Tapcensus

Water quality for ZIP code 91790

ZIP 91790 covers West Covina, Valinda, Vincent, and Baldwin Park in Los Angeles County, California, one of 295 ZIP codes in the county. 271 active public water systems serve the county; 66 had an EPA violation in the past three years.

Most likely your provider

Valley County Water Dist. CA1910009 · Community water system · Ground water
Serves 68,871 people Rules violated, past 3 years 0 Distance 2.5 mi

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

View system details EPA facility report

Other community water systems in Los Angeles County

198 systems, nearest first
SystemServesStatusRules violated, 3 yrDistance
Suburban Water Systems-San Jose
 170,523 0 2.0 mi
Valley View Mutual Water Co.
 4,613 0 2.8 mi
City of Industry Waterworks Systems
La Puente		 6,151 0 3.1 mi
LA Puente Valley Cwd
 8,276 0 3.2 mi
Covina-City, Water Dept.
Covina		 33,300 0 3.5 mi
Azusa Light and Water
 110,044 0 3.7 mi
Valencia Heights Water Co.
 7,775 0 4.0 mi
Hemlock Mutual Water Co.
 686 2 4.4 mi
Sterling Mutual Water Company
 198 2 4.4 mi
Suburban Water Systems-Covina Knolls
 1,451 0 4.8 mi
Cal-Am Water Company Duarte
 24,767 0 4.9 mi
Covina Valley Water Company Wholesale
 0 0 5.0 mi
Suburban Water Systems-Glendora
 5,301 0 5.1 mi
Del Rio Mutual
 700 1 5.1 mi
Gswc-South Arcadia
 27,430 0 5.5 mi
San Gabriel Valley Water Co.-El Monte
 240,000 0 5.7 mi
EL Monte-City, Water Dept.
El Monte		 23,000 0 5.9 mi
Rowland Water District
 56,100 0 6.3 mi
Calif State Polytechnical Univ Pomona
 2,668 2 6.7 mi
Gswc-San Dimas
 56,564 0 6.8 mi
Glendora-City, Water Dept.
Glendora		 44,411 0 6.8 mi
Three Valleys Mwd
 0 0 7.0 mi
Walnut Valley Water District
 100,941 0 7.1 mi
LA Habra Heights Cwd
 5,682 0 7.4 mi
City of Arcadia
Arcadia		 54,236 0 7.4 mi
All 199 community water systems in Los Angeles County
Non-community systems in Los Angeles County (72: schools, campgrounds, workplaces, restaurants)

These systems serve places you visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Martin Marietta Southern Calif Aggregate
 51 0 0
Irwindale Brewery Yard (iby)
 300 0 0
Usfs-Chantry Flats-A16 Water
 113 0 0
Henninger Flats
 50 0 0
Usfs-Skyline Park / Mount Wilson A-4
 25 0 0
Plant Water Well Rockview Dairy
South Gate 		45 0 0
Usfs-Red Box Station A-3
 25 0 0
Millard Canyon Improvement Association
 42 1 0
Rancho los Amigos Hospital
 3,200 0 0
Coldbrook Campground
 38 0 0
Young-Nak Presbyterian Church
 25 0 0
Usfs-Crystal Lake B-13 Water
 2,000 0 0
Colby Ranch-United Methodist Camp
 180 0 0
Clear Creek Outdoor Education Center
 105 0 0
Usfs-Chilao Main A-9
 50 0 0
Angeles Crest Christian Camp
 112 1 0
Usfs-Monte Cristo Camp T-4
 116 0 0
Huttopia Paradise Springs
 302 1 0
Rancho Ybarra Christian Camp
 73 0 0
Usfs-Jackson Lake V-4
 805 0 0
Camp Elk
 121 0 0
Usfs-Appletree Flats V-3
 25 0 0
Mountain High East Ski Area
 150 0 0
Mount Kare Camp/kare Youth League
 59 0 0
Usfs-Big Pines V-2
 54 0 0
Usfs-Valyermo Ranger Station
 25 1 1
Saint Andrews Abbey
 210 1 1
Angeles Shooting Ranges
 490 0 0
1000 Trails / Soledad Canyon Preserve
 812 1 0
Acton Four Square Church
 50 0 0
Acton-Agua Dulce Lds Church
 150 0 0
Acton la North KOA
 400 0 0
Acton Conservation Camp #11
 90 4 0
Vasquez Rocks County Park
 30 0 0
Ilead Agua Dulce Charter School
 450 1 1
Agua Dulce Women's Club
 50 0 0
Lang Ranch Shopping Center
 28 0 0
Wagon Wheel Plaza
 55 1 0
Agua Dulce Water System
 493 0 0
General Atomics Aeronautical Gray Butt
 405 0 0
Desert Aire Golf Course
 80 0 0
Agua Dulce Winery
 113 0 0
Living Springs Church
 50 0 0
Shepherd of the Hills
 80 0 0
Los Angeles World Airports
 180 0 0
LE Chene Restaurant Water System
 100 0 0
Lockheed Martin Skunk Works
 135 0 0
Northrop Grumman Corp.
 5,764 1 0
Antelope Valley Indian Museum State Park
 506 0 0
Lancaster National Soccer Center
Lancaster 		500 0 0
All non-community systems
About this data

Water systems are matched to Los Angeles 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.