Project Description: – There is an access road into Hidden Meadow that has collapsed in the tributary and created an earthen dam, which is blocking fish passage and sediment movement throughout the Crawford Creek. The goal is to remove all of the debris that has created this dam/access road and open the channel so that all aquatic species can move freely throughout this perennial tributary.
The dam has changed the stream channel significantly. Due to the lack of movement, all of the fine sediment, which typically moves through waterways, has settled at the base of the dam. Because of this, the stream bank-full width has widened significantly, killing the surrounding riparian trees and depositing several feet of sediment, raising the streambed on the upstream side of the dam. This elevation difference now has to be taken in to consideration when implementing the project.
The access road has been decommissioned and completely removed from the channel. The steep banks have been pulled back to a 2% grade and covered with coconut matting to prevent additional sediment delivery until the vegetation regenerates.
We will give the channel a couple of years to flush its self and move sediment and debris as needed with winter high flows. Once the elevation grade has stabilized we can then re-asses the streambed migration and address any further issues.
Watershed: Chehalis River Basin Sub-basin: Scatter Creek Tributary: Crawford Creek