Onarga Stp, Village Of
658 E 1600 North Township Rd, Onarga, IL 60955 · Iroquois County · Publicly Owned Treatment Works
- Average flow
- 0.05 MGD
- Design flow
- 0.88 MGD
- NPDES permit
- IL0076813
- Effective
- Permit expires
- September 2028
- Population served
- 1,409
- CWNS 2022
Onarga Stp, Village Of is a publicly owned wastewater treatment works in Onarga, Iroquois County, Illinois treating an average of 0.05 million gallons per day against a permitted design capacity of 0.88 MGD, serving about 1,409 residents. It discharges under NPDES permit IL0076813 (effective), which expires in September 2028, with 13 recorded violations in the last three years. EPA has recorded 2 formal enforcement actions naming the plant, the latest in April 2023.
Treatment technology
1 planned upgrade on record at Onarga Stp, Village Of.
Available with a free Klarifi account
See the full treatment train at Onarga Stp, Village Of: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 13
- Effluent violations
- 13
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
EPA enforcement history
Federal civil enforcement cases, compliance inspections and informal actions recorded for Onarga Stp, Village Of in EPA's ICIS system.
- Formal actions
- 2
- 1 since FY2020
- Compliance actions
- $1.8M
- required by EPA orders
- EPA inspections
- 0
- none on record
Latest case · Apr 2023
Village of Onarga STP
Administrative order · CWA, NPDES Permit Violations · Superseded by Another Enforcement Action · Compliance actions $80,000
Source: EPA ECHO, civil enforcement case 05-2014-0309.
Full case history with a free Klarifi account
Every action against Onarga Stp, Village Of with dates, milestones, violation types and EPA's complete case summaries, plus inspections and informal actions.
Key contacts
Decision-makers at Onarga Stp, Village Of.
No verified contacts on file yet
Klarifi verifies plant and municipal decision-makers continuously. Start a free trial to browse contacts at nearby plants and flag this one for verification.
Nearby wastewater treatment plants in Illinois
Gilman · 3 mi away
0.46 MGD
Cissna Park · 14 mi away
0.04 MGD
Watseka · 14 mi away
1.09 MGD
Chatsworth · 15 mi away
0.1 MGD
Clifton · 15 mi away
0.09 MGD
Milford · 19 mi away
0.5 MGD
Forrest · 22 mi away
0.24 MGD
Paxton · 22 mi away
0.68 MGD
Onarga Stp, Village Of: frequently asked questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed October 26, 2026; facility record last updated May 18, 2025.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Centrate · Ozonation · all terms