County water report

Onondaga County Water Report

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

Water grade

Water score

54.0

State rank

#13

of 57

Health violations

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

5,594 recent measurements

Live streamflow

219%

SENECA RIVER NEAR BALDWINSVILLE NY

Water at a glance

Key Water Indicators for Onondaga County

EPA SDWIS

Safety Grade

Score: 54.0 / 100

EPA SDWIS

Active Violations

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

219% of mean

SENECA RIVER NEAR BALDWINSVILLE NY

EPA WQP

Monitoring Sites

5,594 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

54.0/100

Health violations

Health-based violations

Violations per 100K served

11.2

Population-normalized SDWIS rate

Data center water stress

Onondaga County has 1 facility in the DCWSI dataset.

ByCounty's DCWSI ranks this county #1444 nationally by combining its water score with mapped data center density.

DCWSI

32.4

0-100 index

Facility count

0.0 density percentile

Discharge estimate

Not reported

EPA CWA fields where available

Water vs median

+4.0

Compared with US county median

Named operators

Syracuse University

Mapped facilities

SU Green Data Center
Onondaga · Syracuse University
OSM

See the Onondaga County data-center report Review methodology

Data Center Water Budget Calculator

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

Facility size: 100 MW

1 MW1,000 MW

Cooling type

Utilization: 70%

40%100%

799K gallons/dayHigh Impact

Your facility would use 22.4% of this county's industrial water baseline. Verify water rights and long-term drought projections before committing.

22.4% of county industrial baseline2.77 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 Onondaga County’s Water

Drinking Water Quality Overview

EPA SDWIS

Onondaga County's drinking water earned a C grade, scoring 54.0 out of 100. Over the past five years, EPA SDWIS records 68 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 2026-05-14T13:15:00.000-05:00) puts SENECA RIVER at 7.7k cfs — running significantly above its long-term average at 219% of mean flow. 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. Onondaga County has moderate coverage with 35 active monitoring sites with 5,594 recent measurements on record. Predominant monitoring categories include physical and organics, pesticide. 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 Onondaga County

Water Verdict

Onondaga County receives a below-average water quality assessment with a grade of C and a score of 54.0 out of 100. Residents should review their utility's Consumer Confidence Report and may want to consider additional water filtration for drinking.

Violation Context

Onondaga County has recorded 68 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 11.2 violations per 100,000 people served, this rate is high and signals significant water quality management issues.

Consumer Guidance

Tap water in Onondaga County meets baseline standards but the compliance record shows room for improvement, with a Grade C rating. Onondaga County's drinking-water compliance score is 54.0 out of 100. The violation rate for Onondaga County is 11.2 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 35 active water-quality monitoring sites in Onondaga County, data coverage is strong. A pipeline streamflow snapshot from the SENECA RIVER gauge is also available on this page.

Regional Context

Onondaga County has better water quality than the average county in New York. Its water score is 13.9 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 Onondaga County's water environment

Official EPA Resources for Onondaga County

EPA How's My Waterway

Interactive watershed health data for Onondaga County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Onondaga County

Consumer Confidence Reports (NY)

Annual water quality reports from utilities in New York

Past 5 years

Water Quality Monitoring

Monitoring Sites

Active in the past 5 years

Measurements Recorded

5.6K

5,594 total readings

Most Measured

Physical
Organics, Pesticide
Organics, Other

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

7,690cfs

May 14, 6:15 PM UTC

vs Long-Term Average

219%

Well above typical

Primary Streamgage

SENECA RIVER NEAR BALDWINSVILLE NY

USGS site: 04237496
Drainage area: 3,130 sq mi
Long-term mean: 3,505 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

Household size

3 people · ~225 gal/day

Filter type

Annual Total

$558

Monthly

$47

Water Bill

$558/yr

Filter Cost

$0/yr

Safety Grade for Onondaga County:D — Poor

Elevated violations or significant watershed impairment.

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 Onondaga County, New York?

Onondaga County, New York has a drinking-water quality grade of C with a score of 54.0/100, based on EPA SDWIS compliance data. The county has 68 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 Onondaga County?

Onondaga County has 68 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 Onondaga County?

EPA's Water Quality Portal records 5,594 measurements from 35 monitoring sites in Onondaga County over the past five years. The most frequently measured characteristic groups are Physical, Organics, Pesticide, Organics, Other. 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 Onondaga County right now?

Onondaga County's primary USGS streamgage on the SENECA RIVER has a pipeline snapshot of 7,690 cubic feet per second — 219% of the long-term mean of 3,505.16 cfs. This is well above typical — often a signal of recent precipitation or storm runoff. For the latest gauge feed, visit waterdata.usgs.gov.

How does Onondaga County water compare to the New York average?

Onondaga County's SDWIS water quality score of 54.0/100 is higher than the New York state average of 40.1. The average water quality grade across New York is D, based on data from 57 counties with available SDWIS data.

Is tap water safe to drink in Onondaga County?

Based on EPA SDWIS data, Onondaga County has a water quality grade of C (54.0/100). 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 Onondaga County have so many water violations?

Onondaga County has 68 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 Onondaga County rank for water quality in New York?

Onondaga County ranks #13 out of 57 counties in New York by SDWIS water quality score (1 = best). With a score of 54.0/100, it falls in the top 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

Warren County

New York

52.0

Water score

Chautauqua County

New York

56.4

Water score

Cortland County

New York

51.4

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 May 14, 2026Reviewed by Evan Brooks, Data Editor

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