About this site
The Phoenix Hard Water Guide helps Valley homeowners choose, size and set a water softener using their own city's published water figures.
We are independent
We don’t make, sell or install water softeners, reverse osmosis systems or whole-house filters. No manufacturer, dealer or installer pays to be listed, ranked or mentioned, and none supplies the hardness figures we use.
Where the numbers come from
Every hardness figure on this site comes from a public water authority: its yearly water quality report, a hardness fact sheet, a questions-and-answers page or its own map data. We name the authority wherever we use a figure and link to its website. The small “i” button next to each result describes the authority and the data: what kind of document it is, the data year, what was measured, how it was sampled, where the water comes from and when we last checked it against the original. The full list is on How we get our data.
How the site pays for itself
The site is paid for by advertising. Later, some product links may earn a commission from the retailer. That never changes which models we list or how we rank them: models are compared on manufacturer specifications only.
Corrections
If a figure looks wrong for your street or your water utility has published a newer report, tell us and we will check it against the source.
Where to start
If you’re new here, the Phoenix water hardness table shows every city we cover, the water softener size chart turns your city’s figure into a size, and the hardness setting by city gives the number to enter on your softener.