Hardest and softest tap water in the United States

All 1372 cities in the United States with published data, ranked by total hardness. The national median is 9.1 gpg.

USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.

25 cities with the hardest water

#		gpg	mg/L
1	Asheville · North Carolina	0.3	6	soft
2	Mauldin · South Carolina	0.3	6	soft
3	College Station · Texas	0.4	6	soft
4	South Portland · Maine	0.4	7	soft
5	Westbrook · Maine	0.4	7	soft
6	Fairhope · Alabama	0.4	8	soft
7	Bryan · Texas	0.5	8	soft
8	Tulare · California	0.5	8	soft
9	Ozark · Alabama	0.5	9	soft
10	Southern Pines · North Carolina	0.6	10	soft
11	Denham Springs · Louisiana	0.6	10	soft
12	Chambersburg · Pennsylvania	0.6	10	soft
13	Colfax · California	0.6	10	soft
14	Grass Valley · California	0.6	11	soft
15	Hanford · California	0.7	12	soft
16	Minden · Louisiana	0.7	12	soft
17	Taunton · Massachusetts	0.7	13	soft
18	Lynnwood · Washington	0.7	13	soft
19	McFarland · California	0.8	13	soft
20	Somerville · Massachusetts	0.8	13	soft
21	Malden · Massachusetts	0.8	13	soft
22	Boston · Massachusetts	0.8	13	soft
23	Warrens · Wisconsin	0.8	14	soft
24	Placerville · California	0.8	14	soft
25	Auburn · California	0.9	15	soft