What is the address of Onslow City Of STP?

The address on the plant’s EPA facility record is Elm St, Onslow, IA 52321, in Jones County. Its coordinates are 42.1045, -91.0066. For some plants the record holds the utility’s mailing address rather than the plant gate.

What treatment technology does Onslow City Of STP use?

Klarifi has identified one treatment structure or unit process at the Onslow facility. The full treatment train, with exact unit counts, is shown in Klarifi with a free account.

What is the NPDES permit for Onslow City Of STP?

The facility discharges under NPDES permit IA0057134, currently effective, expiring October 2029.

Is Onslow City Of STP in compliance?

Discharge monitoring reports show 1 violation at Onslow City Of STP in the last three years, 1 of them effluent limit exceedances. The full history is available in Klarifi.

Who operates Onslow City Of STP and how do I contact them?

Onslow City Of STP is a publicly owned treatment works in Onslow, Iowa. Klarifi lists 1 verified decision-maker contact for this facility, available with a free trial.

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Onslow City Of STP

Elm St, Onslow, IA 52321 · Jones County · Publicly Owned Treatment Works

Average flow: —

Design flow: —

NPDES permit: IA0057134; Effective

Permit expires: October 2029

Population served: 201; CWNS 2022

Onslow City Of STP is a publicly owned wastewater treatment works in Onslow, Jones County, Iowa, serving about 201 residents. It discharges under NPDES permit IA0057134 (effective), which expires in October 2029, with 1 recorded violation in the last three years.

Treatment technology

One treatment structure or unit process identified at Onslow City Of STP.

Available with a free Klarifi account

See the full treatment train at Onslow City Of STP: structures, unit processes and planned upgrades, with exact unit counts.

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Compliance snapshot (last 3 years)

Total violations: 1

Effluent violations: 1

Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.

Key contacts

1 verified contact for Onslow 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 Onslow City Of STP, plus the full compliance history and discharge data.

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Wyoming WWTP

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Monticello WWTP

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Onslow 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 March 16, 2025.

Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Ozonation · Activated sludge · all terms

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