[1][5] Beginning south of Aniak Lake, the river generally flows north.

[5][8][9][16] In addition to salmon, the Aniak is home to Arctic char, rainbow trout, Arctic grayling, and, near the river mouth in spring, northern pike and sheefish, making it a prime sports fishing location.

[17][8][16] Navigation of the river is tricky, since it is swift flowing with multiple channels and many hazards, including debris loads, log jams and sweepers (trees hanging just above the water which "sweep" the surface as it flows by) that change position with each spring's ice breakup cycle.

The upper river, however, is typically only accessed by rafts which can be dropped off by airplane at Aniak Lake,[20] 100 mi (160 km) upstream from the Kuskokwim confluence.

The Aniak River itself, approximately 25 mi (40 km) from the mouth, is unusable for surface travel in winter due to incomplete freeze and speed of flow.