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Federal water data

County water report

Middlesex County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Middlesex County, New Jersey.

Water grade

C

Water score

61.7

State rank

#9

of 21

Health violations

35

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

258

36,640 recent measurements

Live streamflow

28%

Lawrence Brook at Westons Mills NJ

Water at a glance

Key Water Indicators for Middlesex County

EPA SDWIS

Safety Grade

C

Score: 61.7 / 100

EPA SDWIS

Active Violations

35

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

28% of mean

Lawrence Brook at Westons Mills NJ

EPA WQP

Monitoring Sites

258

36,640 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

C

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

61.7/100

Health violations

35

Health-based violations

Violations per 100K served

5.3

Population-normalized SDWIS rate

Data center water stress

Middlesex County has 15 facilities in the DCWSI dataset.

ByCounty's DCWSI ranks this county #59 nationally by combining its water score with mapped data center density.

DCWSIThe Data Center Water Stress Index: 60% the county's water-system stress plus 40% how concentrated data centers already are, scored 0-100. Higher means data-center density and water pressure overlap more here.

73.1

0-100 index

Facility count

15

90.3 density percentile

Discharge estimate

Not reported

EPA CWA fields where available

Water vs median

+11.7

Compared with US county median

Named operators

BarclaysDataBankDigital RealtyEquinixQuality Technology Services

Mapped facilities

  • Barclays Datacenter

    Barclays

    OSM

  • BLOOMBERG PISCATAWAY DATA CTR

    PISCATAWAY

    EPA ECHO

  • DataBank Piscataway EWR2

    DataBank

    OSM

  • Digital Realty New York EWR11

    Piscataway Township · Digital Realty

    OSM

  • Digital Realty New York EWR12

    Piscataway Township · Digital Realty

    OSM

  • Equinix

    Equinix

    OSM

9 more mapped facilities included in the county score.

See the Middlesex County data-center reportReview methodology

Data Center Water Budget Calculator

Estimate daily water use for a hypothetical facility in Middlesex County.

1 MW1,000 MW
40%100%
799K gallons/dayModerate Impact

Your facility would use 11.1% of this county's industrial water baseline — manageable but worth monitoring against drought trends.

11.1% of county industrial baseline6.37 Mgal/day remaining headroom

Based on USGS 2020 water-use data and EPA-standard cooling intensity constants. Not a substitute for site-specific water rights analysis.

Editorial analysis

Understanding Middlesex County’s Water

Drinking Water Quality Overview

EPA SDWIS

Middlesex County's drinking water earned a C grade, scoring 61.7 out of 100. Over the past five years, EPA SDWIS records 35 health-based violations — a pattern that public water utilities are required to disclose and correct.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T14:30:00.000-04:00) puts Lawrence Brook at 15.7 cfs — well below its long-term average at 28% of mean — low-flow conditions worth noting for water-dependent ecosystems. Streamflow is a leading indicator of drought stress, sediment load, and dilution capacity: low flows concentrate pollutants and warm water temperatures, stressing aquatic life and, in surface-water-dependent systems, the source water quality for treatment plants.

Monitoring Network

EPA WQP

EPA's Water Quality Portal (WQP) aggregates monitoring data from federal, state, and tribal agencies. Middlesex County has extensive coverage with 258 active monitoring sites with 36,640 recent measurements on record. Predominant monitoring categories include physical and pfas,perfluorinated alkyl substance. More monitoring sites generally indicate greater scientific attention to local water conditions — and provide the baseline data that regulators use to set future impairment listings.

Editorial advisory

What the data suggests for Middlesex County

Water Verdict

Middlesex County receives a fair water quality assessment with a grade of C and a score of 61.7 out of 100. The water supply meets baseline federal standards, but there may be periods of elevated contaminant levels or infrastructure concerns worth monitoring.

Violation Context

Middlesex County has recorded 35 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 5.3 violations per 100,000 people served, this rate is moderate and suggests recurring water quality challenges.

Consumer Guidance

Tap water in Middlesex County meets baseline standards but the compliance record shows room for improvement, with a Grade C rating. Middlesex County's drinking-water compliance score is 61.7 out of 100. The violation rate for Middlesex County is 5.3 per 100,000 people served. Residents who are immunocompromised, pregnant, or have young children may benefit from using an NSF 53-certified filter. Contacting your local utility for the current Consumer Confidence Report will confirm which specific violations were recorded and whether they have been resolved. With 258 active water-quality monitoring sites in Middlesex County, data coverage is strong. A pipeline streamflow snapshot from the Lawrence Brook gauge is also available on this page.

Regional Context

Middlesex County has better water quality than the average county in New Jersey. Its water score is 6 points higher than the state average, indicating stronger water system performance relative to neighboring counties.

Advisory text summarizes county-level public records and is not a replacement for your utility's current Consumer Confidence Report or direct local notices.

Contaminants & Resources

Key issues flagged in Middlesex County's water environment

Official EPA Resources for Middlesex County

EPA How's My Waterway

Interactive watershed health data for Middlesex County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Middlesex County

Consumer Confidence Reports (NJ)

Annual water quality reports from utilities in New Jersey

Past 5 years

Water Quality Monitoring

Monitoring Sites

258

Active in the past 5 years

Measurements Recorded

37K

36,640 total readings

Most Measured

  • Physical
  • PFAS,Perfluorinated Alkyl Substance
  • Microbiological

Categories measured most frequently

Data from the EPA Water Quality Portal (WQP), aggregating monitoring records from federal, state, and tribal sources. Each measurement represents a single sample analyzed for a specific characteristic (e.g., E. coli, pH, dissolved oxygen, nitrogen).

Live USGS Streamgage

River & Stream Conditions

Current Discharge

15.7cfs

May 14, 6:30 PM UTC

vs Long-Term Average

28%

Well below typical

Primary Streamgage

Lawrence Brook at Westons Mills NJ

USGS site
01405030
Drainage area
44.9 sq mi
Long-term mean
56.1 cfs

One representative streamgage (the one with the largest drainage area in the county). Many counties have multiple gauges; this view summarizes the primary one. The long-term mean is the full-record annual average; the percent-of-typical value compares the latest reading against that average.

Free tool

Estimate Your Water Costs

Water Cost Estimate

3

3 people  ·  ~225 gal/day

Annual Total

$558

Monthly

$47

Water Bill

$558/yr

Filter Cost

$0/yr

Safety Grade for Middlesex County:C — Moderate

Some violations or watershed impairment detected.

Estimates use the national average residential water rate ($0.0068/gal, EPA/AWWA 2023) and EPA WaterSense per-person consumption baseline (75 gal/person/day). Actual bills vary by utility, usage tier, and local infrastructure fees. For informational purposes only.

Try the full calculator →

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Frequently Asked Questions

What is the water quality in Middlesex County, New Jersey?
Middlesex County, New Jersey has a drinking-water quality grade of C with a score of 61.7/100, based on EPA SDWIS compliance data. The county has 35 health-based drinking water violations over the past 5 years. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in Middlesex County?
Middlesex County has 35 health-based drinking water violations recorded by the EPA over the past 5 years. Health-based violations indicate instances where contaminant levels exceeded EPA Maximum Contaminant Levels (MCLs). Violations may have been resolved — check with your local water utility for current status.
How much water-quality monitoring happens in Middlesex County?
EPA's Water Quality Portal records 36,640 measurements from 258 monitoring sites in Middlesex County over the past five years. The most frequently measured characteristic groups are Physical, PFAS,Perfluorinated Alkyl Substance, Microbiological. Each measurement is a single sample analyzed for one characteristic (E. coli, pH, dissolved oxygen, etc.). High monitoring density means more scientific evidence behind any reported signal — it does not by itself indicate water quality.
What's happening with rivers in Middlesex County right now?
Middlesex County's primary USGS streamgage on the Lawrence Brook has a pipeline snapshot of 15.7 cubic feet per second — 28% of the long-term mean of 56.11 cfs. This is well below typical — often a signal of drought stress on source water. For the latest gauge feed, visit waterdata.usgs.gov.
How does Middlesex County water compare to the New Jersey average?
Middlesex County's SDWIS water quality score of 61.7/100 is higher than the New Jersey state average of 55.7. The average water quality grade across New Jersey is D, based on data from 21 counties with available SDWIS data.
Is tap water safe to drink in Middlesex County?
Based on EPA SDWIS data, Middlesex County has a water quality grade of C (61.7/100). This indicates moderate compliance. Some violations have been recorded but overall standards are maintained. The grade speaks to the public water system, not the watershed — for watershed-level concerns, see the Watershed Health zone. For the most up-to-date information, contact your local water utility or review your Consumer Confidence Report (CCR).
Why does Middlesex County have so many water violations?
Middlesex County has 35 health-based drinking water violations on record from the EPA SDWIS database. A higher violation count can result from aging infrastructure, underfunded water utilities, agricultural runoff contamination, or industrial pollution. Counties with more water systems may also see more violations simply due to scale. Residents concerned about water quality should consider independent water testing and home filtration systems.
How does Middlesex County rank for water quality in New Jersey?
Middlesex County ranks #9 out of 21 counties in New Jersey by SDWIS water quality score (1 = best). With a score of 61.7/100, it falls in the middle third of counties statewide. The ranking reflects EPA SDWIS compliance only — not watershed impairment, monitoring density, or streamflow, which are tracked separately on this page.

Counties with Similar Water Quality

Mercer County

New Jersey

B

62.3

Water score

Burlington County

New Jersey

C

60.6

Water score

Ocean County

New Jersey

B

63.0

Water score

Data Sources

Drinking-water compliance data from the EPA Safe Drinking Water Information System (SDWIS) via the ECHO enforcement database. Scores reflect compliance history and health-based violation counts.

Water-quality monitoring counts from the EPA Water Quality Portal (WQP), federated USGS, EPA, and state agency sampling records over a rolling 5-year window.

Live streamflow from the USGS National Water Information System (NWIS), continuous discharge measurements from the largest-drainage gauge in each county, compared against the full-record long-term annual mean.

Disclaimer: This data is informational only. It is not health, legal, or professional advice. For concerns about your specific water supply, contact your local water utility.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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