Plymouth City Utilities Commission

NPDES permit WI0030031 · Major POTW · expired, expires 2023-12-31 · EPA's file as of 2026-09-19

Check this month's numbers before you file
Watch this permit — $79 a month. Every Monday, from EPA's newest files: the next report due and when, whether EPA's file holds your last one, any change to this permit's limits or status, and the renewal date.

This permit expired on 2023-12-31 and is expired: its last limits keep applying until a new permit is issued, and EPA still expects the reports.

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

2values over a limit
36required values missing, on 20 form(s)
20of 24 forms filed late

Last period with anything received: 2026-06-30. Most often over: BOD, 5-day, 20 deg. C (1), Solids, total suspended (1).

Reporting

Reports are due about 15 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (61)

OutfallParameterStatisticLimitMonths
001Oxygen, dissolved [DO]DAILY MN >= 6 mg/L all year
001BOD, 5-day, 20 deg. CWKLY AVG <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CWKLY AVG <= 18 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMO AVG <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMO AVG <= 18 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CDAILY MX report only May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CDAILY MX report only Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMO AVG report only May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CWKLY AVG <= 138 lb/d May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CWKLY AVG <= 275 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001Solids, total suspendedWKLY AVG <= 18 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Solids, total suspendedWKLY AVG <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001Solids, total suspendedMO AVG <= 18 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Solids, total suspendedMO AVG <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001Solids, total suspendedDAILY MX report only Jan, Feb, Mar, Apr, Nov, Dec
001Solids, total suspendedDAILY MX report only May, Jun, Jul, Aug, Sep, Oct
001Solids, total suspendedMO AVG report only May, Jun, Jul, Aug, Sep, Oct
001Solids, total suspendedWKLY AVG <= 275 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001Solids, total suspendedWKLY AVG <= 138 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]WKLY AVG <= 9 mg/L Dec
001Nitrogen, ammonia total [as N]WKLY AVG <= 8 mg/L Oct
001Nitrogen, ammonia total [as N]WKLY AVG <= 13 mg/L Sep
001Nitrogen, ammonia total [as N]WKLY AVG <= 13 mg/L Feb
001Nitrogen, ammonia total [as N]WKLY AVG <= 20 mg/L Apr
001Nitrogen, ammonia total [as N]WKLY AVG <= 13 mg/L Jan
001Nitrogen, ammonia total [as N]WKLY AVG <= 18 mg/L Mar
001Nitrogen, ammonia total [as N]WKLY AVG <= 9.6 mg/L Nov
001Nitrogen, ammonia total [as N]WKLY AVG <= 9.4 mg/L Jul
001Nitrogen, ammonia total [as N]WKLY AVG <= 8.5 mg/L Aug
001Nitrogen, ammonia total [as N]WKLY AVG <= 28 mg/L May
001Nitrogen, ammonia total [as N]WKLY AVG <= 14 mg/L Jun
001Nitrogen, ammonia total [as N]MO AVG <= 5.1 mg/L Dec
001Nitrogen, ammonia total [as N]MO AVG <= 4.3 mg/L Oct
001Nitrogen, ammonia total [as N]MO AVG <= 7.6 mg/L Sep
001Nitrogen, ammonia total [as N]MO AVG <= 7.63 mg/L Feb
001Nitrogen, ammonia total [as N]MO AVG <= 11 mg/L Apr
001Nitrogen, ammonia total [as N]MO AVG <= 7.2 mg/L Jan
001Nitrogen, ammonia total [as N]MO AVG <= 13 mg/L Mar
001Nitrogen, ammonia total [as N]MO AVG <= 5.4 mg/L Nov
001Nitrogen, ammonia total [as N]MO AVG <= 5 mg/L Jul
001Nitrogen, ammonia total [as N]MO AVG <= 5.1 mg/L Aug
001Nitrogen, ammonia total [as N]MO AVG <= 18 mg/L May
001Nitrogen, ammonia total [as N]MO AVG <= 9 mg/L Jun
001Nitrogen, ammonia total [as N]DAILY MX report only Jun
001Phosphorus, total [as P]MO AVG <= 1 mg/L all year
001Phosphorus, total [as P]DAILY MX report only all year
001Chloride [as Cl]DAILY MX report only all year
001Chloride [as Cl]QB report only all year
001Mercury, total recoverableDAILY MX report only all year
001Mercury, total recoverableQB report only all year
001Coliform, fecal generalWK GEOMN <= 780 #/100mL May, Jun, Jul, Aug, Sep
001Coliform, fecal generalGEO MEAN <= 400 #/100mL May, Jun, Jul, Aug, Sep
701BOD, 5-day, 20 deg. CMO AVG report only all year
701BOD, 5-day, 20 deg. CDAILY MX report only all year
701Solids, total suspendedMO AVG report only all year
701Solids, total suspendedDAILY MX report only all year
701Flow, in conduit or thru treatment plantMO AVG report only all year
701Flow, in conduit or thru treatment plantDAILY MX report only all year
701Mercury, total recoverableDAILY MX report only all year

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states