Twisp Town of
EPA ID: WA5390050 · 1,044 people served · 3 ZIP codes
A total of 1 EPA violation spanning the past five monitoring years sit on Twisp Town of's record — every finding has been officially cleared, and the supplier now holds current compliance status for its service population of approximately 1,044 people, with no outstanding enforcement of any kind.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Twisp Town of Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Twisp Town of serves a community with a median household income of $47,000 and an estimated 3,149 residents across its service area. Approximately 56% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 70% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. 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?
Twisp Town of's water is pumped from underground aquifers. 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.
About 2% of homes in Okanogan County, Washington rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How Twisp Town of compares to EPA limits
What This Means For You
Lead at 1 mg/L (action level) exceeds the EPA maximum of 0.015 mg/L (action level). Brain damage in children, kidney & blood pressure in adults. Consider reverse osmosis filtration.
Lead was detected in this water system. reverse osmosis filtration can reduce exposure.
Find a certified water filter →Comparable Water Systems
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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
TWISP TOWN OF (EPA ID: WA5390050) is a community water system in Washington that serves approximately 1,044 people from groundwater sources.
This system provides water to 3 ZIP codes across 3 communities.
Average Home Safety Score: C (56/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Lead | Inorganic | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 98856 | 0.0011 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
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
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Twisp Town of (WA5390050) on EPA.gov.
Frequently Asked Questions
Is Twisp Town of water safe to drink?
Twisp Town of has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Twisp Town of serve?
Twisp Town of serves approximately 1,044 people across 3 ZIP codes in Washington.
Where does Twisp Town of get its water?
The primary water source is groundwater.
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.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
Twisp Town of (EPA ID: WA5390050) — request the latest Consumer Confidence Report or ask about specific contaminants.