Washington Aqueduct

NPDES permit MD0068161 · Minor NON-POTW · effective, expires 2031-08-31 · 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.

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

EPA's file shows no filings for this permit in this window. That is a statement about the file, not about the facility.

Reporting

Reports are due about 28 days after each monitoring period ends (the most common figure among MD permits in EPA's filings — check your permit).

Limits in force (26)

OutfallParameterStatisticLimitMonths
005Oxygen, dissolved [DO]MINIMUM >= 5 mg/L all year
005pHMINIMUM >= 6.5 SU all year
005pHMAXIMUM <= 8.5 SU all year
005Solids, total suspendedMX MO AV <= 20 mg/L all year
005Solids, total suspendedDAILY MX <= 30 mg/L all year
005Aluminum, total recoverableMX MO AV <= .46 mg/L all year
005Aluminum, total recoverableDAILY MX <= .69 mg/L all year
005Flow, in conduit or thru treatment plantMO AVG report only all year
005Flow, in conduit or thru treatment plantDAILY MX report only all year
005Chlorine, total residualMX MO AV <= .011 mg/L all year
005Chlorine, total residualDAILY MX <= .019 mg/L all year
501pHMINIMUM >= 6.5 SU all year
501pHMAXIMUM <= 8.5 SU all year
501Solids, total suspendedMX MO AV <= 20 mg/L all year
501Solids, total suspendedDAILY MX <= 30 mg/L all year
501Aluminum, total recoverableMX MO AV <= .46 mg/L all year
501Aluminum, total recoverableMAXIMUM <= .69 mg/L all year
501Flow, in conduit or thru treatment plantMO AVG report only all year
501Flow, in conduit or thru treatment plantDAILY MX report only all year
502Oxygen, dissolved [DO]MINIMUM >= 5 mg/L all year
502pHMINIMUM >= 6.5 SU all year
502pHMAXIMUM <= 8.5 SU all year
502Flow, in conduit or thru treatment plantMO AVG report only all year
502Flow, in conduit or thru treatment plantDAILY MX report only all year
502Chlorine, total residualMX MO AV <= .011 mg/L all year
502Chlorine, total residualDAILY MX <= .019 mg/L 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