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WaterSafeCheck

ZIP Code 03242 Water Quality Report

Henniker, NH · Merrimack County County

Safety Score
D

Water Safety Grade

Poor — Multiple violations recorded

Health Violations

1

Total Violations

1

Lead Risk

Very High

Contaminants

1

About Tap Water in ZIP Code 03242

Tap water in ZIP code 03242 (Henniker, NH) has received a D grade (score: 54/100) — below average for the nation. Cogswell Springs Water Works has recorded notable violations with EPA Safe Drinking Water Act regulations. Residents may want to consider additional filtration and review their annual Consumer Confidence Report.

Water System

Cogswell Springs Water Works

EPA ID: NH1121010

Water Source

Ground Water

Population Served

3,000 residents

County

Merrimack County County, New Hampshire

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Lead Levels in ZIP 03242

EPA action level: 15 ppb | Public health goal: 0 ppb

Lead Level: 23.0 ppb — EXCEEDS EPA Action Level

The 90th percentile lead level in 03242 is 23.0 ppb, which EXCEEDS the EPA action level of 15 ppb. This is a serious concern. The water utility is legally required to notify residents, identify the source of contamination, and take corrective action. Do not give this water to infants, children, or pregnant women without first passing it through a certified NSF/ANSI 53 water filter. Contact Cogswell Springs Water Works immediately for current guidance, or call the EPA Safe Drinking Water Hotline at 1-800-426-4791.

Lead exposure risk in 03242 is rated Very High. EPA models estimate a 84% probability of lead exposure risk in this ZIP code based on housing age, infrastructure age, and water system data. This is among the highest risk categories nationally, often associated with heavily aging infrastructure and pre-1986 construction. Do not give unfiltered tap water to children under 6 or pregnant women. Consider getting your home's plumbing tested for lead solder and fixtures.

Lead Level (90th percentile)
23.00 ppb (0.023 mg/L)
Lead Exposure Risk Rating
Very High
Lead Exposure Probability

EPA model estimate based on housing age and infrastructure

84%
Note: Lead levels above are the 90th percentile from EPA monitoring — meaning 90% of samples were at or below this level. Even "undetected" tap water lead doesn't account for lead leaching from home plumbing. If your home was built before 1986, individual tap testing is recommended.
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Violation History

Past 5 years — EPA SDWIS data

Cogswell Springs Water Works has recorded 1 health-based violation in the past 5 years. A single health violation means the water exceeded an EPA maximum contaminant level (MCL) at some point. Most water systems resolve these quickly, but residents should review the Consumer Confidence Report for details. 1 violation is currently unresolved — meaning the issue has not yet been formally corrected in EPA records. This is a serious concern that residents should follow up on with their water utility.

Total Violations (5 yr)
1
Health-Based Violations
1
Unresolved Violations
1
Boil Water Advisories
0
Compliance Risk
High

Regulatory compliance risk is rated High. Cogswell Springs Water Works has a pattern of compliance issues that goes beyond isolated incidents. Residents should stay informed via their utility's Consumer Confidence Report.

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Contaminants Detected

Contaminants with health-based violations on record

EPA records identify 1 contaminant associated with health-based violations in ZIP code 03242: Nickel. These contaminants exceeded the Maximum Contaminant Levels (MCLs) established by the EPA under the Safe Drinking Water Act at some point in the 5-year monitoring period. The presence of these violations does not necessarily mean water is currently unsafe — water systems are often required to increase monitoring and treatment when violations occur. Review the annual Consumer Confidence Report for the most current status.

Nickel

⚖ Enforcement Actions

4 enforcement actions have been issued against Cogswell Springs Water Works — a high number that reflects sustained compliance struggles. Enforcement actions escalate from administrative orders to financial penalties when utilities repeatedly fail to meet safe drinking water standards.
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Water Source & Environmental Factors

Ground Water

This system draws water from underground aquifers. Groundwater is naturally filtered through soil and rock, but can still contain naturally occurring minerals like arsenic, radium, or nitrates.

Water Source Type
Ground Water
EPA Radon Zone

Moderate potential

Zone 2
Annual Flood Risk Cost

Estimated annual flood-related costs per property

$0
Energy Burden

% of household income spent on energy — indicator of older infrastructure

3.16%

EPA Radon Zone 2 — moderate radon potential. The EPA recommends testing your home regardless of zone designation.

🛡 What Should You Do? — ZIP 03242 Recommendations

  • 🚨 Install a certified NSF/ANSI 53 or 58 (reverse osmosis) filter immediately for drinking and cooking
  • 🚨 Do not give unfiltered water to children, pregnant women, or immunocompromised individuals
  • 🚨 Contact Cogswell Springs Water Works to request the current violation status and corrective action plan
  • 🚨 Report concerns to your state environmental agency or call the EPA hotline: 1-800-426-4791
  • 🚨 Consider having your home's tap water independently tested by a certified lab

Frequently Asked Questions — ZIP 03242 Water Quality

Is tap water safe to drink in ZIP code 03242?+
Tap water in 03242 has a below-average water quality grade of D. While it is treated, there have been notable compliance issues. We strongly recommend using a certified NSF/ANSI 53 water filter for drinking and cooking, especially for vulnerable populations.
What is the lead level in 03242 tap water?+
The 90th percentile lead level in 03242 is 23.0 ppb (parts per billion). The EPA action level is 15 ppb. This exceeds the EPA action level — use a certified lead-reducing water filter.
Who provides tap water to 03242?+
Tap water in ZIP code 03242 is provided by Cogswell Springs Water Works (EPA ID: NH1121010). This system serves approximately 3,000 residents. You can contact them directly for Consumer Confidence Reports, current advisories, and billing information.
What is the water source for 03242?+
ZIP code 03242 is served by ground water. Groundwater systems draw from underground aquifers. While naturally filtered, groundwater can still contain naturally occurring contaminants such as arsenic, radium, or nitrates at elevated levels in some regions.
Does 03242 have any active water quality violations?+
Yes — there are currently 1 unresolved violation on record for this water system. Unresolved violations indicate issues that have not yet been formally corrected in EPA tracking systems. Contact Cogswell Springs Water Works for the latest update.
How do I get a copy of my water quality report for 03242?+
Your water utility — Cogswell Springs Water Works — is required by law to send you an annual Consumer Confidence Report (CCR) by July 1 each year. You can also request it directly from the utility or find it online by searching "Cogswell Springs Water Works Consumer Confidence Report." The EPA's ECHO database also has historical compliance data.
What water filter should I use in 03242?+
The right filter depends on what contaminants are present. For lead, look for a filter certified to NSF/ANSI Standard 53. For chlorine byproducts (like THMs), NSF/ANSI 42 filters work well. For a broad range of contaminants including PFAS, look for NSF/ANSI 58 (reverse osmosis) systems. For ZIP code 03242, with detected contaminants including Nickel, a multi-stage filter or reverse osmosis system is recommended.
Is 03242 tap water safe for babies and infants?+
Infants are especially vulnerable to lead, nitrates, and microbial contaminants in drinking water. Given the detected lead level of 23.0 ppb in 03242, we recommend using a certified NSF/ANSI 53 water filter or certified bottled water for preparing infant formula. Always consult your pediatrician for guidance specific to your child's health.

Data Sources & Methodology

Water quality data for ZIP code 03242 is compiled from the EPA Safe Drinking Water Information System (SDWIS), EPA ECHO enforcement database, UCMR5 unregulated contaminant monitoring, and Consumer Confidence Reports filed by Cogswell Springs Water Works. Safety scores are composite metrics derived from violation history, lead levels, enforcement actions, and infrastructure risk indicators. Data reflects a 5-year monitoring window. Last dataset update: 2024. View EPA source data →