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Federal water data

County water report

Madison County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Madison County, Montana.

Water grade

F

Water score

28.6

State rank

#35

of 55

Health violations

7

EPA SDWIS, 5-year lookback

Watershed impaired

0.0%

78 water bodies assessed

Monitoring sites

59

5,206 recent measurements

Live streamflow

No gauge

Jefferson River at Parsons Bdg nr Silver Star, MT

Water at a glance

Key Water Indicators for Madison County

EPA SDWIS

Safety Grade

F

Score: 28.6 / 100

EPA SDWIS

Active Violations

7

5-year health-based lookback

EPA ATTAINS

Watershed Health

0% impaired

78 bodies assessed

USGS NWIS

Streamflow Snapshot

No gauge

Jefferson River at Parsons Bdg nr Silver Star, MT

EPA WQP

Monitoring Sites

59

5,206 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.

28.6/100

Health violations

7

Health-based violations

Violations per 100K served

73.1

Population-normalized SDWIS rate

Editorial analysis

Understanding Madison County’s Water

Drinking Water Quality Overview

EPA SDWIS

Madison County's water systems carry a failing grade, scoring 28.6 out of 100. Over the past five years, EPA SDWIS records 7 health-based violations — a pattern that public water utilities are required to disclose and correct.

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). None of the assessed waterways are listed as impaired (0 of 78 water bodies) across Madison County's watersheds. Impairment does not mean tap water is unsafe — it measures ambient waterway conditions upstream of treatment, not finished drinking water.

Monitoring Network

EPA WQP

EPA's Water Quality Portal (WQP) aggregates monitoring data from federal, state, and tribal agencies. Madison County has extensive coverage with 59 active monitoring sites with 5,206 recent measurements on record. Predominant monitoring categories include physical and nutrient. 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 Madison County

Water Verdict

Madison County receives a poor water quality assessment with a grade of F and a score of 28.6 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

Madison County has recorded 7 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 73.1 violations per 100,000 people served, this rate is high and signals significant water quality management issues.

Consumer Guidance

Drinking-water compliance in Madison County is rated Grade F, reflecting significant health-based violations in the recent reporting period. Madison County's drinking-water compliance score is 28.6 out of 100. The violation rate for Madison County is 73.1 per 100,000 people served. An NSF 53 or NSF 58-certified filter is recommended for drinking and cooking water. Check the Consumer Confidence Report from your utility to identify the specific contaminants and required corrective actions — utilities are legally required to notify customers of violations. With 59 active water-quality monitoring sites in Madison County, data coverage is strong. A pipeline streamflow snapshot from the Jefferson River gauge is also available on this page.

Regional Context

Madison County has poorer water quality than the average county in Montana. Its water score is 20.3 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 Madison County's water environment

Official EPA Resources for Madison County

EPA How's My Waterway

Interactive watershed health data for Madison County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Madison County

Consumer Confidence Reports (MT)

Annual water quality reports from utilities in Montana

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

0.0%

0 of 78 assessed

Mostly healthy

Top Impairment Causes

No specific impairment causes reported for the assessed water bodies in this county.

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

59

Active in the past 5 years

Measurements Recorded

5.2K

5,206 total readings

Most Measured

  • Physical
  • Nutrient
  • Biological, Counts

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).

Free tool

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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 Madison 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 Madison County, Montana?
Madison County, Montana has a drinking-water quality grade of F with a score of 28.6/100, based on EPA SDWIS compliance data. The county has 7 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 Madison County?
Madison County has 7 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 Madison County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 0.0% of Madison County's 78 assessed water bodies are classified as impaired (0 impaired). 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 Madison County?
EPA's Water Quality Portal records 5,206 measurements from 59 monitoring sites in Madison County over the past five years. The most frequently measured characteristic groups are Physical, Nutrient, Biological, Counts. 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.
How does Madison County water compare to the Montana average?
Madison County's SDWIS water quality score of 28.6/100 is lower than the Montana state average of 48.9. The average water quality grade across Montana is D, based on data from 55 counties with available SDWIS data.
Is tap water safe to drink in Madison County?
Based on EPA SDWIS data, Madison County has a water quality grade of F (28.6/100). 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 Madison County have so many water violations?
Madison County has 7 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 Madison County rank for water quality in Montana?
Madison County ranks #35 out of 55 counties in Montana by SDWIS water quality score (1 = best). With a score of 28.6/100, 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

Toole County

Montana

F

27.2

Water score

Lake County

Montana

F

30.7

Water score

Hill County

Montana

F

26.5

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.

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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