A98/100
Granite Bay Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 29,598 residents · California
What's In Granite Bay's Tap Water?
69
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 1989.
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
SAN JUAN WATER DISTRICT
Population Served
29,598
Water Source
Surface Water
System ID
CA3410021
Frequently Asked Questions About Granite Bay Water
Is Granite Bay tap water safe to drink?
Granite Bay, California tap water receives a grade of A (98/100), which is considered excellent. Out of 69 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 Granite Bay's water?
69 contaminants were tested in Granite Bay's water supply. No contaminants exceed EPA legal limits (MCLs) or health goals (MCLGs), which is a positive indicator of water quality.
Does Granite Bay have any water quality violations?
Yes, Granite Bay has 2 EPA violation(s) on record, with the most recent in 1989. Violation types include Other. None of these are classified as health-based violations.
Do I need a water filter in Granite Bay?
Granite 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 Granite Bay's tap water come from?
Granite Bay's drinking water is sourced from surface water and supplied by SAN JUAN WATER DISTRICT. The system serves approximately 29,598 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Granite 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. Granite 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 Granite Bay's water compare to other cities in California?
Granite Bay's water quality score of 98/100 earns a grade of A, which is considered excellent. This places Granite 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 Granite Bay's water quality?
If you have concerns about Granite 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 (SAN JUAN WATER DISTRICT) 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.