Hopkinton Water Department
EPA ID: MA2139000 · 12,586 people served · 2 ZIP codes
Five-year compliance data for Hopkinton Water Department includes 1 violation the EPA has not yet marked resolved — those open findings are part of the utility's current enforcement profile, covering a service population of approximately 12,586 residents across the area it supplies.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Hopkinton Water Department Source: EPA SDWIS service area boundaries.
Service area boundary — Grade D
Service Area Demographics
The Hopkinton Water Department serves a community with a median household income of $204,418 and an estimated 19,050 residents across its service area. Approximately 44% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Hopkinton Water Department'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 Middlesex County, Massachusetts 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 80th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Detected Contaminants
How Hopkinton Water Department compares to EPA limits
What This Means For You
Contaminant 1039 at 2 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 1 mg/L exceeds the EPA maximum of mg/L.
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 5 detections recorded. 1 exceeds federal EPA limits (4 ppt for PFOA/PFOS).
Comparable Water Systems
Similar-sized systems in Massachusetts
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
Hopkinton Water Department (EPA ID: MA2139000) is a community water system in Massachusetts that serves approximately 12,586 people from groundwater sources.
This system provides water to 2 ZIP codes across 2 communities.
Average Home Safety Score: D (51/100)
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 |
|---|---|---|---|
| July 1, 2025 | Contaminant 1039 | Monitoring | Unresolved |
| July 1, 2023 | Contaminant 1039 | Monitoring | Resolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Contaminant 1039 | Other Violation | 2 | No |
| Stage 1 DBP Rule | Treatment Failure | 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 |
|---|---|---|---|
| 01748 | 0.0074 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
Coverage: 1 ZIP code confirmed via EPA Community Water System Service Area Boundaries v3 plus 1 additional ZIP inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Hopkinton Water Department (MA2139000) on EPA.gov.
Frequently Asked Questions
Is Hopkinton Water Department water safe to drink?
Hopkinton Water Department has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Hopkinton Water Department serve?
Hopkinton Water Department serves approximately 12,586 people across 2 ZIP codes in Massachusetts.
Where does Hopkinton Water Department get its water?
The primary water source is groundwater.
Federal UCMR5 PFAS Monitoring: Detected
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). PFAS compounds were detected below the current state-enforceable MCL.
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
Utility-reported lead service line presence and tap-sample lead level under federal LCRI requirements:
Below federal action level (0.015 mg/L)
MassDEP reports utility-level presence flag and tap-sampling without per-line breakdown. Customers should inquire with the utility about service line material at a specific address.
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: MassDEP LCRR Service Line Inventory · Submitted 2024
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
Hopkinton Water Department (EPA ID: MA2139000) — request the latest Consumer Confidence Report or ask about specific contaminants.