California utilities with moderately hard water.

61 to 120 mg/L (3.6 to 7 grains per gallon). 414 utilities serving 465,877 people as they report it, largest first.

301 to 414 of 414, by people served

California utilities with moderately hard water, 301 to 414, 301 to 414
Utility	Based in	Serves	Hardness, mg/L	Grains per gallon
Leafwood Community WA	Salinas	69	63	3.7
Westside Harvesting	Fresno	69	96	5.6
Sierra Meadows	Kernville	68	62	3.6
Mineral Mountain Mutual Water	Muphys	67	64	3.7
Rau Dairy	Caruthers	66	120	7
River Ranch Farm Worker Center	Napa	66	75	4.4
Vierra Knolls MWC	Salinas	66	75	4.4
4n Mobilehome Park	Oakdale	65	110	6.4
Bianchi Flowers Inc	Pescadero	65	106	6.2
Blue Lakes Village	Santa Rosa	65	97	5.6
Delta Conservation Camp	Suisun City	65	118	6.9
Garlen Court WS	Salinas	65	84	4.9
Vierra Meadows MWC	Salinas	65	106	6.2
Country Club County WD	Turlock	64	79	4.6
Humboldt Woodlands Mutual	Forest Ranch	64	89	5.2
Lone Pine MHP	Oakdale	64	85	5
Melita Heights Mutual Water Company	Santa Rosa	64	94	5.5
Wegis Mutual Water Company	Bakersfield	64	62	3.6
Abbey of New Clairvaux	Vina	63	98	5.7
Azcal Management Co	Lemoore	63	115	6.7
Forest Point Mhc	Stockton	62	74	4.3
Lassen Mobile Home Park	Torrance	62	95	5.6
Ranchos del Rio	Bakersfield	62	68	4
Antelope Valley Mobile Estates	South Pasadena	60	71	4.2
Delany WC	Royal Oaks	60	81	4.7
Gold Country Home Park - Water System	Sacramento	60	71	4.2
Isot Community Water System	Canby	60	92	5.4
Psmcsd - Blackie Rd WS	Royal Oaks	60	102	6
Rancho Marina	Sacramento	60	105	6.1
Countryside Care Center	Fresno	56	84	4.9
Desmond Rd WS #03	Salinas	56	66	3.9
Paradise Rd WS #09	Salinas	56	66	3.9
Tully Mobile Estates	Oakdale	56	62	3.6
Cal Fire - Mountain Home Cnsrvtn Camp	Springville	55	65	3.8
Llanas Camp Four Water System	Shafter	54	82	4.8
Sequoia Water Assoc	Courtland	54	73	4.3
Little Avenue Water System	Red Bluff	53	100	5.8
Meadow Edge MHP	Vinton	53	61	3.6
Aptos Ridge Mutual Water Co	Watsonville	52	91	5.3
Agape Mutual Water System	Bakersfield	50	96	5.6
Galindo Housing Facility	Indio	50	84	4.9
Gosford Road Water Company	Bakersfield	50	71	4.2
Graton Mutual Water System	Rohnert Park	50	92	5.4
Lancaster Park Mobile Home Park	Lancaster	50	76	4.4
Midway Mobilehome Park	Ojai	50	109	6.4
Owens Peak South	Ridgecrest	50	105	6.1
Rancho Salinas Mbwc	Paso Robles	50	93	5.5
Tahoe Park Water Co - Skyland/Nielsen	Eldorado Hills	50	89	5.2
Baumann Rd WS #01	Watsonville	48	118	6.9
Kinnybrook Mutual Water Company	Kenwood	48	85	4.9
Echo Valley Rd WS #05	Salinas	45	73	4.3
Golden Acres Trailer Park	Red Bluff	45	94	5.5
Huckleberry Mutual Water Company	Cazadero	45	110	6.4
Leisure Acres Mutual Water Company	North Fork	45	120	7
Norcal Water Works	Sacramento	45	114	6.7
Olive Dell Ranch	Colton	45	120	7
Burlando Heights Mutual Water Co.	Kernville	44	72	4.2
Pine Ridge Park Estates	Red Bluff	44	101	5.9
Rio Ranch Community Svcs Dist	Red Bluff	44	62	3.6
Viking Rv Park	Kingsburg	44	75	4.4
Kranenburg Water System	Bakersfield	42	100	5.8
Paradise Rd WS #05	Prunedale	42	74	4.3
Sierra North Community Service District	Bishop	42	90	5.2
Hartley Mutual Water System	Chico	41	89	5.2
Riverside Crossing MHP	Los Molinos	41	108	6.3
Britz/Colusa	Fresno	40	100	5.8
The Village	Coarsegold	40	77	4.5
Wine Country Apartments	Stockton	40	86	5
Ali Mutual Water Co	Tulare	39	90	5.3
Heath Brimhall P.O.A.	Bakersfield	39	110	6.4
Lodi Homes	Tracy	39	65	3.8
Pappas & Co (Mendota)	Fresno	39	84	4.9
Sonoma Springs	Glen Ellen	37	80	4.7
Sunrise Mobilehome Park	San Francisco	37	85	5
148 East Water System	Inyokern	36	120	7
Spaulding Eagle Lake MWC	Susanville	36	86	5
Camp Owen Water System	Kernville	35	76	4.4
Life Water Co - Op	Inyokern	35	88	5.1
Sce Bishop Creek Plant 4	Rosemead	35	64	3.7
Two Twenty Four Mobile Home Pk	Clovis	35	120	7
Fcsa 44c - Riverview Estates	Fresno	34	63	3.7
Palomar Christian Conference Center	Palomar Mountain	33	111	6.5
Aptos Hills Mutual Water Co	Watsonville	32	93	5.4
Shastina Mobile Estates	Roseville	32	115	6.7
Rosecrest Mutual	Roseville	31	103	6
Bridgehaven Park	Sacramento	30	86	5
LADWP - Control Gorge Power Plant	Los Angeles	30	66	3.8
Mammoth Pool Mobile Home Park	Palm Springs	30	120	7
Richardson Beardsley Park Inc.	Julian	30	97	5.6
Camp Stevens	Julian	28	63	3.7
Los Angeles, City of - Power Plant #2	Saugus	28	86	5
Ymca Camp Marston/Raintree	Julian	28	103	6
Mitchell'S Avenue E Mobile Home Park	Lancaster	27	65	3.8
Pine Hill Terrace Mobile Home Park	Sebastopol	27	96	5.6
Schweikart Water System	Bakersfield	27	104	6.1
Albion Mutual Water Company	Albion	26	94	5.5
Emerald City Mutual Water Co	Aptos	26	78	4.5
Frontier Trails Homeowners Assoc Inc.	Kernville	26	117	6.8
Loch Haven Mutual Water Company	Santa Rosa	26	115	6.7
Rio Vista Mobilehome Estates	Redding	26	98	5.7
South Desert Mutual Water Company	Inyokern	26	105	6.1
Big Springs Mutual Water System	Old Station	25	63	3.7
Blue Mountain Center	Tomales	25	77	4.5
Covington Mill - A	Redding	25	108	6.3
Falling Rock Rv Park	Oroville	25	88	5.1
Jackson Hide - A - Way	Ocotillo	25	62	3.6
Van Loon Water Association	Bishop	25	97	5.6
Whispering Pines Mobile Home Park	Yuba City	25	95	5.6
Harris Feeding Company	Coalinga	22	86	5
Sierra Village Mobile Home Park	MI Wuk Village	21	85	5
Harris Farms/Horse Barn	Coalinga	20	89	5.2
Fourth Street Water System	Lake Isabella	12	120	7
Los Angeles, City of - Power Plant #1	Saugus	10	87	5.1
North Shore MWC	Fawnskin	7	68	4

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.

301 to 414 of 414, by people served

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