RIO
EPA ID: IL0950450 · 265 people served · 1 ZIP code
Although compliance varies widely among water utilities nationally, RIO stands out with zero EPA violations over five consecutive monitoring years, delivering safe tap water to 265 residents and showing no enforcement activity across the entire reporting span.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for RIO Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The RIO serves a community with a median household income of $80,192 and an estimated 430 residents across its service area. Approximately 74% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 56% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
RIO's water is pumped from underground aquifers. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
About 1% of homes in Knox County, Illinois rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 70th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in Illinois
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
RIO (EPA ID: IL0950450) is a community water system in Illinois that serves approximately 265 people from groundwater sources.
This system serves ZIP code 61472 in Rio.
Average Home Safety Score: C (66/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 61472 | 0.0016 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
- 61472 — Rio
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for RIO (IL0950450) on EPA.gov.
Frequently Asked Questions
Is RIO water safe to drink?
Based on EPA records, RIO has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does RIO serve?
RIO serves approximately 265 people across 1 ZIP code in Illinois.
Where does RIO get its water?
The primary water source is groundwater.
Treatment regime
How this utility classifies its treatment process and what each reported treatment chemical does.
Treatment chemicals and what each one does
Chemical names are reported verbatim by the utility. Purpose categories are ZipCheckup annotations based on standard drinking-water treatment practice.
Treatment classification and chemical list sourced from RIO Consumer Confidence Report.
Treatment intensity is a ZipCheckup-derived classification based on the chemicals and processes the utility reports. Chemicals and contamination sources are taken verbatim from the utility's CCR filing. Routine federal monitoring and contaminant testing shown elsewhere on this page determine whether the water meets safety standards, not the treatment classification.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
RIO (EPA ID: IL0950450) — request the latest Consumer Confidence Report or ask about specific contaminants.