California Water Hardness map

California

Water Quality in the State of California

California's water is controlled by the state government. Most of the supplied water for Southern California and the Central Valley (home to half of the state's population), depends on three major projects; State Water Project, the Colorado River Aqueduct (imported water from out of state) and the Central Valley Project. California's vast agricultural industry is also dependent on these water projects, both large and small.

Groundwater is also an important part of the state’s water supplies, comprising about 40% of the water used in an average year, and 60% or more in a drought year. But groundwater is very much location-dependent: some communities have no groundwater and rely on surface water while other communities may have only groundwater. Other communities depend on a mix of imported water and groundwater, and even some rely solely on imported water. 

California Water Hardness by City

California water is considered hard to very hard. The average water hardness for California residents is 100-300 PPM. The state's most populous city and the second-most populous city in the US, Los Angeles, has a water hardness average of 127 PPM and San Francisco has a hard water level of 47 PPM. 

Who has the hardest water in the United States?

Ventura California with a water hardness or 666 PPM is the hardest water in the United States. This is among the municipal water quality reports we have documented. Ventura Water quality report 2022.

For more information on water hardness in specific cities, please see the table below.

City & Zip Codes Water Hardness Data

Anaheim

92804 | 92805 | 92801 | 92802 | 92806 | 92807 | 92808

127 PPM (mg/L) or 7 gpg

Bakersfield

93307 | 93306 | 93312 | 93309 | 93308 | 93313 | 93304 | 93311 | 93305 | 93314 | 93301

80 PPM (mg/L) or 5 gpg

Bellflower

90706 | 90707

230 PPM (mg/L) or 13 gpg

Buena Park

90620 | 90621 | 90622 | 90623 | 90624

236 PPM (mg/L) or 14 gpg

Burbank

91501 | 91502 | 91504 | 91505 | 91506

271 PPM (mg/L) or 16 gpg

Chino

91710 | 91708
188 PPM (mg/L) or 11 gpg

Chula Vista

91911 | 91910 | 91913 | 91915 | 91914

194 PPM (mg/L) or 11 gpg

Cresent City

95531

59 PPM (mg/L) or 3 gpg

Corona

92882 | 92880 | 92879 | 92883 | 92881

353 PPM (mg/L) or 21 gpg

Coachella

92236

140 PPM (mg/L) or 8 gpg

Compton

90059 | 90220 | 90221 | 90222 | 90223 | 90224

219 PPM (mg/L) or 13 gpg

El Monte

91732 | 91731
270 PPM (mg/L) or 16 gpg

Fontana

92355 | 92336 | 92337

104 PPM (mg/L) or 6 gpg

Fountain Valley

92728

199 PPM (mg/L) or 12 gpg

Fremont

94536 | 94538 | 94539 | 94555

158 PPM (mg/L) or 9 gpg

Fresno

93722 | 93727 | 93720 | 93702 | 93726 | 93706 | 93711 | 93705 | 93703 | 93710 | 93704 | 93725 | 93728 | 93723 | 93730 | 93701 | 93721 | 93650

123 PPM (mg/L) or 7 gpg

Fountain Valley

92708

200 PPM (mg/L) or 12 gpg

Fullerton

92833 | 92831 | 92832 | 92835

254 PPM (mg/L) or 15 gpg

Garden Grove

92840 | 92843 | 92841 | 92844 | 92845

119 PPM (mg/L) or 7 gpg

Gilroy

95020

236 PPM (mg/L) or 14 gpg

Glendale

91205 | 91206 | 91201 | 91202 | 91204 | 91208 | 91203 | 91207 | 91210

259 PPM (mg/L) or 15 gpg

Hemet

92544 | 92545 | 92543
192 PPM (mg/L) or 11 gpg

Huntington Beach

92647 | 92646 | 92648 | 92649

240 PPM (mg/L) or 14 gpg

Inglewood

90301 | 90302 | 90303 | 90304 | 90305 | 90306 | 90307 | 90308 | 90309 | 90311 | 90312

293 PPM (mg/L) or 17 gpg

Irvine

92620 | 92618 | 92612 | 92604 | 92614 | 92602 | 92606 | 92603 | 92617

152 PPM (mg/L) or 9 gpg

Laguna Niguel

92607 | 92653 | 92677 

273 PPM (mg/L) or 16 gpg

La Habra

90631

255 PPM (mg/L) 15 gpg

Lake Forest

92609 | 92610 | 92630 | 92679 | 92691

274 PPM (mg/L) or 16 gpg

Livermore

94550 | 94551
100 PPM (mg/L) or 6 gpg 

Long Beach

90805 | 90813 | 90806 | 90815 | 90802 | 90804 | 90808 | 90810 | 90803 | 90807 | 90814 | 90822 | 90831

137 PPM (mg/L) or 8 gpg

Los Angeles

90011 | 90044 | 90003 | 90026 | 90019 | 90022 | 90037 | 90042 | 90006 | 90004 | 90066 | 90001 | 90034 | 90018 | 90002 | 90063 | 90046 | 90024 | 90057 | 90047 | 90025 | 90065 | 90032 | 90033 | 90023 | 90016 | 90059 | 90027 | 90043 | 90007 | 90045 | 90005 | 90020 | 90031 | 90036 | 90029 | 90049 | 90012 | 90062 | 90008 | 90028 | 90039 | 90041 | 90035 | 90038 | 90061 | 90017 | 90064 | 90048 | 90015 | 90068 | 90040 | 90013 | 90077 | 90014 | 90056 | 90089 | 90010 | 90021 | 90058 | 90067 | 90073 | 90071 | 90079 | 90095

127 PPM (mg/L) or 7 gpg

Lynwood

90262

262 PPM (mg/L) or 15 gpg

Mecca

92254

393 PPM (mg/L) or 23 gpg

Menifee

92584 | 92585 | 92586 | 92587

93 PPM (mg/L) or 5 gpg

Mendocino

95460

101 PPM (mg/L) or 5 gpg

Mission Viejo

92653 | 92690 | 92691 | 92692

274 PPM (mg/L) or 16 gpg

Modesto

95355 | 95350| 95351 | 95358 | 95356 | 95354 | 95357

224 PPM (mg/L) or 13 gpg

Newport Beach

92603 | 92617 | 92625 | 92651 | 92657 | 92658 | 92659 | 92660 | 92661 | 92662 | 92663

274 PPM (mg/L) or 16 gpg

Norwalk

90650 | 90651 | 90652 | 90670

267 PPM (mg/L) or 16 gpg

Oakland

94601 | 94602 | 94603 | 94605 | 94606 | 94607 | 94609 | 94610 | 94611 | 94612 | 94613 | 94618 | 94619 | 94621

140 PPM (mg/L) or 8 gpg

Oceanside

92057 | 92056 | 92058 | 92054

168 PPM (mg/L) or 10 gpg

Orange

92867 | 92869 | 92868 | 92865 | 92866

108 PPM (mg/L) or 6 gpg

Oxnard

93033 | 93030 | 93036 | 93035

285 PPM (mg/L) or 17 gpg

Pasadena

91104 | 91107 | 91103 | 91106 | 91101 | 91105

255 PPM (mg/L) or 15 gpg

Pico Rivera

90660

241 PPM (mg/L) or 14 gpg

Rancho Santa Margarita

92679 | 92688 | 92692 

274 PPM (mg/L) or 16 gpg

Redding

96003 | 96001 | 96002 | 96049

31 PPM (mg/L) or 2 gpg

Redondo Beach

90277 | 90278

370 PPM (mg/L) or 22 gpg

Riveside

92503 | 92504 | 92507 | 92505 | 92506 | 92508 | 92501

71 PPM (mg/L) or 4 gpg

Roseville

95661 | 95678 | 95747

191 PPM (mg/L) 11 gpg

Sacramento

95823 | 95828 | 95822 | 95831 | 95833 | 95835 | 95838 | 95826 | 95825 | 95820 | 95821 | 95842 | 95824 | 95834 | 95829 | 95815 | 95864 | 95818 | 95827 | 95841 | 95819 | 95816 | 95817 | 95832 | 95814 | 95811 | 95830 | 95837 | 94574

150 PPM (mg/L) or 9 gpg

Salinas

93906 | 93905 | 93901 | 93907 | 93908

160 PPM (mg/L) or 9 gpg

San Bernardino

92407 | 92404 | 92410 | 92405 | 92411 | 92408 | 92401

249 PPM (mg/L) 15 gpg

San Clemente

92672 | 92673 | 92674

274 PPM (mg/L) or 16 gpg

San Diego

92154 | 92126 | 92105 | 92114 | 92115 | 92117 | 92113 | 92130 | 92129 | 92128 | 92111 | 92127 | 92122 | 92109 | 92104 | 92102 | 92101 | 92139 | 92103 | 92131 | 92116 | 92124 | 92123 | 92107 | 92110 | 92120 | 92119 | 92108 | 92106 | 92121 | 92140 | 92145 | 92135 | 92147 | 92155 | 92134 | 92132

241 PPM (mg/L) or 15 gpg

San Francisco

94112 | 94110 | 94122 | 94109 | 94116 | 94117 | 94121 | 94134 | 94118 | 94124 | 94115 | 94114 | 94132 | 94102 | 94131 | 94107 | 94103 | 94133 | 94123 | 94127 | 94108 | 94105 | 94158 | 94129 | 94111 | 94130 | 94104 | 94128

47 PPM (mg/L) or 3 gpg

San Jose

95123 | 95127 | 95111 | 95112 | 95122 | 95116 | 95125 | 95124 | 95148 | 95136 | 95132 | 95129 | 95121 | 95120 | 95128 | 95126 | 95118 | 95131 | 95117 | 95133 | 95134 | 95135 | 95138 | 95110 | 95130 | 95119 | 95139 | 95113

 132 PPM (mg/L) or 8 gpg

Santa Barbara

93101 | 93105 | 93103 | 93111 | 93110 | 93109 | 93108

391 PPM (mg/L) or 23 gpg

Santa Clarita

91350 | 91390
271 PPM (mg/L) or 16 gpg

Santa Maria

93453 | 93458 | 93455 | 93454

235 PPM (mg/L) or 14 gpg

Santa Monica

90405 | 90403 | 90404 | 90402 | 90401

114 PPM (mg/L) or 7 gpg

Stockton

95206 | 95207 | 95209 | 95210 | 95205 | 95219 | 95204 | 95212 | 95215 | 95203 | 95202 | 95211

194 PPM (mg/L) or 14 gpg

Sunnyvale

94087 | 94086 | 94085 | 94089

300 PPM (mg/L) or 17 gpg

Temecula

92592 | 92591 | 92590

152 PPM (mg/L) or 9 gpg

Torrance

90248 | 90277 | 90278 | 90501 | 90503 | 90504 | 90505 | 90506 | 90507 | 90508 | 90509 | 90510

427 PPM (mg/L) or 25 gpg

Tracy

95376 | 95377 | 95391 | 95304
143 PPM (mg/L) or 8 gpg

Turlock

95380 | 95382

115 PPM (mg/L) or  7 gpg

Tustin

92780 | 92782

 

312 PPM (mg/L) or 18 gpg

Union City

94587

89 PPM (mg/L) or 5 gpg

Upland

91784 | 91786

150 PPM (mg/L) or 9 gpg
 

Vacaville

95687 | 95688

183 PPM (mg/L) or 11 gpg
 

Valencia

91354 | 91355
268 PPM (mg/L) or 16 gpg
 

Vallejo

94589 | 94590 | 94591

129 PPM (mg/L) or 8 gpg
 

Ventura

93001 | 93003 | 93004
666 PPM (mg/L) or 39 gpg
 

Victorville

92392 | 92394 | 92395

31 PPM (mg/L) or 2 gpg
 

Visalia

93277 | 93291 | 93292

81 PPM (mg/L) or 5 gpg
 

Vista

92081 | 92083 | 92084

161 PPM (mg/L) or 9 gpg
 

Walnut Creek

94595 | 94596 |  94597 |  94598

78 PPM (mg/L) or 5 gpg

Watsonville

95076

252 PPM (mg/L) or 15 gpg
 

West Corvina

91790 | 91791
150 PPM (mg/L) or 9 gpg
 

West Sacramento

95605 | 95691

65 PPM (mg/L) or 4 gpg

Westminster

92683

239 PPM (mg/L) or 14 gpg

Whittier

90601 | 90602 |  90603 | 90604 | 90605 | 90606
260 PPM (mg/L) or 15 gpg

Woodland

95695 | 95776
63 PPM (mg/L) or 4 gpg
 

Yorba Linda

92808 | 92885 | 92886 | 92887

274 PPM (mg/L) or 16 gpg
 

Yuba City

95991 | 95993
58 PPM (mg/L) or 3 gpg
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PPM = Parts Per Million

mg/L = Milligrams Per Liter

gpg = Grains Per Gallon

Agriculture and Water Hardness

California has the largest economy in the United States, and as a sovereign State, California would rank as the world’s 5th largest economy. In 2018, California brought in $3 trillion in Gross State Product. Top industries include Business services, Government, Finance, Manufacturing, Media and Agriculture. California is the nation’s top agriculture producing state. Not only does California supply the majority of United States agricultural products, but it is also a top contender for international agriculture exports as well. Top California crops are dairy ($6.6 billion annual), grapes ($5.8 billion annual) and almonds ($5.6 billion annual).

As the majority of California has water rich in calcium (the primary source of water hardness), many farms and food processing plants experience issues related to scale buildup in their irrigators, production, and mechanical equipment, due to the mass quantities of water flow every day. In addition, contaminants polluting soil and waterways have increased greatly over the past few decades and there is a greater need for waste and chemical control. Many farmers are looking for eco-friendly solutions that can increase the quality and yield of their crops while saving water. Read more about how HydroFLOW can increase crop yield.

Solutions to your Water Quality Problems

Fixing your water quality issues in the state of California will depend on your specific water source. It is best to test your potable water supply in order to get a better understanding of your water quality. Testing is relatively cheap. The test results will allow you to understand if your potable water has issues that need to be addressed. Common solutions to water contamination problems may include a water filtration system, a reverse osmosis system or other whole home water treatment solutions.

A problem that almost all California residents will have to deal with is hard water. One old-fashioned, inefficient, expensive and unhealthy method to treat hard water is with a salt-based water softener. Most people don’t realize that if you’re using a water softener you are basically removing calcium and magnesium from your drinking water and adding salt to your diet. In addition, many states are banning the use of salt-based water softeners

Alternative water treatment solutions such as “water conditioners” have been gaining popularity in recent years because they are cheap to operate and the best eco-friendly solution for hard water. Hydropath technology, which powers the HydroFLOW water conditioners is by far the most efficient and cost-effective eco-friendly solution to deal with hard water problems. To learn more about how HydroFLOW solves the problems created by hard water, please check out our technology page. You might want to read this blog that explains the difference between water conditioners and water softeners: Water Conditioner vs. Water Softener Blog.