Lagoon systems: wastewater treatment plants in Alaska
10 plants · 26% of the state · 3 MGD reported by 5 plants
Klarifi identifies 10 publicly owned wastewater treatment plants with lagoon systems in Alaska, 26% of the 38 plants in the state (3 MGD reported by 5 plants). The largest is Eagle River WWTP in Eagle River at 1.38 MGD.
Lagoon systems treat wastewater in large earthen ponds over weeks of retention time, with or without mechanical aeration. They serve thousands of small towns because they are cheap to run, but they struggle with ammonia and nutrient limits, fill with sludge over decades and are the plants most often converted or upgraded when a permit is renewed.
The largest lagoons in Alaska
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | Eagle River WWTP | Eagle River | 1.38 | AK0022543 | Jan 2031 | 0 |
| 2 | Lowell Point WWTP | Seward | 0.58 | AK0021890 | Sep 2027 | 17 |
| 3 | Girdwood WWTP | Girdwood | 0.39 | AK0047856 | Oct 2005 | 6 |
| 4 | North Pole WWTP | North Pole | 0.16 | AK0021393 | May 2013 | 4 |
| 5 | Talkeetna Sewage Treatment Lagoons | Talkeetna | 0.06 | AKG573033 | Aug 2028 | 0 |
| 6 | Alakanuk Lagoon | Alakanuk | — | AKG573001 | Aug 2028 | — |
| 7 | Buckland Sewage Lagoon | Buckland | — | AKG573028 | Aug 2028 | — |
| 8 | Chuathbaluk Wastewater Lagoon | Aniak | — | AKG573002 | Aug 2028 | — |
| 9 | Dillingham WWTP | Dillingham | — | AKG573004 | Aug 2028 | 115 |
| 10 | Mountain Village Lagoon | Mountain Village | — | AKG573031 | Aug 2028 | 3 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
Other technologies in Alaska
Lagoon systems in other states
Lagoon systems 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.