Umpqua River Oregon North Umpqua PhotoMosaic 1939

The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of Reedsport. In cooperation with the Portland District of the U.S. Army Corps of Engineers (USACE), the USGS evaluated sediment transport and gravel storage along the downstream alluvial reaches of the North and South Umpqua Rivers and the entire mainstem Umpqua River. This includes the lower 46.8 kilometers (29.1 miles) of the North Umpqua River and the lower 122.6 kilometers (76.2 miles) of the South Umpqua River. The Umpqua River gravel transport study involved multiple analyses, including tracking patterns of historical channel change and estimation of a sediment budget. [...]

乌姆普夸河（Umpqua River）的流域面积达12103平方千米（4673平方英里），流经俄勒冈州西南部，最终在里德斯波特市附近的温彻斯特湾注入太平洋。本研究与美国陆军工程兵团（U.S. Army Corps of Engineers, USACE）波特兰分局合作开展，由美国地质调查局（U.S. Geological Survey, USGS）对北乌姆普夸河、南乌姆普夸河下游冲积河段以及乌姆普夸河全干流的泥沙输移与砾石储存情况进行评估。本次评估覆盖范围包括北乌姆普夸河下游46.8千米（29.1英里）河段，以及南乌姆普夸河下游122.6千米（76.2英里）河段。乌姆普夸河砾石输移研究涉及多项分析工作，包括历史河道变化格局追踪与泥沙预算估算等[...]