waterbycounty
Federal water data

County water report

Columbia County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Columbia County, Oregon.

Water grade

F

Water score

13.9

State rank

#34

of 36

Health violations

81

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

70

159,658 recent measurements

Live streamflow

73%

COLUMBIA RIVER AT PORT WESTWARD, NEAR QUINCY, OR

Water at a glance

Key Water Indicators for Columbia County

EPA SDWIS

Safety Grade

F

Score: 13.9 / 100

EPA SDWIS

Active Violations

81

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

73% of mean

COLUMBIA RIVER AT PORT WESTWARD, NEAR QUINCY, OR

EPA WQP

Monitoring Sites

70

159,658 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.

13.9/100

Health violations

81

Health-based violations

Violations per 100K served

214.9

Population-normalized SDWIS rate

Editorial analysis

Understanding Columbia County’s Water

Drinking Water Quality Overview

EPA SDWIS

Columbia County's water systems carry a failing grade, scoring 13.9 out of 100. Over the past five years, EPA SDWIS records 81 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 2026-05-14T11:40:00.000-07:00) puts COLUMBIA RIVER at 170.0k cfs — running somewhat below its historical average at 73% 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. Columbia County has extensive coverage with 70 active monitoring sites with 159,658 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 Columbia County

Water Verdict

Columbia County, Oregon receives a poor water quality assessment with a grade of F and a score of 13.9 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. The county's primary USGS gauge drains roughly 256,900 square miles of upstream watershed, giving local source waters a regional footprint. At the most recent USGS reading, local streamflow was below its historical mean at 73.4% — worth watching in drier seasons.

Violation Context

EPA SDWIS records for Columbia County, Oregon show 81 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 214.9 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: 159,658 water-quality results have been logged across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

Columbia County has a Grade F compliance record with 81 health-based violations — among the highest levels in the country. Columbia County's drinking-water compliance score is 13.9 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 Oregon Department of Environmental Quality or Health can expedite utility compliance action. With 70 active water-quality monitoring sites in Columbia County, data coverage is strong. A pipeline streamflow snapshot from the COLUMBIA RIVER gauge is also available on this page.

Regional Context

Columbia County has poorer water quality than the average county in Oregon. Its water score is 30.7 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 Columbia County's water environment

Official EPA Resources for Columbia County

EPA How's My Waterway

Interactive watershed health data for Columbia County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Columbia County

Consumer Confidence Reports (OR)

Annual water quality reports from utilities in Oregon

Past 5 years

Water Quality Monitoring

Monitoring Sites

70

Active in the past 5 years

Measurements Recorded

160K

159,658 total readings

Most Measured

  • Physical
  • Organics, Pesticide
  • 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

170.0Kcfs

May 14, 6:40 PM UTC

vs Long-Term Average

73%

Below typical

Primary Streamgage

COLUMBIA RIVER AT PORT WESTWARD, NEAR QUINCY, OR

USGS site
14246900
Drainage area
256,900 sq mi
Long-term mean
231.7K 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 Columbia County:F — Failing

High violation count or severe watershed conditions.

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 →

Improve your water quality at home

Berkey filters remove 99.9%+ of contaminants from tap water.

Shop Berkey →

Sponsored

Test your tap water

Tap Score provides professional mail-in water testing.

Get Tested →

Frequently Asked Questions

What is the water quality in Columbia County, Oregon?
Columbia County, Oregon has a drinking-water quality grade of F with a score of 13.9/100, based on EPA SDWIS compliance data. The county has 81 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 Columbia County?
Columbia County has 81 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 Columbia County?
EPA's Water Quality Portal records 159,658 measurements from 70 monitoring sites in Columbia County over the past five years. The most frequently measured characteristic groups are Physical, Organics, Pesticide, 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 Columbia County right now?
Columbia County's primary USGS streamgage on the COLUMBIA RIVER has a pipeline snapshot of 170,000 cubic feet per second — 73% of the long-term mean of 231,652.94 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does Columbia County water compare to the Oregon average?
Columbia County's SDWIS water quality score of 13.9/100 is lower than the Oregon state average of 44.6. The average water quality grade across Oregon is D, based on data from 36 counties with available SDWIS data.
Is tap water safe to drink in Columbia County?
Based on EPA SDWIS data, Columbia County has a water quality grade of F (13.9/100). 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 Columbia County have so many water violations?
Columbia County has 81 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 Columbia County rank for water quality in Oregon?
Columbia County ranks #34 out of 36 counties in Oregon by SDWIS water quality score (1 = best). With a score of 13.9/100, 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

Curry County

Oregon

F

13.9

Water score

Coos County

Oregon

F

14.0

Water score

Wasco County

Oregon

F

15.9

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.

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

Explore more data for Columbia County

Property TaxCost of LivingCrime RateIncomeHealthSchoolsDisaster RiskWeatherCounty Score