DESCRIPTION
This is a continuation of the work completed during PRISM project #14-1899. Project Area 11 (PA-11) is located within the active channel and floodplain of the Tucannon R. from RM 41.85 to RM 40.5. PA-11 was identified as a tier 1 project in the Tucannon Conceptual Restoration Plan (Anchor 2011), siting isolated habitats and low LWD compared to the goals in the Salmon Recovery Plan for SE WA (2011). A preliminary design was prepared by WDFW with support from the Tucannon Habitat Programmatic completed in Sept 2014. The project design omit the upper project area channel confining features in and around Beaver Watson Lake to allow for the completion of the Tucannon Floodplain Management Plan, an assessment of the floodplain reservoirs and options to reduce their impacts on the channel. The project goals were to improve and maintain floodplain connectivity and increase channel complexity through the placement of key wood structures and add mobile woody debris. The objectives are to maintain floodplain capacity and increase channel complexity over the 1.56 mile project reach. Project actions include the placement of ~96 woody debris and ELJ type structures. The project is expected to improve winter /summer rearing habitat for ESA listed Snake River spring Chinook, steelhead and winter rearing for Columbia bull trout.
WA Department of Fish and Wildlife (WDFW) increased channel complexity from river mile RM 41.85 to RM 40.5 of the Tucannon River, also known as Project Area 11 (PA-11). Specific project activities included placement of more than 70 large wood complexes using ground equipment in the 1.35 mile main channel and a 0.1 mile side channel. Racking and mobile wood were added to provide additional wood recruitment to the log complexes. 1000 cottonwoods and 700 Ponderosa pine trees were planted in priority areas along the side channel and in staging areas disturbed during construction. WDFW intends to plant additional trees in this river reach in the near future, outside of the grant.
PA-11 i was identified as a tier 1 project area in the Tucannon Conceptual Restoration Plan (Anchor 2011), siting isolated habitats and low wood abundance compared to the goals in the Salmon Recovery Plan for SE WA (2011). Designs for instream construction were prepared in house by WDFW with support from the Tucannon Habitat Programmatic. The objectives were to maintain floodplain capacity and increase channel complexity over the 1.35 mile project reach. The project has increased floodplain connection at a faster rate than we anticipated, but because the project is located on a State Wildlife Area, that has not been a problem. Multiple side channels and high flow channels were re-established as a result of the project. The project is expected to improve winter/summer rearing habitat for ESA listed Snake River spring Chinook, steelhead, and winter rearing for Columbia Bull Trout.