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.

1 to 100 of 759, by people served

California utilities whose water varies in hardness, 1 to 100
Utility	Based in	Serves	Hardness, mg/L	Grains per gallon
Los Angeles - City, Dept. of Water & Power	Los Angeles	3,875,566	94 to 544	5.5 to 31.8
East Bay MUD	Oakland	1,468,000	17 to 120	1 to 7
City of San Diego	San Diego	1,408,937	113 to 619	6.6 to 36.2
San Jose Water	San Jose	1,039,920	112 to 512	6.5 to 29.9
SFPUC City Distribution Division	Burlingame	848,019	9 to 256	0.5 to 14.9
City of Fresno	Fresno	545,970	8.8 to 390	0.5 to 22.8
City of Sacramento Main	Sacramento	527,979	15 to 320	0.9 to 18.7
Long Beach Utilities Department	Long Beach	466,772	11 to 280	0.6 to 16.4
Alameda County Water District	Fremont	344,000	40 to 138	2.3 to 8.1
City of Santa Ana	Santa Ana	316,184	125 to 395	7.3 to 23.1
City of Riverside	Riverside	302,776	55 to 395	3.2 to 23.1
Santa Clarita Valley Water Agency	Newhall	292,014	120 to 568	7 to 33.2
Helix Water District	La Mesa	277,918	130 to 353	7.6 to 20.6
Gswc - Southwest	Hawthorne	277,740	120 to 280	7 to 16.4
Coachella Vwd: Cove Community	Palm Desert	270,000	7.5 to 326	0.4 to 19.1
Cws - Bakersfield	San Jose	268,129	55 to 325	3.2 to 19
San Gabriel Valley Water Co. - El Monte	El Monte	240,000	91 to 340	5.3 to 19.9
San Gabriel Valley WC - Fontana	Fontana	228,270	90 to 234	5.3 to 13.7
City of Modesto	Modesto	218,915	35 to 388	2 to 22.7
San Bernardino City	San Bernardin0	214,665	120 to 320	7 to 18.7
Cucamonga Valley Water District	Rancho Cucuamonga	213,375	86 to 244	5 to 14.3
Contra Costa Water District	Concord	210,500	52 to 132	3 to 7.7
Los Angeles Cwwd 40 Reg 4 & 34 Lancaster	Alhambra	208,129	14 to 240	0.8 to 14
City of Huntington Beach	Huntington Beach	201,000	62 to 264	3.6 to 15.4
Sacramento Suburban Water District	Sacramento	194,444	54 to 370	3.2 to 21.6
City of Stockton	Stockton	192,702	17 to 349	1 to 20.4
SCWA - Laguna/Vineyard	Sacramento	188,417	9.1 to 385	0.5 to 22.5
Marin Municipal Water District	Corte Madera	188,116	53 to 117	3.1 to 6.8
Ontario Municipal Utilities Company	Ontario	185,010	83 to 190	4.8 to 11.1
California Water Service - Stockton	San Jose	182,775	47 to 380	2.7 to 22.2
City of Santa Rosa	Santa Rosa	178,452	92 to 198	5.4 to 11.6
City of Bakersfield	Bakersfield	171,108	3.9 to 552	0.2 to 32.3
Suburban Water Systems - San Jose	Covina	170,523	147 to 290	8.6 to 17
Elsinore Valley MWD	Lake Elsinore	169,455	11 to 580	0.6 to 33.9
City of Roseville	Roseville	165,736	18 to 250	1 to 14.6
Pasadena Water and Power	Pasadena	165,448	122 to 393	7.1 to 23
City of Hayward	Hayward	162,954	131 to 260	7.7 to 15.2
Cws - Visalia	San Jose	153,522	20 to 200	1.2 to 11.7
Pomona - City, Water Dept.	Pomona	151,713	160 to 365	9.4 to 21.3
California Water Service Co. - Dominguez	San Jose	149,490	48 to 1250	2.8 to 73.1
Rancho California Water District	Temecula	146,147	5.1 to 370	0.3 to 21.6
California Water Service Co. - Ela	San Jose	142,140	144 to 335	8.4 to 19.6
Victorville Water District	Victorville	140,721	2.7 to 210	0.2 to 12.3
City of Escondido	Escondido	137,044	150 to 255	8.8 to 14.9
Jurupa Community SD	Jurupa Valley	134,638	130 to 475	7.6 to 27.8
City of Santa Clara	Santa Clara	134,587	170 to 360	9.9 to 21.1
City of Clovis	Clovis	133,118	9 to 285	0.5 to 16.7
Palmdale Water Dist.	Palmdale	126,804	29 to 240	1.7 to 14
City of Vallejo	Vallejo	121,420	99 to 176	5.8 to 10.3
City of Orange	Orange	120,770	143 to 373	8.4 to 21.8
City of Fairfield	Fairfield	120,720	99 to 184	5.8 to 10.7
City of Antioch	Antioch	116,781	61 to 134	3.5 to 7.8
Golden State WC - West Orange County	Anaheim	114,693	57 to 360	3.3 to 21.1
Cwsc Salinas	San Jose	114,286	117 to 600	6.8 to 35.1
Downey - City, Water Dept.	Downey	110,556	135 to 368	7.9 to 21.5
Cal - Water Service Co. - Chico	San Jose	110,473	84 to 295	4.9 to 17.3
Azusa Light and Water	Azusa	110,044	100 to 290	5.8 to 17
Mesa Water District	Costa Mesa	110,000	21 to 239	1.2 to 13.9
East Valley Water District	Highland	108,600	89 to 280	5.2 to 16.4
City of Daly City	Daly City	102,593	142 to 310	8.3 to 18.1
Hesperia WD	Hesperia	101,836	5 to 132	0.3 to 7.7
City of Vacaville	Vacaville	99,650	70 to 301	4.1 to 17.6
City of Tracy	Tracy	98,215	71 to 380	4.2 to 22.2
West Valley Water District	Rialto	96,123	88 to 245	5.1 to 14.3
City of Merced	Merced	96,073	59 to 260	3.5 to 15.2
Santa Cruz Water Department	Santa Cruz	94,626	121 to 327	7.1 to 19.1
City of Westminster	Westminster	93,591	137 to 378	8 to 22.1
Placer CWA - Foothill	Auburn	93,417	13 to 93	0.8 to 5.4
City of Santa Barbara Water Department	Santa Barbara	93,334	54 to 420	3.2 to 24.6
Compton - City, Water Dept.	Compton	90,986	110 to 281	6.4 to 16.4
Santa Monica - City, Water Division	Santa Monica	90,729	148 to 760	8.7 to 44.4
City of Redding	Redding	90,254	34 to 142	2 to 8.3
City of Chino	Chino	90,187	160 to 590	9.4 to 34.5
Indio Water Authority	Indio	89,137	71 to 190	4.2 to 11.1
South Gate - City, Water Dept.	South Gate	88,544	178 to 260	10.4 to 15.2
City of Manteca	Manteca	84,928	73 to 330	4.3 to 19.3
City of Napa	Napa	84,804	30 to 159	1.8 to 9.3
City of Buena Park	Buena Park	82,667	45 to 309	2.6 to 18
Inglewood - City, Water Dept.	Inglewood	81,191	173 to 384	10.1 to 22.5
City of Alhambra	Alhambra	80,279	107 to 313	6.3 to 18.3
City of Upland	Upland	78,376	77 to 300	4.5 to 17.5
Redlands City MUD - Water Div	Redlands	78,025	85 to 225	5 to 13.2
City of Chino Hills	Chino Hills	76,314	13 to 630	0.8 to 36.8
Desert Water Agency	Palm Springs	75,588	34 to 330	2 to 19.3
City of Turlock	Turlock	72,888	64 to 152	3.7 to 8.9
City of Tulare	Tulare	72,241	3.6 to 63	0.2 to 3.7
City of Newport Beach	Newport Beach	69,520	51 to 361	3 to 21.1
Valley County Water Dist.	Baldwin Park	68,871	149 to 364	8.7 to 21.3
City of Davis	Davis	67,826	61 to 625	3.6 to 36.5
Citrus Heights Water District	Citrus Heights	67,818	99 to 165	5.8 to 9.6
City of Palo Alto	Palo Alto	67,658	89 to 350	5.2 to 20.5
City of Lodi	Lodi	67,093	15 to 330	0.9 to 19.3
Beaumont Cherry Valley WD	Beaumont	66,841	115 to 240	6.7 to 14
City of Madera	Madera	66,560	43 to 163	2.5 to 9.5
Lakewood - City, Water Dept.	Lakewood	66,356	46 to 260	2.7 to 15.2
Cwsc Los Altos Suburban	San Jose	63,559	146 to 445	8.5 to 26
City of Porterville	Porterville	63,487	70 to 190	4.1 to 11.1
Liberty Utilities (Av Ranchos) Corp.	Downey	63,381	31 to 260	1.8 to 15.2
City of Pittsburg	Pittsburg	62,500	61 to 550	3.5 to 32.2
City of Woodland	Woodland	61,462	61 to 400	3.6 to 23.4

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.

1 to 100 of 759, by people served

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