PlainWater
Counties → New Jersey

Mercer County, New Jersey

Water Systems
97
Population Served
323,840
Total Violations
7,431
733 health-based
PFAS Detected
6
of 7 tested

Violation Analysis

94.8%
Systems with Violations
76.6
Avg Violations per System
9.9%
Health-Based Violations

Water Source Types

GW
45 systems (46%)
SW
5 systems (5%)

PFAS Contamination

7
Systems Tested
6
PFAS Detected
85.7%
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

Mercer New Jersey water systems by violation status, EPA SDWIS records.

No violations on record (1) One or more violations (49)

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
Trenton Water Works 217,000 412 Clean
Aqua NJ - Hamilton Square 39,128 84 Detected
East Windsor Mua 25,000 92 Clean
Aqua NJ - Lawrence 8,655 346 Detected
Hightstown Water Department 5,400 129 Clean
Pennington Shop-Rite 3,663 36 Detected
Pennington W Dept 2,600 648 -
Hopewell Boro W Dept 2,035 478 -
Bent Iron Brewery 1,201 3 -
Lawrenceville School 1,200 162 -
Terhune Orchards 1,025 168 -
Corner Stone Court 940 26 -
Timberlane Middle School 901 213 -
Mercer County Correctional Center 860 308 -
Stacys Cream King 800 66 -
Washington Crossing Sp-Interpretive Ctr 720 54 -
Washington Crossing Sp Knox Grove 720 98 -
Washington Cross Sp Green Grove Pic Area 720 96 -
Washington Crossing Sp Visitors Center 720 45 -
Washington Crossing State Pk Stone Barn 720 80 -
Washington Crossing State Pk Day Use Trl 720 53 -
The Pennington School 565 113 -
Bear Tavern School 555 73 Detected
Hopewell Valley Golf Clu 548 36 -
Hamilton YMCA at Sawmill Road 498 8 -
Wildflowers 362 18 -
Washington Crossing Park Estates 356 120 -
Princeton Community Church 305 10 -
Robbinsville Twp - Newtown Village 300 14 -
Unitarian Universalist C 271 17 -
Tree Farm Village 230 58 -
Pennington Cleaners 215 30 -
Golden Nugget Antique Flea Mkt 205 28 -
Little League of Hopewell Twp 200 35 -
Princeton RD Professiona 165 6 -
Professor's Hard Cider 162 2 -
Goddard School - West Windsor 155 2 -
Kooltronic Inc 140 97 -
Titusville Marketplace 135 0 -
Pennington Montessori School 133 28 -
Saint Peter Lutheran Church 125 21 -
Offices at Pennington Point 125 117 -
Its Nutts 120 6 -
Titusville Academy Princeton 116 32 -
Patriots Crossing Restaurant 112 53 -
Princeton Child Developmnt Ins 110 63 -
Marcos Pizza 104 43 -
Hillbilly Hall, Inc. 104 68 -
Revere Restaurant 100 27 -
Mercer Professional Center @ Penn 100 39 -

Other Counties in New Jersey

Bergen County
49 systems · 1,133,521 served · 6,905 violations
Essex County
25 systems · 889,677 served · 4,186 violations
Union County
7 systems · 778,855 served · 855 violations
Ocean County
214 systems · 721,554 served · 10,195 violations
Monmouth County
285 systems · 715,264 served · 9,403 violations
Burlington County
293 systems · 674,987 served · 19,188 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Mercer County? ▼
Mercer County has 7,431 total drinking water violations across 97 water systems, of which 733 are health-based violations. 94.8% of systems have at least one violation.
How many people get water from Mercer County systems? ▼
Water systems in Mercer County serve approximately 323,840 people through 97 public water systems.
Has PFAS been detected in Mercer County water? ▼
Of 7 water systems tested for PFAS in Mercer County, 6 had PFAS detected (85.7% detection rate).
What types of water sources supply Mercer County? ▼
Water systems in Mercer 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. 9.9% of Mercer 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.