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County water report

Woodford County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Woodford County, Illinois.

Water grade

F

Water score

21.0

State rank

#89

of 102

Health violations

31

EPA SDWIS, 5-year lookback

Watershed impaired

50.1%

423 water bodies assessed

Monitoring sites

2

716 recent measurements

Live streamflow

52%

MACKINAW RIVER NEAR CONGERVILLE, IL

Water at a glance

Key Water Indicators for Woodford County

EPA SDWIS

Safety Grade

F

Score: 21.0 / 100

EPA SDWIS

Active Violations

31

5-year health-based lookback

EPA ATTAINS

Watershed Health

50% impaired

423 bodies assessed

USGS NWIS

Streamflow Snapshot

52% of mean

MACKINAW RIVER NEAR CONGERVILLE, IL

EPA WQP

Monitoring Sites

2

716 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.

21.0/100

Health violations

31

Health-based violations

Violations per 100K served

121.5

Population-normalized SDWIS rate

Editorial analysis

Understanding Woodford County’s Water

Drinking Water Quality Overview

EPA SDWIS

Woodford County's water systems carry a failing grade, scoring 21.0 out of 100. Over the past five years, EPA SDWIS records 31 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 50.1% of assessed waterways are impaired (212 of 423 water bodies) across Woodford County's watersheds. The leading impairment causes are phosphorus, total and total suspended solids (tss). 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 2026-05-14T12:45:00.000-06:00) puts MACKINAW RIVER at 291.0 cfs — well below its long-term average at 52% 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. Woodford County has limited coverage with 2 active monitoring sites with 716 recent measurements on record. Predominant monitoring categories include nutrient and physical. 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 Woodford County

Water Verdict

Woodford County, Illinois receives a poor water quality assessment with a grade of F and a score of 21.0 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. Separately, EPA ATTAINS assessments cover 423 water bodies in the county's watershed, with 50.1% 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 52.1% — worth watching in drier seasons.

Violation Context

EPA SDWIS records for Woodford County, Illinois show 31 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 121.5 violations per 100,000 people served, this rate is high and signals significant water quality management issues. Independent monitoring is comparatively sparse here — 716 water-quality results logged in the EPA Water Quality Portal over the past five years — so the utility's own reporting carries extra weight.

Consumer Guidance

Woodford County has a Grade F compliance record with 31 health-based violations — among the highest levels in the country. Woodford County's drinking-water compliance score is 21.0 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 Illinois Department of Environmental Quality or Health can expedite utility compliance action. Phosphorus, Total is the leading impairment cause in Woodford County's watershed. There are 2 active water-quality monitoring sites in Woodford County. A pipeline streamflow snapshot from the MACKINAW RIVER gauge is also available on this page.

Regional Context

Woodford County has poorer water quality than the average county in Illinois. Its water score is 26.8 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 Woodford County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    Phosphorus (excess nutrients)

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

  • 2

    Total Suspended Solids (Tss)

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

  • 3

    Mercury

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Woodford County

EPA How's My Waterway

Interactive watershed health data for Woodford County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Woodford County

Consumer Confidence Reports (IL)

Annual water quality reports from utilities in Illinois

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

50.1%

212 of 423 assessed

Moderate concern

Top Impairment Causes

  • 1

    PHOSPHORUS, TOTAL

  • 2

    TOTAL SUSPENDED SOLIDS (TSS)

  • 3

    MERCURY

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

2

Active in the past 5 years

Measurements Recorded

716

716 total readings

Most Measured

  • Nutrient
  • Physical
  • Inorganics, Major, Non-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

291cfs

May 14, 6:45 PM UTC

vs Long-Term Average

52%

Well below typical

Primary Streamgage

MACKINAW RIVER NEAR CONGERVILLE, IL

USGS site
05567500
Drainage area
767 sq mi
Long-term mean
558 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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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 Woodford 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 Woodford County, Illinois?
Woodford County, Illinois has a drinking-water quality grade of F with a score of 21.0/100, based on EPA SDWIS compliance data. The county has 31 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 Woodford County?
Woodford County has 31 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 Woodford County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 50.1% of Woodford County's 423 assessed water bodies are classified as impaired (212 impaired). The top reported causes are PHOSPHORUS, TOTAL, TOTAL SUSPENDED SOLIDS (TSS), MERCURY. 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 Woodford County?
EPA's Water Quality Portal records 716 measurements from 2 monitoring sites in Woodford County over the past five years. The most frequently measured characteristic groups are Nutrient, Physical, Inorganics, Major, Non-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 Woodford County right now?
Woodford County's primary USGS streamgage on the MACKINAW RIVER has a pipeline snapshot of 291 cubic feet per second — 52% of the long-term mean of 558.3 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 Woodford County water compare to the Illinois average?
Woodford County's SDWIS water quality score of 21.0/100 is lower than the Illinois state average of 47.8. The average water quality grade across Illinois is D, based on data from 102 counties with available SDWIS data.
Is tap water safe to drink in Woodford County?
Based on EPA SDWIS data, Woodford County has a water quality grade of F (21.0/100). 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 Woodford County have so many water violations?
Woodford County has 31 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 Woodford County rank for water quality in Illinois?
Woodford County ranks #89 out of 102 counties in Illinois by SDWIS water quality score (1 = best). With a score of 21.0/100, 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

Lee County

Illinois

F

20.9

Water score

Christian County

Illinois

F

20.7

Water score

McDonough County

Illinois

F

20.3

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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