Tapcensus

Water quality in South Monrovia Island, California

South Monrovia Island is in Los Angeles County. 271 active public water systems serve the county; 66 had an EPA violation in the past three years.

Most likely your provider

Gswc-South Arcadia CA1910212 · Community water system · Ground water
Serves 27,430 people Rules violated, past 3 years 0 Last sanitary survey Mar 26, 2026 Distance 1.9 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
Cal-Am Water Company Duarte
 24,767 0 2.0 mi
Hemlock Mutual Water Co.
 686 2 2.0 mi
City of Arcadia
Arcadia		 54,236 0 2.5 mi
Valley View Mutual Water Co.
 4,613 0 2.6 mi
Valley County Water Dist.
 68,871 0 2.7 mi
Monrovia-City, Water Dept.
Monrovia		 37,931 0 3.0 mi
Sterling Mutual Water Company
 198 2 3.2 mi
Cal-Am Water Company East Pasadena
 9,963 0 4.0 mi
EL Monte-City, Water Dept.
El Monte		 23,000 0 4.3 mi
Sierra Madre-City, Water Dept.
Sierra Madre		 11,000 0 4.4 mi
Sunny Slope Water Co.
 25,252 1 4.6 mi
Azusa Light and Water
 110,044 0 4.8 mi
Del Rio Mutual
 700 1 5.4 mi
Cal/am Water Company San Marino
 48,065 0 5.5 mi
San Gabriel County WD
 40,154 0 6.0 mi
Amarillo Mutual Water Company
 3,134 0 6.2 mi
Kinneloa Irrigation Dist.
 1,808 1 6.3 mi
San Gabriel Valley Water Co.-El Monte
 240,000 0 6.5 mi
City of Industry Waterworks Systems
La Puente		 6,151 0 6.6 mi
Suburban Water Systems-Glendora
 5,301 0 6.8 mi
Suburban Water Systems-San Jose
 170,523 0 7.1 mi
Covina-City, Water Dept.
Covina		 33,300 0 7.2 mi
Gswc-South San Gabriel
 26,451 0 7.3 mi
LA Puente Valley Cwd
 8,276 0 7.5 mi
Pasadena Water and Power
Pasadena		 165,448 0 8.2 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
Usfs-Red Box Station A-3
 25 0 0
Millard Canyon Improvement Association
 42 1 0
Young-Nak Presbyterian Church
 25 0 0
Colby Ranch-United Methodist Camp
 180 0 0
Clear Creek Outdoor Education Center
 105 0 0
Coldbrook Campground
 38 0 0
Angeles Crest Christian Camp
 112 1 0
Usfs-Chilao Main A-9
 50 0 0
Plant Water Well Rockview Dairy
South Gate 		45 0 0
Rancho los Amigos Hospital
 3,200 0 0
Usfs-Crystal Lake B-13 Water
 2,000 0 0
Usfs-Monte Cristo Camp T-4
 116 0 0
Rancho Ybarra Christian Camp
 73 0 0
Huttopia Paradise Springs
 302 1 0
Saint Andrews Abbey
 210 1 1
Usfs-Valyermo Ranger Station
 25 1 1
Camp Elk
 121 0 0
Usfs-Jackson Lake V-4
 805 0 0
Usfs-Appletree Flats V-3
 25 0 0
Angeles Shooting Ranges
 490 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
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
Agua Dulce Winery
 113 0 0
Living Springs Church
 50 0 0
Shepherd of the Hills
 80 0 0
Desert Aire Golf Course
 80 0 0
LE Chene Restaurant Water System
 100 0 0
Los Angeles World Airports
 180 0 0
Lockheed Martin Skunk Works
 135 0 0
General Atomics Aeronautical Gray Butt
 405 0 0
Northrop Grumman Corp.
 5,764 1 0
Texas Canyon Ranger Station
 30 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, nearest to South Monrovia Island 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.

Town locations and ZIP code areas come from U.S. Census Bureau 2020 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.