Three Rivers Weir

Oregon’s “Salmon Superhighway”

About the Project

Three Rivers Weir is a concrete and steel structure, 50 feet wide by nine feet high, that stretches across the Nestucca River, which flows along Oregon’s north coast. Part of the Cedar Creek Fish Hatchery, operated by the Oregon Department of Fish and Wildlife (ODFW), the weir has pickets designed to prevent hatchery fish from swimming upstream and spawning with wild salmon and steelhead (wild fish are collected and released upstream of the weir). The system is ineffective. Hatchery fish can move upstream around the pickets during very high flows, while wild fish cannot pass during low flows, effectively blocking 14 miles of high-quality spawning and rearing habitat for salmonids and lamprey.

ODFW is replacing the picket system with an Obermeyer weir, which has an inflatable pneumatic bladder to block passage at appropriate times. The new system will remove the barrier for wild fish, allowing salmonids to access higher elevation spawning and rearing habitat after relatively short river-mile migrations.

The work unfolds as part of the Salmon Superhighway Initiative which seeks to open 178 river miles in Oregon’s Tillamook and Nestucca River systems. The initiative’s community partnership has surveyed and classified barriers, estimated costs of remediation for each, and evaluated the relative value of opening obstructed river habitat for six species of salmon and steelhead.

FACTS AT A GLANCE
Owner: Oregon Department of Fish and Wildlife
Size: 50 feet wide, 9 feet high
Project Cost: $2 million
ORF Investment: Construction
Miles Opened: 14 miles
Fish: Coho, fall and spring Chinook, cutthroat trout, Pacific lamprey, western brook lamprey, winter steelhead
Status: Dam removal anticipated in 2021


RESOURCES
OUTCOMES
  • Improve river access to 14 miles of spawning and rearing habitat
  • Allow fish passage for wild fish during winter months
  • Improve staff safety and intensity of ODFW’s trap, sort, and pass system
  • Reduce maintenance needs of an aging system
  • Enable additional restoration of the opened habitat in the Three Rivers watershed
  • Demonstrate the effectiveness of the pneumatic Obermeyer weir for selective fish passage

Project Partners

Oregon Department of Fish and Wildlife

U.S. Fish and Wildlife Service

U.S. Forest Service

Bureau of Land Management

Natural Resources Conservation Service

Nestucca, Neskowin, and Sand Lake Watershed Council

Tillamook County

Tillamook Estuaries Partnership

Tillamook County Creamery Association

Tillamook Bay Watershed Council

Trout Unlimited

Oregon Department of Forestry

Oregon Department of Transportation

Oregon Watershed Enhancement Board

Pelican Brewing