Water Quality: Monmouth, IL

4 water systems • 12,734 people served

Multiple Health Violations
32
Total Violations
11
Health-Based Violations
4
Water Systems
12,734
Population Served

Water Quality Summary

Monmouth is served by 4 public water systems with a combined service population of 12,734 people, and has 32 EPA Safe Drinking Water Act violations on record. Critically, 11 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Monmouth's violation count is 11% above the national average for Illinois. Contaminants associated with violations include Barium, Disinfection Byproducts, TTHM, Total Organic Carbon.

Contaminants Found

Barium

Increases blood pressure and causes cardiovascular effects with long-term exposure.

Common source: Natural rock deposits, oil drilling operations, coal power plant waste

EPA limit: 2 mg/L

Disinfection Byproducts

Broad category of chemicals formed during disinfection, associated with increased cancer risk and adverse reproductive effects.

Common source: Reaction of disinfectants (chlorine, ozone, chloramines) with organic matter

TTHM

Total trihalomethanes are linked to increased risk of bladder cancer and adverse reproductive outcomes.

Common source: Reaction of chlorine disinfectants with naturally occurring organic matter in water

EPA limit: 0.080 mg/L (80 ppb)

Total Organic Carbon

Not a direct health risk but reacts with disinfectants to form carcinogenic byproducts such as trihalomethanes.

Common source: Decaying plant material, algae, soil organic matter in source water

EPA limit: Treatment technique (must reduce TOC based on source water level)

Water Systems Serving Monmouth

System Name PWSID Source Population Violations
MONMOUTH IL1870150 Groundwater 8,902 3
ABINGDON IL0950050 Groundwater 3,275 18
LITTLE SWAN LAKE SD IL1875050 Groundwater 438 4
ST AUGUSTINE IL0950500 Groundwater 119 7

Concerned About Your Water?

A home water filter can remove common contaminants. NSF-certified filters are tested against EPA standards.

Consider a reverse osmosis system for comprehensive filtration or a carbon filter for basic improvement.

Other Cities in Illinois

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Data Sources

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). Data includes all recorded violations for active community water systems.

Verify at epa.govSearch ECHO for IL