Finalizing Floodplain Restoration Designs & Permitting for Elijah Bristow State Park - Phase 1

The Middle Fork Willamette Watershed Council (MFWWC) contracted Wolf Water Resources (W2r) to support the Elijah Bristow State Park (EBSP) Floodplain Restoration Project. Wolf Water Resources took the lead on design development for the project with input and guidance from MFWWC, Oregon Parks and Recreation Department, the EBSP Technical Team, and the Community Advisory Committee. W2r also supported the MFWWC in their engagement with the US Army Corps of Engineers (USACE, Corps) to determine if the Section 408 process is the appropriate avenue to address relocating a USGS stream gauge and removing or altering a USACE levee within the project area which are crucial steps to design development and future implementation. 30% design iterations for the Upper Zone project area were achieved, which determined that a Conditional Letter of Map Revision submitted to FEMA will be necessary for the project, and Section 408 Alteration Determination Applications were submitted to the Corps for stream gauge relocation, levee removal, and a fill removal action on USACE owned property that came up during the design process. It was determined that the stream gauge and fill removal actions were better suited for the Corps Real Estate department review and subsequently SF 299 forms were submitted for their review. The levee removal or alteration actions through Section 408 are still being reviewed and discussed between the Corps, the Middle Fork Willamette Watershed Council, Oregon Parks and Recreation Department, and Wolf Water Resources, and this effort is continued in Phase II of this effort.

EBSP currently provides habitat for spring Chinook salmon. Salmon and steelhead need a diversity of habitat to satisfy needs within their various life stages. Currently, the project area lacks dynamic off-channel, side channel and slow water habitat which are important for spawning, rearing and protection from high flows. Large wood is infrequent within the project area. Due to the location below the dams, the lower Middle Fork Willamette River is also starved of gravel. If degradation of this site continues, it will negatively impact these spring Chinook salmon and other species. The floodplain restoration design that will result from this Technical Assistance project will identify how to increase the frequency and quality of floodplain connectivity, elevate the water table, connect side channels and alcoves, and mobilize trapped sediments. By restoring these processes, the habitat will follow, benefitting salmon and steelhead at all life stages.