WaterVerge

Is East Windsor Twp.-1101, NJ Tap Water Safe to Drink?

Graded A-, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

25K residents served 1 water system PWSID: NJ1101002
Overall Score
87 / 100
Violations
3 active
Last Updated
May 2026
Source
Groundwater
#39 of 435 in New Jersey Top 27% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
87/100
waterverge.com
A- 87/100

East Windsor Twp.-1101, NJ — Water Quality Report

East Windsor Twp.-1101's drinking water received a grade of A- (87 out of 100), indicating good water quality. The city's 1 water system serves approximately 25,000 residents using groundwater.

Lead levels were measured at 1.6 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 41 violations on record, including 1 health-based violation. 3 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about East Windsor Twp.-1101's water

East Windsor Twp.-1101 ranks #39 out of 435 cities in New Jersey for water quality, placing it one of the best in the state.

East Windsor Twp.-1101 relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.09 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

Quality Breakdown

Water quality score

See methodology →
87 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
38.4/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 1.6 ppb (90th percentile).
Contaminants
15.7/20
B
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is East Windsor Twp.-1101, NJ water safe to drink?

Concerns Identified

East Windsor Twp.-1101's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 25,000 residents using groundwater (wells).

3
Active Violations
1.6 ppb
Lead (90th %ile)
1 compound
PFAS Detected
10 events
Disaster History

Recent water quality updates for East Windsor Twp.-1101

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into East Windsor Twp.-1101's water quality assessment. Grade: A- (87/100).

Violation
1 drinking water violation recorded

Contaminants: E. COLI.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Gross Alpha, Excl. Radon and U.

Disaster
REMNANTS OF HURRICANE IDA

Federal disaster declaration (FEMA DR-4614). Hurricane event — may have impacted local water infrastructure.

Disaster
REMNANTS OF HURRICANE IDA

Federal disaster declaration (FEMA DR-3573). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for East Windsor Twp.-1101's water supply.

Lead Within Limits
Detected: 1.6 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 25.1000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

East Windsor Twp.-1101's water system has 41 total violations on record, including 1 health-based violation. 3 remain unresolved. 2 violations were issued in the last 5 years.

MRMCL
Most recent violations:
Jul 2024 E. COLI Open
Apr 2024 Gross Alpha, Excl. Radon and U Resolved
Jan 2020 Selenium Resolved
Jan 2020 Cadmium Resolved
Jan 2020 Chromium Resolved

Flood & environmental risk

Mercer County has experienced 10 federally declared disasters since 1975. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Stony Brook At Princeton, Millstone River At Carnegie Lake At Princeton, Delaware And Raritan Canal At Port Mercer, Delaware And Raritan Canal At Kingston, Assunpink Creek Near Clarksville.

REMNANTS OF HURRICANE IDA
Hurricane FEMA DR-4614
REMNANTS OF HURRICANE IDA
Hurricane FEMA DR-3573
HURRICANE SANDY
Hurricane FEMA DR-4086

Where does East Windsor Twp.-1101's water come from?

East Windsor Twp.-1101's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 25,000 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Stony Brook At Princeton (river), Millstone River At Carnegie Lake At Princeton (river), Delaware And Raritan Canal At Port Mercer (stream), Delaware And Raritan Canal At Kingston (stream), Assunpink Creek Near Clarksville (river).

What East Windsor Twp.-1101 residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in East Windsor Twp.-1101's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

East Windsor Twp.-1101's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
1.6 ppb
EPA Action Level: 15 ppb · 11% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
25.1000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.8 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 1.2 µg/LHAA9: 1.4 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.09 µg/L
CA MCL (no federal MCL): 10 µg/L · 1% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
106.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 7% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Elevated
0.32 µg/L
EPA Health Advisory: 0.35 µg/L · 92% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
17.7 µg/L
EPA Secondary MCL: 50 µg/L · 35% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.48 µg/L
EPA Short-term HA: 21 µg/L · 2% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
128.0 µg/L
EPA Lifetime HA: 210 µg/L · 61% of limit
DetectedUCMR 3 Data
Cobalt
Inorganic
Detected
11.63 µg/L
No federal limit: N/A µg/L · 50% of limit
DetectedNo federal MCLUCMR 3 Data
Lithium
Inorganic
Detected
25.1 µg/L
State screening level: 60 µg/L · 42% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

41
Total violations
1
Health-based
3
Active / unresolved
Jul 2024
Most recent violation
Compliance Record

Violations & advisories

41 Total
3 Active
1 Health-based
38 Resolved
Violations by category
Volatile Organic Chemicals
21
Inorganic Chemicals
9
Stage 1 Disinfectants and Disinfection Byproducts Rule
5
Nitrate Rule
2
Ground Water Rule
1
Jul 2024 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2005 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Apr 2024 Resolved
Gross Alpha, Excl. Radon and U
Max Contaminant Level
Health-Based Health Resolved Jun 2024
Jan 2020 Resolved
Selenium
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Cadmium
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Chromium
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Beryllium, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Nickel
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Antimony, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Barium
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Thallium, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2017 Resolved
CYANIDE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2019
Oct 2015 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Oct 2014 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Jan 2014 Resolved
o-Dichlorobenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Jan 2014 Resolved
p-Dichlorobenzene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Jan 2014 Resolved
Vinyl chloride
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Jan 2014 Resolved
1,1,1-Trichloroethane
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Jan 2014 Resolved
Carbon tetrachloride
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2014
Showing 20 of 41 violations
Environmental Risk

Drought conditions

D1 — moderate drought

Mercer County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

5.6%
Months in D2+ (last 30y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

10
Declared disasters
Sep 2021
Most recent
Hurricane
Most common type

Mercer County has experienced 10 federally declared disasters since 1975. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2021
REMNANTS OF HURRICANE IDA
Hurricane FEMA #4614
Sep 2021
REMNANTS OF HURRICANE IDA
Hurricane FEMA #3573
Oct 2012
HURRICANE SANDY
Hurricane FEMA #4086
Oct 2012
HURRICANE SANDY
Hurricane FEMA #3354
Aug 2011
HURRICANE IRENE
Hurricane FEMA #4021
Aug 2011
HURRICANE IRENE
Hurricane FEMA #3332

Recommended water filters

Based on contaminants detected in East Windsor Twp.-1101's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.6 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 25.100 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.9 ppb from 1992 (4.5 ppb) to 2024 (1.6 ppb).
Contaminant Rankings

See how East Windsor Twp.-1101 compares by contaminant

Explore where East Windsor Twp.-1101 ranks among all New Jersey cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
25,000
Water Systems
1
Water Source

Where East Windsor Twp.-1101's water comes from

Groundwater

East Windsor Twp.-1101's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 25,000 people through 1 water system.

Local Hydrology

Water bodies near East Windsor Twp.-1101

East Windsor Twp.-1101 is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Stony Brook At Princeton
river
Millstone River At Carnegie Lake At Princeton
river
Delaware And Raritan Canal At Port Mercer
stream
Delaware And Raritan Canal At Kingston
stream
Assunpink Creek Near Clarksville
river
Infrastructure

Water systems serving East Windsor Twp.-1101

System Name PWSID Population Source
EAST WINDSOR MUA NJ1101002 25,000 GW
Regional Comparison

How East Windsor Twp.-1101 compares

Full New Jersey rankings →

East Windsor Twp.-1101's score of 87/100 is above the average of 63/100 among major New Jersey cities. It outscores 10 of 10 nearby cities.

East Windsor Twp.-1101 (this city)
87
New Jersey avg
63
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Frequently asked questions

Is East Windsor Twp.-1101, NJ tap water safe to drink?

East Windsor Twp.-1101's water quality earned a grade of A- (87/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #39 out of 435 cities tested in New Jersey.

What contaminants are in East Windsor Twp.-1101's water?

Lead was measured at 1.6 ppb (90th percentile). 1 PFAS compound was detected. 41 violations are on record.

How is East Windsor Twp.-1101's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in East Windsor Twp.-1101?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does East Windsor Twp.-1101's water come from?

East Windsor Twp.-1101's water is sourced from Groundwater. The city has 1 water system serving approximately 25,000 residents.

What health violations has East Windsor Twp.-1101's water system had?

East Windsor Twp.-1101 has 1 health-based violation on record. The most recent violation was recorded in July 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

Is East Windsor Twp.-1101's groundwater at risk of contamination?

East Windsor Twp.-1101 uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 41 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does East Windsor Twp.-1101's water compare to other cities?

East Windsor Twp.-1101 ranks #39 out of 435 cities in New Jersey (better than 91% of state cities) and #4295 out of 15744 cities nationally (73th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.