Utilities, COLUMBIA CITY OF

NPDES permit SC0020940 · Major POTW · administratively continued, expires 2023-05-31 · EPA's file as of 2026-09-19

Check this month's numbers before you file

This permit expired on 2023-05-31 and is administratively continued: 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

5values over a limit
0required values missing, on 0 form(s)
0of 16 forms filed late

Last period with anything received: 2026-07-31. Most often over: Chlorine, total residual (4), E. coli (1).

Reporting

Reports are due about 29 days after each monitoring period ends (the most common figure among SC permits in EPA's filings — check your permit).

Limits in force (57)

OutfallParameterStatisticLimitMonths
001Oxygen demand, ultimateMO AVG <= 38163 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Oxygen demand, ultimateMO AVG <= 57914 lb/d Jan, Feb, Nov, Dec
001Oxygen demand, ultimateWKLY AVG <= 57244 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Oxygen demand, ultimateWKLY AVG <= 86871 lb/d Jan, Feb, Nov, Dec
001Oxygen, dissolved [DO]MINIMUM >= 5 mg/L all year
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMO AVG <= 30 mg/L Jan, Feb, Nov, Dec
001BOD, 5-day, 20 deg. CWKLY AVG <= 45 mg/L Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CWKLY AVG <= 45 mg/L Jan, Feb, Nov, Dec
001BOD, 5-day, 20 deg. CMO AVG <= 15012 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMO AVG <= 15012 lb/d Jan, Feb, Nov, Dec
001BOD, 5-day, 20 deg. CWKLY AVG <= 22518 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CWKLY AVG <= 22518 lb/d Jan, Feb, Nov, Dec
001pHMINIMUM >= 6 SU all year
001pHMAXIMUM <= 8.5 SU all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedWKLY AVG <= 45 mg/L all year
001Solids, total suspendedMO AVG <= 15012 lb/d all year
001Solids, total suspendedWKLY AVG <= 22518 lb/d all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]WKLY AVG report only all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]WKLY AVG report only all year
001Nitrogen, ammonia total [as N]MO AVG <= 13.93 mg/L Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MO AVG <= 20 mg/L Jan, Feb, Nov, Dec
001Nitrogen, ammonia total [as N]WKLY AVG <= 20.89 mg/L Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]WKLY AVG <= 30 mg/L Jan, Feb, Nov, Dec
001Nitrogen, ammonia total [as N]MO AVG <= 6971 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]MO AVG <= 10008 lb/d Jan, Feb, Nov, Dec
001Nitrogen, ammonia total [as N]WKLY AVG <= 10453 lb/d Mar, Apr, May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]WKLY AVG <= 15012 lb/d Jan, Feb, Nov, Dec
001Phosphorus, total [as P]MO AVG report only all year
001Phosphorus, total [as P]WKLY AVG report only all year
001Phosphorus, total [as P]MO AVG report only all year
001Phosphorus, total [as P]WKLY AVG report only all year
001Copper, total [as Cu]MO AVG report only all year
001Copper, total [as Cu]DAILY MX report only all year
001Copper, total [as Cu]MO AVG report only all year
001Copper, total [as Cu]DAILY MX report only all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantWKLY AVG report only all year
001Chlorine, total residualMO AVG <= .1 mg/L all year
001Chlorine, total residualDAILY MX <= .17 mg/L all year
001Chlorine, total residualMO AVG <= 50.04 lb/d all year
001Chlorine, total residualDAILY MX <= 85.07 lb/d all year
001E. coli30DAVGEO <= 126 MPN/100mL all year
001E. coliDAILY MX <= 349 MPN/100mL all year
001E. coli30DAVGEO <= 126 MPN/100mL all year
001E. coliDAILY MX <= 800 MPN/100mL all year
001Mercury, total [as Hg]MO AVG report only all year
001Mercury, total [as Hg]DAILY MX report only all year
001Mercury, total [as Hg]MO AVG report only all year
001Mercury, total [as Hg]DAILY MX report only all year
001BOD, 5-day, percent removalMO AV MN >= 85 % all year
001Solids, suspended percent removalMO AV MN >= 85 % all year
001%Effect Static Renewal 7 Day Chronic Ceriodaphnia dubiaMO AVG <= 25 % all year
001%Effect Static Renewal 7 Day Chronic Ceriodaphnia dubiaDAILY MX <= 40 % 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