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County water report

De Witt County Water Report

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

Water grade

C

Water score

56.9

State rank

#38

of 102

Health violations

1

EPA SDWIS, 5-year lookback

Watershed impaired

40.0%

145 water bodies assessed

Monitoring sites

N/A

EPA Water Quality Portal

Live streamflow

37%

SALT CREEK NEAR ROWELL, IL

Water at a glance

Key Water Indicators for De Witt County

EPA SDWIS

Safety Grade

C

Score: 56.9 / 100

EPA SDWIS

Active Violations

1

5-year health-based lookback

EPA ATTAINS

Watershed Health

40% impaired

145 bodies assessed

USGS NWIS

Streamflow Snapshot

37% of mean

SALT CREEK NEAR ROWELL, IL

EPA WQP

Monitoring Sites

N/A

Rolling 5-year window

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

C

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

56.9/100

Health violations

1

Health-based violations

Violations per 100K served

8.9

Population-normalized SDWIS rate

Editorial analysis

Understanding De Witt County’s Water

Drinking Water Quality Overview

EPA SDWIS

De Witt County's drinking water earned a C grade, scoring 56.9 out of 100. Over the past five years, EPA SDWIS records 1 health-based violation — a single incident worth monitoring.

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 40.0% of assessed waterways are impaired (58 of 145 water bodies) across De Witt County's watersheds. The leading impairment causes are dissolved oxygen and fecal coliform. 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 2026-05-14T12:30:00.000-06:00) puts SALT CREEK at 101.0 cfs — well below its long-term average at 37% 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.

Editorial advisory

What the data suggests for De Witt County

Water Verdict

De Witt County, Illinois receives a fair water quality assessment with a grade of C and a score of 56.9 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 145 water bodies in the county's watershed, with 40.0% 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 36.9% — worth watching in drier seasons.

Violation Context

EPA SDWIS records for De Witt County, Illinois show 1 health-based violation, meaning a water system experienced at least one exceedance of federal contaminant limits or treatment requirements. At 8.9 violations per 100,000 people served, this rate is high and signals significant water quality management issues. The most recent Clean Water Act assessment cycle on file for the county's watershed is 2022.

Consumer Guidance

Tap water in De Witt County meets baseline standards but the compliance record shows room for improvement, with a Grade C rating. De Witt County's drinking-water compliance score is 56.9 out of 100. The violation rate for De Witt County is 8.9 per 100,000 people served. Residents who are immunocompromised, pregnant, or have young children may benefit from using an NSF 53-certified filter. Contacting your local utility for the current Consumer Confidence Report will confirm which specific violations were recorded and whether they have been resolved. Dissolved Oxygen is the leading impairment cause in De Witt County's watershed. A pipeline streamflow snapshot from the SALT CREEK gauge is also available on this page.

Regional Context

De Witt County has better water quality than the average county in Illinois. Its water score is 9.1 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 De Witt County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    Low dissolved oxygen

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

  • 2

    Fecal coliform bacteria

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

  • 3

    Phosphorus (excess nutrients)

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for De Witt County

EPA How's My Waterway

Interactive watershed health data for De Witt County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for De Witt County

Consumer Confidence Reports (IL)

Annual water quality reports from utilities in Illinois

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

40.0%

58 of 145 assessed

Moderate concern

Top Impairment Causes

  • 1

    DISSOLVED OXYGEN

  • 2

    FECAL COLIFORM

  • 3

    PHOSPHORUS, TOTAL

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.

Live USGS Streamgage

River & Stream Conditions

Current Discharge

101cfs

May 14, 6:30 PM UTC

vs Long-Term Average

37%

Well below typical

Primary Streamgage

SALT CREEK NEAR ROWELL, IL

USGS site
05578500
Drainage area
335 sq mi
Long-term mean
273 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 De Witt 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 De Witt County, Illinois?
De Witt County, Illinois has a drinking-water quality grade of C with a score of 56.9/100, based on EPA SDWIS compliance data. The county has 1 health-based drinking water violation over the past 5 years. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in De Witt County?
De Witt County has 1 health-based drinking water violation 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 De Witt County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 40.0% of De Witt County's 145 assessed water bodies are classified as impaired (58 impaired). The top reported causes are DISSOLVED OXYGEN, FECAL COLIFORM, PHOSPHORUS, TOTAL. 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.
What's happening with rivers in De Witt County right now?
De Witt County's primary USGS streamgage on the SALT CREEK has a pipeline snapshot of 101 cubic feet per second — 37% of the long-term mean of 273.36 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 De Witt County water compare to the Illinois average?
De Witt County's SDWIS water quality score of 56.9/100 is higher 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 De Witt County?
Based on EPA SDWIS data, De Witt County has a water quality grade of C (56.9/100). This indicates moderate compliance. Some violations have been recorded but overall standards are maintained. 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 De Witt County have clean drinking water?
De Witt County has 1 health-based drinking water violation according to EPA records. With a water quality score of 56.9/100 and grade C, 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 De Witt County rank for water quality in Illinois?
De Witt County ranks #38 out of 102 counties in Illinois by SDWIS water quality score (1 = best). With a score of 56.9/100, 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

Cass County

Illinois

C

56.8

Water score

Winnebago County

Illinois

C

57.1

Water score

Lawrence County

Illinois

C

58.3

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.

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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