SITKA, CITY AND BOROUGH OF

NPDES permit AK0021474 · Major POTW · effective, expires 2030-10-31 · EPA's file as of 2026-09-26

Keep this permit as a site — opens New site at EPA's facility point (57.046724, -135.353486); you set the radius.

These are the last limits EPA's file holds for this permit, from an earlier version of it (version 0 in EPA's file): its current version carries none yet. Read your permit: a renewal can change them.

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

Last period with anything received: 2026-08-31. Most often over: Oxygen, dissolved [DO] (4), Coliform, fecal, colony forming units (2), Solids, total suspended (1).

Reporting

Reports are due about 15 days after each monitoring period ends (the most common figure among AK permits in EPA's filings — check your permit).

• Outfall 001, form A (Middle Channel of Sitka Sound Interim Limits): every 1 month(s), 33 values
• Outfall 001, form S (PFAS): files for periods ending in Mar, Jun, Sep

How strict are these limits?

Each concentration limit against the same limit in comparable permits. Where it appears more than once, its strictest value.

• pH, instantaneous maximum 8.5 SU — stricter than 91% of 613 other major POTWs nationwide; 8% have the same limit
• pH, instantaneous minimum at least 6.5 SU — stricter than 86% of 607 other major POTWs nationwide; 13% have the same limit
• Oxygen, dissolved [DO], instantaneous minimum at least 6 mg/L — stricter than 59% of 601 other major POTWs nationwide; 19% have the same limit
• Solids, total suspended, monthly average 58 mg/L — stricter than 2% of 3357 other major POTWs nationwide
• Solids, total suspended, weekly average 73 mg/L — stricter than 2% of 2056 other major POTWs nationwide
• Nitrogen, ammonia total [as N], daily maximum 53 mg/L — stricter than 2% of 1661 other major POTWs nationwide
• Copper, total recoverable, daily maximum .241 mg/L — stricter than 1% of 51 other major POTWs nationwide
• Nitrogen, ammonia total [as N], monthly average 35 mg/L — stricter than 1% of 2309 other major POTWs nationwide; 1% have the same limit
• BOD, 5-day, 20 deg. C, monthly average 151 mg/L — stricter than 0% of 1449 other major POTWs nationwide
• BOD, 5-day, 20 deg. C, weekly average 196 mg/L — stricter than 0% of 1050 other major POTWs nationwide
• Copper, total recoverable, monthly average .11 mg/L — stricter than 0% of 68 other major POTWs nationwide
• Solids, suspended percent removal, monthly average minimum at least 30 % — stricter than 0% of 1528 other major POTWs nationwide
• BOD, 5-day, percent removal, monthly average minimum at least 30 % — stricter than 0% of 838 other major POTWs nationwide; 1% have the same limit

3 other limits: fewer than 20 comparable permits.

Limits in force (39)

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