Tapcensus

Water quality for ZIP code 93420

ZIP 93420 covers Arroyo Grande, Los Berros, Callender, Nipomo, Oceano, and Woodlands in San Luis Obispo County, California, one of 23 ZIP codes in the county. 172 active public water systems serve the county; 54 had an EPA violation in the past three years.

Most likely your provider

Las Ventanas Ranch CA4000815 · Community water system · Ground water
Serves 108 people Rules violated, past 3 years 0 Last sanitary survey Dec 11, 2024 Distance 2.3 mi
View system details EPA facility report

Other community water systems in San Luis Obispo County

71 systems, nearest first
SystemServesStatusRules violated, 3 yrDistance
Varian Ranch Mutual Water
 105 0 3.4 mi
Monte Sereno Mutual Benefit Water
 65 0 3.5 mi
H2o, INC
 70 1 4.8 mi
Country Hills Estates
 60 0 5.3 mi
Canyon Crest Mutual Benefit WC
 133 0 5.4 mi
Edna Valley Ranch East
 132 0 5.5 mi
Terra de Oro Water Company
 38 0 5.6 mi
Rancho Nipomo Water Company
 44 0 6.3 mi
City of Arroyo Grande Utilities Division
 17,963 1 7.1 mi
Rim Rock Water Company
 55 2 7.2 mi
Ken Mar Gardens
 84 2 8.0 mi
Halcyon Water System
 110 3 8.4 mi
Golden State Water Company-Cypress Ridge
 2,032 0 8.8 mi
Anza Vineyard Estates Mutual Water CO
 60 0 8.9 mi
City of Grover Beach Public Works Dept
 12,701 0 9.0 mi
Golden State Water Company Edna
 1,495 0 9.1 mi
Oceano Comm Services Dist.
 7,598 0 9.2 mi
Nipomo Comm Services Dist
 13,771 0 9.3 mi
Mesa Dunes Mobile Home Estates
 600 0 9.4 mi
Lopez Project
 69 1 9.9 mi
Pismo Beach Water Department
 7,944 2 10.0 mi
Laguna Negra Mutual Water Co.
 80 1 10.1 mi
Afuera de Chorro Water Company
 85 1 10.3 mi
Woodland Park Mutual Water CO
 538 2 10.7 mi
Callender Grove Mutual Water
 116 1 10.8 mi
All 72 community water systems in San Luis Obispo County
Non-community systems in San Luis Obispo County (100: schools, campgrounds, workplaces, restaurants)

These systems serve places you visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Biddle Regional County Park
 27 0 0
Lopez Recreation Area
 100 0 0
Talley Farms Labor Housing
 90 0 0
Branch Elementary School
 253 0 0
Chamisal Vineyards
Cayucos 		40 0 0
Laetitia Vineyard & Winery INC
 62 0 0
Center of Effort Winery
 75 0 0
Speedling, INC
 40 0 0
Coastal Christian School
 650 0 0
Edna Valley Vineyards
 30 0 0
Ball Tagawa Growers
 60 0 0
Greenheart Farms
 91 0 0
Pacific Dunes Ranch
 26 0 0
Santa Margarita KOA
 70 0 0
Strasbaugh, INC
 200 1 0
Noll Properties
 100 0 0
Fiero Lane Water Company, Inc.
 324 0 0
Slo Partners
 40 1 1
J M Sims Water Supply
 34 0 0
Precision Mutual Water Company
 25 1 0
Waste Connections Water CO
 35 1 0
Parsons Water Supply
 35 0 0
Zoo Med-Winterhaven
Cayucos 		80 1 0
Santa Margarita Recreation Area
 150 0 0
Sheridan Road Mutual Water Association
 38 1 1
Horizon Lane Water Supply
 32 0 0
Tmc Suburban, LLC
 25 0 0
Holdgrafer & Associates
 30 0 0
Jack Ready Imagination Park
Cayucos 		200 0 0
Tank Farm Business Park
 45 2 1
Vachell Water System
 150 1 1
141 Suburban Road Water Supply
 25 1 0
Octagon Barn Center Association
 200 0 0
Paragon Triangle Water Supply
 50 0 0
Tiger Water Supply
 1,600 0 0
Elks Lodge #322
 40 3 1
Toyota San Luis Obispo
 57 0 0
Playa Dulce
 35 0 0
Cuyama Lane Water Company
 25 3 1
Madonna Inn Water Company
 120 3 1
Sycamore Mineral Springs Resort
 200 1 1
Congregation Beth David
 25 0 0
Port San Luis Harbor District
 125 0 0
Santa Margarita Ranch Headquarters
Cayucos 		62 0 0
Granite Ridge
 50 0 0
Cerro Alto Campground
 30 1 0
Montana de Oro State Park
 990 1 0
Loading Chute
 25 1 0
Creston Elementary School
 100 0 0
Creston Country Store
 25 1 0
All non-community systems
About this data

Water systems are matched to San Luis Obispo County, the county this ZIP code lies in, nearest to the ZIP code's centre first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility. Distances are measured to the centre of the service area EPA publishes for the system or, for systems without one, to the centre of the first town EPA lists the system as serving, from Census Bureau place files.

ZIP code areas and town boundaries come from the U.S. Census Bureau's 2020 ZCTA files.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The California records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.