North Castle Water District #4
EPA ID: NY5922909 · 1,225 people served · 1 ZIP code
Where compliant utilities carry no open actions, North Castle Water District #4 shows 18 active EPA violations in the federal database for a service population of approximately 1,225.
Data: EPA SDWIS Last verified: 2026-04-02
Compliance Trajectory
Worsening · Risk tier: High · 95% chance of violation in next 12 months
Violations went from 1 (2023) to 10 (2025). The pattern suggests growing compliance challenges.
Service Area Map
Coverage area for North Castle Water District #4 Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The North Castle Water District #4 serves a community with a median household income of $247,433 and an estimated 7,853 residents across its service area. Approximately 60% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
North Castle Water District #4'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 1% of homes in Westchester County, New York 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 North Castle Water District #4 compares to EPA limits
What This Means For You
Contaminant 2806 at 17 mg/L exceeds the EPA maximum of mg/L.
Contaminant 1028 at 1 mg/L exceeds the EPA maximum of mg/L.
Comparable Water Systems
Similar-sized systems in New York
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
North Castle Water District #4 (EPA ID: NY5922909) is a community water system in New York that serves approximately 1,225 people from groundwater sources.
This system serves ZIP code 10504 in Armonk.
Average Home Safety Score: C (60/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| October 1, 2024 | Contaminant 2806 | Health-based | Unresolved |
| January 1, 2024 | Contaminant 2806 | Health-based | Unresolved |
| July 1, 2023 | Contaminant 2806 | Health-based | Unresolved |
| April 1, 2023 | Contaminant 2806 | Health-based | Unresolved |
| January 1, 2023 | Contaminant 2806 | Health-based | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Contaminant 2806 | Other Violation | 17 | Yes |
| Contaminant 1028 | Other Violation | 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 |
|---|---|---|---|
| 10504 | 0.0015 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 3 (Low Risk)
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: 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 NY or modeled from parcel and building-footprint data.
- 10504 — Armonk
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for North Castle Water District #4 (NY5922909) on EPA.gov.
Frequently Asked Questions
Is North Castle Water District #4 water safe to drink?
North Castle Water District #4 has recorded 17 health-based violations in the past 5 years. While the system is required to treat water to meet federal standards, you may want to consider additional precautions such as a certified water filter.
How many people does North Castle Water District #4 serve?
North Castle Water District #4 serves approximately 1,225 people across 1 ZIP code in New York.
Where does North Castle Water District #4 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
North Castle Water District #4 (EPA ID: NY5922909) — request the latest Consumer Confidence Report or ask about specific contaminants.