PlainWater
Counties → New Hampshire

Merrimack County, New Hampshire

Water Systems
247
Population Served
124,101
Total Violations
14,635
3,144 health-based
PFAS Detected
2
of 7 tested

Violation Analysis

92.7%
Systems with Violations
59.3
Avg Violations per System
21.5%
Health-Based Violations

Water Source Types

GW
45 systems (18%)
SW
5 systems (2%)

PFAS Contamination

7
Systems Tested
2
PFAS Detected
28.6%
Detection Rate

PFAS (per- and polyfluoroalkyl substances) are persistent chemicals found in drinking water. The EPA has set enforceable limits for several PFAS compounds under UCMR5 monitoring.

Compliance Snapshot

Merrimack New Hampshire water systems by violation status, EPA SDWIS records.

No violations on record (3) One or more violations (47)

Violation history is cumulative, many flagged systems have already returned to compliance. Detail pages show per-system context.

Water Systems

System Name Population Violations PFAS
Concord Water Dept 44,215 4 Clean
Franklin Water Works 7,000 367 Clean
Pembroke Water Works 5,200 146 Detected
Central Hooksett Water Pct 4,650 30 Detected
Penacook Boscawen Water Pct 3,800 50 Clean
Cogswell Springs Water Works 3,000 42 -
Hooksett Village Water Pct 3,000 60 -
New London Springfield Water 2,750 285 Clean
Tilton Northfield Water Dist 2,500 379 -
NH Motor Speedway 2,300 22 -
Pittsfield Aqueduct 1,630 376 -
Contoocook Village Pct 1,600 93 -
Canterbury Rest Area 1,505 12 -
Sutton Rest Area 1,160 0 -
Rapid Refill 135 999 5 -
Wendys/Dunkin Donuts 999 8 -
Mt Sunapee Ski Area/Main Lodge 950 7 -
Mt Sunapee Ski Area/Summit 950 16 -
Bear View Crossing 800 25 -
Epsom Village Water Distict 800 10 -
McDonalds Restaurant 700 12 -
Warner Village Water Dist 660 61 -
Andover Village Dist 650 264 -
Kearsarge Regional High Sch 650 16 -
Bow High School 645 40 -
Bow Memorial School 615 110 -
Allenstown Community School 608 0 -
Ragged Mountain Ski/Golf 600 48 -
Dunkin Donuts 600 9 -
Kearsarge Regional Middle Sch 550 24 -
Camp Kenwood and Evergreen 534 28 -
Bow Elementary School 522 145 -
Chucksters 500 0 -
Elm Brook Park 500 8 -
Dunkin Donuts 500 19 -
Mt Sunapee State Pk/Bath House 500 10 -
Cascade Campground/Lower 475 97 -
Sandy Beach RV Resort I 463 37 -
Spacious Skies French Pond 400 43 -
Circle 9 Ranch Campground 395 115 -
Catamount Hill 383 94 -
Cozy Pond Camping Resort/West 375 60 -
Freedom Hill/Pine Ridge Est 370 190 -
Kings Towne MHP 350 63 -
Hill Water Works 350 60 -
Loudon Elementary Sch 321 7 -
Pitco Frialator 311 20 -
Chen Yang Li Restaurant 300 138 -
Chucksters 300 28 -
Shaker RD Sch & Childcare Ctr 300 14 -

Other Counties in New Hampshire

Hillsborough County
280 systems · 336,342 served · 17,880 violations
Rockingham County
559 systems · 273,232 served · 32,389 violations
Strafford County
132 systems · 107,387 served · 8,921 violations
Grafton County
269 systems · 101,638 served · 20,540 violations
Carroll County
363 systems · 80,560 served · 21,120 violations
Belknap County
255 systems · 74,926 served · 16,111 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Merrimack County? ▼
Merrimack County has 14,635 total drinking water violations across 247 water systems, of which 3,144 are health-based violations. 92.7% of systems have at least one violation.
How many people get water from Merrimack County systems? ▼
Water systems in Merrimack County serve approximately 124,101 people through 247 public water systems.
Has PFAS been detected in Merrimack County water? ▼
Of 7 water systems tested for PFAS in Merrimack County, 2 had PFAS detected (28.6% detection rate).
What types of water sources supply Merrimack County? ▼
Water systems in Merrimack County use GW (45 systems), SW (5 systems) as their primary water sources.
Are health-based violations serious? ▼
Health-based violations indicate that drinking water exceeded Maximum Contaminant Levels (MCLs) set by the EPA or failed treatment technique requirements. 21.5% of Merrimack County's violations are health-based. Not all violations indicate immediate health risk, but they require corrective action.
Data Sources & Methodology

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). PFAS testing data from the UCMR5 monitoring program. SDWIS tracks all public water systems regulated under the Safe Drinking Water Act.

Violations are categorized as health-based (Maximum Contaminant Level exceedances, treatment technique failures) or monitoring/reporting violations. Not all violations indicate an immediate health risk.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.