City of Winlock
EPA ID: WA5397500 · 3,502 people served · 1 ZIP code
ZipCheckup's reading of EPA records for City of Winlock (WA5397500): no drinking-water violations recorded since 2021. EPA lists no violations for City of Winlock, serving 3,502 people.
Data: EPA SDWIS
Service Area Map
Coverage area for City of Winlock Source: EPA SDWIS service area boundaries.
Service area boundary
Demographics of ZIP Codes Served
The ZIP codes associated with City of Winlock have a median household income of $75,750 and about 7,276 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 50% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: On average, 40% of census tracts in the counties mapped to this service area are designated disadvantaged by the federal Climate and Economic Justice Screening Tool (CEJST, 2022 version). Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
City of Winlock's water is classified in EPA records as a groundwater source. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
Superfund Proximity Note: This service area ranks in the 70th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in Washington
System Overview
City of Winlock (EPA ID: WA5397500) is a community water system in Washington that serves approximately 3,502 people from groundwater sources.
This system serves ZIP code 98596 in Winlock.
Violation History
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| 0.0024 mg/L | No | 2023-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
Radon Risk in Service Area
1 of 1 ZIP records with known zones is in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by WA or modeled from parcel and building-footprint data.
- 98596 - Winlock
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for City of Winlock (WA5397500) on EPA.gov.
Frequently Asked Questions
Is City of Winlock water safe to drink?
The accepted 2026Q2 ECHO snapshot contains zero violation records for City of Winlock in the inclusive 2021-2026 record-year window. This is a compliance-record finding, not a guarantee about water at a specific tap.
How many people does City of Winlock serve?
City of Winlock serves approximately 3,502 people across 1 ZIP code in Washington.
Where does City of Winlock get its water?
The primary water source is groundwater.
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). City of Winlock Water Quality Report, WA. https://zipcheckup.com/water-system/wa5397500/
@misc{zipcheckup-water-system-wa5397500,
author = {{ZipCheckup}},
title = {{City of Winlock Water Quality Report, WA}},
year = {n.d.},
url = {https://zipcheckup.com/water-system/wa5397500/}
}