Upper Occoquan Service Authority

NPDES permit VA0024988 · Major POTW · effective, expires 2028-09-30 · EPA's file as of 2026-09-19

Check this month's numbers before you file

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

0values over a limit
0required values missing, on 0 form(s)
0of 14 forms filed late

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

Reporting

Reports are due about 10 days after each monitoring period ends (the most common figure among VA permits in EPA's filings — check your permit).

Limits in force (25)

OutfallParameterStatisticLimitMonths
001TurbidityMO AVG <= .5 NTU all year
001Oxygen, dissolved [DO]INST MIN >= 5 mg/L all year
001Oxygen demand, chem. [low level] [COD]MO AVG <= 10 mg/L all year
001Oxygen demand, chem. [low level] [COD]WKLY AVG <= 25 mg/L all year
001Oxygen demand, chem. [low level] [COD]MO AVG <= 2000 kg/d all year
001Oxygen demand, chem. [low level] [COD]WKLY AVG <= 5100 kg/d all year
001pHMINIMUM >= 6 SU all year
001pHMAXIMUM <= 9 SU all year
001Solids, total suspendedMO AVG <= 1 mg/L all year
001Solids, total suspendedWKLY AVG <= 2.5 mg/L all year
001Solids, total suspendedMO AVG <= 200 kg/d all year
001Solids, total suspendedWKLY AVG <= 510 kg/d all year
001Nitrogen, Kjeldahl, total [as N]MO AVG <= 1 mg/L all year
001Nitrogen, Kjeldahl, total [as N]WKLY AVG <= 2.5 mg/L all year
001Phosphorus, total [as P]MO AVG <= .1 mg/L all year
001Phosphorus, total [as P]WKLY AVG <= .25 mg/L all year
001Surfactants [MBAS]MO AVG <= .1 mg/L all year
001Surfactants [MBAS]WKLY AVG <= .25 mg/L all year
001Flow, in conduit or thru treatment plantMO AVG <= 54 MGD (alert) all year
001Flow, in conduit or thru treatment plantDAILY MX report only (alert) all year
001Chlorine, total residualMO AVG <= .008 mg/L all year
001Chlorine, total residualWKLY AVG <= .01 mg/L all year
001E. coliMO GEOMN <= 2 #/100mL all year
001TU Static Renewal 7-Day Chronic Ceriodaphnia dubiaWKLY AVG report only all year
001TU Static Renewal 7-Day Chronic Pimphales promelasWKLY AVG 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