California utilities whose water varies in hardness.

Water in more than one band, depending on where or when it was sampled: each is given as its range, softest to hardest. 759 utilities serving 28 million people as they report it, largest first.

701 to 759 of 759, by people served

California utilities whose water varies in hardness, 701 to 759, 701 to 759
Utility	Based in	Serves	Hardness, mg/L	Grains per gallon
Manzanita Hills WA	Royal Oaks	75	85 to 121	5 to 7.1
Town & Country Water Company	Bakersfield	73	9.4 to 760	0.5 to 44.4
Post Ranch Inn WS	Big Sur	70	138 to 291	8.1 to 17
Westport County Water District	Westport	70	69 to 135	4 to 7.9
La Tierra Heights Mutual	Angwin	67	17 to 64	1 to 3.7
Morningside Mobilehome Park	Modesto	67	82 to 150	4.8 to 8.8
Moro Cojo Mwa	Prunedale	67	91 to 181	5.3 to 10.6
Moraga Heights Mutual Water	Canyon	66	98 to 487	5.7 to 28.5
Santa Rita Water	Lompoc	66	140 to 205	8.2 to 12
Rite of Passage/Sierra Ridge	San Andreas	65	21 to 226	1.2 to 13.2
Anza Vineyard Estates Mutual Water Co	Pismo Beach	60	61 to 240	3.5 to 14
Boulevard Heights Mutual Water	Petaluma	60	160 to 210	9.4 to 12.3
Cathedral Wood Mutual Water Company	Scotts Valley	60	168 to 325	9.8 to 19
Elkhorn Rd WS #04	Watsonville	60	89 to 227	5.2 to 13.3
Lake Francis Mutual Water Company	Dobbins	60	120 to 188	7 to 11
Terrace View Water System	Rohnert Park	60	160 to 240	9.4 to 14
Los Ranchos de Uvas Water Company	Gilroy	58	86 to 340	5 to 19.9
Hart Flat Bear Mutual Water	Bakersfield	56	165 to 280	9.6 to 16.4
Redwood Terrace Mutual	La Honda	56	39 to 420	2.3 to 24.6
R - Wild Horse Ranch	Platina	55	88 to 178	5.1 to 10.4
Walking M Ranches	Solvang	54	25 to 310	1.5 to 18.1
Green Acres Mutual Water	Morgan Hill	53	100 to 165	5.8 to 9.6
Cal Fire - Miramonte Conservation Camp	Miramonte	52	111 to 120	6.5 to 7
The Anne Sippi Clinic - Riverside Ranch	Bakersfield	51	88 to 325	5.1 to 19
B&G Mobile Home Park LLC WS	Livermore	50	86 to 197	5 to 11.5
Cascadel Mutual Water System	North Fork	50	20 to 94	1.1 to 5.5
Hunter'S Fishing Resort	Millbrae	50	39 to 127	2.3 to 7.4
Seafair Road and Water Company	Mendocino	50	48 to 82	2.8 to 4.8
Fcsa 34b - Ventana Hills	Fresno	48	160 to 300	9.4 to 17.5
Alliance Redwoods Conference Grounds	Occidental	46	120 to 170	7 to 9.9
Freeport Marina	Sacramento	45	51 to 84	3 to 4.9
Gold Rock Ranch	Winterhaven	45	150 to 280	8.8 to 16.4
Woodson Bridge Rv Park	Corning	45	47 to 107	2.7 to 6.3
Bucktail Mutual Water Company	Napa	42	143 to 198	8.4 to 11.6
Meadowridge Mutual Water Co	Freedom	42	180 to 250	10.5 to 14.6
Puerta la Cruz Cc #14	Warner Springs	40	9.9 to 140	0.6 to 8.2
Sutter Pines MHP	Sutter Creek	40	3.4 to 229	0.2 to 13.4
Santa Anita Mutual Water Company	Gaviota	38	175 to 423	10.2 to 24.7
Whispering Pines MHP	Oakhurst	38	108 to 134	6.3 to 7.8
Hungry Gulch MWC	Lake Isabella	36	95 to 140	5.6 to 8.2
Point of View Mutual Water Co	Mendocino	36	37 to 160	2.2 to 9.4
Odiyan Buddhist Retreat Center	Cazadero	35	84 to 310	4.9 to 18.1
Meadows of the Kern Mutual Water Company	Bakersfield	32	91 to 260	5.3 to 15.2
Tut Brothers Farm #96	Watsonville	32	170 to 190	9.9 to 11.1
Redwood Glen Camp & Conference Ctr	Loma Mar	31	159 to 267	9.3 to 15.6
Covelo Mobile Home Park	Ukiah	30	116 to 125	6.8 to 7.3
Krotona Institute	Ojai	30	177 to 231	10.4 to 13.5
Sierra Bella Mutual Water Company	Wofford Heights	30	78 to 140	4.6 to 8.2
Cedar Lodge	Watsonville	28	39 to 195	2.3 to 11.4
Monte Vista Christian School	Watsonville	25	180 to 192	10.5 to 11.2
Rolling Oaks Road Association	Rohnert Park	25	120 to 145	7 to 8.5
Yulica	Nevada City	25	114 to 170	6.7 to 9.9
Snug Harbor Rv Lp	Walnut Grove	24	43 to 304	2.5 to 17.8
Shady Oaks Mobile Home Park LLC	Fresno	23	94 to 170	5.5 to 9.9
Alta Sierra Mutual Water Co.	Wofford Heights	22	90 to 130	5.2 to 7.6
Palomar Observatory	Palomar Mountain	20	88 to 152	5.1 to 8.9
Indian Oaks Trailer Park	Murrieta	5	130 to 430	7.6 to 25.1
Travis AFB WTP - Vallejo	Vallejo	3	80 to 179	4.7 to 10.5
Randall - Bold Water Treatment Plant	Concord	1	61 to 134	3.5 to 7.8

Source: California State Water Resources Control Board, Division of Drinking Water, 2,449 utilities, results from Jan. 2, 2019 to July 14, 2026, read Oct. 10, 2026. Each sampling point is taken at its median; a figure is typical where every point falls in one band.

Also: 7 utilities’ own water quality reports, read by hand, each named on the utility’s page.

Bands are the U.S. Geological Survey’s, at 17.1 mg/L to the grain. People served is what each utility reports; where one sells water to another, the same people can be counted twice. How hardness is measured here.

701 to 759 of 759, by people served

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