Knolls of Windsor
EPA ID: MD0100041 · 1,553 people served · 9 ZIP codes
EPA data: Knolls of Windsor — zero violations, five years, 1,553 served.
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 2 (2023) to 7 (2024). The pattern suggests growing compliance challenges.
Service Area Map
Coverage area for Knolls of Windsor Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The Knolls of Windsor serves a community with a median household income of $164,457 and an estimated 193,753 residents across its service area.
🌊 Where Does Your Water Come From?
Knolls of Windsor'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 1% of homes in Montgomery County, Maryland 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. 14 detections recorded. 2 exceed federal EPA limits (4 ppt for PFOA/PFOS). 2 exceed state limits.
Comparable Water Systems
Similar-sized systems in Maryland
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
Knolls of Windsor (EPA ID: MD0100041) is a community water system in Maryland that serves approximately 1,553 people from surface water sources.
This system provides water to 9 ZIP codes across 4 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 6 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.
- 20871 — Clarksburg
- 21701 — Frederick
- 21702 — Frederick
- 21703 — Frederick
- 21704 — Frederick
- 21705 — Frederick
- 21709 — Frederick
- 21754 — Ijamsville
- 21770 — Monrovia
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Knolls of Windsor (MD0100041) on EPA.gov.
Frequently Asked Questions
Is Knolls of Windsor water safe to drink?
Based on EPA records, Knolls of Windsor has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Knolls of Windsor serve?
Knolls of Windsor serves approximately 1,553 people across 9 ZIP codes in Maryland.
Where does Knolls of Windsor get its water?
The primary water source is surface water.
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.