A89/100
WILLOW COUNTY WATER DISTRICT — Water Quality Report 2026
Serving 3,797 people · California
Water Source
Purchased Surface Water
County
—
System ID
CA2310005
Violations
3
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.50 mg/L | 1.30 mg/L | Over Limit |
EPA Violation History
1
Violation (last 5yr)
1
Unresolved
0
Health-Related
TIER 3Unresolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: August 1, 2024 – August 31, 2024Rule: Total Coliform RuleEnforcement: Formal — state order issuedVerify on EPA.gov
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 WILLOW COUNTY WATER DISTRICT
Is WILLOW COUNTY WATER DISTRICT water safe to drink?
WILLOW COUNTY WATER DISTRICT water receives a grade of A (89/100), which is considered excellent. Out of 32 contaminants tested, 1 exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has WILLOW COUNTY WATER DISTRICT detected?
32 contaminants were tested in WILLOW COUNTY WATER DISTRICT's water. Notable contaminants include Copper (90th percentile). 1 exceed EPA legal limits (MCLs). 1 exceed EPA health goals (MCLGs).
Does WILLOW COUNTY WATER DISTRICT have any EPA violations?
Yes, WILLOW COUNTY WATER DISTRICT has 3 EPA violation(s) on record, with the most recent in 2024. Violation types include MON, MR, Other.
How many people does WILLOW COUNTY WATER DISTRICT serve?
WILLOW COUNTY WATER DISTRICT serves approximately 3,797 people, California.
What type of water does WILLOW COUNTY WATER DISTRICT provide?
WILLOW COUNTY WATER DISTRICT sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is CA2310005.
How does WILLOW COUNTY WATER DISTRICT compare to other utilities in California?
WILLOW COUNTY WATER DISTRICT scores 89/100 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.