West Slope Water District
EPA ID: OR4100660 · 11,000 people served · 60 ZIP codes
For the full five-year period covered by EPA monitoring, West Slope Water District has supplied tap water to 11,000 residents with no violations of any type on record.
Data: EPA SDWIS Last verified: 2026-04-02
Compliance Trajectory
Stable · Risk tier: High · 95% chance of violation in next 12 months
Violations went from 1 (2023) to 8 (2025). Violation counts have remained relatively steady.
Service Area Map
Coverage area for West Slope Water District Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The West Slope Water District serves a community with a median household income of $86,879 and an estimated 957,108 residents across its service area. Approximately 65% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
🌊 Where Does Your Water Come From?
West Slope Water District's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
About 2% of homes in Washington County, Oregon rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 68th percentile nationally for proximity to Superfund (NPL) sites.
Infrastructure Risk
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 3 detections recorded. 3 exceed federal EPA limits (4 ppt for PFOA/PFOS).
Comparable Water Systems
Similar-sized systems in Oregon
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
West Slope Water District (EPA ID: OR4100660) is a community water system in Oregon that serves approximately 11,000 people from surface water sources.
This system provides water to 60 ZIP codes across 2 communities.
Violation History
Lead & Copper
No Lead and Copper Rule sampling data available for this water system.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
Coverage: 3 ZIP codes confirmed via EPA Community Water System Service Area Boundaries v3 plus 57 additional ZIPs inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
This system serves 60 ZIP codes:
97005 · 97201 · 97202 · 97203 · 97204 97205 · 97206 · 97207 · 97208 · 97209 97210 · 97211 · 97212 · 97213 · 97214 97215 · 97216 · 97217 · 97218 · 97219 97220 · 97221 · 97222 · 97223 · 97224 97225 · 97227 · 97228 · 97229 · 97230 97231 · 97232 · 97233 · 97236 · 97238 97239 · 97240 · 97242 · 97250 · 97252 97256 · 97258 · 97266 · 97267 · 97268 97269 · 97272 · 97280 · 97281 · 97282 97283 · 97286 · 97290 · 97291 · 97292 97293 · 97294 · 97296 · 97298 · 97299
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for West Slope Water District (OR4100660) on EPA.gov.
Frequently Asked Questions
Is West Slope Water District water safe to drink?
Based on EPA records, West Slope Water District has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does West Slope Water District serve?
West Slope Water District serves approximately 11,000 people across 60 ZIP codes in Oregon.
Where does West Slope Water District get its water?
The primary water source is surface water.
Federal UCMR5 PFAS Monitoring: Tested Clean
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were detected.
Current MCL reflects the lowest state-enforceable limit (NYS 10 ppt for PFOA/PFOS, effective August 2020). The federal final MCL of 4 ppt for PFOA/PFOS (EPA April 2024 rule) is not enforceable until April 2029. Detections above 4 ppt but below 10 ppt are below current MCL but above the future federal limit.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.