Life in the desert can be harsh. With average summer highs exceeding 100 degrees F in Phoenix, AZ, staying hydrated is vital. Of course, this means you need uninterrupted access to clean, safe drinking water. This begs the question—what’s really in Phoenix tap water?

The City of Phoenix’s 2024 Water Quality Report reveals what contaminants are present. The Environmental Protection Agency (EPA), which regulates drinking water quality nationwide, has established several safety standards that potable water must meet to be deemed safe for public consumption. The water in Phoenix meets these standards. However, plenty of Arizona homeowners complain of drinking water issues, largely due to the following Phoenix water contaminants:

  • Chlorite: This disinfection byproduct (DBP) is caused by adding chlorine dioxide to the drinking water. Excessive consumption can cause nausea, vomiting, and diarrhea. The EPA’s Maximum Contaminant Level Goal (MCLG) is 0.8 parts per million (ppm). The sample results show that Phoenix’s water contained up to 0.6 ppm of chlorite in 2024.
  • Trihalomethanes: THMs are another type of disinfection byproduct and can increase the risk of bladder cancer. The Maximum Contaminant Level (MCL) allowed in drinking water is 80 parts per billion (ppb). The highest reading of THMs in Phoenix water in 2024 was 59 ppb.
  • Arsenic: High arsenic levels are linked to skin damage, circulatory problems, and cancer. The EPA continues to research the health effects of low arsenic exposure. The 2024 Water Quality Report shows a sample range of up to 8.3 ppb. The MCLG is 0 ppb, meaning no level of arsenic is considered safe.
  • Nitrate: Nitrate is most harmful to newborns because it can cause infant methemoglobinemia, also known as blue baby syndrome. Older adults may also experience increased health risks when exposed to high nitrate levels. The MCLG for nitrate is 10 ppm. Water quality testing revealed nitrate levels up to 8.2 ppm.
  • Algae: Algae blooms in the Salt River Project canals during the late summer and fall are a major source of musty-smelling water in the Phoenix area. Even though the treatment process removes algae, a strong odor may linger all the way to the tap.
  • Total dissolved solids: Sodium, sulfates, barium, cadmium, copper, fluoride, and other solids may dissolve in your drinking water. Water with a moderate-to-high amount of TDS may taste bitter, salty, or metallic. The EPA’s recommended TDS level is 500 ppm or less, but this is a secondary, non-enforceable guideline. In 2024, Phoenix tap water measured 560 to 686 ppm. When TDS levels exceed 1000 ppm, the water is considered unfit for human consumption.
  • Dissolved minerals: Water hardness is determined by the amount of dissolved calcium and magnesium. Water is considered “hard” at 7.0 to 10.5 grains per gallon (gpg). Anything over 10.5 gpg is “very hard.” Phoenix’s drinking water has a total hardness of 9.2 to 20.1 gpg. These numbers are off the charts, meaning Phoenix water is among the hardest in the country!

While the City of Phoenix adheres to all EPA safety regulations, it may not meet the standards you’ve set for your family’s drinking water quality. Aqua Science offers several solutions to address your concerns, including water conditioners, water softeners, and reverse osmosis systems. If you’re not sure where to start, contact us today to schedule water testing services at your Phoenix home.