A97/100
SANTA ROSA, CITY OF — Water Quality Report 2026
Serving 175,396 people · California
Water Source
Groundwater
County
—
System ID
CA4910009
Violations
0
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 2.40 mg/L | 1.30 mg/L | Over Limit |
EPA Violation History
No violations in the past 5 years
This system has a clean compliance history.
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
Frequently Asked Questions About SANTA ROSA, CITY OF
Is SANTA ROSA, CITY OF water safe to drink?
SANTA ROSA, CITY OF water receives a grade of A (97/100), which is considered excellent. Out of 74 contaminants tested, 1 exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has SANTA ROSA, CITY OF detected?
74 contaminants were tested in SANTA ROSA, CITY OF's water. Notable contaminants include Copper (90th percentile). 1 exceed EPA legal limits (MCLs). 1 exceed EPA health goals (MCLGs).
Does SANTA ROSA, CITY OF have any EPA violations?
No, SANTA ROSA, CITY OF has zero EPA violations on record. This indicates consistent compliance with federal drinking water standards.
How many people does SANTA ROSA, CITY OF serve?
SANTA ROSA, CITY OF serves approximately 175,396 people, California. The system provides water to 1 community: Santa Rosa.
What type of water does SANTA ROSA, CITY OF provide?
SANTA ROSA, CITY OF sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is CA4910009.
How does SANTA ROSA, CITY OF compare to other utilities in California?
SANTA ROSA, CITY OF scores 97/100 with a grade of A (excellent). This places it among the higher-performing utilities in the state. Visit our California state page for a full comparison of water systems.