CA
CA drinking water
2,949 active community water systems serve 44,063,617 people in CA. Browse the largest utilities, see how groundwater and surface water sources are split, and dig into individual system pages for violations and lead service line status.
At a glance
- Community systems
- 2,949
- People served
- 44.1M
- Groundwater systems
- 71%
- 2,088 systems
- Surface water systems
- 29%
- 860 systems
Largest community water systems by population served
- 1. LOS ANGELES-CITY, DEPT. OF WATER & POWER
LOS ANGELES · PWSID CA1910067
7.8M served - 2. EAST BAY MUD
OAKLAND · PWSID CA0110005
1.4M served - 3. SAN DIEGO, CITY OF
SAN DIEGO · PWSID CA3710020
1.4M served - 4. SAN JOSE WATER
SAN JOSE · PWSID CA4310011
1.0M served - 5. SFPUC CITY DISTRIBUTION DIVISION
BURLINGAME · PWSID CA3810011
848k served - 6. EASTERN MUNICIPAL WD
PERRIS · PWSID CA3310009
667k served - 7. CITY OF FRESNO
FRESNO · PWSID CA1010007
546k served - 8. CITY OF SACRAMENTO MAIN
SACRAMENTO · PWSID CA3410020
528k served - 9. LONG BEACH UTILITIES DEPARTMENT
LONG BEACH · PWSID CA1910065
467k served - 10. IRVINE RANCH WATER DISTRICT
IRVINE · PWSID CA3010092
445k served
Cities with the most served population
Communities with the largest aggregate population across all community water systems based in that city. Click through for the per-city utility list.
- Los Angeles · 7.8M
- San Jose · 3.4M
- Oakland · 1.4M
- San Diego · 1.4M
- Sacramento · 1.2M
- Burlingame · 885k
- Anaheim · 790k
- Perris · 667k
- Fresno · 630k
- Long Beach · 467k
- Irvine · 448k
- Riverside · 402k
- San Bernardino · 378k
- Alhambra · 358k
- Fremont · 344k
- Covina · 336k
- Hawthorne · 321k
- Downey · 313k
- Santa Ana · 311k
- Newhall · 294k
- El Monte · 290k
- La Mesa · 278k
- Palm Desert · 275k
- Modesto · 239k
- Spring Valley · 239k
- Fontana · 238k
- Rosemead · 226k
- Stockton · 223k
- Oxnard · 213k
- Rancho Cucamonga · 212k
- Rancho Santa Margarita · 208k
- San Dimas · 203k
- Huntington Beach · 203k
- Concord · 199k
- Pasadena · 192k
- Chula Vista · 191k
- Glendale · 189k
- Corte Madera · 187k
- Santa Rosa · 186k
- Ontario · 185k
- Pomona · 182k
- Jurupa Valley · 178k
- Pleasanton · 176k
- Garden Grove · 175k
- Corona · 175k
- Escondido · 172k
- Oceanside · 171k
- Laguna Hills · 171k
- Lake Elsinore · 169k
- Hayward · 163k
- Rialto · 159k
- Sunnyvale · 158k
- Roseville · 156k
- Temecula · 147k
- Placerville · 143k
- Fullerton · 140k
- Bakersfield · 136k
- Victorville · 136k
- Rancho Cordova · 134k
- Vista · 132k
Showing the 60 largest cities by served population. 837 smaller communities also have pages on MyTapWater.us; reach them through the sitemap or via the address lookup.
Community water fluoridation in CA
State- and county-level aggregates from CDC's Water Fluoridation Reporting System. Per-utility fluoridation status is not in the bulk dataset; for a specific system, see the link below.
- Population on fluoridated water (2020)
- 57.5%
- 21,879,582 of 38,051,212 on CWS
- Community systems fluoridating
- 417 of 3,057
- 48 actively adjust fluoride
- Counties with 2020 data
- 58
- State shares per-system data on MWF
Trend over time
- 202057.5%
- 201859.3%
- 201660.6%
Highest fluoridation rate by county
- San Francisco99.5%
- San Mateo98.2%
- Alameda97.9%
- Contra Costa96.2%
- Marin95.9%
- Ventura94.6%
- Orange91.7%
- San Diego91.1%
- Solano89.3%
- Sutter75.6%
Lowest fluoridation rate by county
- Stanislaus0.0%
- El Dorado0.0%
- Santa Cruz0.0%
- Monterey0.0%
- Shasta0.0%
- Tuolumne0.0%
- Lake0.0%
- Mendocino0.0%
- Nevada0.0%
- Calaveras0.0%
Find your specific utility's status
CA shares per-system fluoridation data on CDC's My Water's Fluoride site. Search by water system to see whether a specific utility adjusts fluoride.