Clean Water Act discharge permit · NPDES IA0058581

THOR CITY OF STP, Thor, IA: NPDES IA0058581 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MinorDischarger class
9Pollutants under a numeric limit
1Pollutants with an effluent exceedance
0Inspections on file
0Formal enforcement actions

THOR CITY OF STP, held by CITY OF THOR, holds NPDES permit IA0058581. EPA’s file records it issued August 1, 2016 and expiring July 31, 2021.

THOR CITY OF STP, Thor, Iowa: Individual permit IA0058581, held by CITY OF THOR; Publicly owned treatment works; Administratively continued (past its expiration date and still in force until reissued); issued August 1, 2016, term to July 31, 2021, by STA; Sewage Treatment Facilities.

pH: 2 limits, 49 violations of any kind, 1 effluent exceedance, latest October 31, 2018.
Solids, total suspended: 7 limits, 49 violations of any kind, 0 effluent exceedances.
BOD, carbonaceous [5 day, 20 C]: 7 limits, 47 violations of any kind, 0 effluent exceedances.
Annual Nitrate Nitrogen Discharged: 1 limit, 28 violations of any kind, 0 effluent exceedances.
Nitrogen, ammonia total [as N]: 5 limits, 0 violations of any kind, 0 effluent exceedances.
Chloride [as Cl]: 5 limits, 0 violations of any kind, 0 effluent exceedances.
Sulfate, total [as SO4]: 5 limits, 0 violations of any kind, 0 effluent exceedances.
E. coli: 3 limits, 0 violations of any kind, 0 effluent exceedances.
Depth of pond or reservoir in feet: 3 limits, 0 violations of any kind, 0 effluent exceedances.

Iowa holds 734 Publicly owned treatment works coverages of this permit type in EPA’s file; 139 were issued before IA0058581.

Coverages issued nearest IA0058581

August 1, 2016: LUANA CITY OF STP, Luana, IA0027685, held by CITY OF LUANA
August 1, 2016: ROCK RAPIDS CITY OF STP, Rock Rapids, IA0032786, held by ROCK RAPIDS MUNICIPAL UTILITIES
August 1, 2016: DALLAS CENTER CITY OF STP, Dallas Center, IA0035319, held by CITY OF DALLAS CENTER
August 1, 2016: GRANGER CITY OF STP, Granger, IA0041912, held by CITY OF GRANGER
August 1, 2016: CLEGHORN CITY OF STP, Cleghorn, IA0042846, held by CITY OF CLEGHORN
August 1, 2016: KELLERTON CITY OF STP, Kellerton, IA0061760, held by CITY OF KELLERTON
August 1, 2016: MENLO CITY OF STP, Menlo, IA0071374, held by CITY OF MENLO
August 1, 2016: MAPLE RIVER JUNCTION STP, Carroll, IA0081639, held by CARROLL COUNTY
September 1, 2016: WHITING CITY OF STP, Whiting, IA0032719, held by CITY OF WHITING
September 1, 2016: TEMPLETON CITY OF STP, Templeton, IA0033782, held by CITY OF TEMPLETON

THOR CITY OF STP among its neighbors

EPA’s permit file holds 1 discharge permits in the Drainage Ditch 3 subwatershed (HUC 071000050603), IA0058581 among them. Its county holds 6, 1 of them major permits; IA0058581 is a minor permit.

Identity

Facility as filed	THOR CITY OF STP
Permittee as filed	CITY OF THOR
NPDES ID	IA0058581
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Individual permit
Discharger class	Minor discharger
Facility type	Publicly owned treatment works
Program	Publicly owned treatment works
Issued	August 1, 2016
Expiration date	July 31, 2021
Issuing agency	STA
Address	Thor, IA 50591
Subwatershed	Drainage Ditch 3 (HUC 071000050603)
NAICS	221320 – Sewage Treatment Facilities
SIC	4952 – Sewerage Systems

Effluent limits and exceedances

9Pollutants on file
9Under a numeric limit
4With a violation of any kind
1With an effluent exceedance

An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.

Pollutant or measure	Limits	Violations, any kind	Effluent exceedances	Latest exceedance
pH	2	49	1	October 31, 2018
Solids, total suspended	7	49	0
BOD, carbonaceous [5 day, 20 C]	7	47	0
Annual Nitrate Nitrogen Discharged	1	28	0
Nitrogen, ammonia total [as N]	5	0	0
Chloride [as Cl]	5	0	0
Sulfate, total [as SO4]	5	0	0
E. coli	3	0	0
Depth of pond or reservoir in feet	3	0	0

Inspections, violations and enforcement

0Single-event violations

EPA’s single-event violation file, as loaded, holds no violation for NPDES IA0058581.

Inspections

EPA’s inspection file holds no inspection for NPDES IA0058581.

Formal enforcement and penalties

0 formal actions, 0 of them with a penalty assessed. Federal and state penalties are separate figures from separate authorities and are shown as each was filed, never added together.

Informal enforcement

EPA’s informal enforcement file holds no action for NPDES IA0058581.

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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.

This public-records page covers Clean Water Act discharge permit NPDES IA0058581 for THOR CITY OF STP in Thor, IA, held by CITY OF THOR, a minor discharger classed as a publicly owned treatment works. The permit is administratively continued, with an issue date of August 1, 2016 and an expiration date of July 31, 2021. The page lists 9 pollutants on file, 1 of which is under a numeric limit and 1 of which has an effluent exceedance.