Wastewater Treatment Plants in Alaska
38 facilities · 22 MGD combined flow
Klarifi tracks 38 publicly owned wastewater treatment plants in Alaska with a combined average flow of 22 MGD, serving about 146,758 residents. 6 plants treat more than 1 MGD and 0 more than 10 MGD; 7 use lagoon systems and 2 have digesters or biogas infrastructure. The largest is Charcoal Point WWTP in Ketchikan at 5.09 MGD. 2 NPDES permits expire this year and 12 next year.
Every plant below links to a profile with average and design flow, treatment technology, the NPDES permit and its expiry, a three-year compliance snapshot and the capital projects planned in its city.
38 plant locations in Alaska; dot size follows average flow.
NPDES permits and renewals in Alaska
Every plant discharges under an NPDES permit that is renewed every five years, usually with tighter limits. The renewal year is the year a plant budgets for upgrades.
Largest wastewater treatment plants in Alaska
| Facility | City | Avg flow (MGD) | Design (MGD) | NPDES permit | Expires | Technology | Violations (3y) |
|---|---|---|---|---|---|---|---|
| Charcoal Point WWTP | Ketchikan | 5.09 | 4 | AK0021440 | Oct 2030 | — | 10 |
| Golden Heart Utilities WWTP | Fairbanks | 4.9 | — | AK0023451 | Dec 2026 | — | 1 |
| Mendenhall Valley WWTP | Juneau | 2.44 | — | AK0022951 | May 2025 | — | 59 |
| Kodiak Wastewater Treatment Facility | Kodiak | 1.5 | — | AK0021555 | May 2029 | Clarifiers, Biogas balloons | 2 |
| Eagle River WWTP | Eagle River | 1.38 | — | AK0022543 | Jan 2031 | — | 0 |
| Sitka Wastewater Facility | Sitka | 1.1 | 5.3 | AK0021474 | Oct 2030 | — | 4 |
| Palmer WWTP | Palmer | 0.63 | — | AK0022497 | Feb 2030 | — | 14 |
| Lowell Point WWTP | Seward | 0.58 | — | AK0021890 | Sep 2027 | Aerated lagoons | 17 |
| Petersburg WWTP | Petersburg | 0.56 | 1.2 | AK0021458 | Oct 2030 | — | 3 |
| Mountain Point Wastewater Treatment Plant | Ketchikan | 0.55 | — | AKG572028 | Dec 2027 | — | 21 |
| Kenai STP | Kenai | 0.43 | — | AK0021377 | May 2026 | Biogas silos, Biogas balloons | 1 |
| Girdwood WWTP | Girdwood | 0.39 | — | AK0047856 | Oct 2005 | — | 6 |
| Homer Public Works Department And WWTP | Homer | 0.38 | — | AK0021245 | Jan 2027 | — | 8 |
| Cordova Wastewater Treatment Plant | Cordova | 0.29 | — | AK0021547 | Feb 2028 | — | 2 |
| Thorne Bay WWTF | Thorne Bay | 0.27 | — | AKG572045 | Dec 2027 | — | 246 |
| Skagway WWTP | Skagway | 0.25 | 0.63 | AK0020010 | Oct 2030 | — | 116 |
| Metlakatla Sewer Treatment Plant | Metlakatla | 0.23 | 0.69 | AK0053813 | Sep 2025 | — | 105 |
| North Pole WWTP | North Pole | 0.16 | — | AK0021393 | May 2013 | — | 4 |
| Spring Creek Correctional Center | Seward | 0.09 | — | AK0053724 | Apr 2027 | — | 67 |
| Auke Bay Wastewater Treatment Facility | Juneau | 0.08 | — | AKG572004 | Dec 2027 | — | 12 |
| Nenana WWTF | Nenana | 0.06 | — | AKG572031 | Dec 2027 | — | 91 |
| Talkeetna Sewage Treatment Lagoons | Talkeetna | 0.06 | — | AKG573033 | Aug 2028 | Uncovered lagoons | 0 |
| King Salmon WWTF | King Salmon | 0.04 | — | AKG573029 | Aug 2028 | — | 53 |
| Seldovia Water System | Seldovia | 0.03 | — | AKG380006 | Sep 2029 | — | 91 |
| Point Hope WWTF | Point Hope | 0.03 | — | AKG571056 | Jul 2009 | — | 211 |
Alaska plants by treatment technology
All 38 plants in Alaska
Wastewater treatment in Alaska: questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed September 11, 2026.