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Results for San Luis Obispo County, CA

252 water providers on file for this county, sorted by population served.

Quick answer: San Luis Obispo County has 252 water providers profiled, sorted by population served.

Lead Summary
Nitrate
Copper Summary
Chromium, Hex
TDS
Iron
PFPEA
Lithium
PFHXS
PFOS
PFOA
PFHXA
PFBS
Manganese
Perfluorobutanesulfonicacid (PFBS)
Perfluoroheptanoicacid (PFHPA)
Perfluorohexanesulfonicacid (PFHxS)
Perfluoroctanesulfonicacid (PFOS)
Perfluoroctanoicacid (PFOA)
Perfluorohexanoicacid (PFHXA)
Perfluorobutanoicacid (PFBA)
Perfluoropentanoicacid (PFPEA)
Totalhaloaceticacids (HAA5)
TTHM
Chloroform
Bromoform
Bromodichloromethane
Dibromochloromethane
Dichloroaceticacid
Trichloroaceticacid
Dibromoaceticacid
Copper, Free
PFBA
Arsenic
Monobromoaceticacid
Monochloroaceticacid
Aggressive Index
Temperature (CENTIGRADE)
Magnesium
Calcium
Hardness, Total (ASCACO3)
Potassium
Sodium
Alkalinity, Total
Alkalinity, Bicarbonate
Foamingagents (SURFACTANTS)
Chloride
Sulfate
Fluoride
Turbidity
pH
Odor
Nickel
Barium
Zinc
Conductivity (at 25°C)
Color
Langelier Index (pH(s))
Nitrate-Nitrite
Perchlorate
Selenium
Langelier Index (Source Temp.)
Boron, Total
Lead
PFHPA
Perfluoropentanesulfonicacid (PFPES)
Radium-228
Combined Uranium
Gross Alpha Particle Activity
Vanadium, Total
Tetrachloroethylene
Carbon, Total
pH, Field
Aluminum
Nitrite
Chromium
1, 2, 3-Trichloropropane
Bromate
Trichloroethylene
Radium-226
Combined Radium (-226 & -228)
Sulfide
Adsorbableorganicfluorine
Perfluorononanoicacid (PFNA)
Perfluoroheptanesulfonicacid (PFHPS)
1, 1-Dichloroethylene
Chlorite
Turbidity, Field
Silica
Strontium
Totalnitrogen (ASN)
Asbestos
Pfpes
Cadmium
Mercury

Violations on file

Selenium

Older/archived health-based violation

Found at 6 of 252 providers

Nitrate

Older/archived health-based violation

Found at 5 of 252 providers

Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.

Lead And Copper Rule Revisions

Currently open health violation

Found at 8 of 252 providers

Total Haloacetic Acids (HAA5)

Older/archived health-based violation

Found at 1 of 252 providers

Coliform (TCR)

Older/archived health-based violation

Found at 1 of 252 providers

Contaminants found

Metals

Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper

Lead Summary

Detected: 0.065 mg/L (ppm)

Found at 131 providers

Copper Summary

Detected: 2.8 mg/L (ppm)

Found at 20 providers

Chromium, Hex

Detected: 16 UG/L (ppb)

Found at 50 providers

Iron

Detected: 19000 UG/L (ppb)

Found at 36 providers

Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.

Manganese

Detected: 700 UG/L (ppb)

Found at 34 providers

Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.

Copper, Free

Detected: 2100 UG/L (ppb)

Found at 50 providers

Arsenic

Detected: 38 UG/L (ppb)

Found at 35 providers

Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.

Nickel

Detected: 48 UG/L (ppb)

Found at 12 providers

Barium

Detected: 2100 UG/L (ppb)

Found at 42 providers

Zinc

Detected: 510 UG/L (ppb)

Found at 16 providers

Selenium

Detected: 160 UG/L (ppb)

Found at 36 providers

Lead

Detected: 14 UG/L (ppb)

Found at 20 providers

A metal that can leach from old pipes, solder, and fixtures. Current medical guidance holds there is no truly safe level of lead exposure, especially for children and pregnant women.

Combined Uranium

Detected: 11.7 PCI/L

Found at 9 providers

A naturally occurring radioactive metal. Long-term exposure above the legal limit is associated with kidney effects and increased cancer risk.

Vanadium, Total

Detected: 16 UG/L (ppb)

Found at 3 providers

Aluminum

Detected: 870 UG/L (ppb)

Found at 7 providers

Chromium

Detected: 25 UG/L (ppb)

Found at 15 providers

Occurs in two forms — trivalent (an essential nutrient in trace amounts) and hexavalent (linked to increased cancer risk).

Strontium

Detected: 550 UG/L (ppb)

4/1/2025

Cadmium

Detected: 12 UG/L (ppb)

Found at 2 providers

Mercury

Detected: 1.4 UG/L (ppb)

1/20/2025

Disinfection Byproducts

Formed when chlorine used to disinfect water reacts with organic matter

Totalhaloaceticacids (HAA5)

Detected: 49 UG/L (ppb)

Found at 40 providers

TTHM

Detected: 150 UG/L (ppb)

Found at 55 providers

A group of disinfection byproducts formed when chlorine reacts with organic matter. Long-term exposure above the legal limit has been linked to increased cancer risk in some studies.

Chloroform

Detected: 81 UG/L (ppb)

Found at 45 providers

One of the individual trihalomethane disinfection byproducts, formed when chlorine reacts with organic matter.

Bromoform

Detected: 55 UG/L (ppb)

Found at 46 providers

Bromodichloromethane

Detected: 45 UG/L (ppb)

Found at 48 providers

Dibromochloromethane

Detected: 42 UG/L (ppb)

Found at 53 providers

Inorganics

Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride

Nitrate

Detected: 17 MG/L (ppm)

Found at 92 providers

Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.

Chloride

Detected: 1300 MG/L (ppm)

Found at 43 providers

Sulfate

Detected: 500 MG/L (ppm)

Found at 42 providers

Fluoride

Detected: 1.3 MG/L (ppm)

Found at 51 providers

Often added deliberately for dental health; can also occur naturally.

Nitrate-Nitrite

Detected: 14 MG/L (ppm)

Found at 43 providers

Boron, Total

Detected: 400 UG/L (ppb)

Found at 14 providers

Nitrite

Detected: 0.44 MG/L (ppm)

4/1/2025

Minerals

Everyday minerals that mainly affect taste and water hardness

Magnesium

Detected: 280 MG/L (ppm)

Found at 41 providers

Calcium

Detected: 250 MG/L (ppm)

Found at 42 providers

Potassium

Detected: 6 MG/L (ppm)

Found at 34 providers

Sodium

Detected: 260 MG/L (ppm)

Found at 41 providers

Properties

General water characteristics like pH, hardness, and cloudiness (turbidity)

Hardness, Total (ASCACO3)

Detected: 1700 MG/L (ppm)

Found at 39 providers

Detected: 8.42 PH

Found at 31 providers

A measure of how acidic or basic the water is (7 is neutral). Affects taste and plumbing, not a direct health measure.

Langelier Index (pH(s))

Detected: 1.3 LANG

Found at 18 providers

Gross Alpha Particle Activity

Detected: 18.4 PCI/L

Found at 30 providers

pH, Field

Detected: 8.5 PH

Found at 12 providers

PFAS & Emerging Contaminants

Human-made "forever chemicals" and other substances not yet fully regulated

PFPEA

Detected: 0.017 µg/L (ppb)

Found at 5 providers

Lithium

Detected: 40.5 µg/L (ppb)

Found at 10 providers

Occurs naturally in some groundwater. Not currently federally regulated in drinking water.

PFHXS

Detected: 0.0084 µg/L (ppb)

Found at 7 providers

PFOS

Detected: 0.0117 µg/L (ppb)

Found at 4 providers

One of two PFAS with an enforceable federal limit (4 ppt) since 2024.

PFOA

Detected: 0.0147 µg/L (ppb)

Found at 4 providers

One of two PFAS with an enforceable federal limit (4 ppt) since 2024.

PFHXA

Detected: 0.0166 µg/L (ppb)

Found at 5 providers

PFBS

Detected: 0.018 µg/L (ppb)

Found at 7 providers

PFBA

Detected: 0.01 µg/L (ppb)

Found at 3 providers

PFHPA

Detected: 0.0054 µg/L (ppb)

Found at 2 providers

Pfpes

Detected: 0.0061 µg/L (ppb)

2/8/2023

VOCs (Volatile Organic Compounds)

Industrial solvents and fuel-related chemicals that evaporate easily

Tetrachloroethylene

Detected: 8.3 UG/L (ppb)

Found at 3 providers

1, 2, 3-Trichloropropane

Detected: 0.0055 UG/L (ppb)

10/7/2025

Trichloroethylene

Detected: 13 UG/L (ppb)

10/2/2025

1, 1-Dichloroethylene

Detected: 1.2 UG/L (ppb)

7/8/2025

Calculated Parameters

Values worked out mathematically from other test results, not measured directly

Alkalinity, Bicarbonate

Detected: 430 MG/L (ppm)

Found at 40 providers

Other

Additional substances tested that don't fit neatly into the categories above

TDS

Detected: 2100 MG/L (ppm)

Found at 46 providers

Perfluorobutanesulfonicacid (PFBS)

Detected: 260 NG/L (ppt)

Found at 19 providers

Perfluoroheptanoicacid (PFHPA)

Detected: 130 NG/L (ppt)

Found at 11 providers

Perfluorohexanesulfonicacid (PFHxS)

Detected: 1100 NG/L (ppt)

Found at 18 providers

Perfluoroctanesulfonicacid (PFOS)

Detected: 44 NG/L (ppt)

Found at 19 providers

One of two PFAS with an enforceable federal limit (4 ppt) since 2024.

Perfluoroctanoicacid (PFOA)

Detected: 86 NG/L (ppt)

Found at 13 providers

One of two PFAS with an enforceable federal limit (4 ppt) since 2024.

Perfluorohexanoicacid (PFHXA)

Detected: 360 NG/L (ppt)

Found at 12 providers

Perfluorobutanoicacid (PFBA)

Detected: 110 NG/L (ppt)

Found at 14 providers

Perfluoropentanoicacid (PFPEA)

Detected: 320 NG/L (ppt)

Found at 12 providers

Dichloroaceticacid

Detected: 30 UG/L (ppb)

Found at 33 providers

Trichloroaceticacid

Detected: 26.4 UG/L (ppb)

Found at 32 providers

Dibromoaceticacid

Detected: 11 UG/L (ppb)

Found at 42 providers

Monobromoaceticacid

Detected: 1.1 UG/L (ppb)

Found at 6 providers

Monochloroaceticacid

Detected: 5.3 UG/L (ppb)

Found at 12 providers

Aggressive Index

Detected: 13.2 AGGR

Found at 39 providers

Temperature (CENTIGRADE)

Detected: 24.6 C

Found at 18 providers

Alkalinity, Total

Detected: 430 MG/L (ppm)

Found at 42 providers

Foamingagents (SURFACTANTS)

Detected: 0.13 MG/L (ppm)

Found at 4 providers

Turbidity

Detected: 70 NTU

Found at 31 providers

A measure of water cloudiness from suspended particles.

Odor

Detected: 24 TON

Found at 14 providers

Conductivity (at 25°C)

Detected: 3900 UMHO/CM

Found at 48 providers

Color

Detected: 22 UNITS

Found at 15 providers

Perchlorate

Detected: 1.7 UG/L (ppb)

Found at 4 providers

Can occur naturally or from industrial/military sources; may interfere with thyroid function at elevated levels.

Langelier Index (Source Temp.)

Detected: 1.1 LANG

Found at 8 providers

Perfluoropentanesulfonicacid (PFPES)

Detected: 260 NG/L (ppt)

Found at 8 providers

Radium-228

Detected: 1.09 PCI/L

Found at 10 providers

Carbon, Total

Detected: 3.5 MG/L (ppm)

Found at 5 providers

Bromate

Detected: 4.8 UG/L (ppb)

Found at 2 providers

Radium-226

Detected: 3.53 PCI/L

Found at 3 providers

Combined Radium (-226 & -228)

Detected: 4.5 PCI/L

Found at 7 providers

A naturally occurring radioactive element found in some groundwater.

Sulfide

Detected: 11 MG/L (ppm)

10/20/2025

Adsorbableorganicfluorine

Detected: 1000 NG/L (ppt)

3/10/2025

Perfluorononanoicacid (PFNA)

Detected: 4.9 NG/L (ppt)

Found at 2 providers

Perfluoroheptanesulfonicacid (PFHPS)

Detected: 4.5 NG/L (ppt)

6/19/2025

Chlorite

Detected: 1.3 MG/L (ppm)

10/6/2025

Turbidity, Field

Detected: 1.7 NTU

Found at 4 providers

Silica

Detected: 54 MG/L (ppm)

4/1/2025

Totalnitrogen (ASN)

Detected: 0.99 MG/L (ppm)

7/21/2025

Asbestos

Detected: 8.3 MFL

9/10/2025

Filtration considerations: General system types, not a specific product recommendation.

Contaminant	Whole-House Carbon	Under-Sink RO	Under-Sink Carbon
Total Trihalomethanes (TTHM)	Yes	Yes	Yes
Haloacetic Acids (HAA5)	Yes	Yes	Yes
Chloroform	Yes	Yes	Yes
Chlorine / Taste	Yes	Yes	Yes
Sediment / Turbidity	Yes	Yes	Yes
Trichloroethylene	Yes	Yes	Yes
Tetrachloroethylene	Yes	Yes	Yes
cis-1,2-Dichloroethylene	Yes	Yes	Yes
1,1-Dichloroethylene	Yes	Yes	Yes
Bromoform	Yes	Yes	Yes
Bromodichloromethane	Yes	Yes	Yes
Dibromochloromethane	Yes	Yes	Yes
1,1,2-Trichloroethane	Yes	Yes	Yes
Vinyl Chloride	Yes	Yes	Yes
Carbon Tetrachloride	Yes	Yes	Yes
Benzene	Yes	Yes	Yes
Toluene	Yes	Yes	Yes
Xylene	Yes	Yes	Yes
Totalhaloaceticacids (HAA5)	Yes	Yes	Yes
1, 2, 3-Trichloropropane	Yes	Yes	Yes
Lead	Partial	Yes	Partial
Arsenic	Partial	Yes	Partial
Chromium-6 (Hexavalent)	Partial	Yes	Partial
Copper	Partial	Yes	Partial
Combined Uranium	Partial	Yes	Partial
PFOA	Partial	Yes*	Partial
PFOS	Partial	Yes*	Partial
Nitrate	Partial	Yes	Partial
Combined Radium	Partial	Yes	Partial
Chromium, Hex	Partial	Yes	Partial
TDS	Partial	Yes	Partial
Iron	Partial	Yes	Partial
PFPEA	Partial	Yes*	Partial
Lithium	Partial	Yes*	Partial
PFHXS	Partial	Yes*	Partial
PFHXA	Partial	Yes*	Partial
PFBS	Partial	Yes*	Partial
Manganese	Partial	Yes	Partial
Perfluorobutanesulfonicacid (PFBS)	Partial	Yes	Partial
Perfluoroheptanoicacid (PFHPA)	Partial	Yes	Partial
Perfluorohexanesulfonicacid (PFHxS)	Partial	Yes	Partial
Perfluoroctanesulfonicacid (PFOS)	Partial	Yes	Partial
Perfluoroctanoicacid (PFOA)	Partial	Yes	Partial
Perfluorohexanoicacid (PFHXA)	Partial	Yes	Partial
Perfluorobutanoicacid (PFBA)	Partial	Yes	Partial
Perfluoropentanoicacid (PFPEA)	Partial	Yes	Partial
Dichloroaceticacid	Partial	Yes	Partial
Trichloroaceticacid	Partial	Yes	Partial
Dibromoaceticacid	Partial	Yes	Partial
Copper, Free	Partial	Yes	Partial
PFBA	Partial	Yes*	Partial
Monobromoaceticacid	Partial	Yes	Partial
Monochloroaceticacid	Partial	Yes	Partial
Aggressive Index	Partial	Yes	Partial
Temperature (CENTIGRADE)	Partial	Yes	Partial
Alkalinity, Total	Partial	Yes	Partial
Foamingagents (SURFACTANTS)	Partial	Yes	Partial
Chloride	Partial	Yes	Partial
Sulfate	Partial	Yes	Partial
Fluoride	Partial	Yes	Partial
Odor	Partial	Yes	Partial
Nickel	Partial	Yes	Partial
Barium	Partial	Yes	Partial
Zinc	Partial	Yes	Partial
Conductivity (at 25°C)	Partial	Yes	Partial
Color	Partial	Yes	Partial
Nitrate-Nitrite	Partial	Yes	Partial
Perchlorate	Partial	Yes	Partial
Selenium	Partial	Yes	Partial
Langelier Index (Source Temp.)	Partial	Yes	Partial
Boron, Total	Partial	Yes	Partial
PFHPA	Partial	Yes*	Partial
Perfluoropentanesulfonicacid (PFPES)	Partial	Yes	Partial
Combined Uranium	Partial	Yes	Partial
Vanadium, Total	Partial	Yes	Partial
Carbon, Total	Partial	Yes	Partial
Aluminum	Partial	Yes	Partial
Nitrite	Partial	Yes	Partial
Chromium	Partial	Yes	Partial
Bromate	Partial	Yes	Partial
Radium-226	Partial	Yes	Partial
Combined Radium (-226 & -228)	Partial	Yes	Partial
Sulfide	Partial	Yes	Partial
Adsorbableorganicfluorine	Partial	Yes	Partial
Perfluorononanoicacid (PFNA)	Partial	Yes	Partial
Perfluoroheptanesulfonicacid (PFHPS)	Partial	Yes	Partial
Chlorite	Partial	Yes	Partial
Turbidity, Field	Partial	Yes	Partial
Silica	Partial	Yes	Partial
Strontium	Partial	Yes	Partial
Totalnitrogen (ASN)	Partial	Yes	Partial
Asbestos	Partial	Yes	Partial
Pfpes	Partial	Yes*	Partial
Cadmium	Partial	Yes	Partial
Mercury	Partial	Yes	Partial
Coliform Bacteria (indicator)	No	Yes	No
Magnesium	No	Partial	No
Calcium	No	Partial	No
Hardness, Total (ASCACO3)	No	No	No
Potassium	No	Partial	No
Sodium	No	Partial	No
Alkalinity, Bicarbonate	No	No	No
pH	No	No	No
Langelier Index (pH(s))	No	No	No
Gross Alpha Particle Activity	No	No	No
pH, Field	No	No	No

Browse by city

Individual water providers

SANTA MARGARITA RECREATION AREA No violations on file — pop. 50,001
SAN LUIS OBISPO WATER DEPARTMENT No violations on file — pop. 47,788
CITY OF PASO ROBLES WATER DIVISION No violations on file — pop. 31,176
ATASCADERO MUTUAL WATER CO No violations on file — pop. 30,618
CITY OF ARROYO GRANDE UTILITIES DIVISION No violations on file — pop. 17,963
CALIFORNIA MENS COLONY No violations on file — pop. 15,000
NIPOMO COMM SERVICES DIST No violations on file — pop. 13,771
MORRO BAY PW DEPT - WATER DIVISION No violations on file — pop. 13,757
CITY OF GROVER BEACH PUBLIC WORKS DEPT No violations on file — pop. 12,701
BRECON ESTATE No violations on file — pop. 9,012 — serves SAN SIMEON
CALIFORNIA MENS COLONY No violations on file — pop. 8,900
CALIFORNIA MENS COLONY No violations on file — pop. 8,900

PISMO BEACH WATER DEPARTMENT No violations on file — pop. 8,036
TEMPLETON CSD No violations on file — pop. 8,011
OCEANO COMM SERVICES DIST. No violations on file — pop. 7,601
LOS OSOS COMMUNITY SERVICES DISTRICT No violations on file — pop. 7,086
GOLDEN STATE WATER COMPANY - LOS OSOS No violations on file — pop. 5,924
CAMBRIA COMM SERVICES DIST No violations on file — pop. 5,532
GOLDEN STATE WATER COMPANY - NIPOMO No violations on file — pop. 4,506
ATASCADERO STATE HOSPITAL No violations on file — pop. 4,100
WOODLANDS DEVELOPMENT No violations on file — pop. 3,862
GROSSO KRESSER WINERY No violations on file — pop. 3,606 — serves SAN SIMEON
HERITAGE RANCH CSD No violations on file — pop. 2,956
SAN MIGUEL COMMUNITY SERVICES DISTRICT No violations on file — pop. 2,600
CAYUCOS BEACH MUTUAL WATER COMPANY No violations on file — pop. 2,567
MORRO ROCK MUTUAL WATER CO No violations on file — pop. 2,181
NACIMIENTO WATER COMPANY Older violation on record — pop. 2,181
GOLDEN STATE WATER COMPANY-CYPRESS RIDGE No violations on file — pop. 2,026
AGNEWS RESIDENTIAL FACILITY No violations on file — pop. 1,903
ATASCADERO STATE HOSPITAL No violations on file — pop. 1,900
ATASCADERO STATE HOPSITAL No violations on file — pop. 1,900
AVILA BEACH COMMUNITY SERVICES DISTRICT No violations on file — pop. 1,630
SAN MIGUELITO MWC No violations on file — pop. 1,600
TIGER WATER SUPPLY No violations on file — pop. 1,600
LOPEZ PROJECT No violations on file — pop. 1,569
COUNTY OF MONTEREY-LAKE NACIMIENTO No violations on file — pop. 1,521
GOLDEN STATE WATER COMPANY - EDNA No violations on file — pop. 1,493
CALTRANS - SHANDON REST STOP No violations on file — pop. 1,300
SLO CWWD NO. 23 - SANTA MARGARITA No violations on file — pop. 1,291
PG&E No violations on file — pop. 1,200
SLOCSA #10A - CAYUCOS No violations on file — pop. 1,200
SLO CSA NO. 16 - SHANDON No violations on file — pop. 1,085
DAOU VINEYARDS, LLC No violations on file — pop. 1,025
MONTANA DE ORO STATE PARK No violations on file — pop. 990
LAUREATE WATER COMPANY No violations on file — pop. 700
COASTAL CHRISTIAN SCHOOL No violations on file — pop. 650
MESA DUNES MOBILE HOME ESTATES No violations on file — pop. 600
S & T MUTUAL WATER COMPANY No violations on file — pop. 591
WOODLAND PARK MUTUAL WATER CO Older violation on record — pop. 538
GREENGATE RANCH & VINEYARDS No violations on file — pop. 503
HEARST MEMORIAL STATE BEACH No violations on file — pop. 500
WALNUT HILLS MUTUAL WATER CO No violations on file — pop. 486
SAN SIMEON CSD No violations on file — pop. 462
GARDEN FARMS C.W.D. No violations on file — pop. 440
LOS ROBLES MOBILE HOME ESTATES No violations on file — pop. 420
VINES R.V. RESORT No violations on file — pop. 400
SANTA MARGARITA RANCH HEADQUARTERS No violations on file — pop. 362 — serves CAYUCOS
GREEN RIVER MUTUAL WATER CO. Open violation — pop. 350
SANTA YSABEL RANCH MWC No violations on file — pop. 344
FIERO LANE WATER COMPANY, INC. Older violation on record — pop. 324
ERNIE BALL, INC No violations on file — pop. 300
LAETITIA VINEYARD & WINERY INC No violations on file — pop. 270
GOLDBERG BROTHERS PROPERTIES, INC. No violations on file — pop. 261
BRANCH ELEMENTARY SCHOOL No violations on file — pop. 253
RANCHO COLINA MOBILE HOME PARK No violations on file — pop. 249
CAL SHASTA CLUB No violations on file — pop. 240
PARRISH FAMILY WINERY No violations on file — pop. 207
STRASBAUGH, INC No violations on file — pop. 200
SYCAMORE MINERAL SPRINGS RESORT Open violation — pop. 200
HEARST MONUMENT STATE PARK No violations on file — pop. 200
BELLA VISTA MOBILE LODGE No violations on file — pop. 200
OCTAGON BARN CENTER ASSOCIATION No violations on file — pop. 200
JACK READY IMAGINATION PARK No violations on file — pop. 200 — serves CAYUCOS
COAST UNION HIGH SCHOOL No violations on file — pop. 150
VACHELL WATER SYSTEM Open violation — pop. 150
GRAN CIELO MUTUAL WATER COMPANY No violations on file — pop. 139 — serves SAN SIMEON
PASO 360 No violations on file — pop. 135
IRISH HILLS MUTUAL WATER CO No violations on file — pop. 135
CANYON CREST MUTUAL BENEFIT WC No violations on file — pop. 133
CHRISTMAS COVE No violations on file — pop. 132
EDNA VALLEY RANCH EAST No violations on file — pop. 132
CALLENDER GROVE MUTUAL WATER No violations on file — pop. 126
SPANISH LAKES MUTUAL WATER CO No violations on file — pop. 125
PORT SAN LUIS HARBOR DISTRICT No violations on file — pop. 125
COURTSIDE CELLARS No violations on file — pop. 125 — serves SAN SIMEON
MADONNA INN WATER COMPANY Open violation — pop. 120
HALCYON WATER SYSTEM Older violation on record — pop. 110
LAS VENTANAS RANCH No violations on file — pop. 108
VARIAN RANCH MUTUAL WATER No violations on file — pop. 105
PASO ROBLES RV RANCH No violations on file — pop. 105
CLEARWATER NURSERY No violations on file — pop. 100
MORRO BAY MUTUAL WATER CO No violations on file — pop. 100
NOLL PROPERTIES No violations on file — pop. 100
RAGGED POINT INN No violations on file — pop. 100
LOPEZ RECREATION AREA No violations on file — pop. 100
PLEASANT VALLEY ELEMENTARY No violations on file — pop. 100
CRESTON ELEMENTARY SCHOOL No violations on file — pop. 100
SAN LUIS BUSINESS PARK No violations on file — pop. 100
SANTA MARIA SPEEDWAY No violations on file — pop. 100
RESTHAVEN MOBILE HOME PARK Older violation on record — pop. 99
LE CUVIER WINERY No violations on file — pop. 92 — serves CAYUCOS
GREENHEART FARMS No violations on file — pop. 91
PACIFIC DUNES RANCH No violations on file — pop. 89
TRI COUNTIES CLUB No violations on file — pop. 87
BASSI RANCH MUTUAL WATER CO. No violations on file — pop. 85
ZOO MED-WINTERHAVEN No violations on file — pop. 85 — serves CAYUCOS
KEN MAR GARDENS Older violation on record — pop. 84
BARON CANYON MUTUAL WATER CO. No violations on file — pop. 81
KEEP OCEAN No violations on file — pop. 80
LAGUNA NEGRA MUTUAL WATER CO. No violations on file — pop. 80
AFUERA DE CHORRO WATER COMPANY No violations on file — pop. 79
ADELAIDA VINEYARDS & WINERY No violations on file — pop. 77 — serves SAN SIMEON
CREEKSIDE COMMERCIAL CENTER No violations on file — pop. 75
USASA-POM ENCLAVE - CAMP ROBERTS No violations on file — pop. 75
CENTER OF EFFORT WINERY No violations on file — pop. 75
AVILA VALLEY MUTUAL WATER CO No violations on file — pop. 75
TALLEY FARMS LABOR HOUSING No violations on file — pop. 75
WHITSON INDUSTRIAL PARK No violations on file — pop. 75
SUTTER HOME WINERY INC. TRINCHERO CC No violations on file — pop. 71
H2O, INC No violations on file — pop. 70
SANTA MARGARITA KOA No violations on file — pop. 70
MONTE SERENO MUTUAL BENEFIT WATER No violations on file — pop. 65
SAN LUIS SOURDOUGH - INACTIVE No violations on file — pop. 60
BALL TAGAWA GROWERS No violations on file — pop. 60
ANZA VINEYARD ESTATES MUTUAL WATER CO No violations on file — pop. 60
COUNTRY HILLS ESTATES No violations on file — pop. 60
TOYOTA SAN LUIS OBISPO No violations on file — pop. 57
BOOKER WINERY No violations on file — pop. 56 — serves CAYUCOS
GRANDE MOBILE MANOR Older violation on record — pop. 55
RIM ROCK WATER COMPANY No violations on file — pop. 55
CARPENTER WINERY No violations on file — pop. 54 — serves CAYUCOS
SANTA LUCIA SCHOOL No violations on file — pop. 52
MT. OLIVE ORGANIC FARM No violations on file — pop. 51 — serves CAYUCOS
HOUSE OF PRAYER No violations on file — pop. 50
COPELAND'S DISTRIBUTION CENTER No violations on file — pop. 50
PARAGON TRIANGLE WATER SUPPLY No violations on file — pop. 50
NORTHSHORE S & B, INC No violations on file — pop. 50
LAGUNA VISTA BOAT CLUB No violations on file — pop. 50
GRANITE RIDGE No violations on file — pop. 50
KUKKULA INC No violations on file — pop. 50
HUNTER RANCH GOLF COURSE No violations on file — pop. 50
RANCHO SALINAS MBWC No violations on file — pop. 50
EAST AIRPORT FIERO LANE WATER COMPANY No violations on file — pop. 50
TANK FARM BUSINESS PARK No violations on file — pop. 45
BEAR VALLEY WATER COMPANY No violations on file — pop. 45
TRUMPET VINE CATERING No violations on file — pop. 45
BROOKSIDE TRACT No violations on file — pop. 44
RANCHO NIPOMO WATER COMPANY No violations on file — pop. 44
DOUBLE J MOBILE ESTATES Older violation on record — pop. 43
SAN SIMEON CREEK RANCH No violations on file — pop. 42
ELKS LODGE #322 Open violation — pop. 40
SPEEDLING, INC No violations on file — pop. 40
CARRISA PLAINS ELEMENTARY Older violation on record — pop. 40
SLO PARTNERS No violations on file — pop. 40
ALMIRA WATER ASSOCIATION No violations on file — pop. 40
CHAMISAL VINEYARDS No violations on file — pop. 40 — serves CAYUCOS
JADA VINEYARD AND WINERY No violations on file — pop. 40 — serves SAN SIMEON
FIRST BAPTIST CHURCH No violations on file — pop. 40
TERRA DE ORO WATER COMPANY No violations on file — pop. 38
GOODWILL INDUSTRIES No violations on file — pop. 35
WALLACE WATER SYSTEMS No violations on file — pop. 35
CHEVRON No violations on file — pop. 35
GUADALUPE COOLING COMPANY No violations on file — pop. 35
PARSONS WATER SUPPLY No violations on file — pop. 35
WASTE CONNECTIONS WATER CO No violations on file — pop. 35
BLACK MOUNTAIN R.V. RESORT No violations on file — pop. 35
PLAYA DULCE No violations on file — pop. 35
UPS - SAN LUIS OBISPO No violations on file — pop. 35
TANK FARM INDUSTRIAL PLAZA No violations on file — pop. 35
J M SIMS WATER SUPPLY No violations on file — pop. 34
HORIZON LANE WATER SUPPLY No violations on file — pop. 32
MUSTANG MOBILE VILLAGE No violations on file — pop. 31
SLO COUNTY FARM BUREAU No violations on file — pop. 30
CALIFORNIA VALLEY COMMUNITY SE No violations on file — pop. 30
JACK RANCH CAFE No violations on file — pop. 30
CROSSROADS/ HOUSE OF PRAYER No violations on file — pop. 30
CAELESTA WINERY No violations on file — pop. 30 — serves CAYUCOS
HIGUERA APARTMENTS Open violation — pop. 30
HOLDGRAFER & ASSOCIATES No violations on file — pop. 30
CERRO ALTO CAMPGROUND No violations on file — pop. 30
MUSTANG SPRINGS MUTUAL WATER No violations on file — pop. 30
WILLIAMS WATER CO No violations on file — pop. 30
MUTUAL WATER ASSOCIATION Open violation — pop. 30
LONGBRANCH SALOON, THE No violations on file — pop. 30
BROKEN EARTH WINERY No violations on file — pop. 28
BIDDLE REGIONAL COUNTY PARK No violations on file — pop. 27
POZO SALOON No violations on file — pop. 25
LINKS AT VISTA DEL HOMBRE, THE No violations on file — pop. 25
BUTTONWOOD INDUSTRIAL PARK No violations on file — pop. 25
PHILLIPS 66 COMPANY, SANTA MARIA FACILIT No violations on file — pop. 25
ATASCADERO LAKE - INACTIVE No violations on file — pop. 25
REDWOOD PAYLESS STATION No violations on file — pop. 25
HAZARD WATER SUPPLY No violations on file — pop. 25
SUBURBAN LODGE No violations on file — pop. 25
RAMONA MOTEL No violations on file — pop. 25
RICHARD NOCK, PRES No violations on file — pop. 25
HERMRECK SHOPPING CENTER No violations on file — pop. 25
RANCHO EL CHORRO SCHOOL No violations on file — pop. 25
GERALD E BREWSTER - INACTIVE No violations on file — pop. 25
RIFLE FAIRING WATER SUPPLY No violations on file — pop. 25
PARKS & RECREATION No violations on file — pop. 25
RAY W SHAMEL PARK No violations on file — pop. 25
SAN LUIS OBISPO No violations on file — pop. 25
HEDGER WATER SUPPLY - INACTIVE No violations on file — pop. 25
LOPEZ TROUT FARM - INACTIVE No violations on file — pop. 25
DESIGN ALLIANCE - INACTIVE No violations on file — pop. 25
OAK PARK MANOR No violations on file — pop. 25
PIEDRAS BLANCAS WATER SUPPLY No violations on file — pop. 25
UNION PROPERTIES No violations on file — pop. 25
7X YOUTH RANCH No violations on file — pop. 25
HALFWAY STATION No violations on file — pop. 25
BABE RUTH'S OAK VIEW No violations on file — pop. 25
PRECISION MUTUAL WATER COMPANY No violations on file — pop. 25
PASO ROBLES CHEVROLET CADILLAC No violations on file — pop. 25
SAN PASO TRUCK STOP No violations on file — pop. 25
SUNSET DRIVE-IN SNACK BAR No violations on file — pop. 25
141 SUBURBAN ROAD WATER SUPPLY Older violation on record — pop. 25
TMC SUBURBAN, LLC No violations on file — pop. 25
CRESTON COUNTRY STORE No violations on file — pop. 25
LOADING CHUTE No violations on file — pop. 25
INDEPENDENCE WATER SYSTEM No violations on file — pop. 25
SIXMILEBRIDGE WINERY No violations on file — pop. 25
ADA'S LODGES No violations on file — pop. 25
NINER WINE ESTATES, LLC No violations on file — pop. 25
ARONHILL VINEYARD No violations on file — pop. 25
CONGREGATION BETH DAVID No violations on file — pop. 25
CUYAMA LANE WATER COMPANY Open violation — pop. 25
HARMONY WATER WORKS No violations on file — pop. 25
EDNA VALLEY VINEYARDS No violations on file — pop. 25
INN AT OPOLO KITCHEN, THE No violations on file — pop. 25
200 SUBURBAN ROAD WATER SUPPLY No violations on file — pop. 25
NUNES WATER COMPANY No violations on file — pop. 24
MESA MUTUAL WATER COMPANY No violations on file — pop. 24
SAN LUIS WATER & POWER No violations on file — pop. 24
SWEET SPRINGS MOBILE PARK No violations on file — pop. 24
NEWSOM SPRINGS MUTUAL WATER CO No violations on file — pop. 24
VISTA DE LAS FLORES WATER No violations on file — pop. 24
HIDDEN HILLS MOBILODGE No violations on file — pop. 22
ESTRELLA CORRECTIONAL FACILITY Older violation on record — pop. 20
RANCHO OAKS MOBILE PARK No violations on file — pop. 19
ARROYO GRANDE MUSHROOM FARM No violations on file — pop. 12
VICTORIAN MANOR WATER SUPPLY No violations on file — pop. 10
RINCONADA TRAILER PARK No violations on file — pop. 10
CSP SAN SIMEON CREEK ST BEACH No violations on file — pop. 8
EMBERS CAFE No violations on file — pop. 4
UNION OIL COMPANY - SANTA MARI No violations on file — pop. 1
AVILA BEACH COUNTY WATER DIST No violations on file — pop. 0
SAN LUIS OBISPO CSA 1G- BLACK LAKE No violations on file — pop. 0 — serves BLACK LAKE
SLO CSA NO. 12 - AVILA BEACH No violations on file — pop. 0
CHORRO VALLEY PIPELINE - SLO COUNTY No violations on file — pop. 0
SLO CSA NO. 10 - CAYUCOS WTP No violations on file — pop. 0
NACIMIENTO WATER PROJECT No violations on file — pop. 0

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San Luis Obispo County, CA Water Quality Report

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