River Restoration at Oxbow Regional Park and Dabney State Recreational Area
The Sandy River is confined by steep valley walls and is very dynamic, with variable high flows and extremely erodible soils. Because of the fine-grained sediment, the Lewis and Clark expedition names it the "Quick Sand River".
Needing to improve habitat and protect recreational infrastructure on properties owned by Metro Parks and Greenspaces and the Portland Water Bureau, W2r was hired to develop restoration designs for floodplain, channel, and wetland habitats for sites at Oxbow Regional Park and Dabney State Recreational Area. These sites are located roughly 10 miles upstream of the Sandy River confluence with the Columbia River.
Natural Systems Design was a key partner on the design of engineered log jams for the PWB Oxbow portion of the project.
Inherent to W2r's engineering approach was designing as nature would. This meant understanding the river could not be fixed into one position and the design must allow the river to maintain natural procsses and channel change while also creating certainty of project outcomes for project stakeholders.
Restoration actions included enhancing two side channels, placement of large wood for habitat enhancements and flow redirection, creating an emulated landside to enhance habitat, and restoration of riparian areas.
Client
Metro and Portland Water Bureau
Keywords
Bank stabilization, engineered log jams, wood habiat structures, side channel enhancement, emulated landslide, riparian enhancement, geomorphic assessment, hydrologic and hydraulic modeling
