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County water report

St. Joseph County Water Report

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

Water grade

B

Water score

68.6

State rank

#19

of 92

Health violations

3

EPA SDWIS, 5-year lookback

Watershed impaired

53.8%

184 water bodies assessed

Monitoring sites

93

11,363 recent measurements

Live streamflow

121%

ST. JOSEPH RIVER AT SOUTH BEND, IN

Water at a glance

Key Water Indicators for St. Joseph County

EPA SDWIS

Safety Grade

B

Score: 68.6 / 100

EPA SDWIS

Active Violations

3

5-year health-based lookback

EPA ATTAINS

Watershed Health

54% impaired

184 bodies assessed

USGS NWIS

Streamflow Snapshot

121% of mean

ST. JOSEPH RIVER AT SOUTH BEND, IN

EPA WQP

Monitoring Sites

93

11,363 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.

68.6/100

Health violations

3

Health-based violations

Violations per 100K served

1.6

Population-normalized SDWIS rate

Data center water stress

St. Joseph County has 3 facilities in the DCWSI dataset.

ByCounty's DCWSI ranks this county #94 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.

65.6

0-100 index

Facility count

3

61.1 density percentile

Discharge estimate

Not reported

EPA CWA fields where available

Water vs median

+18.6

Compared with US county median

Named operators

AWS

Mapped facilities

  • Amazon AWS Data Center

    Amazon

    OSM

  • Amazon AWS Data Center

    Amazon

    OSM

  • AMAZON DATA SERVICES INCORPORATED

    NEW CARLISLE · Amazon Data Services

    EPA ECHO
See the St. Joseph County data-center reportReview methodology

Data Center Water Budget Calculator

Estimate daily water use for a hypothetical facility in St. Joseph County.

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

Your facility would use 10.7% of this county's industrial water baseline — manageable but worth monitoring against drought trends.

10.7% of county industrial baseline6.67 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 St. Joseph County’s Water

Drinking Water Quality Overview

EPA SDWIS

St. Joseph County earns a B grade for drinking water quality, scoring 68.6 out of 100. Over the past five years, EPA SDWIS records 3 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 53.8% of assessed waterways are impaired (99 of 184 water bodies) across St. Joseph County's watersheds. The leading impairment causes are escherichia coli (e. coli) and biological integrity. 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 2026-05-14T14:15:00.000-04:00) puts ST. JOSEPH RIVER at 4.4k 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. St. Joseph County has extensive coverage with 93 active monitoring sites with 11,363 recent measurements on record. Predominant monitoring categories include physical and organics, pesticide. 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 St. Joseph County

Water Verdict

St. Joseph County, Indiana receives a fair water quality assessment with a grade of B and a score of 68.6 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 184 water bodies in the county's watershed, with 53.8% 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 120.5%.

Violation Context

EPA SDWIS records for St. Joseph County, Indiana show 3 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 1.6 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: 11,363 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 St. Joseph County scores well above average for drinking-water safety. St. Joseph County's drinking-water compliance score is 68.6 out of 100. With 3 recorded health violations, the water supply is generally reliable. The violation rate for St. Joseph County is 1.6 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 St. Joseph County's watershed. With 93 active water-quality monitoring sites in St. Joseph County, data coverage is strong. Live streamflow monitoring from the ST. JOSEPH RIVER gauge is also available on this page.

Regional Context

St. Joseph County has better water quality than the average county in Indiana. Its water score is 16.1 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 St. Joseph County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    E. coli (bacteria)

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

  • 2

    Biological Integrity

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

  • 3

    Pcbs in Fish Tissue

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for St. Joseph County

EPA How's My Waterway

Interactive watershed health data for St. Joseph County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for St. Joseph County

Consumer Confidence Reports (IN)

Annual water quality reports from utilities in Indiana

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

53.8%

99 of 184 assessed

Moderate concern

Top Impairment Causes

  • 1

    ESCHERICHIA COLI (E. COLI)

  • 2

    BIOLOGICAL INTEGRITY

  • 3

    PCBS IN FISH TISSUE

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

93

Active in the past 5 years

Measurements Recorded

11K

11,363 total readings

Most Measured

  • Physical
  • Organics, Pesticide
  • 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).

Live USGS Streamgage

River & Stream Conditions

Current Discharge

4,400cfs

May 14, 6:15 PM UTC

vs Long-Term Average

121%

Above typical

Primary Streamgage

ST. JOSEPH RIVER AT SOUTH BEND, IN

USGS site
04101225
Drainage area
3,619 sq mi
Long-term mean
3,652 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 St. Joseph 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.

Try the full calculator →

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Frequently Asked Questions

What is the water quality in St. Joseph County, Indiana?
St. Joseph County, Indiana has a drinking-water quality grade of B with a score of 68.6/100, 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 streamflow snapshots are reported separately on this page.
Are there any water violations in St. Joseph County?
St. Joseph 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 St. Joseph County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 53.8% of St. Joseph County's 184 assessed water bodies are classified as impaired (99 impaired). The top reported causes are ESCHERICHIA COLI (E. COLI), BIOLOGICAL INTEGRITY, PCBS IN FISH TISSUE. 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 St. Joseph County?
EPA's Water Quality Portal records 11,363 measurements from 93 monitoring sites in St. Joseph County over the past five years. The most frequently measured characteristic groups are Physical, Organics, Pesticide, 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.
What's happening with rivers in St. Joseph County right now?
St. Joseph County's primary USGS streamgage on the ST. JOSEPH RIVER has a pipeline snapshot of 4,400 cubic feet per second — 121% of the long-term mean of 3,651.6 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does St. Joseph County water compare to the Indiana average?
St. Joseph County's SDWIS water quality score of 68.6/100 is higher 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 St. Joseph County?
Based on EPA SDWIS data, St. Joseph County has a water quality grade of B (68.6/100). 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 St. Joseph County have clean drinking water?
St. Joseph County has 3 health-based drinking water violations according to EPA records. With a water quality score of 68.6/100 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 St. Joseph County rank for water quality in Indiana?
St. Joseph County ranks #19 out of 92 counties in Indiana by SDWIS water quality score (1 = best). With a score of 68.6/100, it falls in the top 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

Lake County

Indiana

B

68.4

Water score

Harrison County

Indiana

B

67.1

Water score

Jackson County

Indiana

B

66.8

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.

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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