D24/100
Zillah Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 3,518 residents · Washington
What's In Zillah's Tap Water?
1
Contaminants Tested
0
Exceed EPA Limits
0
Above EPA Goals
EPA Violation History
2
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 1 — URGENTResolved
Maximum Contaminant Level Violation
When: October 1, 2023 – October 31, 2023Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2022 – December 31, 2022Enforcement: 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
Water Utility Details
ZILLAH CITY OF
Population Served
3,518
Water Source
Groundwater
System ID
WA5399800
Frequently Asked Questions About Zillah Water
Is Zillah tap water safe to drink?
Zillah, Washington tap water receives a grade of D (24/100), which is considered poor. 0 contaminant(s) exceed EPA maximum contaminant levels and 44 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Zillah's water?
1 contaminants were tested in Zillah's water supply. No contaminants exceed EPA legal limits (MCLs) or health goals (MCLGs), which is a positive indicator of water quality.
Does Zillah have any water quality violations?
Yes, Zillah has 44 EPA violation(s) on record, with the most recent in 2023. Violation types include MCL, MR, MON. 8 of these are health-based violations, which are the most serious category.
Do I need a water filter in Zillah?
Zillah 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 Zillah's tap water come from?
Zillah's drinking water is sourced from groundwater and supplied by ZILLAH CITY OF. The system serves approximately 3,518 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Zillah'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. Zillah'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 Zillah's water compare to other cities in Washington?
Zillah's water quality score of 24/100 earns a grade of D, which is considered poor. This is a concerning score that suggests significant water quality issues. Visit our Washington state page to see how all cities in the state compare.
What should I do if I'm concerned about Zillah's water quality?
If you have concerns about Zillah'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 (ZILLAH CITY OF) 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.