Your local water, explained
Start with Tucson Water. Confirm the system on your bill.
This Pima County guide starts with Tucson Water’s Main System and keeps its measurements separate from other providers. Tucson Water identifies hard water in its guidance, so softening is worth evaluating for scale. Use a current hardness test for sizing rather than a made-up county average.
Start with the report. Then match it to your home.
Match your water bill
Choose the provider printed on your bill. The city in your mailing address may differ.
Confirm the provider above, or choose Other / not sure.
Utility results are not a test of your tap. Sources checked October 29, 2026.
| Provider | Hardness context |
|---|---|
| Tucson Water — Main System | Hard — utility guidance — Tucson Water confirms hard water in its guidance. This report does not supply a single numeric hardness value for the main system. Check the neighborhood dashboard or test your incoming water. |
2025 report · sample years shown below
Each label names its benchmark. Below a legal limit does not mean zero or a test of your home.
Numeric result varies
Tucson Water confirms hard water in its guidance. This report does not supply a single numeric hardness value for the main system. Check the neighborhood dashboard or test your incoming water.
1.0 mg/L
Reported result · 2025; range 0.94–1.07. 4 mg/L MRDL.
0.13–0.80 mg/L
Sample range · 2025. 4 mg/L MCL.
8.8 µg/L
Highest sample · 2025; range ND–8.8. 10 µg/L MCL.
13.6 µg/L
Highest locational running annual average · 2025; range 1.8–26.8. 80 µg/L MCL.
1.3 µg/L
Highest locational running annual average · 2025; range ND–2.1. 60 µg/L MCL.
This expanded summary selects useful results from the official report. Open the original PDF for every table, sampling note and notice.
Open original Tucson Water — Main System report ↗
| Substance | Reported result | Measurement basis / year | Comparison benchmark | How to read it |
|---|---|---|---|---|
| Hardness | Hard; numeric value not supplied here | Tucson Water confirms hard water in its guidance. This report does not supply a single numeric hardness value for the main system. Check the neighborhood dashboard or test your incoming water. | USGS: >180 mg/L as CaCO₃ is very hard | Hard — utility guidance |
| Chlorine | 1.0 mg/L | Reported result · 2025; range 0.94–1.07 | 4 mg/L MRDL | Below disinfectant limit |
| Fluoride | 0.13–0.80 mg/L | Sample range · 2025 | 4 mg/L MCL | Below listed limit |
| Arsenic | 8.8 µg/L | Highest sample · 2025; range ND–8.8 | 10 µg/L MCL | Below limit; 88% of benchmark |
| Total trihalomethanes | 13.6 µg/L | Highest locational running annual average · 2025; range 1.8–26.8 | 80 µg/L MCL | Below listed limit |
| Haloacetic acids | 1.3 µg/L | Highest locational running annual average · 2025; range ND–2.1 | 60 µg/L MCL | Below listed limit |
| Nitrate | 6.7 mg/L | Highest sample · 2025; range 0.25–6.7 | 10 mg/L MCL | Below listed limit |
| Barium | ND–0.15 mg/L | Sample range · 2025 | 2 mg/L MCL | Below listed limit |
| Selenium | ND–4.3 µg/L | Sample range · 2025 | 50 µg/L MCL | Below listed limit |
| Sodium | 22.4–70.4 mg/L | Sample range · 2025 | No limit listed in report | No high/low rating assigned |
mg/L ≈ ppm; µg/L ≈ ppb. ND means not detected at the method’s reporting level, not proven zero. MCL is the report’s maximum contaminant level; MRDL is its disinfectant limit. Secondary guidelines address aesthetics. Annual averages, individual samples and source ranges are different statistics. A below-limit label is not a blanket health or home-safety rating.
A locational running annual average includes the preceding four quarters and can exceed the current calendar year’s sample maximum. PFAS and lead require their own sampling and exact-model treatment checks; absence from this summary is not a nondetection.
Find my home’s system →Continue with your home details. We will not assign another utility’s measurements to your home; confirm hardness before final sizing.
Find my home’s system →Municipal results cannot identify your well’s treatment needs. Use current testing to select equipment.
Explore well-water systems →Email delivery is coming later. For now, copy the report link to share.
More about your local water
Pima County is not a single drinking-water system. The Tucson Main System figures below do not apply automatically to Corona de Tucson, Oro Valley, Marana, other utilities or private wells. Match the system name before applying any recommendation.
A ZIP lookup narrows the location; it does not test household plumbing. A current incoming-water hardness test helps size a softener. Treatment for health-related contaminants needs appropriate testing and verified reduction claims.
Hard — utility guidance
Utility figures retain their units, measurement basis and sampling years. We use the dated reports listed below, not a statewide average. Hardness categories follow USGS; they are scale classifications, not contaminant limits.
Reviewed October 29, 2026.
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