Swaner Preserve Riparian Ecosystem Restoration
Project Goals and Objectives
We sought to alter the ecosystem function of East Canyon and Kimball Creeks through adding structural elements to modify the geomorphic and ecological processes which were preventing the stream from naturally recovering from a degraded state brought about by over a hundred years of agricultural landuse. Specifically, our restoration goals were to provide thermal refugia for a variety of native fish species, enhance the amount of dissolved oxygen within the water column, improve the rates of establishment and growth for woody riparian vegetation, and reconnect the channel to its floodplain during all flow conditions. Since multiple beaver colonies can be found within ~2km of the restoration sites, we opted to let beaver naturally disperse to our sites over time as the habitat improves for them
Structure Construction Elements
We built about 20 large beaver dam analogs (BDAs) averaging over 5 meters in width. Our structural design utilized 3in diameter fence posts, local cobble/gravel/mud/willows, and old Christmas trees as primary materials. We built a variety of BDA types including primary, secondary, channel-spanning, and construction dams to achieve our restoration goals. About 5 post-assisted log structures (PALs) were built using old Christmas trees and 3in diameter fence posts. Bank attached, mid-channel, and channel spanning PALs were used in this project.
Project Photos
Cover Photo