waterbycounty
EPA SDWIS

Benton County Water Quality

Benton County, Washington

Water Grade

F

Water Score

41.0

Violations

80

State Rank

#34

of 39 (1 = best)

EPA SDWIS Compliance

Drinking Water Quality

Water Quality Grade

F

Based on EPA compliance history and violation data

Water Score

41/100

Higher = better quality

Health Violations

80

Health-based violations

Violation Rate

30.5%

Systems with violations

Water Advisory: Benton County

Water Verdict

Benton County receives a below-average water quality assessment with a grade of F and a score of 41.0 out of 100. Residents should review their utility's Consumer Confidence Report and may want to consider additional water filtration for drinking.

Violation Context

Benton County has recorded 80 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 30.5 violations per 1,000 residents, this rate is high and signals significant water quality management issues.

Consumer Guidance

Residents of Benton County are advised to use filtered or bottled water for drinking and cooking until water quality improves. A reverse-osmosis or activated-carbon filter certified to remove the contaminants listed in the utility's Consumer Confidence Report is recommended. With 80 recorded health violations, staying informed about utility communications and boil-water notices is especially important. For long-term peace of mind, request your utility's latest Consumer Confidence Report and consider independent water testing if you have specific health concerns.

Regional Context

Benton County has poorer water quality than the average county in Washington. Its water score is 18.3 points lower than the state average, suggesting more challenges with contamination control or infrastructure than neighboring counties.

Past 5 years

Water Quality Monitoring

Monitoring Sites

11

Active in the past 5 years

Measurements Recorded

29K

29,376 total readings

Most Measured

  • Organics, Pesticide
  • 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

1,610cfs

May 14, 6:30 PM UTC

vs Long-Term Average

46%

Well below typical

Primary Streamgage

YAKIMA RIVER AT KIONA, WA

USGS site
12510500
Drainage area
5,615 sq mi
Long-term mean
3,488 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; "% of typical" compares the latest reading against that average.

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Frequently Asked Questions

What is the water quality in Benton County, Washington?
Benton County, Washington has a drinking-water quality grade of F with a score of 41.0/100, based on EPA SDWIS compliance data. The county has 80 health-based drinking water violations over the past 5 years. Watershed health, monitoring records, and live streamflow are reported separately on this page.
Are there any water violations in Benton County?
Benton County has 80 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 Benton County?
EPA's Water Quality Portal records 29,376 measurements from 11 monitoring sites in Benton County over the past five years. The most frequently measured characteristic groups are Organics, Pesticide, 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 Benton County right now?
Benton County's primary USGS streamgage on the YAKIMA RIVER is currently reading 1,610 cubic feet per second — 46% of the long-term mean of 3,487.65 cfs. This is well below typical — often a signal of drought stress on source water. For genuine real-time data, visit waterdata.usgs.gov.
How does Benton County water compare to the Washington average?
Benton County's SDWIS water quality score of 41.0/100 is lower than the Washington state average of 59.3. The average water quality grade across Washington is D, based on data from 39 counties with available SDWIS data.
Is tap water safe to drink in Benton County?
Based on EPA SDWIS data, Benton County has a water quality grade of F (41.0/100). 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 Benton County have so many water violations?
Benton County has 80 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 Benton County rank for water quality in Washington?
Benton County ranks #34 out of 39 counties in Washington by SDWIS water quality score (1 = best). With a score of 41.0/100, 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

Stevens County

Washington

F

40.7

Water score

Grant County

Washington

D

42.5

Water score

Whatcom County

Washington

D

45.3

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 Logan Johnson, Founder & Data EditorUpdated Reviewed by Logan Johnson, Founder & Data Editor

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