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County water report

Warren County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Warren County, Pennsylvania.

Water grade

F

Water score

9.4

State rank

#64

of 67

Health violations

86

EPA SDWIS, 5-year lookback

Watershed impaired

0.0%

14,647 water bodies assessed

Monitoring sites

40

21,689 recent measurements

Live streamflow

184%

Allegheny River bl Conewango Creek at Warren, PA

Water at a glance

Key Water Indicators for Warren County

EPA SDWIS

Safety Grade

F

Score: 9.4 / 100

EPA SDWIS

Active Violations

86

5-year health-based lookback

EPA ATTAINS

Watershed Health

0% impaired

14,647 bodies assessed

USGS NWIS

Streamflow Snapshot

184% of mean

Allegheny River bl Conewango Creek at Warren, PA

EPA WQP

Monitoring Sites

40

21,689 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

F

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

9.4/100

Health violations

86

Health-based violations

Violations per 100K served

362.9

Population-normalized SDWIS rate

Editorial analysis

Understanding Warren County’s Water

Drinking Water Quality Overview

EPA SDWIS

Warren County's water systems carry a failing grade, scoring 9.4 out of 100. Over the past five years, EPA SDWIS records 86 health-based violations — a pattern that public water utilities are required to disclose and correct.

Watershed Conditions

EPA ATTAINS

Under the Clean Water Act §303(d), EPA ATTAINS tracks whether waterways meet quality standards for drinking, recreation, and aquatic life (reporting cycle: 2022). None of the assessed waterways are listed as impaired (0 of 14,647 water bodies) across Warren County's watersheds. Impairment does not mean tap water is unsafe — it measures ambient waterway conditions upstream of treatment, not finished drinking water.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T15:00:00.000-04:00) puts Allegheny River bl Conewango Creek at 11.2k cfs — running significantly above its long-term average at 184% 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. Warren County has moderate coverage with 40 active monitoring sites with 21,689 recent measurements on record. Predominant monitoring categories include inorganics, minor, metals and physical. 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 Warren County

Water Verdict

Warren County, Pennsylvania receives a poor water quality assessment with a grade of F and a score of 9.4 out of 100. The water supply has documented quality issues. Residents are strongly encouraged to use filtered or bottled water for drinking and to stay informed about utility improvement plans. Separately, EPA ATTAINS assessments track 14,647 water bodies in the county's watershed, none of which are currently listed as impaired under the Clean Water Act. At the most recent USGS reading, local streamflow was running above its historical mean at 184.3%.

Violation Context

EPA SDWIS records for Warren County, Pennsylvania show 86 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 362.9 violations per 100,000 people served, this rate is high and signals significant water quality management issues. This compliance record sits alongside an unusually deep monitoring archive: 21,689 water-quality results have been logged across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

Warren County has a Grade F compliance record with 86 health-based violations — among the highest levels in the country. Warren County's drinking-water compliance score is 9.4 out of 100. Residents are strongly advised to use a certified NSF 58 reverse-osmosis filter or bottled water for all drinking and cooking until violations are corrected. Contacting the Pennsylvania Department of Environmental Quality or Health can expedite utility compliance action. With 40 active water-quality monitoring sites in Warren County, data coverage is strong. A pipeline streamflow snapshot from the Allegheny River bl Conewango Creek gauge is also available on this page.

Regional Context

Warren County has poorer water quality than the average county in Pennsylvania. Its water score is 29.5 points lower than the state average, suggesting more challenges with contamination control or infrastructure than 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 Warren County's water environment

Official EPA Resources for Warren County

EPA How's My Waterway

Interactive watershed health data for Warren County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Warren County

Consumer Confidence Reports (PA)

Annual water quality reports from utilities in Pennsylvania

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

0.0%

0 of 14,647 assessed

Mostly healthy

Top Impairment Causes

No specific impairment causes reported for the assessed water bodies in this county.

Source: EPA ATTAINS · Reporting cycle 2022

Impairment is determined under the Clean Water Act §303(d): a water body is impaired when it fails to meet state-defined quality standards for designated uses (drinking, recreation, aquatic life). Assessment coverage varies by state; counties without assessed water bodies are not shown.

Past 5 years

Water Quality Monitoring

Monitoring Sites

40

Active in the past 5 years

Measurements Recorded

22K

21,689 total readings

Most Measured

  • Inorganics, Minor, Metals
  • Physical
  • Nutrient

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

11.2Kcfs

May 14, 7:00 PM UTC

vs Long-Term Average

184%

Well above typical

Primary Streamgage

Allegheny River bl Conewango Creek at Warren, PA

USGS site
03015310
Drainage area
3,131 sq mi
Long-term mean
6,077 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.

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Water Cost Estimate

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Annual Total

$558

Monthly

$47

Water Bill

$558/yr

Filter Cost

$0/yr

Safety Grade for Warren 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.

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Frequently Asked Questions

What is the water quality in Warren County, Pennsylvania?
Warren County, Pennsylvania has a drinking-water quality grade of F with a score of 9.4/100, based on EPA SDWIS compliance data. The county has 86 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 Warren County?
Warren County has 86 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 healthy are the watersheds in Warren County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 0.0% of Warren County's 14,647 assessed water bodies are classified as impaired (0 impaired). Impairment means the water body fails to meet state quality standards for at least one designated use — drinking water source, recreation, aquatic life, or fish consumption. Note: watershed impairment doesn't always translate to tap-water issues; treatment plants can remove most regulated contaminants.
How much water-quality monitoring happens in Warren County?
EPA's Water Quality Portal records 21,689 measurements from 40 monitoring sites in Warren County over the past five years. The most frequently measured characteristic groups are Inorganics, Minor, Metals, Physical, Nutrient. 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 Warren County right now?
Warren County's primary USGS streamgage on the Allegheny River bl Conewango Creek has a pipeline snapshot of 11,200 cubic feet per second — 184% of the long-term mean of 6,076.94 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 Warren County water compare to the Pennsylvania average?
Warren County's SDWIS water quality score of 9.4/100 is lower than the Pennsylvania state average of 38.9. The average water quality grade across Pennsylvania is F, based on data from 67 counties with available SDWIS data.
Is tap water safe to drink in Warren County?
Based on EPA SDWIS data, Warren County has a water quality grade of F (9.4/100). This indicates below-average compliance with significant violations. Residents may want to consider home water filtration or independent testing. 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 Warren County have so many water violations?
Warren County has 86 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 Warren County rank for water quality in Pennsylvania?
Warren County ranks #64 out of 67 counties in Pennsylvania by SDWIS water quality score (1 = best). With a score of 9.4/100, it falls in the bottom 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

Bedford County

Pennsylvania

F

9.2

Water score

Wyoming County

Pennsylvania

F

9.0

Water score

McKean County

Pennsylvania

F

9.9

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.

Watershed health and impaired-waterway data from the EPA ATTAINS Clean Water Act §303(d) assessments, state-reported and EPA-finalized.

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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