PA-3: Instream Habitat, Contract # 62642

In 2012, CTUIR initiated the design and development of PA-3 between RM 46.75 & RM 48.1 located on the WDFW Wildlife Area and USFS properties using a combination of CTUIR and Programmatic funding. A small section of the upper project, above the confluence of the Little Tucannon was excluded from the project design to avoid an existing habitat monitoring control site identified under the Tucannon CHaMP. The project design was completed and reviewed by the Programmatic and landowners in 2013, and implementation took place in July 2014. The project objectives were to increase channel complexity, off channel, side channel habitat and floodplain connectivity, through the placement of LWD. The project was designed to place large wood instream using a Vertol 107 helicopter in single and multiple tree configurations (Figure 15 & 16). This method was selected due to limited site access and the proximity of whole trees to the project area, which were donated by the USNF. The use of whole unanchored trees allows for a more natural habitat design and we believe a more natural river process. To provide downstream security below the unanchored wood, 5 engineered structures ballasted with large rock, were built to provide overall project stability and act as a backstop preventing mass movement of wood from the project area into high use areas (Figure 17).

The project placed 324 whole trees key pieces (>6m long & 0.3m dia), 21 logs (>6m long &0.15 > 0.3m dia) via helicopter and conventional equipment in numerous configurations at 42 locations over the 1.36 mile project reach (Appendix A). The project increased the total number of LWD key pieces (>6m long & 0.3m dia) from 101 pre-project to 393 post project, an increase of 289% (Table 12). To provide stability to the five lower structures 106 boulders were used to ballast the five structures (Figure 17). Predicted project restoration metrics were provided by Anchor 2011 Nov (Table 3), and final implementation metric are provided in Table 10 produced from rapid surveys.

The Programmatic worked to pair the project implementation with a pre-project CHaMP monitoring site (Figure 16) and AME fish monitoring, post project surveys will be completed in upcoming years. Data is available at monitoringdata.org or through coordination with the Tucannon CHaMP monitoring program.