South Fork Pedee Creek Enhancement

The South Fork Pedee Creek Enhancement project area lies within the timberlands of the upper Luckiamute watershed in the Pedee 6th field hydrologic unit. The North and South Forks join to form Pedee Creek, which then drains into the Luckiamute River near the community of Pedee in Polk County. Historical practices such as logging to the waters edge, log removal, and log drives impacted upper Luckiamute sub-basins, including Pedee. This project will: 1) replace two undersized culverts with bridges to improve access to upstream habitat and restore sediment transport processes; 2) install large wood structures to increase bedload retention and improve channel-floodplain interaction; and 3) plant and treat invasive plants to re-establish the riparian forest located along the project reach and to provide a source of future instream large wood.
Because the projects scheduled end date is after the PCSRF FFY 2018 award closes, no funds allocated for this project are reported as match to PCSRF funds.

The likelihood that restoration investments in degraded aquatic systems will be effective depends upon two factors: first, whether locations have the intrinsic potential to provide high quality habitat (e.g. gradient, stream size, valley constraint, gravel and sediment) and second, whether the forest-cover conditions needed to sustain recovery of high-quality habitat are present or possible (Burnett and Miller 2011).

Rapid Bio-Assessment (RBA) surveys conducted across the Luckiamute watershed from 2008-2011 identified steelhead in the Pedee sub-basin in 2008 - 2010, specifically in S.F. Pedee in 2009. The RBA report describes the Pedee sub-basin as one of the top three priority zones for restoring system function and enhancing both anadromous and resident salmonid populations. The report also notes observations and survey data suggest S.F. Pedee and the upper 3 miles of NF Pedee exhibit the highest potentials for anadromous salmonid production in the Pedee Cr. sub-basin (Luckiamute RBA Final Report, 2011, Bio-Surveys, LLC, pg. 8). While historical practices have impacted S.F. Pedee Creek, the LWC is confident that intervention will successfully restore ecological processes and enhance habitat.

In addition to the RBA report prioritizing this area for restoration, the LWC completed a technical assistance grant (216-3016) that supported a project planning and prioritization effort. The LWC used NetMaps fine scale analyses and tools to identify stream reaches in the watershed that demonstrate highest potential for providing high quality salmonid habitat, termed anchor habitats. The LWC uses the term anchor habitat here to indicate those specific stream reaches that have maximum intrinsic potential for high quality salmonid habitat and where there is evidence of existing salmonid populations. These reaches are identified as priority focal areas for protection and restoration. S.F. Pedee received the highest anchor habitat score in that analysis. Follow-up ACH field verification and surveying conducted by the LWCs Project Manager and BLM Marys Peak Field Office Hydrologist and Fish Biologist confirmed that South Fork Pedee Creek exhibits the key geomorphological features and water quality conditions that make it ideal for steelhead, coho, and cuthroat. By resolving two undersized culverts and implementing reach-scale large wood placement along 2.1 miles, conifer enrichment, and riparian reforestation, the proposed intervention will catalyze recovery of S.F. Pedee to provide high quality salmonid habitat in the Luckiamute watershed.

Constructed large wood structures are expected to retain bedload. This aggradation lifts the elevation of the active channel to increase the frequency of floodplain interaction. The retention of bedload will also: 1) increase summer pool complexity by forming a gravel bed on bedrock for the development of deep pool scour (Roni et al. 2015); 2) reduce the direct warming influence of air and solar exposure through reduction of exposed bedrock; 3) increase floodplain storage of ground water to mitigate for elevated summer stream temps (Hester et al. 2009); 4) provide a platform for robust macroinvertebrate production (Gregory et al. 1991); 5) enable the recolonization of dam building beaver that can utilize the log structures for a stable dam foundation that is winter-persistent (NOAA 2014). Restoring riparian conditions will provide needed canopy cover, future large wood sources, and nutrient inputs for the aquatic food web.