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County water report

Northumberland County Water Report

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

Water grade

B

Water score

63.2

State rank

#9

of 67

Health violations

4

EPA SDWIS, 5-year lookback

Watershed impaired

0.0%

24,000 water bodies assessed

Monitoring sites

69

27,598 recent measurements

Live streamflow

112%

West Branch Susquehanna River at Lewisburg, PA

Water at a glance

Key Water Indicators for Northumberland County

EPA SDWIS

Safety Grade

B

Score: 63.2 / 100

EPA SDWIS

Active Violations

4

5-year health-based lookback

EPA ATTAINS

Watershed Health

0% impaired

24,000 bodies assessed

USGS NWIS

Streamflow Snapshot

112% of mean

West Branch Susquehanna River at Lewisburg, PA

EPA WQP

Monitoring Sites

69

27,598 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

B

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

63.2/100

Health violations

4

Health-based violations

Violations per 100K served

4.6

Population-normalized SDWIS rate

Editorial analysis

Understanding Northumberland County’s Water

Drinking Water Quality Overview

EPA SDWIS

Northumberland County earns a B grade for drinking water quality, scoring 63.2 out of 100. Over the past five years, EPA SDWIS records 4 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 24,000 water bodies) across Northumberland 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 2026-05-14T14:45:00.000-04:00) puts West Branch Susquehanna River at 12.3k cfs — flowing above its historical average at 112% of mean. 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. Northumberland County has extensive coverage with 69 active monitoring sites with 27,598 recent measurements on record. Predominant monitoring categories include physical and inorganics, minor, metals. 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 Northumberland County

Water Verdict

Northumberland County receives a fair water quality assessment with a grade of B and a score of 63.2 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

Northumberland County has recorded 4 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 4.6 violations per 100,000 people served, this rate is moderate and suggests recurring water quality challenges.

Consumer Guidance

Tap water in Northumberland County meets baseline safety standards, though the compliance record shows some violations worth watching. Northumberland County's drinking-water compliance score is 63.2 out of 100. The violation rate for Northumberland County is 4.6 per 100,000 people served. Running tap water for 30 seconds before drinking can reduce any localized lead exposure from household plumbing. Requesting your utility's most recent Consumer Confidence Report is the fastest way to identify which specific contaminants were flagged. With 69 active water-quality monitoring sites in Northumberland County, data coverage is strong. A pipeline streamflow snapshot from the West Branch Susquehanna River gauge is also available on this page.

Regional Context

Northumberland County has better water quality than the average county in Pennsylvania. Its water score is 24.3 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.

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

0.0%

0 of 24,000 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

69

Active in the past 5 years

Measurements Recorded

28K

27,598 total readings

Most Measured

  • Physical
  • Inorganics, Minor, Metals
  • 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

12.3Kcfs

May 14, 6:45 PM UTC

vs Long-Term Average

112%

Above typical

Primary Streamgage

West Branch Susquehanna River at Lewisburg, PA

USGS site
01553500
Drainage area
6,847 sq mi
Long-term mean
11.0K 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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Annual Total

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Monthly

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Water Bill

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Filter Cost

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Safety Grade for Northumberland County:CModerate

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 Northumberland County, Pennsylvania?
Northumberland County, Pennsylvania has a drinking-water quality grade of B with a score of 63.2/100, based on EPA SDWIS compliance data. The county has 4 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 Northumberland County?
Northumberland County has 4 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 Northumberland County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 0.0% of Northumberland County's 24,000 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 Northumberland County?
EPA's Water Quality Portal records 27,598 measurements from 69 monitoring sites in Northumberland County over the past five years. The most frequently measured characteristic groups are Physical, Inorganics, Minor, Metals, 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 Northumberland County right now?
Northumberland County's primary USGS streamgage on the West Branch Susquehanna River has a pipeline snapshot of 12,300 cubic feet per second — 112% of the long-term mean of 11,010.76 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does Northumberland County water compare to the Pennsylvania average?
Northumberland County's SDWIS water quality score of 63.2/100 is higher 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 Northumberland County?
Based on EPA SDWIS data, Northumberland County has a water quality grade of B (63.2/100). This indicates good to excellent water quality with strong SDWIS compliance. 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).
Does Northumberland County have clean drinking water?
Northumberland County has 4 health-based drinking water violations according to EPA records. With a water quality score of 63.2/100 and grade B, the county's drinking water has had some compliance issues but continues to be monitored. Note: drinking-water compliance speaks to the public water system, not necessarily to the watershed itself — check the Watershed Health zone for ATTAINS §303(d) data.
How does Northumberland County rank for water quality in Pennsylvania?
Northumberland County ranks #9 out of 67 counties in Pennsylvania by SDWIS water quality score (1 = best). With a score of 63.2/100, 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.

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