waterbycounty
EPA SDWIS

Custer County Water Quality

Custer County, Nebraska

Water Grade

F

Water Score

35.4

Violations

3

State Rank

#62

of 90 (1 = best)

EPA SDWIS Compliance

Drinking Water Quality

Water Quality Grade

F

Based on EPA compliance history and violation data

Water Score

35.4/100

Higher = better quality

Health Violations

3

Health-based violations

Violation Rate

45.4%

Systems with violations

Water Advisory: Custer County

Water Verdict

Custer County receives a poor water quality assessment with a grade of F and a score of 35.4 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.

Violation Context

Custer County has recorded 3 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 45.4 violations per 1,000 residents, this rate is high and signals significant water quality management issues.

Consumer Guidance

Residents of Custer 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 3 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

Custer County has poorer water quality than the average county in Nebraska. Its water score is 22.7 points lower than the state average, suggesting more challenges with contamination control or infrastructure than neighboring counties.

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

64.3%

9 of 14 assessed

High concern

Top Impairment Causes

  • 1

    MERCURY IN FISH TISSUE

  • 2

    ESCHERICHIA COLI (E. COLI)

  • 3

    CAUSE UNKNOWN

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

17

Active in the past 5 years

Measurements Recorded

1.3K

1,341 total readings

Most Measured

  • Inorganics, Minor, Metals
  • Physical
  • Inorganics, Major, Non-metals

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

869cfs

May 14, 6:15 PM UTC

vs Long-Term Average

82%

Below typical

Primary Streamgage

Middle Loup River near Gates, Nebr.

USGS site
06777495
Drainage area
3,800 sq mi
Long-term mean
1,065 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.

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 Custer County, Nebraska?
Custer County, Nebraska has a drinking-water quality grade of F with a score of 35.4/100, based on EPA SDWIS compliance data. The county has 3 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 Custer County?
Custer County has 3 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 Custer County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 64.3% of Custer County's 14 assessed water bodies are classified as impaired (9 impaired). The top reported causes are MERCURY IN FISH TISSUE, ESCHERICHIA COLI (E. COLI), CAUSE UNKNOWN. 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 Custer County?
EPA's Water Quality Portal records 1,341 measurements from 17 monitoring sites in Custer County over the past five years. The most frequently measured characteristic groups are Inorganics, Minor, Metals, Physical, Inorganics, Major, Non-metals. 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 Custer County right now?
Custer County's primary USGS streamgage on the Middle Loup River is currently reading 869 cubic feet per second — 82% of the long-term mean of 1,065.45 cfs. Flow is within typical range for this gauge. For genuine real-time data, visit waterdata.usgs.gov.
How does Custer County water compare to the Nebraska average?
Custer County's SDWIS water quality score of 35.4/100 is lower than the Nebraska state average of 58.1. The average water quality grade across Nebraska is D, based on data from 90 counties with available SDWIS data.
Is tap water safe to drink in Custer County?
Based on EPA SDWIS data, Custer County has a water quality grade of F (35.4/100). 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).
Does Custer County have clean drinking water?
Custer County has 3 health-based drinking water violations according to EPA records. With a water quality score of 35.4/100 and grade F, 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 Custer County rank for water quality in Nebraska?
Custer County ranks #62 out of 90 counties in Nebraska by SDWIS water quality score (1 = best). With a score of 35.4/100, 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

Butler County

Nebraska

F

36.0

Water score

Cass County

Nebraska

F

36.6

Water score

Thayer County

Nebraska

F

32.3

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.

Watershed health and impaired-waterway data from the EPA ATTAINS Clean Water Act §303(d) assessments — state-reported, 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 Logan Johnson, Founder & Data EditorUpdated Reviewed by Logan Johnson, Founder & Data Editor

Explore more data for Custer County

Property TaxCost of LivingCrime RateIncomeHealthSchoolsDisaster RiskWeatherCounty Score