Tapcensus

Water quality for ZIP code 91361

ZIP 91361 covers Thousand Oaks, Westlake Village, and Lake Sherwood in Ventura County, California, one of 29 ZIP codes in the county. 95 active public water systems serve the county; 37 had an EPA violation in the past three years.

Most likely your provider

Ventura Cwwd No. 38 Lake Sherwood CA5610069 · Community water system · Surface water purchased
Serves 1,759 people Rules violated, past 3 years 0 Last sanitary survey Aug 28, 2025 Distance 0.5 mi

Your location is within the outer bounds of this system's EPA service area.

Other community water systems in Ventura County

67 systems, nearest first
SystemServesStatusRules violated, 3 yrDistance
Cal American Water CO
66,809 0 4.3 mi
California Water Service CO Westlake
19,544 0 4.8 mi
City of Thousand Oaks Water Department
54,770 0 5.0 mi
Cal American Yerba Buena
690 0 7.0 mi
Camrosa Water District
32,700 0 7.3 mi
Triunfo Water & Sanitation District
13,898 0 7.6 mi
Calleguas Municipal Water Dist
0 0 7.6 mi
Pleasant Valley Mutual Water CO
5,306 1 10.7 mi
Camarillo Water Dept
47,701 0 11.2 mi
Ventura Cwwd No. 1 Moorpark
35,514 0 11.5 mi
Ventura Cwwd No. 19 Somis
1,429 0 11.7 mi
Ventura Wwd No. 8 Simi Valley
94,736 0 12.3 mi
Golden State Water Company Simi Valley
45,086 0 12.3 mi
Navalair Mobile Home Park
160 1 12.4 mi
Crestview Mutual Water CO
2,079 0 12.8 mi
Naval Base Ventura County, Point Mugu
1,700 1 12.8 mi
Cal American WC las Posas Estates
2,043 0 12.8 mi
Ventura Cwwd No. 17 Bell Canyon
1,946 0 12.9 mi
Waters Road Domestic Users Group
25 0 13.3 mi
Esterina Properties
50 1 13.3 mi
Brandeis Bardin Institute
665 2 13.3 mi
Siesta Mobile Home Park
160 2 13.6 mi
Solano Verde Mutual Water CO
100 0 13.7 mi
Del Norte Mutual Water Co.
215 3 13.7 mi
United Wtr Cons Dist
0 0 14.7 mi
All 68 community water systems in Ventura County
Non-community systems in Ventura County (27: schools, campgrounds, workplaces, restaurants)

These systems serve places you visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Ventura Farms
100 0 0
Foxfield Riding School
120 0 0
The Ranch at Live Oak
82 1 1
Glass House Camarillo Cultivation, LLC
450 0 0
Laguna Vista School/oceanview School Dis
377 0 0
Bouquet Multimedia
100 0 0
GP Anacapa Foods, Llc.
50 0 0
Oxnard Pallet Company
38 1 0
Nishi Quality Flowers, Inc.
92 1 1
Rio School Dist/rio del Valle School
820 0 0
Rio Mesa High School/oxnard Uhs
2,600 1 1
Rio School Dist/ Rio Real School
550 0 0
State Ready Mix, Inc.
Ventura
25 1 1
Vulcan Materials Company Cal Mat
30 1 1
Beedy Water Company, LLC
35 0 0
Vineyard Mutual Water Company/industrial
259 0 0
Santa Clara School
39 0 0
Pyramid Flowers
30 1 0
Thomas Aquinas College
382 1 0
Lake Piru Park Uwcd
960 0 0
Dennison Park
102 1 0
Usfs Wheeler Gorge Campground
500 0 0
Smith Forks Water System
3,000 1 0
Camp Scheideck
33 1 1
Usfs Chuchupate Ranger Station
26 1 1
Channel Islands National Park
30 0 0
Santa Clara Resources
30 1 0
About this data

Water systems are matched to Ventura 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.

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.