C55/100
TONASKET WATER SYSTEM — Water Quality Report 2026
Serving 2,392 people · Washington
Water Source
Groundwater
County
—
System ID
WA5388700
Violations
18
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.66 mg/L | 1.30 mg/L | Over Limit |
Lead (90th percentile) | 0.002 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2020.
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 TONASKET WATER SYSTEM
Is TONASKET WATER SYSTEM water safe to drink?
TONASKET WATER SYSTEM water receives a grade of C (55/100), which is considered fair. 1 contaminant(s) exceed EPA legal limits and 18 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has TONASKET WATER SYSTEM detected?
2 contaminants were tested in TONASKET WATER SYSTEM's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile). 1 exceed EPA legal limits (MCLs). 2 exceed EPA health goals (MCLGs).
Does TONASKET WATER SYSTEM have any EPA violations?
Yes, TONASKET WATER SYSTEM has 18 EPA violation(s) on record, with the most recent in 2020. Violation types include MON, Other, MR. 4 are health-based violations.
How many people does TONASKET WATER SYSTEM serve?
TONASKET WATER SYSTEM serves approximately 2,392 people, Washington.
What type of water does TONASKET WATER SYSTEM provide?
TONASKET WATER SYSTEM sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WA5388700.
How does TONASKET WATER SYSTEM compare to other utilities in Washington?
TONASKET WATER SYSTEM scores 55/100 with a grade of C (fair). This score indicates room for improvement compared to other utilities. Visit our Washington state page for a full comparison of water systems.