Is Arizona tap water hard or soft?
Yes, mostly. 92 % of the 12 cities with published data in Arizona have hard or very hard water (over 120 mg/L). The median is 13 gpg, from 7 gpg in El Mirage to 16 gpg in Fountain Hills.
We have published hardness data for 12 cities in Arizona. The median is 13 gpg; the hardest water is in Fountain Hills (16 gpg), the softest in El Mirage (7 gpg).
92 % of these cities have hard or very hard water (over 120 mg/L).
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Cities in Arizona, hardest first
| gpg | mg/L | ||
|---|---|---|---|
| Fountain Hills | 16 | 274 | very hard |
| Mesa | 16 | 274 | very hard |
| Scottsdale AZ | 14.6 | 250 | very hard |
| Phoenix | 13.8 | 237 | very hard |
| Maricopa | 13.4 | 230 | very hard |
| Tucson | 13.4 | 229 | very hard |
| Marana | 12.6 | 215 | very hard |
| Queen Creek | 12 | 206 | very hard |
| Paradise Valley | 12 | 205 | very hard |
| Oro Valley | 8.9 | 153 | hard |
| Tolleson | 8.5 | 146 | hard |
| El Mirage | 7 | 120 | moderately hard |
FAQ
Is Arizona water hard or soft?
Yes, mostly. 92 % of the 12 cities we cover have hard or very hard water; the median is 13 gpg.
Which city in Arizona has the hardest water?
Fountain Hills, at 16 gpg, has the hardest water of the 12 cities with published data.
Which city in Arizona has the softest water?
El Mirage, at 7 gpg, has the softest water of the 12 cities with published data.
Do I need a water softener in Arizona?
Above about 120 mg/L (7 gpg) scale builds up in water heaters, kettles and dishwashers, and a softener or at least regular descaling pays off. Look up your own city in the table: in Arizona the values range from 7 gpg to 16 gpg.
On a private well? Well water hardness in Arizona by county →