Monterey County, California — public water systems
At a glance
307 active public water systems are filed under Monterey County, California in EPA's SDWIS records, together reporting 476,419 people served. The largest is Cwsc Salinas, which reports serving 123,679 people. 155 are community water systems serving people where they live; the other 152 are non-community systems, such as schools, workplaces, campgrounds and gas stations with their own supply.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
307
Population served
476.4K
Community systems
155
Groundwater share
96.1%
How does Monterey County compare with other California counties?
Monterey County has the 4th-most active public water systems among the 201 counties listed for active California systems in EPA records; among the 72 with 3 or more systems, the median has 73. Its systems report 476,419 people served in total, the 19th-largest county figure in the state and 1.1% of the statewide total. The average system here reports serving 1,552 people, well below the California average of 5,706. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.
Where does Monterey County's drinking water come from?
By primary water source, Monterey County's active systems draw on groundwater (271, 88%), groundwater under influence of surface water (21, 6.8%), surface water (12, 3.9%) and purchased groundwater (3, 1%). Overall, 96% rely mainly on groundwater (including purchased groundwater) and 3.9% on surface water, compared with 85% and 15% across California. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Cwsc Salinas, draws primarily on groundwater.
What kinds of water systems operate in Monterey County?
Monterey County's active systems break down as 155 community systems (50%), 87 non-transient non-community systems (28%) and 65 transient non-community systems (21%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. EPA lists their owner types as private (87%), local government (9.1%), state government (3.3%) and federal government (1%).
The 50 largest water systems in Monterey County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Cwsc Salinas | Monterey | 123,679 | Community | Groundwater |
| 2 | Cal Am Water Company - Monterey | Monterey | 92,450 | Community | Groundwater under influence of surface water |
| 3 | Alco Water Service | Monterey | 56,253 | Community | Groundwater |
| 4 | Marina Coast Water District | Monterey | 38,377 | Community | Groundwater |
| 5 | Soledad, City of | Monterey | 19,455 | Community | Groundwater |
| 6 | Greenfield, City of | Monterey | 18,967 | Community | Groundwater |
| 7 | Cwsc King City | Monterey | 16,334 | Community | Groundwater |
| 8 | Gonzales, City of | Monterey | 8,327 | Community | Groundwater |
| 9 | Castroville Community Services District | Monterey | 7,515 | Community | Groundwater |
| 10 | Psmcsd - Pajaro | Monterey | 6,500 | Community | Groundwater |
| 11 | Soledad Mission Ws | Monterey | 6,000 | Transient non-community | Groundwater |
| 12 | Cwsc Salinas Hills | Monterey | 5,293 | Community | Groundwater |
| 13 | Correctional Training Facility - Soledad | Monterey | 4,269 | Community | Groundwater |
| 14 | Cwsc Oak Hills | Monterey | 3,161 | Community | Groundwater |
| 15 | Salinas Valley State Prison | Monterey | 2,930 | Community | Groundwater |
| 16 | Seaside Municipal Water System | Monterey | 2,800 | Community | Groundwater |
| 17 | Fort Hunter Liggett | Monterey | 2,753 | Community | Groundwater |
| 18 | Caltrans Camp Roberts Rsra Sb | Monterey | 2,560 | Transient non-community | Groundwater |
| 19 | Little Bear Water Company | Monterey | 2,327 | Community | Groundwater |
| 20 | Cwsc Las Lomas | Monterey | 2,084 | Community | Groundwater |
| 21 | Prunetree Shopping Center Ws | Monterey | 2,000 | Non-transient non-community | Groundwater |
| 22 | Tasco Spreckels Water Company | Monterey | 1,772 | Community | Groundwater |
| 23 | Caltrans Camp Roberts Rsra Nb | Monterey | 1,750 | Transient non-community | Groundwater |
| 24 | Prunedale Shopping Center Ws | Monterey | 1,650 | Non-transient non-community | Groundwater |
| 25 | Laguna Seca Recreation Ws | Monterey | 1,248 | Non-transient non-community | Groundwater |
| 26 | Cal Am Water Company - Chualar | Monterey | 1,139 | Community | Groundwater |
| 27 | Cal Am Water Company - Hidden Hills | Monterey | 1,106 | Community | Groundwater |
| 28 | Cal Am Water Company - Toro | Monterey | 1,065 | Community | Groundwater |
| 29 | Csp-Andrew Molera State Reserve | Monterey | 1,005 | Transient non-community | Groundwater under influence of surface water |
| 30 | San Antonio Lake Park North Ws | Monterey | 1,002 | Transient non-community | Groundwater |
| 31 | Cal Am Water Company - Ambler Park | Monterey | 980 | Community | Groundwater |
| 32 | Santa Lucia Preserve Ws | Monterey | 966 | Community | Groundwater |
| 33 | Psmcsd - Normco | Monterey | 928 | Community | Groundwater |
| 34 | Bud Antle, LLC-Soledad Facility Ws | Monterey | 900 | Non-transient non-community | Groundwater |
| 35 | Psmcsd - Sunny Mesa | Monterey | 880 | Community | Groundwater |
| 36 | Csp-J.P. Burns Park | Monterey | 802 | Transient non-community | Groundwater |
| 37 | Corral De Tierra Country Club Ws | Monterey | 705 | Non-transient non-community | Groundwater |
| 38 | Elkhorn School Ws | Monterey | 694 | Non-transient non-community | Groundwater |
| 39 | El Camino Real Ws #16 | Monterey | 679 | Transient non-community | Groundwater |
| 40 | Prunedale School Ws | Monterey | 655 | Non-transient non-community | Groundwater |
| 41 | San Antonio Lake Park South Ws | Monterey | 653 | Transient non-community | Surface water |
| 42 | Cdfw Elkhorn Slough Ecological Reserve | Monterey | 650 | Transient non-community | Groundwater |
| 43 | Nepenthe Ws | Monterey | 618 | Community | Surface water |
| 44 | Csp-Pfeiffer Big Sur | Monterey | 585 | Community | Groundwater |
| 45 | Carmel Riviera Mwc | Monterey | 584 | Community | Surface water |
| 46 | Echo Valley School Ws | Monterey | 579 | Non-transient non-community | Groundwater |
| 47 | San Ardo Wd | Monterey | 575 | Community | Groundwater |
| 48 | Monterey Mushrooms - Maher Crt | Monterey | 554 | Non-transient non-community | Groundwater |
| 49 | Gabilan Wc | Monterey | 535 | Community | Groundwater |
| 50 | Psmcsd - Moss Landing Harbor Ws | Monterey | 520 | Community | Groundwater |
All other water systems in Monterey County (257)
The remaining active systems filed under Monterey County, largest first, with the population each reports serving.
- Cabana Holiday Ws506
- Plaskett Creek Campgrounds Ws501
- Growers Service Assn Ws (Ice)500
- Arroyo Seco Rec Ws500
- Cypress Center Ws440
- Psmcsd - Vega Rd Ws #01438
- Post Ranch Inn Ws416
- Chamisal Wa396
- Camp Roberts - California National Guard385
- Wildhorse Cafe Ws367
- Hitchcock Rd Ws #01360
- Canada Woods Wc356
- San Lucas County Water District315
- Manzanita Park Ws309
- San Antonio School District Ws300
- Old Natividad Rd Ws #01300
- D'Arrigo Harris Rd Ws #10284
- Prunedale Mwc277
- Pedrazzi Mwc273
- Moss Landing Mwc260
- Pheneger Creek Ws256
- Royal Oaks Park Ws251
- Washington School Ws250
- Altman Plants Ws #04 -Esp 420 (Prev Cs1)250
- San Jerardo Coop Ws249
- Esalen Institute Ws246
- Monterey Dunes Mwa243
- Countryside Estates Mwc243
- Ripplewood Resort Ws220
- Pond-Derosa Oaks Wc216
- Holman Ranch Ws215
- Paradise Lake Mutual Water Co.213
- Moro Rd Ws #09210
- Big Sur Campground Ws209
- Cypress Community Church Ws207
- Paradise Rd Ws #09206
- Gonzales Gas Station Ws204
- Csp-Limekiln202
- Psmcsd - Springfield Ws200
- Colonial Oak Wc Inc.198
- Ventana Big Sur Inn Ws193
- Rolling Hills Rancho Wa185
- Fernwood Ws184
- Foothill Estates Ws183
- Struve Rd Ws #02166
- Matsui Nursery Ws165
- Psmcsd - Vierra Estates Ws164
- Carmel By the River Rv Park Ws164
- Laguna Seca Wc162
- Merrill Gardens Iris Canyon Ws161
- Esperanza Rd Ws160
- Firestone Business Park Ws154
- Bud Antle, LLC- Marina Facility Ws151
- California Orchard Ws150
- Tassajara Springs Ws150
- Spca Ws135
- El Camino Wc Inc.133
- Arroyo Center Wc130
- Coastlands Mws (Post Creek)129
- Camphora Apartments126
- Princes Camp Resort Ws126
- Assisi Mwc126
- Clear Ridge Wa123
- Pesante Rd Ws #02120
- Bluffs Ws120
- Dolan Rd Mwc120
- Big Sur Bazaar Ws119
- Hidden Canyon Ranch Mwc116
- Altman Plants Ws #03 - Espinosa 303110
- Valley Oaks MHP Ws108
- Holly Hills Mwc108
- Scheid Vineyard Ws105
- Oak Heights W & R Co Inc.105
- Asoleado Mwc101
- Hitchcock Rd Ws #02100
- Mission School Ws100
- Bradley Union School Ws100
- San Miguel Ws #01100
- Rancho Borromeo Mwc100
- Riverside Campground Ws100
- Watsonville Produce Inc.98
- Flrish Farms Ws97
- Cal Am Water Company - Ralph Lane96
- San Clemente Rancho Ws96
- Captain Cooper School Ws95
- Summerhill MHP Ws95
- Lomas Del Sol Mws93
- San Miguel Ws #2293
- Robley Property Mws92
- Oak Manor Ws92
- Mccoy Rd Ws #0592
- Vista Del Toro Ws92
- Encinal Rd Ws #0191
- Mesa Del Toro Mwc90
- Prunedale Plaza Ws90
- Tularcitos Mwc90
- Hidden Valley Wa87
- Iverson & Jacks Apts Ws86
- Driscoll Strawberry Ws85
- Lake San Antonio MHP Ws84
- Floricultura Pacific Ws82
- Jacks Ranch-Reservation Road Ws82
- Psmcsd - Langley/Valle Pacifico Ws81
- Pajaro Valley Greenhouse Ws80
- Free Will Baptist Church Ws80
- Aera Energy LLC Ws79
- Blackie Rd Ws #0578
- Strawberry Rd Ws #0678
- Manzanita Hills Wa75
- Apple Ave Ws #0275
- Harbor View Wa75
- Carmel Valley Tennis Camp Ws73
- Monterey One Water73
- Woodside Wa73
- Glenn Ave Ws #0173
- Foster Rd Ws #0272
- Alvarez Brothers Ws70
- Golden State Vintners Ws70
- Estancia Winery Ws70
- Los Carneros Mwa70
- Arroyo Seco Estates Mws70
- Loma Vista Inn Ws70
- Central Bay High School Ws70
- Hartnell Rd Ws #169
- Rod Mclellan Botanicals Ws69
- San Vicente Mwc69
- Calvary Church Inc. Ws68
- Moro Cojo Mwa67
- Vierra Knolls Mwc66
- Stonepine Resort Ws66
- Murphy Hill Ws #0266
- Vierra Meadows Mwc65
- Murphy Hill Ws #0165
- Garlen Court Ws65
- Capurro & Son Ws65
- Hidden Views MHP Ws65
- River Rd Ws #2565
- Pioneer Place Mws64
- Leafwood Community Wa64
- Z Ranch Mwc62
- Monterey Bay Nursery Ws61
- Misionero Vegetables Ws61
- Elkhorn Rd Ws #0460
- North Shore Estates Ws60
- Royal Oak Place Ws60
- Delany Wc60
- Psmcsd - Blackie Rd Ws60
- Chetmoore Acres Wa59
- Thimio Mwc59
- Glen Oaks Ws #0159
- Tierra Meadows Hoa Ws58
- Growers Transplanting Ws58
- Rancho Chaparral Mwc58
- Woodland Heights Mwc57
- Desmond Rd Ws #0356
- Green Acres Wa56
- Graves School Ws56
- Jost Post Wa56
- Marina Landfill Ws55
- Cachagua Mutual Ws (#4)55
- Del Monte Farms Rd Ws #0355
- Tierra Vista Mwc54
- Corda Rd Ws54
- Apricot Ln Ws53
- Oak Park Ws53
- Dolan Rd Water System #250
- Lucia Ws50
- Church of the Good Shepherd Ws50
- Hilltop Mwa50
- Gorda Ws50
- Onitsuka Brothers Ws50
- Pesante Rd Ws #0650
- Top Industries Ws50
- River Rd Ws #2649
- San Juan Rd Ws #0149
- Baumann Rd Ws #0148
- Paradise Rd Ws #2148
- Tierra Verde Mwc48
- Maher Rd Ws #0548
- Faith and Family Farms Ws47
- Foothill Wa46
- Echo Valley Rd Ws #0545
- Mount Toro Ranchos Mwa45
- Kendall-Jackson Winery Ws45
- Camphora Station Ws45
- San Miguel Ws #0345
- Sunny Acres Mws45
- Spreckels Ln Ws #0345
- Lhoist North America Ws44
- New Camaldoli Hermitage Ws44
- Paradise Rd Ws #0542
- Brandon Creek Mws41
- Harrison Rd Ws #0140
- Emerald Valley-Zabala Ws40
- Riverview Farms Ws40
- Berry Dr Ws #0240
- Alba Ws40
- Calera Canyon Heights Hoa40
- Meridian Rd Ws #0937
- Vierra Canyon Ws #2936
- Royal Sierra Estates Ws36
- Pine St Ws #0136
- Partington Mwc35
- Prunedale Chevron Ws35
- Natividad Rd Ws #0235
- Deetjen'S Big Sur Inn Ws35
- Williams - Rc Farms Ws35
- Outlook Wa35
- Royal Oaks Market Ws33
- Orchard Ln Ws #0232
- Spreckels Ln Ws #0231
- Garland Park30
- South Coast Center Ws30
- Cal Am Water Company - Garrapata30
- Bud Antle, LLC-Salinas Transplant Ws30
- River Rd Ws #2830
- Green Valley Floral-Potter Rd Ws30
- Massa Estate Vineyards Ws (Prev Heller)30
- Pezzini Farms Ws30
- Orchard Ln Ws #0930
- Mccahon Floral Ws29
- San Saba Winery Ws29
- Pentecostal Ws29
- Rosehart Industrial Park Ws28
- All Saints Campground Ws27
- White Rock Club Ws27
- Oasis Cafe Ws27
- Harrington Rd Ws #0726
- Sanctuary Bible Church Ws25
- Treebones Resort Ws25
- Cachagua Comm Ctr Ws25
- Exxon Station Ws25
- Old Stage Rd Ws #2125
- Kind Real Estate, LLC Ws25
- Spence Rd Ws #0525
- American Legion #593 Ws25
- Horn Ws25
- Garden Court Ws #0125
- Coast Gallery Ws25
- Spence Rd Cultivation Ws25
- El Camino Machine & Welding Ws25
- Bradley-Lockwood Rd Ws25
- Alisal Rd Ws #3 - 2262 Alisal Rd25
- Unitarian Universalist Church Ws25
- Monterey Mushrooms - Hall Rd25
- Bernardo Rd Ws #0225
- Conundrum Winery Ws25
- Altman Plants Ws #05 -Esp 325 (Prev Cs2)25
- Premium Packing Inc. Ws25
- Ponderosa Campgrounds Ws25
- Parkfield Cafe and Inn Ws25
- Henry Miller Library25
- Op Murphy & Sons Ws25
- Pacific Reserve Nursery Ws25
- Camphora-Gloria Rd Ws #0125
- Folktale Winery Ws25
- Grange Hall Ws25
Monterey County water systems: frequently asked questions
How many public water systems are in Monterey County, California?
EPA's SDWIS records file 307 active public water systems under Monterey County, California: 155 community systems (50%), 87 non-transient non-community systems (28%) and 65 transient non-community systems (21%).
Who supplies drinking water in Monterey County, CA?
The largest community water systems filed under Monterey County are Cwsc Salinas (123,679 people served), Cal Am Water Company - Monterey (92,450 people served) and Alco Water Service (56,253 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.
Does Monterey County's drinking water come from groundwater or surface water?
Of the 307 active public water systems in Monterey County, 96% draw mainly on groundwater and 3.9% on surface water, counting purchased supplies. The largest system, Cwsc Salinas, uses groundwater.
Where can I find a water quality report for Monterey County?
Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 155 community systems are filed under Monterey County, so the report to look for is the one from the system that supplies your address.
How can I check violations for a water system in Monterey County?
Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.
More California water systems
- All California public water systems· 7,479 active
- Sonoma County· 441 systems
- Fresno County· 328 systems
- Kern County· 327 systems
- San Bernardino County· 306 systems
- San Joaquin County· 302 systems
- Los Angeles County· 275 systems
- How to find out who supplies your drinking water
- How to find and read your annual water quality report
About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Public water systems in Monterey County, California”, https://aquacensus.com/water-systems/california/monterey (data as of October 1, 2026).