Earthmoving at Wasson Creek

The South Slough Reserve may not be moving mountains, but it did move an impressive amount of earth last summer! As part of the Wasson Creek Ridgetop-to-Estuary Restoration, they’ve transformed the creek into a “Stage Zero” landscape. What was once a narrow creek channel surrounded by steep invasive species is now a graded valley floor, designed to encourage native species regrowth and natural water flow and wetlands. Congratulations, and thanks, to staff and interns from the Reserve, Oregon’s Bureau of Land Management, the Coos Watershed Association, the Northwest Watershed Restoration, and the many volunteers who made this progress possible. 

How did they get to Stage Zero in just two short months? Well …

They set the scene. Before the work began, the team installed time-lapse cameras to capture the creek’s changes from different angles.

They did a lot of pre-restoration monitoring. Extensive monitoring informed every step of the work. For example, lamprey monitoring helped them relocate and return the fish, and groundwater sampling indicated the driest time of year for construction.

They took a cue from beavers. To encourage the return of wetlands, the team installed Beaver Dam Analogs (BDAs) that had been built with guidance from the Kachemak Bay Reserve.

It being summer, they did a bunch of mowing. Before they could start moving earth, the team had to mow acres of invasive reed canary grass.

Then came the heavy equipment. Stage Zero restoration guidelines called for regrading the valley to a 1% slope, which allows water flowing across the valley to develop its own flow pathways.

And some fine tuning: Target elevation map and Real-Time Kinematic (RTK) satellite data to help the team get the slope just right. 

They planned for flow. By placing large wood structures, they slowed the stream flow and created conditions for a wetland-stream complex to develop.

They moved a bunch of critters! The team relocated 9,897 fish and salamanders from the ditched channel to healthier streams as part of the fish salvage effort. Species included cutthroat trout, Coho, Pacific giant salamanders, and more.

They redirected the water by filling in the ditched stream and diverting it to the newly graded wetland surface.

Then they reduced the sediment input to streams. They spread weed-free straw for erosion control.

They planned for habitats by constructing nurse cribs to support planting tidal forested swamp species …

And native plant restoration by collecting and spreading native seeds …

And planting wetlands with live willow cuttings and other native plants.

They practiced co-stewardship with the Confederated Tribes of the Coos, Lower Umpqua and Siuslaw Indians, and the Coquille Indian Tribe.

It was a phenomenal team effort that included many interns including those pictured here: Fiona Carey, Connie Hua Zhang, and Ingrid Fellows, who played a vital role throughout the project …

And amazing leadership from the Reserve’s Stewardship Coordinator Dr. Alice Yeates—who needs excavators?

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