Draft permit would let Fairbanks discharge 11.2 million gallons a day into the Tanana

Up to 11.2 million gallons of treated sewage a day could keep flowing into the Tanana River under a draft permit the Alaska Department of Environmental Conservation posted Sept. 8. The permit would let the city of Fairbanks and Golden Heart Utilities continue discharging secondary treated sewage from their jointly operated wastewater plant, with a mixing zone that allows water quality limits to be exceeded near the outfall.

The mixing zone covers total ammonia as nitrogen, copper, temperature and whole effluent toxicity. It sets a chronic dilution of 13.4 to 1 and an acute zone at 4.1 to 1. Effluent limits include monthly averages of 25 milligrams per liter for carbonaceous biochemical oxygen demand, known as CBOD5, and 30 milligrams per liter for total suspended solids. The permittees would run annual toxicity tests, inspect industrial users and post a sign on the riverbank.

The 11.2 million-gallon ceiling is not new. It rose from 8.0 million gallons in the 2015 draft, and a 2021 proposed final permit kept the higher cap. DEC's 2024 priority list identified two Tier 1 projects totaling $6.7 million to install ultraviolet disinfection so the plant can meet lower chlorine limits, work that would affect both effluent quality and sewer costs for Golden Heart Utilities customers.

State policy requires mixing zones to stay as small as practicable. They cannot create a public health hazard or harm aquatic life, and salmon spawning areas carry added limits. Environmental groups and some Alaska tribes argue the zones concentrate contaminants in habitat that downstream users rely on. DEC calls them a regulated tool to protect water uses.

The 10-day applicant review ran Aug. 20 through Sept. 2, 2026, closing before DEC posted the Sept. 8 draft. The notice said, "DEC will prepare a draft permit and fact sheet for a formal 30-day public review period." DEC has not announced comment dates. Marie Klingman is the department contact. The documents describe a permit review, not an enforcement action, lawsuit or operational failure.