Water Quality in Cornish Flat, NH: No Violations — Grade D
Grade D · Score 53/100 · 1 water system · Updated 2026-05-03
Cornish Flat's water has significant violations. Water testing and filtration are recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Across all available EPA tracking data for Cornish Flat, NH, the record has remained clean — 1 public water system on file, zero violations recorded, and no enforcement proceedings initiated at any point in the federal dataset.
Water Quality by ZIP Code in Cornish Flat
Water quality varies across Cornish Flat's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 03746 | D | 53 | 0 | 0 | View report → |
Water Quality Overview
Cornish Flat, New Hampshire receives a water quality grade of D with an overall score of 53 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 1 water system serving Cornish Flat. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.
What Grade D Means
A grade of D indicates significant compliance issues. Cornish Flat's water systems have accumulated violations that suggest ongoing water quality challenges. Residents should check their specific ZIP code report and consider water testing or filtration.
Lead Levels
Lead testing data for Cornish Flat is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
Radon Risk
Cornish Flat is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Cornish Flat
Cornish Flat is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 750 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
How to Check Your Water in Cornish Flat
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Cornish Flat vs. Nearby New Hampshire Cities
How Cornish Flat's water quality compares to similar cities in New Hampshire:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Cornish Flat | D | 0 | 1 | 750 |
| Cornish | C | 0 | 1 | 750 |
| Harrisville | D | 0 | 1 | 750 |
| Nelson | D | 0 | 1 | 750 |
Common Questions About Cornish Flat Water
These are the most common questions residents search for about water quality in Cornish Flat, New Hampshire:
Is Cornish Flat water hard or soft? Water hardness varies by source. Cornish Flat's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Cornish Flat tap water? Cornish Flat's water receives a grade of D (53/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Cornish Flat? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Cornish Flat vs. New Hampshire Average
Understanding how Cornish Flat compares to the broader New Hampshire average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Cornish Flat.
ZIP Codes in Cornish Flat
Cornish Flat spans 1 ZIP code. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.