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County water report

Decatur County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Decatur County, Indiana.

Water grade

F

Water score

11.8

State rank

#90

of 92

Health violations

55

EPA SDWIS, 5-year lookback

Watershed impaired

50.0%

134 water bodies assessed

Monitoring sites

13

1,752 recent measurements

Live streamflow

No gauge

Primary USGS station not mapped

Water at a glance

Key Water Indicators for Decatur County

EPA SDWIS

Safety Grade

F

Score: 11.8 / 100

EPA SDWIS

Active Violations

55

5-year health-based lookback

EPA ATTAINS

Watershed Health

50% impaired

134 bodies assessed

USGS NWIS

Streamflow Snapshot

No gauge

Primary USGS gauge not mapped

EPA WQP

Monitoring Sites

13

1,752 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.

11.8/100

Health violations

55

Health-based violations

Violations per 100K served

275.2

Population-normalized SDWIS rate

Editorial analysis

Understanding Decatur County’s Water

Drinking Water Quality Overview

EPA SDWIS

Decatur County's water systems carry a failing grade, scoring 11.8 out of 100. Over the past five years, EPA SDWIS records 55 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). A substantial 50.0% of assessed waterways are impaired (67 of 134 water bodies) across Decatur County's watersheds. The leading impairment causes are escherichia coli (e. coli) and pcbs in fish tissue. 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. Decatur County has moderate coverage with 13 active monitoring sites with 1,752 recent measurements on record. Predominant monitoring categories include physical and biological, counts. 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 Decatur County

Water Verdict

Decatur County receives a poor water quality assessment with a grade of F and a score of 11.8 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

Decatur County has recorded 55 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 275.2 violations per 100,000 people served, this rate is high and signals significant water quality management issues.

Consumer Guidance

Decatur County has a Grade F compliance record with 55 health-based violations — among the highest levels in the country. Decatur County's drinking-water compliance score is 11.8 out of 100. Residents are strongly advised to use a certified NSF 58 reverse-osmosis filter or bottled water for all drinking and cooking until violations are corrected. Contacting the Indiana Department of Environmental Quality or Health can expedite utility compliance action. E. coli is the leading impairment cause in Decatur County's watershed. With 13 active water-quality monitoring sites in Decatur County, data coverage is strong.

Regional Context

Decatur County has poorer water quality than the average county in Indiana. Its water score is 40.7 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 Decatur County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    E. coli (bacteria)

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

  • 2

    Pcbs in Fish Tissue

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

  • 3

    Biological Integrity

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Decatur County

EPA How's My Waterway

Interactive watershed health data for Decatur County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Decatur County

Consumer Confidence Reports (IN)

Annual water quality reports from utilities in Indiana

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

50.0%

67 of 134 assessed

Moderate concern

Top Impairment Causes

  • 1

    ESCHERICHIA COLI (E. COLI)

  • 2

    PCBS IN FISH TISSUE

  • 3

    BIOLOGICAL INTEGRITY

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

13

Active in the past 5 years

Measurements Recorded

1.8K

1,752 total readings

Most Measured

  • Physical
  • Biological, Counts
  • Inorganics, Minor, 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).

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 Decatur County:F — Failing

High violation count or severe watershed conditions.

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 Decatur County, Indiana?
Decatur County, Indiana has a drinking-water quality grade of F with a score of 11.8/100, based on EPA SDWIS compliance data. The county has 55 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 Decatur County?
Decatur County has 55 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 Decatur County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 50.0% of Decatur County's 134 assessed water bodies are classified as impaired (67 impaired). The top reported causes are ESCHERICHIA COLI (E. COLI), PCBS IN FISH TISSUE, BIOLOGICAL INTEGRITY. 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 Decatur County?
EPA's Water Quality Portal records 1,752 measurements from 13 monitoring sites in Decatur County over the past five years. The most frequently measured characteristic groups are Physical, Biological, Counts, Inorganics, Minor, 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.
How does Decatur County water compare to the Indiana average?
Decatur County's SDWIS water quality score of 11.8/100 is lower than the Indiana state average of 52.5. The average water quality grade across Indiana is D, based on data from 92 counties with available SDWIS data.
Is tap water safe to drink in Decatur County?
Based on EPA SDWIS data, Decatur County has a water quality grade of F (11.8/100). 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 Decatur County have so many water violations?
Decatur County has 55 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 Decatur County rank for water quality in Indiana?
Decatur County ranks #90 out of 92 counties in Indiana by SDWIS water quality score (1 = best). With a score of 11.8/100, 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

Posey County

Indiana

F

11.7

Water score

Warren County

Indiana

F

13.0

Water score

Fountain County

Indiana

F

13.8

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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