Foster City, California: Is the Tap Water Safe to Drink?
2026 EPA water quality data for 3 community water systems serving 36,903+ residents. See violations, PFAS results, lead test results, and safety grades — free.
Is Foster City Tap Water Safe to Drink?
Based on the latest EPA data, Foster City tap water meets all federal drinking water standards. All 3 tested systems have received a safety grade of A or B, with no active health-based violations.
Foster City Water Quality Overview
Foster City, California is served by 3 community water systems providing water to approximately 36,903 residents. These systems draw from groundwater (2), surface water purchased (1) sources. Foster City water systems have recorded 5 health-based violations in their history, though none are currently active. Including monitoring and reporting violations, there are 15 total violations on record.
Find Your Water System
Search by ZIP code to find your exact water provider and see its full EPA report.
All 3 water systems in Foster City
Looking for water quality data across the whole state? See our full California tap water safety report covering California’s EPA-regulated water systems.
Foster City Drinking Water: Frequently Asked Questions
Is Foster City, California tap water safe to drink?
Based on the latest EPA data, Foster City tap water meets all federal drinking water standards. All 3 tested systems have received a safety grade of A or B, with no active health-based violations.
How many water utilities serve Foster City, California?
3 community water systems serve Foster City, California, providing water to approximately 36,903 people. Different neighborhoods may be served by different utilities. Enter your ZIP code at the top to find your specific provider.
Does Foster City tap water have lead?
Lead in drinking water typically enters from old pipes and fixtures inside homes and buildings, not from the treatment plant. The EPA requires water systems to monitor for lead under the Lead and Copper Rule. Click any water system above to see its most recent 90th-percentile lead test results. Homes built before 1986 are most likely to have lead plumbing components.
What contaminants have been found in Foster City drinking water?
EPA violation records for Foster City water systems are listed on each utility's report page. Common regulated contaminants include disinfection byproducts (TTHMs, HAA5), coliform bacteria, nitrates, and lead. Click any utility above to see its full violation history going back 10 years.
How do I find out which water company serves my address in Foster City?
Enter your Foster City ZIP code in the search box at the top of this page. ClearWater will identify the specific water system serving your area and show you its EPA violation history, lead test results, and an overall safety grade. You can also check your water bill or your utility's annual Consumer Confidence Report (CCR).