Scottsdale Water Contaminants 2026
What contaminants have been found in Scottsdale water?
Scottsdale Water consistently meets every federal Safe Drinking Water Act standard — but "legal" and "clean" aren't the same thing. The city's annual Water Quality Report (Consumer Confidence Report) and independent testing by groups like the Environmental Working Group (EWG) regularly detect contaminants at levels above health-based guidelines, even when they're below EPA legal limits.
Here's what's actually been found in Scottsdale tap water in recent years, and what each one means for your home.
1. PFAS ("forever chemicals")
Per- and polyfluoroalkyl substances have been detected in Scottsdale's CAP-sourced water at trace levels. The EPA finalized enforceable PFAS limits in 2024 (4 parts per trillion for PFOA and PFOS), and Scottsdale is investing in advanced treatment to comply. Reverse osmosis and certified activated-carbon block filters remove the vast majority of PFAS at the tap.
2. Chromium-6 (hexavalent chromium)
The "Erin Brockovich" contaminant. EWG testing has flagged chromium-6 in Scottsdale water at levels above California's public health goal of 0.02 ppb. There is no federal limit yet. Reverse osmosis removes it effectively.
3. Arsenic
Naturally occurring in Arizona groundwater and the Colorado River. Scottsdale's reported levels are well below the EPA limit of 10 ppb, but EWG's health guideline is far stricter (0.004 ppb). RO systems and certain ion-exchange filters reduce it.
4. Disinfection byproducts: TTHMs and HAA5
When chlorine reacts with organic matter in source water, it forms trihalomethanes (TTHMs) and haloacetic acids (HAA5) — long-term cancer-risk concerns. These are routinely detected in Scottsdale tap water below federal limits but above EWG guidelines. Activated carbon filtration (whole-home or under-sink) is the most effective fix.
5. Nitrates
From agricultural runoff and septic systems, common in groundwater across the Valley. Levels in Scottsdale are well below the 10 ppm EPA limit. RO systems and anion-exchange filters handle nitrates.
6. Radium and uranium
Naturally occurring radionuclides found at very low levels in groundwater portions of Scottsdale's supply. Reported levels are well below EPA limits. RO and specialized ion-exchange resins remove them.
7. Lead
Scottsdale's source water is essentially lead-free, but lead can leach from older home plumbing, brass fittings, and pre-1986 solder. The city tests at the tap and reports compliance with the EPA Lead and Copper Rule. RO at the kitchen tap and replacing pre-1986 fixtures are the best defenses.
8. Hardness (calcium and magnesium)
Not a health hazard, but Scottsdale water averages 12–17 grains per gallon — among the hardest in the U.S. It destroys water heaters, clogs fixtures, and leaves spots on everything. A whole-home water softener is the only real fix.
9. Microplastics
Detected in tap water nationwide, including the Phoenix metro. Reverse osmosis and certified ultrafiltration (≤0.1 micron) effectively remove them.
What this means for your home
For most Scottsdale homes the most protective, cost-effective combination is:
- Under-sink reverse osmosis for drinking, cooking, and ice (handles PFAS, chromium-6, arsenic, lead, nitrates, microplastics)
- Whole-home activated carbon (handles chlorine, TTHMs, HAA5)
- Whole-home water softener (handles hardness, protects appliances)
Want to know what's in your water?
Dominick Plumbing offers a free in-home water test that measures hardness, chlorine, TDS, and pH, then walks you through targeted filtration options — no high-pressure sales.
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Licensed in Arizona (ROC #350819). Call (623) 323-4538 to schedule your free water test.