crawford creek propertyProject location: Upland Forest
Watershed: Chehalis River Basin Sub-basin: Scatter Creek |
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West Crawford Creek Culvert
Project Description: There was a culvert under an old access road that had a fish passage issue. The culvert was removed to open the channel to its natural state. This access point was no longer needed and the culvert was unnecessary. Once the culvert was removed, washed gravels were placed in the streambed for future use as a crossing if needed.
Completion date: Sept. 1998
Completion date: Sept. 1998
Crawford Creek Culvert Barrier |
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Project description: There was a culvert under an old access road that was a fish passage issue. The culvert was removed and replaced with a bridge. This opened the channel to its natural state. The bridge may have been more expensive than another larger culvert but it would be well worth it to keep the sedimentation from upstream moving through the system. This access point needed to remain or be moved upstream of its current crossing point. Either way a bridge was needed to correct the problem.
An amazing new concrete bridge was installed. Elevating the crossing high above the high water mark during excessive winter flows and elevating all sedimentation issues for the creek allowed normal biological mobility for debris and aquatic wildlife to pass up and down stream of the Crawford Creek tributary. Completion date: Summer 2008 |
crawford creek dam
Project Description: There was an access road into Hidden Meadow that collapsed in the tributary and had created an earthen dam, which was blocking fish passage and sediment from movement throughout the Crawford Creek. The goal was to remove all of the debris that had created this dam/access road and to open the channel so that all aquatic species could move freely throughout this perennial tributary.
The dam had changed the stream channel significantly. Due to the lack of movement, all of the fine sediment, which typically moves through waterways, had settled at the base of the dam. Because of this, the stream bank-full width had 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 had to be taken in to consideration when implementing the project.
The access road was decommissioned and completely removed from the channel. The steep banks were 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 itself 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.
The dam had changed the stream channel significantly. Due to the lack of movement, all of the fine sediment, which typically moves through waterways, had settled at the base of the dam. Because of this, the stream bank-full width had 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 had to be taken in to consideration when implementing the project.
The access road was decommissioned and completely removed from the channel. The steep banks were 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 itself 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.