Channel Changes Slide 12
Tanana River’s main channel past the junction of the Chena River shown in dashed red line on August 27, 1996 image.
Between 2004 and 2010 (8-14 years after this 1996 Ortho Quad image) the main channel of the Tanana River abandoned its sinusoidal course in favor of a storm-drain straight shot westward alongside the U.S. Army Corps of Engineer's (USACE) groin used as a gauging station, then through the deeply excavated gravel pit, bisecting Byers Island, and directing its main flow at the base of the Chena Ridge bluff.
Especially in 2010-2013, the true confluence of the Chena River (clear water) and Tanana River (silty water) had moved from its traditional mouth (1) to downstream of the boat launching ground at the old townsite of Chena (2). The old channel between (1) and (2) was becoming shallow and meandering, making navigation challenging for the mile and a half (2 km) between the two points.
Satellite image from the Geodata Center, Geophysical Institute, University of Alaska Fairbanks.