Nason Crk RM 12 Floodplain Reconnection

This project evaluated the mainstem channel and adjacent floodplains on river left and right (~RM 12.0-11.5) to identify and develop restoration actions that will improve in-stream conditions and reconnect the floodplain. We completed work necessary to evaluate the site, developed and analyzed alternative restoration strategies and prepared conceptual and preliminary designs for the preferred alternative (these were uploaded to PRISM). We hired a contractor to complete tasks including on-site data collection (land survey, characterization of in-stream and wetland habitats, etc.), compilation of existing data, hydraulic modeling, opportunities and constraints analysis, and development of conceptual and preliminary engineering designs (and oversaw and assisted in the process).

The project goal is to collect data on existing conditions, evaluate potential restoration actions and develop Conceptual and Preliminary designs for the project area.

Potential restoration actions developed and reviewed during this phase of the project mimic the structure and complexity provided in natural systems. They included engineered log jams, constructed rock/log riffles, and side channel excavation.

The design strategy is to:
• Increase habitat complexity and pools.
• Recruit wood and channel forming substrate.
• Reconnect disconnected side channels and floodplain habitats (disconnected by channel incision).
• Promote stream/side channel shading and/or narrowing to reduce solar heating.


Goal 1: Increase quantity and quality of adult holding and spawning habitats.

Goal 2: Increase quantity and quality of juvenile rearing habitat.

Goal 3: Improve floodplain connectivity to improve aquatic habitat quality, water storage, and riparian health.

Goal 4: Reduce stream temperature impacts