Water Quality in San Luis Obispo, CA (93401)
EPA violation data for public water systems serving ZIP code 93401.
Active Health Violations
25 health-based violations found in the past 5 years, with at least one still unresolved. Contaminant levels have exceeded federal safety limits. Consider testing your tap water independently.
More violations than 90% of US ZIP codes.
Based on EPA compliance data. Not a substitute for an official water quality report from your utility.
29,202
Population
71
Water Systems
50
Violations (5yr)
25
Health-Based
Location
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Water Systems Serving This Area (71)
Santa Margarita Recreation Area
San Luis Obispo Water Department
City Of Paso Robles Water Division
Atascadero Mutual Water Co
California Mens Colony
California Mens Colony
Cal Trans - Gaviota Rsr
Caltrans Camp Roberts Rsra Sb
All resolvedCaltrans Camp Roberts Rsra Nb
All resolvedTiger Water Supply
Caltrans - Shandon Rest Stop
1 health-basedGreengate Ranch & Vineyards
Santa Margarita Ranch Headquarters
Fiero Lane Water Company, Inc.
Ernie Ball, Inc
Strasbaugh, Inc
All resolvedJack Ready Imagination Park
Vachell Water System
1 health-basedGran Cielo Mutual Water Company
Callender Grove Mutual Water
All resolvedMadonna Inn Water Company
1 health-basedLas Ventanas Ranch
San Luis Business Park
Cuesta Motel Apartments - Inactive
Noll Properties
Zoo Med-Winterhaven
All resolvedBaron Canyon Mutual Water Co.
All resolvedAfuera De Chorro Water Company
All resolvedCreekside Commercial Center
San Luis Sourdough - Inactive
East Airport Fiero Lane Water Company
House Of Prayer
Copeland'S Distribution Center
Elks Lodge #322
1 health-basedChamisal Vineyards
Chevron
Goodwill Industries
Playa Dulce
Parsons Water Supply
Tank Farm Industrial Plaza
Wallace Water Systems
Pacific Bell Se-164
Waste Connections Water Co
All resolvedPeppertree Park Water Supply
P G & E Company Service Center - Inactiv
Ups - San Luis Obispo
J M Sims Water Supply
Horizon Lane Water Supply
Holdgrafer & Associates
Higuera Apartments
19 health-basedWilliams Water Co
Slo County Farm Bureau
De Royal Lmb - Inactive
Dana Ice Company - Inactive
Santa Fe Airpark
Design Alliance - Inactive
This Old House
200 Suburban Road Water Supply
Edna Valley Vineyards
All resolvedNiner Wine Estates, Llc
Buttonwood Industrial Park
Plumbers & Steamfitters - Inactive
Sunset Drive-In Snack Bar
1 health-basedUnion Properties
Independence Water System
141 Suburban Road Water Supply
1 health-basedCryolab Incorporated - Inactive
Gerald E Brewster - Inactive
Harmony Water Works
San Luis Water & Power
Hidden Hills Mobilodge
Contaminants Found
At high levels, nitrate can cause blue baby syndrome in infants.
Missed testing deadlines — not a detection of bacteria.
Lead and copper testing requirement. Lead exposure can cause developmental harm in children.
Lead & Copper Levels
Lead (Pb)
Within limitSampled: Jan 2025
How Does This Compare?
San Luis Obispo (93401) has more violations than 90% of US ZIP codes. The national average is 18.87 violations per ZIP over 5 years. This ZIP has 50.
Recommended Water Filters
Based on health-based violations detected in your area, these filter types are commonly used to address similar contaminants. Consult your water utility's Consumer Confidence Report for the most current data.
Reverse Osmosis System
Highly effective at removing heavy metals, dissolved solids, and a wide range of contaminants. Recommended for homes with lead or arsenic concerns.
Targets:Lead, Copper, Arsenic, Mercury, Cadmium
Look for:NSF/ANSI 58 certified
UV Water Purifier
Uses ultraviolet light to neutralize bacteria, viruses, and parasites without chemicals. Ideal for homes with microbial contamination concerns.
Targets:E. coli, Coliform, Giardia, Cryptosporidium
Look for:NSF/ANSI 55 (Class A) certified
Always look for filters certified by NSF International for the specific contaminants you want to remove. This is general educational information, not an endorsement of any specific product.