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County water report

Nelson County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Nelson County, North Dakota.

Water grade

A

Water score

86.0

State rank

#24

of 52

Health violations

0

EPA SDWIS, 5-year lookback

Watershed impaired

22.2%

36 water bodies assessed

Monitoring sites

9

12,598 recent measurements

Live streamflow

58%

SHEYENNE RIVER AT CO RD 20 NEAR KLOTEN, ND

Water at a glance

Key Water Indicators for Nelson County

EPA SDWIS

Safety Grade

A

Score: 86.0 / 100

EPA SDWIS

Active Violations

0

5-year health-based lookback

EPA ATTAINS

Watershed Health

22% impaired

36 bodies assessed

USGS NWIS

Streamflow Snapshot

58% of mean

SHEYENNE RIVER AT CO RD 20 NEAR KLOTEN, ND

EPA WQP

Monitoring Sites

9

12,598 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

A

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

86.0/100

Health violations

0

Health-based violations

Violations per 100K served

0.0

Population-normalized SDWIS rate

Editorial analysis

Understanding Nelson County’s Water

Drinking Water Quality Overview

EPA SDWIS

Nelson County earns an A grade for drinking water quality, scoring 86.0 out of 100. EPA's Safe Drinking Water Information System (SDWIS) records zero health-based violations over the past five years — a strong compliance signal for a mid-sized county.

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). A notable 22.2% of assessed waterways carry an impairment designation (8 of 36 water bodies) across Nelson County's watersheds. The leading impairment causes are escherichia coli (e. coli) and benthic macroinvertebrates bioassessments. 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 2026-05-14T14:00:00.000-05:00) puts SHEYENNE RIVER at 184.0 cfs — well below its long-term average at 58% of mean — low-flow conditions worth noting for water-dependent ecosystems. 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. Nelson County has limited coverage with 9 active monitoring sites with 12,598 recent measurements on record. Predominant monitoring categories include physical and inorganics, major, non-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 Nelson County

Water Verdict

Nelson County, North Dakota receives an excellent water quality assessment with a grade of A and a score of 86.0 out of 100. The water supply meets or exceeds federal safety standards, and residents can generally drink tap water with confidence. Separately, EPA ATTAINS assessments cover 36 water bodies in the county's watershed, with 22.2% listed as impaired under the Clean Water Act — a source-water measure that is tracked independently of tap-water compliance. At the most recent USGS reading, local streamflow was below its historical mean at 57.9% — worth watching in drier seasons.

Violation Context

EPA SDWIS records for Nelson County, North Dakota show zero health-based violations, indicating that the county's water systems met all federal safety standards during the reporting period. The violation rate is zero per 100,000 people served, which is the best possible outcome. This compliance record sits alongside an unusually deep monitoring archive: 12,598 water-quality results have been logged across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

The EPA compliance record for Nelson County shows no recent health-based violations. Nelson County's drinking-water compliance score is 86.0 out of 100. Watershed monitoring does show E. coli in local surface water — a reminder that treated drinking water and source-water quality are measured separately. Reviewing your utility's annual Consumer Confidence Report each July confirms that treatment is keeping pace with any upstream pressures. There are 9 active water-quality monitoring sites in Nelson County. A pipeline streamflow snapshot from the SHEYENNE RIVER gauge is also available on this page.

Regional Context

Nelson County has better water quality than the average county in North Dakota. Its water score is 14.4 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.

Contaminants & Resources

Key issues flagged in Nelson County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    E. coli (bacteria)

    Impairment cause per EPA Clean Water Act §303(d) assessment

  • 2

    Benthic Macroinvertebrates Bioassessments

    Impairment cause per EPA Clean Water Act §303(d) assessment

  • 3

    Sedimentation and siltation

    Impairment cause per EPA Clean Water Act §303(d) assessment

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Nelson County

EPA How's My Waterway

Interactive watershed health data for Nelson County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Nelson County

Consumer Confidence Reports (ND)

Annual water quality reports from utilities in North Dakota

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

22.2%

8 of 36 assessed

Some impairment

Top Impairment Causes

  • 1

    ESCHERICHIA COLI (E. COLI)

  • 2

    BENTHIC MACROINVERTEBRATES BIOASSESSMENTS

  • 3

    SEDIMENTATION/SILTATION

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

9

Active in the past 5 years

Measurements Recorded

13K

12,598 total readings

Most Measured

  • Physical
  • Inorganics, Major, Non-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

184cfs

May 14, 7:00 PM UTC

vs Long-Term Average

58%

Well below typical

Primary Streamgage

SHEYENNE RIVER AT CO RD 20 NEAR KLOTEN, ND

USGS site
05056770
Drainage area
2,460 sq mi
Long-term mean
318 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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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 Nelson County:B — Good

Minor violations; waterways mostly healthy.

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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Nelson County has good water quality

Learn about water restrictions and conservation in your area.

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Frequently Asked Questions

What is the water quality in Nelson County, North Dakota?
Nelson County, North Dakota has a drinking-water quality grade of A with a score of 86.0/100, based on EPA SDWIS compliance data. The county has 0 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 Nelson County?
Nelson County has 0 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). Zero violations is an excellent record indicating consistent compliance with federal drinking water standards.
How healthy are the watersheds in Nelson County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 22.2% of Nelson County's 36 assessed water bodies are classified as impaired (8 impaired). The top reported causes are ESCHERICHIA COLI (E. COLI), BENTHIC MACROINVERTEBRATES BIOASSESSMENTS, SEDIMENTATION/SILTATION. 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 Nelson County?
EPA's Water Quality Portal records 12,598 measurements from 9 monitoring sites in Nelson County over the past five years. The most frequently measured characteristic groups are Physical, Inorganics, Major, Non-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 Nelson County right now?
Nelson County's primary USGS streamgage on the SHEYENNE RIVER has a pipeline snapshot of 184 cubic feet per second — 58% of the long-term mean of 317.67 cfs. This is well below typical — often a signal of drought stress on source water. For the latest gauge feed, visit waterdata.usgs.gov.
How does Nelson County water compare to the North Dakota average?
Nelson County's SDWIS water quality score of 86.0/100 is higher than the North Dakota state average of 71.6. The average water quality grade across North Dakota is C, based on data from 52 counties with available SDWIS data.
Is tap water safe to drink in Nelson County?
Based on EPA SDWIS data, Nelson County has a water quality grade of A (86.0/100). 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 Nelson County have clean drinking water?
Nelson County has 0 health-based drinking water violations according to EPA records. With a water quality score of 86.0/100 and grade A, the county's drinking water meets EPA standards with no recorded health violations. 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 Nelson County rank for water quality in North Dakota?
Nelson County ranks #24 out of 52 counties in North Dakota by SDWIS water quality score (1 = best). With a score of 86.0/100, it falls in the middle 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

Adams County

North Dakota

A

86.0

Water score

Barnes County

North Dakota

A

86.0

Water score

Billings County

North Dakota

A

86.0

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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