A85/100
Discovery Bay Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 16,790 residents · California
What's In Discovery Bay's Tap Water?
66
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 1997.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
TOWN OF DISCOVERY BAY
Population Served
16,790
Water Source
Groundwater
System ID
CA0710009
Frequently Asked Questions About Discovery Bay Water
Is Discovery Bay tap water safe to drink?
Discovery Bay, California tap water receives a grade of A (85/100), which is considered excellent. Out of 66 contaminants tested, none exceed EPA maximum contaminant levels (MCLs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Discovery Bay's water?
66 contaminants were tested in Discovery Bay's water supply. No contaminants exceed EPA legal limits (MCLs) or health goals (MCLGs), which is a positive indicator of water quality.
Does Discovery Bay have any water quality violations?
Yes, Discovery Bay has 3 EPA violation(s) on record, with the most recent in 1997. Violation types include MCL. 3 of these are health-based violations, which are the most serious category.
Do I need a water filter in Discovery Bay?
Discovery Bay water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. All contaminants are within health goals.
Where does Discovery Bay's tap water come from?
Discovery Bay's drinking water is sourced from groundwater and supplied by TOWN OF DISCOVERY BAY. The system serves approximately 16,790 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Discovery Bay's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Discovery Bay's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Discovery Bay's water compare to other cities in California?
Discovery Bay's water quality score of 85/100 earns a grade of A, which is considered excellent. This places Discovery Bay among the better-performing water systems in California. Visit our California state page to see how all cities in the state compare.
What should I do if I'm concerned about Discovery Bay's water quality?
If you have concerns about Discovery Bay's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (TOWN OF DISCOVERY BAY) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.