COLCHESTER, CITY OF — NPDES permit IL0028177: limits, due date and EPA's record

NPDES permit IL0028177 · Minor POTW · effective, expires 2031-01-31 · EPA's file as of 2026-09-19

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

Last period with anything received: 2026-08-31. Most often over: BOD, carbonaceous [5 day, 20 C] (1), Solids, total suspended (1), Nitrogen, ammonia total [as N] (1).

Reporting

Reports are due about 25 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (43)

Outfall	Parameter	Statistic	Limit	Months
002	Oxygen, dissolved [DO]	MO AV MN	>= 5.5 mg/L	Jan, Feb, Aug, Sep, Oct, Nov, Dec
002	Oxygen, dissolved [DO]	MN WK AV	>= 4 mg/L	Jan, Feb, Aug, Sep, Oct, Nov, Dec
002	Oxygen, dissolved [DO]	MN WK AV	>= 6 mg/L	Mar, Apr, May, Jun, Jul
002	Oxygen, dissolved [DO]	DAILY MN	>= 3.5 mg/L	Jan, Feb, Aug, Sep, Oct, Nov, Dec
002	Oxygen, dissolved [DO]	DAILY MN	>= 5 mg/L	Mar, Apr, May, Jun, Jul
002	pH	MINIMUM	>= 6 SU	all year
002	pH	MAXIMUM	<= 9 SU	all year
002	Solids, total suspended	MO AVG	<= 12 mg/L	all year
002	Solids, total suspended	DAILY MX	<= 24 mg/L	all year
002	Solids, total suspended	MO AVG	<= 47 lb/d	all year
002	Solids, total suspended	DAILY MX	<= 94 lb/d	all year
002	Nitrogen, ammonia total [as N]	MO AVG	<= 2.5 mg/L	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	MO AVG	<= 1.5 mg/L	Jun, Jul, Aug
002	Nitrogen, ammonia total [as N]	MO AVG	<= 7.1 mg/L	Jan, Feb, Nov, Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 14 mg/L	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 12 mg/L	Jun, Jul, Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 15 mg/L	Jan, Feb, Nov, Dec
002	Nitrogen, ammonia total [as N]	MO AVG	<= 9.8 lb/d	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	MO AVG	<= 5.9 lb/d	Jun, Jul, Aug
002	Nitrogen, ammonia total [as N]	MO AVG	<= 28 lb/d	Jan, Feb, Nov, Dec
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 56 lb/d	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 47 lb/d	Jun, Jul, Aug
002	Nitrogen, ammonia total [as N]	DAILY MX	<= 59 lb/d	Jan, Feb, Nov, Dec
002	Nitrogen, ammonia total [as N]	WKLY AVG	<= 6.3 mg/L	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	WKLY AVG	<= 3.5 mg/L	Jun, Jul, Aug
002	Nitrogen, ammonia total [as N]	WKLY AVG	<= 25 lb/d	Mar, Apr, May, Sep, Oct
002	Nitrogen, ammonia total [as N]	WKLY AVG	<= 14 lb/d	Jun, Jul, Aug
002	Flow, in conduit or thru treatment plant	MO AVG	report only	all year
002	Flow, in conduit or thru treatment plant	DAILY MX	report only	all year
002	Chlorine, total residual	DAILY MX	<= .05 mg/L	all year
002	Coliform, fecal general	DAILY MX	report only	May, Jun, Jul, Aug, Sep, Oct
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	<= 10 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	DAILY MX	<= 20 mg/L	all year
002	BOD, carbonaceous [5 day, 20 C]	MO AVG	<= 39 lb/d	all year
002	BOD, carbonaceous [5 day, 20 C]	DAILY MX	<= 78 lb/d	all year
004	BOD, 5-day, 20 deg. C	DAILY MX	report only	all year
004	Solids, total suspended	DAILY MX	report only	all year
004	Coliform, fecal general	DAILY MX	report only	all year
004	Flow	MO TOTAL	report only	all year
INF	BOD, 5-day, 20 deg. C	MO AVG	report only	all year
INF	Solids, total suspended	MO AVG	report only	all year
INF	Flow, in conduit or thru treatment plant	MO AVG	report only	all year
INF	Flow, in conduit or thru treatment plant	DAILY MX	report only	all year