Tapcensus

Water quality for ZIP code 94019

ZIP 94019 covers Half Moon Bay, El Granada, and Moss Beach in San Mateo County, California, one of 30 ZIP codes in the county. 51 active public water systems serve the county; 15 had an EPA violation in the past three years.

Most likely your provider

Coastside County Water District CA4110011 · Community water system · Surface water
Serves 19,033 people Rules violated, past 3 years 0 Last sanitary survey Jul 26, 2023 Distance 1.8 mi

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

Other community water systems in San Mateo County

35 systems, nearest first
SystemServesStatusRules violated, 3 yrDistance
Town of Hillsborough
11,766 0 6.7 mi
Mid-Peninsula Water District
31,059 0 7.2 mi
Montara Water and Sanitary District
6,088 0 7.2 mi
California Water Service San Mateo
103,536 0 7.4 mi
California Water Service San Carlos
34,801 0 8.0 mi
City of Burlingame
Burlingame
32,453 0 8.3 mi
California Water Service Bear Gulch
60,382 0 8.4 mi
City of Millbrae
Millbrae
22,795 1 9.0 mi
Estero Municipal Improvement District
36,556 0 9.8 mi
City of Redwood City
Redwood City
90,043 0 9.9 mi
North Coast County Water Dist
38,546 0 10.4 mi
City of San Bruno
San Bruno
42,631 0 10.8 mi
Westborough Water District
13,486 0 12.2 mi
Redwood Terrace Mutual
56 1 12.5 mi
Menlo Park Municipal Water
Menlo Park
22,362 0 12.9 mi
Cuesta la Honda Guild INC
863 0 13.0 mi
California Water Service-S San Francisco
62,609 0 13.3 mi
County Service Area 7
300 1 13.8 mi
O'connor Tract Co-Operative Water Co.
2,789 0 14.4 mi
Palo Alto Park Mutual Water Company
2,900 0 14.5 mi
Camp Jones Gulch
44 0 14.8 mi
Loma Mar Mutual
65 0 14.9 mi
City of East Palo Alto
East Palo Alto
29,519 0 15.0 mi
County Service Area 11
450 0 15.1 mi
Camp Loma Mar
25 2 15.1 mi
All 36 community water systems in San Mateo County
Non-community systems in San Mateo County (15: schools, campgrounds, workplaces, restaurants)

These systems serve places you visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Skylawn Memorial Park (skylawn Inc)
50 1 1
UC Elkus Ranch
34 0 0
Martins Beach Water System
49 1 0
San Gregorio Company
32 1 0
Optimists Volunteers for Youth
205 1 0
LA Honda Center
33 0 0
San Mateo County Memorial Park
1,790 0 0
Harley Farms Goat Dairy
113 0 0
Butano Girl Scout Camp
154 0 0
Csp Portola State Park
172 0 0
Butano State Park Csp
121 0 0
Pigeon Point Hostel
67 1 1
Gazos Creek Beach House
33 0 0
Costanoa Campground
33 1 0
Csp Ano Nuevo State Park
709 0 0
About this data

Water systems are matched to San Mateo 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.