Monitoring Fine Sediment: Grande Ronde and John Day Rivers, 2004 Final Report
Fine sediment trends were evaluated by monitoring percentage surface fine sediment as well as fine sediment infiltration into cleaned spawning gravels embedded into spawning reaches in plastic buckets. The threshold fine sediment particle size was ≤ 6.35 mm; however, fines were recorded in three size fractions-0.0-0.85 mm, 0.85-2.0 mm, and 2.0-6.35 mm.
Overwinter fine sediment (for fines
Statistical comparison of 4-year mean overwinter fines infiltration among study streams revealed that for fines
Other studies have shown that surface fine sediment levels are significantly related to average survival-to-emergence of Chinook salmon. Also, surface fine sediment levels tend to indicate fines levels that would be equaled or exceeded in the subsurface spawning gravels, thereby representing a minimal estimate of conditions to which eggs/alevins are subjected.
McCullough, D., and M. Greene. 2006. Monitoring Fine Sediment; Grande Ronde and John Day Rivers, 2001-2003 Final Report. Project No. 199703400, 166 electronic pages, (BPA Report DOE/BP-00004272-2)