

Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Arsenic
Heavy metal
3.78 ppb 0.004 10.0 10 10 0.004 946× over
Chromium (hexavalent)
Heavy metal
3.47 ppb 0.02 173× over
Nitrate and nitrite
Inorganic
6.21 ppm 0.14 10.0 11.3 11.3 10 44× over
Nitrate
Inorganic
5.81 ppm 0.14 10.0 11.3 11.3 10 41× over
Haloacetic acids (HAA9)
Disinfection byproduct
1.02 ppb 0.06 17× over
Uranium
Radiological
4.89 pCi/L 0.43 20.0 30 30 0.43 11× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
1.29 ppb 0.15 80.0 100 8.6× over
Radium, combined (-226 and -228)
Radiological
0.31 pCi/L 0.05 5.0 6.1× over
Dibromochloromethane
Disinfection byproduct
0.375 ppb 0.1 3.8× over
Bromoform
Disinfection byproduct
1.15 ppb 0.5 2.3× over
Vanadium
Other
13.6 ppb 21.0 Below guideline
Barium
Heavy metal
40.5 ppb 700.0 2000.0 1300 2000 Below guideline
Molybdenum
Other
1.5 ppb 40.0 Below guideline
Selenium
Heavy metal
1.07 ppb 30.0 50.0 20 40 30 Below guideline
Manganese
Heavy metal
1.04 ppb 100.0 50 80 Below guideline
Chlorate
Disinfection byproduct
2.0 ppb 210.0 Below guideline
Strontium
Radiological
0.83 ppb 1500.0 Below guideline
Chromium (total)
Heavy metal
3.37 ppb 100.0 Below guideline
Fluoride
Inorganic
0.453 ppm 4.0 1.5 1.5 Below guideline
Germanium
Other
0.385 ppb Below guideline
Lithium
Other
112.7 ppb Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.

Treatment plant contact info

For service issues, water quality concerns, or to request a Consumer Confidence Report from EPCOR - SAN TAN.

Treatment Plant

FacilityTP023 - CL2, GAS

ZIP codes served

JOHNSON RANCH's public water systems serve the following ZIP codes: