WASHINGTON SUBURBAN SANITARY COMMISSION - WSSC

NPDES permit MD0021491 · Major POTW · administratively continued, expires 2022-04-30 · EPA's file as of 2026-09-19

Check this month's numbers before you file

This permit expired on 2022-04-30 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

0values over a limit
0required values missing, on 0 form(s)
0of 22 forms filed late

Last period with anything received: 2026-07-31.

Reporting

Reports are due about 28 days after each monitoring period ends (read off this permit's own late-day counts in EPA's filings).

Limits in force (54)

OutfallParameterStatisticLimitMonths
001Oxygen, dissolved [DO]INST MIN >= 5 mg/L all year
001BOD, 5-day, 20 deg. CMX MO AV <= 8 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX MO AV <= 23 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX WK AV <= 12 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX WK AV <= 35 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX MO AV <= 1669 lb/d May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX MO AV <= 5007 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001BOD, 5-day, 20 deg. CMX WK AV <= 2504 lb/d May, Jun, Jul, Aug, Sep, Oct
001BOD, 5-day, 20 deg. CMX WK AV <= 7511 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001pHMINIMUM >= 6.5 SU all year
001pHMAXIMUM <= 8.5 SU all year
001Solids, total suspendedMX MO AV <= 23 mg/L all year
001Solids, total suspendedMX WK AV <= 35 mg/L all year
001Solids, total suspendedMX MO AV <= 5007 lb/d all year
001Solids, total suspendedMX WK AV <= 7511 lb/d all year
001Solids, total suspendedMO TOTAL report only all year
001Solids, total suspendedCUM TOTL <= 1824000 lb/yr all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]CUM TOTL <= 316738 lb/yr all year
001Nitrogen, total [as N]MO TOTAL report only all year
001Nitrogen, total [as N]ANNL TOT report only Dec
001Nitrogen, organic total [as N]MO AVG report only all year
001Nitrogen, ammonia total [as N]MX MO AV <= 2.5 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX MO AV <= 1.5 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]DAILY MX <= 6.7 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]DAILY MX <= 7.2 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX MO AV <= 542 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MX MO AV <= 325 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]DAILY MX <= 1453 lb/d May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]DAILY MX <= 1561 lb/d Jan, Feb, Mar, Apr, Nov, Dec
001Nitrite + Nitrate total [as N]MO AVG report only all year
001Phosphorus, total [as P]MO AVG report only all year
001Phosphorus, total [as P]MO TOTAL report only all year
001Phosphorus, total [as P]CUM TOTL <= 21563 lb/yr all year
001Phosphorus, total [as P]ANNL TOT report only Dec
001Hardness, total [as CaCO3]MO AVG report only all year
001Hardness, total [as CaCO3]MO AVG report only all year
001Selenium, total recoverableMO AVG report only Mar, Jun, Sep, Dec
001Copper, total recoverableMO AVG report only all year
001Di[2-ethylhexyl] phthalate [DEHP]MO AVG report only Mar, Jun, Sep, Dec
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Flow, in conduit or thru treatment plantANNL TOT report only Dec
001Chlorine, total residualMX DA AV <= .1 mg/L all year
001E. coliMO GEOMN <= 126 MPN/100mL all year
001Phosphorous, in total orthophosphateMO AVG report only all year
001Flow, totalMO TOTAL report only all year
TRADSolids, total suspendedCUM TOTL report only all year
TRADSolids, total suspendedCUM TOTL report only all year
TRADNitrogen, total [as N]CUM TOTL report only all year
TRADNitrogen, total [as N]CUM TOTL report only all year
TRADPhosphorus, total [as P]CUM TOTL report only all year
TRADPhosphorus, total [as P]CUM TOTL report only all year
TRADFlowYA 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