Big Boulder Habitat Enhancement
January 23, 2012 - 3:22pm | 
staff
GOALS
The goal of the Big Boulder Creek Restoration Project is to protect and enhance existing Chinook salmon habitat in Big Boulder Creek by:
1. Stabilizing 220 feet of the eroding west bank between Big Boulder Creek and adjacent gravel borrow pit 30’ below stream grade.
2. Improving the quality and quantity of aquatic habitat by restoring the natural distributary channel form to the lower reaches of Big Boulder Creek.
3. Enhancing aquatic habitat by installing habitat structure in the distributary channel and Big Boulder Creek.
WORK
Phase One: Work on Phase One was completed July 7 to 15, 2008. A spruce tree revetment was constructed along the west bank of the creek (river right) using root wads, rock, and whole young spruce trees. Native clump and willow plantings were made on the bank behind the revetment. These project components have stabilized the eroding bank preventing escapement into the gravel borrow pit to the west.
A distributary channel was excavated on river left just upstream of the bank stabilization to divert some of higher flows away from the vulnerable bank and to create additional spawning habitat for king salmon. This involved the reestablishment of flow in a former side channel to the east of the main channel. The mouth of this side channel was opened on the bank of the creek 100 ft upstream of the bank protection work. The side channel will provide additional salmon habitat and also function to partially regulate the amount of water in the main channel by reducing peak flow downstream.
Phase Two: Work on Phase Two was completed July 6 to 13, 2010. A total of eight fish habitat structures were installed; two in the main channel, and six in the distributary side channel. Two root wads were installed in the main channel, just upstream of the side channel. Two root wads, two boulder wing deflectors, one boulder dart and one digger log were installed in the side channel. Willow poles were installed in the bank within the structures to aid in further stabilizing the installations.
MONITORING
Monitoring includes several distinct components and is designed to cover both physical and biological aspects of channel adjustments from improvements. The monitoring program will provide information for these purposes:
1. To evaluate the success in meeting the project goals as described above.
2. To provide data that triggers maintenance on the installed structures and;
3. To increase the understanding of the physical and biological characteristics of high quality Chinook salmon habitat as a guide for future enhancement efforts.
