The Nez Perce Tribe wanted to reconfigure a reach of the Red River, making it more natural, and restoring normative stream and floodplain processes.
Careful ecological investigation gave GeoEngineers the data to redesign reaches of the Lower Red River.
GeoEngineers used past meander scrolls to reduce excavation amounts and restore the channel to historic planform.
GeoEngineers re-aligned approximately 1,550 feet of the Lower Red River to accentuate channel planform complexity.
Lower Red River Meadow Stream and Floodplain Enhancement Design
Enhancing river habitat in an important part of the the ecological tapestry of northern Idaho.
Salmon is a vital resource for the Nez Perce Tribe (NPT), and has been for hundreds of years. The tribe has an overarching vision for the restoration and enhancement of the Lower Red River and floodplain in northern Idaho. The NPT wanted to reconfigure a reach of the Red River, making it more natural, and restoring normative stream and floodplain processes.
GeoEngineers worked with the NPT to design these stream and floodplain enhancements. We performed geomorphic and hydraulic analyses, designed a proposed stream alignment with improved floodplain connectivity, and provided a planting plan that was geomorphically-appropriate for the river system.
Approach
GeoEngineers carefully tailored the river designs to enhance natural physical processes. This meant increased biological production and biodiversity for both aquatic and terrestrial species in the project area. To achieve this, the GeoEngineers team:
- Re-aligned approximately 1,550 feet of the Lower Red River to accentuate channel planform complexity
- Utilized past meander scrolls to reduce excavation amounts and restore the channel to historic planform
- Removed a confining berm and numerous historic spoil piles to enhance floodplain connection
- Used native vegetation for long-term stream bank stability and habitat diversification
- Developed the design to be consistent with the HIP III Biological Opinion
- Prepared a Monitoring and Adaptive Management Plan
- Prepared construction specifications
- Performed construction observation during construction
Results
The proposed improvements resulted in enhanced and more diverse aquatic and riparian habitat along the river corridor. This important reach of the Lower Red River is also a piece of the larger project of ecological enhancement, and contributes to the interconnected tapestry of habitat in northern Idaho.
