Cardno was contracted by Environmental Troubleshooters (ET) to provide technical guidance and support to the Lake Superior Steelhead Association’s (LSSA) effort to complete a stream design and construction project on the Knife River in Lake County, Minnesota. First, Cardno assessed 7,000 feet of stream, including 2,000 feet of channel which was used as reference reach data to guide the design process.
Cardno led the stream design process to address the following goals:
- Improve summer and overwintering habitat to increase the number of young fish staying in the Knife River to the age of 2+ years-old.
- Improve and increase the distribution of spawning habitat throughout the reach.
- Reduce erosion along banks contributing to habitat degradation throughout the reach and downstream.
Cardno, with support from ET staff, collected geomorphic data at the stream reach level including:
- Stream profile
- Representative crossing sections
- Pebble counts
- Other forms associated with a Level III Assessment in the Natural Channel Design (NCD) assessment methodology
Following field work, Cardno analyzed the data in RIVERMorph™ and classified each reach based on Rosgen’s Classification of Natural Rivers. Cardno then developed the design for approximately 5,000 feet of stream channel from the assessment and reference reach data in a manner consistent with the NCD principles.
Staff provided on-site construction supervision and support to ET to construct approximately 600 feet of stream work, the first phase of the multi-year construction project. Three sections of toewood along with J-hook log vanes and constructed riffles were installed.
The next phase of the project will focus on stabilizing banks, creating deep pool habitat, and re-meandering several sections of stream channel to avoid eroding banks and promoting a more stable dimension, pattern, and profile.