C59/100
YAK CO - TERRACE HEIGHTS — Water Quality Report 2026
Serving 8,410 people · Washington
Water Source
Groundwater
County
—
System ID
WA5306029
Violations
33
Contaminant Test Results
EPA Violation History
2
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 1 — URGENTResolved
Maximum Contaminant Level Violation
When: August 1, 2023 – August 31, 2023Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: October 1, 2022 – October 31, 2022Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
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 YAK CO - TERRACE HEIGHTS
Is YAK CO - TERRACE HEIGHTS water safe to drink?
YAK CO - TERRACE HEIGHTS water receives a grade of C (59/100), which is considered fair. 0 contaminant(s) exceed EPA legal limits and 33 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has YAK CO - TERRACE HEIGHTS detected?
31 contaminants were tested in YAK CO - TERRACE HEIGHTS's water. No contaminants exceed EPA legal limits or health goals, indicating good water quality management.
Does YAK CO - TERRACE HEIGHTS have any EPA violations?
Yes, YAK CO - TERRACE HEIGHTS has 33 EPA violation(s) on record, with the most recent in 2023. Violation types include MCL, MON, Other. 2 are health-based violations.
How many people does YAK CO - TERRACE HEIGHTS serve?
YAK CO - TERRACE HEIGHTS serves approximately 8,410 people, Washington.
What type of water does YAK CO - TERRACE HEIGHTS provide?
YAK CO - TERRACE HEIGHTS sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WA5306029.
How does YAK CO - TERRACE HEIGHTS compare to other utilities in Washington?
YAK CO - TERRACE HEIGHTS scores 59/100 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.