Irwin City Of STP
Irwin, IA · Shelby County · Publicly Owned Treatment Works
- Average flow
- —
- Design flow
- 0.1 MGD
- NPDES permit
- IA0021024
- Effective
- Permit expires
- May 2027
- Population served
- 319
- CWNS 2022
Irwin City Of STP is a publicly owned wastewater treatment works in Irwin, Shelby County, Iowa, serving about 319 residents. Treatment on site includes uncovered lagoons. It discharges under NPDES permit IA0021024 (effective), which expires in May 2027, with 0 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Uncovered lagoons
Unlock
Unlock exact unit counts →
Compliance snapshot (last 3 years)
- Total violations
- 0
- Effluent violations
- 0
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
1 verified contact for Irwin City Of STP, with validated emails and direct phone numbers.
Unlock 1 verified contact
Names, validated emails and direct phone numbers for decision-makers at Irwin City Of STP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Iowa
Defiance · 6 mi away
—
Manilla · 7 mi away
—
Earling · 11 mi away
—
Harlan · 11 mi away
—
Manning · 12 mi away
—
Kimballton · 13 mi away
—
Elk Horn · 16 mi away
—
Templeton · 17 mi away
—
Irwin City Of STP: 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 September 11, 2026; facility record last updated March 28, 2025.