Horsetail Creek, in the Columbia River Gorge, was historically a dynamic part of the Columbia River floodplain with an ash forest, willow bottoms, and five creeks and sloughs connecting to the river, providing important habitat for salmon, steelhead and lamprey. The area is important, as quality floodplain habitat is scarce and for out-migrating salmon, the Horsetail floodplain is one of the last spots to rest and feed before traveling through the Portland-Vancouver Metro area where such habitat is severely limited. In 2013, the Estuary Partnership worked with the US Forest Service and other partners and contractors to restore connectivity and 180 acres of habitat at the site.
The site had several issues. The construction of Interstate 84 and the railroad line cut the floodplain off from the mainstem Columbia River, and habitat was further degraded when people cleared the land to graze cattle. Though there was a culvert, it was too small and only accessible by fish when the Columbia River was high. Fish could also be stranded when river levels receded. Moreover, when the highway was constructed, there was a gravel pit left behind that nearby Oneonta Creek had diverted through before it flowed into Horsetail Creek. This still water raised temperatures throughout the site.
Through the project, we worked with crews from Aquatic Contracting to retrofit the culvert that passes under I-84 to make it easier for salmon and lamprey to access the site. We also eliminated the diversion of Oneonta Creek and converted the former gravel pond to native wetland habitat. Crews from Ash Creek Forest Management also removed invasive species and revegetated the area with native trees and shrubs. Helicopters flew in and placed 600 large logs and root wads in the streams and wetlands. Design, engineering and construction oversight was by Inter-Fluve.
Many species have been observed at the site, including coho, steelhead, and Chinook (including stocks from eastern Oregon, Washington, and Idaho), red-legged frogs, great blue heron, and other wildlife.
In 2017, the Estuary Partnership and the US Forest Service began scoping for a second phase of floodplain restoration at this site, to the east of the first phase's project area. The plan is to fell large trees onto the floodplain to increase habitat complexity and restore native vegetation to another 30 acres of floodplain and riparian habitat. In fall of 2017, the Eagle Creek Fire burned through the Columbia River Gorge and impacted approximately 16 acres at this site, making revegetation efforts even more critical. In early 2020, Phase II leveraged trees burned in the fire by felling them, along with some live trees, into the stream and onto the floodplain. Future Phase II activities will see crews treating invasive reed canarygrass and planting 65,000 native trees and shrubs.
Thanks for Sara Fox for developing a video for the project.
Actual Miles Restored