Marshalltown City Of STP
1001 Woodland St, Marshalltown, IA 50158 · Marshall County · Publicly Owned Treatment Works
- Average flow
- —
- Design flow
- 17.44 MGD
- NPDES permit
- IA0038610
- Effective
- Permit expires
- October 2027
- Population served
- 27,591
- CWNS 2022
Marshalltown City Of STP is a publicly owned wastewater treatment works in Marshalltown, Marshall County, Iowa, serving about 27,591 residents. It discharges under NPDES permit IA0038610 (effective), which expires in October 2027, with 7 recorded violations in the last three years.
Treatment technology
3 treatment structures and unit processes identified at Marshalltown City Of STP.
Available with a free Klarifi account
See the full treatment train at Marshalltown City Of STP: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 7
- Effluent violations
- 7
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Industrial users and pretreatment
Industries that discharge process wastewater to Marshalltown City Of STP, from the plant's pretreatment programme records.
- Industrial users
- 1
- on record
On record: Marshall County Sanitary Landfill (Marshalltown). Most users are in landfills and waste management.
Unlock the details behind these industrial users
Discharge flow, federal category, source documents and contacts for every industrial user of Marshalltown City Of STP. Free with a Klarifi account.
Key contacts
4 verified contacts for Marshalltown City Of STP, with validated emails and direct phone numbers.
Unlock 4 verified contacts (1 more than shown)
Names, validated emails and direct phone numbers for decision-makers at Marshalltown City Of STP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Iowa
Albion · 5 mi away
0.07 MGD
Le Grand · 8 mi away
0.08 MGD
Liscomb · 10 mi away
—
Conrad · 11 mi away
0.07 MGD
Beaman · 11 mi away
—
Montour · 11 mi away
0.03 MGD
Garwin · 11 mi away
—
Garwin · 11 mi away
—
Marshalltown 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 October 26, 2026; facility record last updated August 18, 2026.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Anaerobic digester · Lift station · all terms