Sediment transport in the Tanana River near Fairbanks, Alaska, 1982

Suspended-sediment and bedload-transport rates for the Tanana River near Fairbanks can be related to water discharge, and annual sediment loads can be computed using these relations. For a site at Fairbanks the annual loads in 1982 were 26.1 million metric tons of suspended sediment and 227,000 metric tons of bedload. Data collected at five other sites within a 40-kilometer reach of the river indicate similar suspended-sediment-transport relations but bedload-transport relations varied from site to site. For all sites bedload is about 1 percent of suspended-sediment load. Particle-size distribution of suspended sediment is similar at all six sites. Median particle size is generally in the silt range; only occasionally is it in the very fine sand range. Median particle size of bedload ranged from the gravel range to the medium sand range at four of the six sampling sites. At the farthest downstream site, Byers Island, and the farthest upstream site, above Chena River Floodway, median particle size of bedload was always in the sand range. (USGS)