CITY OF NORTHWOOD — NPDES permit IA0032395: limits, due date and EPA's record

NPDES permit IA0032395 · Minor POTW · effective, expires 2029-09-30 · EPA's file as of 2026-09-19

EPA's record, 2025-09-01 to 2026-08-31

Reporting

Reports are due about 15 days after each monitoring period ends (the most common figure among IA permits in EPA's filings — check your permit).

Limits in force (134)

Outfall	Parameter	Statistic	Limit	Months
001	Oxygen, dissolved [DO]	DAILY MN	>= 1 mg/L	all year
001	BOD, 5-day, 20 deg. C	30DA AVG	report only	all year
001	BOD, 5-day, 20 deg. C	DAILY MX	report only	all year
001	BOD, 5-day, 20 deg. C	30DA AVG	report only	all year
001	BOD, 5-day, 20 deg. C	DAILY MX	report only	all year
001	pH	DAILY MN	>= 6 SU	all year
001	pH	DAILY MX	<= 9 SU	all year
001	pH	30DA AVG	report only	all year
001	pH	DAILY MX	report only	all year
001	Solids, total suspended	30DA AVG	<= 30 mg/L	all year
001	Solids, total suspended	7 DA AVG	<= 45 mg/L	all year
001	Solids, total suspended	30DA AVG	<= 207 lb/d	all year
001	Solids, total suspended	7 DA AVG	<= 311 lb/d	all year
001	Solids, total suspended	30DA AVG	report only	all year
001	Solids, total suspended	DAILY MX	report only	all year
001	Solids, total suspended	30DA AVG	report only	all year
001	Solids, total suspended	DAILY MX	report only	all year
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 21.7 mg/L	Oct
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 49.7 mg/L	Feb
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 12 mg/L	Aug
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 16.8 mg/L	May
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 31.4 mg/L	Nov
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 13.2 mg/L	Jul
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 12.5 mg/L	Sep
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 45.1 mg/L	Jan
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 35.9 mg/L	Dec
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 20 mg/L	Apr
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 10.8 mg/L	Jun
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 26.4 mg/L	Mar
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 58.1 mg/L	Oct
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 85.6 mg/L	Feb
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 53 mg/L	Aug
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 65.4 mg/L	May
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 56.6 mg/L	Nov
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 48 mg/L	Jul
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 59.3 mg/L	Sep
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 75.5 mg/L	Jan
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 58.4 mg/L	Dec
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 58 mg/L	Apr
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 63 mg/L	Jun
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 73.9 mg/L	Mar
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 83.6 lb/d	Oct
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 179.7 lb/d	Feb
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 41.7 lb/d	Aug
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 59.8 lb/d	May
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 117.6 lb/d	Nov
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 45.7 lb/d	Jul
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 45 lb/d	Sep
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 167.8 lb/d	Jan
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 142.9 lb/d	Dec
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 71 lb/d	Apr
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 39.2 lb/d	Jun
001	Nitrogen, ammonia total [as N]	30DA AVG	<= 98.5 lb/d	Mar
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 249.1 lb/d	Oct
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 325.3 lb/d	Feb
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 150.7 lb/d	Aug
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 268.6 lb/d	May
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 239.3 lb/d	Nov
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 132.7 lb/d	Jul
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 215.7 lb/d	Sep
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 299 lb/d	Jan
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 251.4 lb/d	Dec
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 248.8 lb/d	Apr
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 181.1 lb/d	Jun
001	Nitrogen, ammonia total [as N]	DAILY MX	<= 291.8 lb/d	Mar
001	Nitrogen, Kjeldahl, total [as N]	30DA AVG	report only	all year
001	Nitrogen, Kjeldahl, total [as N]	DAILY MX	report only	all year
001	Nitrogen, Kjeldahl, total [as N]	30DA AVG	report only	all year
001	Nitrogen, Kjeldahl, total [as N]	DAILY MX	report only	all year
001	E. coli	GEO MEAN	<= 126 #/100mL	Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
001	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 25 mg/L	all year
001	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 40 mg/L	all year
001	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 173 lb/d	all year
001	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 277 lb/d	all year
002	Oxygen, dissolved [DO]	DAILY MN	>= 1 mg/L	all year
002	pH	DAILY MN	>= 6.3 SU	all year
002	pH	DAILY MX	<= 9 SU	all year
002	Solids, total suspended	30DA AVG	<= 30 mg/L	all year
002	Solids, total suspended	7 DA AVG	<= 45 mg/L	all year
002	Solids, total suspended	30DA AVG	<= 207 lb/d	all year
002	Solids, total suspended	7 DA AVG	<= 311 lb/d	all year
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 3.6 mg/L	Aug
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 12.9 mg/L	Jan
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 14.8 mg/L	Feb
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 5.6 mg/L	May
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 8.8 mg/L	Nov
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 5.9 mg/L	Oct
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 9.3 mg/L	Dec
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 5.7 mg/L	Apr
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 3.7 mg/L	Jun
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 4 mg/L	Sep
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 7.6 mg/L	Mar
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 3.8 mg/L	Jul
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 17.8 mg/L	Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16.9 mg/L	Jan
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16.1 mg/L	Feb
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16.7 mg/L	May
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16 mg/L	Nov
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 17.1 mg/L	Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 17.4 mg/L	Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 17.1 mg/L	Apr
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15.9 mg/L	Jun
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 18 mg/L	Sep
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 16.3 mg/L	Mar
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 19.3 mg/L	Jul
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 15.5 lb/d	Aug
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 77 lb/d	Jan
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 87.1 lb/d	Feb
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 24.5 lb/d	May
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 49.2 lb/d	Nov
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 37.9 lb/d	Oct
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 57.8 lb/d	Dec
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 28.6 lb/d	Apr
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 16.8 lb/d	Jun
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 18.9 lb/d	Sep
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 39.7 lb/d	Mar
002	Nitrogen, ammonia total [as N]	30DA AVG	<= 17 lb/d	Jul
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 117.3 lb/d	Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 112.9 lb/d	Jan
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 107.5 lb/d	Feb
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 110.1 lb/d	May
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 106.6 lb/d	Nov
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 114.5 lb/d	Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 116.4 lb/d	Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 113.8 lb/d	Apr
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 104.8 lb/d	Jun
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 120.1 lb/d	Sep
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 108.3 lb/d	Mar
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 127.6 lb/d	Jul
002	E. coli	GEO MEAN	<= 126 #/100mL	Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov
002	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 25 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 40 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	30DA AVG	<= 173 lb/d	all year
002	BOD, carbonaceous [5 day, 20 C]	7 DA AVG	<= 277 lb/d	all year