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Federal water data

County water report

Cass County Water Report

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

Water grade

B

Water score

69.7

State rank

#39

of 52

Health violations

2

EPA SDWIS, 5-year lookback

Watershed impaired

41.7%

60 water bodies assessed

Monitoring sites

29

37,474 recent measurements

Live streamflow

121%

SHEYENNE RIVER AT WEST FARGO, ND

Water at a glance

Key Water Indicators for Cass County

EPA SDWIS

Safety Grade

B

Score: 69.7 / 100

EPA SDWIS

Active Violations

2

5-year health-based lookback

EPA ATTAINS

Watershed Health

42% impaired

60 bodies assessed

USGS NWIS

Streamflow Snapshot

121% of mean

SHEYENNE RIVER AT WEST FARGO, ND

EPA WQP

Monitoring Sites

29

37,474 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.

69.7/100

Health violations

2

Health-based violations

Violations per 100K served

1.1

Population-normalized SDWIS rate

Data center water stress

Cass County has 2 facilities in the DCWSI dataset.

ByCounty's DCWSI ranks this county #127 nationally by combining its water score with mapped data center density.

DCWSIThe Data Center Water Stress Index: 60% the county's water-system stress plus 40% how concentrated data centers already are, scored 0-100. Higher means data-center density and water pressure overlap more here.

59.8

0-100 index

Facility count

2

45.0 density percentile

Discharge estimate

Not reported

EPA CWA fields where available

Water vs median

+19.7

Compared with US county median

Mapped facilities

  • Applied Digital

    Harwood

    OSM

  • Dakota Carrier Network

    Facility details limited

    OSM
See the Cass County data-center reportReview methodology

Data Center Water Budget Calculator

Estimate daily water use for a hypothetical facility in Cass County.

1 MW1,000 MW
40%100%
799K gallons/dayHigh Impact

Your facility would use 89.6% of this county's industrial water baseline. Verify water rights and long-term drought projections before committing.

89.6% of county industrial baseline0.09 Mgal/day remaining headroom

Based on USGS 2020 water-use data and EPA-standard cooling intensity constants. Not a substitute for site-specific water rights analysis.

Editorial analysis

Understanding Cass County’s Water

Drinking Water Quality Overview

EPA SDWIS

Cass County earns a B grade for drinking water quality, scoring 69.7 out of 100. Over the past five years, EPA SDWIS records 2 health-based violations — a small cluster that warrants attention.

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 substantial 41.7% of assessed waterways are impaired (25 of 60 water bodies) across Cass County's watersheds. The leading impairment causes are escherichia coli (e. coli) and physical substrate habitat alterations. 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 403.0 cfs — flowing above its historical average at 121% 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. Cass County has moderate coverage with 29 active monitoring sites with 37,474 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 Cass County

Water Verdict

Cass County, North Dakota receives a fair water quality assessment with a grade of B and a score of 69.7 out of 100. The water supply meets baseline federal standards, but there may be periods of elevated contaminant levels or infrastructure concerns worth monitoring. Separately, EPA ATTAINS assessments cover 60 water bodies in the county's watershed, with 41.7% 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 running above its historical mean at 120.6%.

Violation Context

EPA SDWIS records for Cass County, North Dakota show 2 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 1.1 violations per 100,000 people served, this rate is relatively low compared to many U.S. counties. This compliance record sits alongside an unusually deep monitoring archive: 37,474 water-quality results have been logged across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

Tap water in Cass County scores well above average for drinking-water safety. Cass County's drinking-water compliance score is 69.7 out of 100. With 2 recorded health violations, the water supply is generally reliable. The violation rate for Cass County is 1.1 per 100,000 people served. Households with infants, pregnant individuals, or immunocompromised members may want to use an NSF 53-certified pitcher filter as a low-cost precaution. E. coli is the leading impairment cause in Cass County's watershed. With 29 active water-quality monitoring sites in Cass County, data coverage is strong. A pipeline streamflow snapshot from the SHEYENNE RIVER gauge is also available on this page.

Regional Context

Cass County has water quality close to the average county in North Dakota. Its water score is within 1.9 points of the state average, meaning its overall water system performance is broadly representative of North Dakota as a whole.

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 Cass County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    E. coli (bacteria)

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

  • 2

    Physical Substrate Habitat Alterations

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

  • 3

    Combined Biota/Habitat Bioassessments

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Cass County

EPA How's My Waterway

Interactive watershed health data for Cass County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Cass County

Consumer Confidence Reports (ND)

Annual water quality reports from utilities in North Dakota

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

41.7%

25 of 60 assessed

Moderate concern

Top Impairment Causes

  • 1

    ESCHERICHIA COLI (E. COLI)

  • 2

    PHYSICAL SUBSTRATE HABITAT ALTERATIONS

  • 3

    COMBINED BIOTA/HABITAT BIOASSESSMENTS

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

29

Active in the past 5 years

Measurements Recorded

37K

37,474 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

403cfs

May 14, 7:00 PM UTC

vs Long-Term Average

121%

Above typical

Primary Streamgage

SHEYENNE RIVER AT WEST FARGO, ND

USGS site
05059500
Drainage area
8,870 sq mi
Long-term mean
334 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 Cass County:C — Moderate

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 Cass County, North Dakota?
Cass County, North Dakota has a drinking-water quality grade of B with a score of 69.7/100, based on EPA SDWIS compliance data. The county has 2 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 Cass County?
Cass County has 2 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 Cass County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 41.7% of Cass County's 60 assessed water bodies are classified as impaired (25 impaired). The top reported causes are ESCHERICHIA COLI (E. COLI), PHYSICAL SUBSTRATE HABITAT ALTERATIONS, COMBINED BIOTA/HABITAT BIOASSESSMENTS. 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 Cass County?
EPA's Water Quality Portal records 37,474 measurements from 29 monitoring sites in Cass 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 Cass County right now?
Cass County's primary USGS streamgage on the SHEYENNE RIVER has a pipeline snapshot of 403 cubic feet per second — 121% of the long-term mean of 334.2 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does Cass County water compare to the North Dakota average?
Cass County's SDWIS water quality score of 69.7/100 is lower 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 Cass County?
Based on EPA SDWIS data, Cass County has a water quality grade of B (69.7/100). 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 Cass County have clean drinking water?
Cass County has 2 health-based drinking water violations according to EPA records. With a water quality score of 69.7/100 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 Cass County rank for water quality in North Dakota?
Cass County ranks #39 out of 52 counties in North Dakota by SDWIS water quality score (1 = best). With a score of 69.7/100, 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

Williams County

North Dakota

C

61.7

Water score

McKenzie County

North Dakota

C

57.5

Water score

Stutsman County

North Dakota

C

56.4

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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