FIP TA: King Slough Alternatives Assessment - Yaquina

This project takes place on the south side of the lower Yaquina estuary, at a site called King Slough. Two undersized road crossings restrict fish passage, tidal flow, and sediment and wood inputs and additionally during the highest tides of the year, the road becomes impassable due to overtopping and is being degraded by this inundation. The issues caused by these tidal barriers will become worse over time as more intense flooding events exacerbate passage issues, as lack of sediment delivery curtails the ability of the tidal wetlands to accrete over time, and as water overtops the road more frequently. This project will conduct engineering design work to produce 100% designs to restore two sections of road and associated culverts crossing King Slough. Project partners are Oregon Department of Fish and Wildlife, Ducks Unlimited, USFWS Coastal Program, Confederated Tribes of the Siletz Indians, and Pacific States Marine Fisheries Commission.

This TA project will allow a suite of alternatives to be explored, with the one selected leading to restoration. The goal is to restore full fish access by removing barriers while also maintaining landowner access to their properties. Upstream of the current road crossings, this TA will also allow planning for tidal swamp and landward migration zone restoration actions, including restoring scrub/shrub and spruce swamp habitat as well as enhancing areas in the landward migration zone to provide shelter, winter refuge, and better opportunities for juvenile salmon growth. The project will benefit chum, coho and Chinook salmon. The importance of quality estuarine habitat is well known for chum salmon. Chum salmon fry move to estuaries soon after they absorb their yolk sacs, and drift throughout the estuary with tidal flows. Restoring access to tidal creeks, sloughs and enhanced marshes provide these fry with vital forage habitat. Coho salmon and Chinook that move into tidal channels and stay for longer periods benefit from rich terrestrial derived as well as aquatic food sources and grow faster, entering the ocean at larger sizes, and returning at higher rates than their freshwater cousins.