This ongoing annual project deploys field crews equipped with hand tools to assess and manually treat seasonal low-flow barriers on 30 to 40 tributaries of the Klamath and Salmon Rivers in Siskiyou and Humboldt counties, opening access to approximately 40 miles of cold-water refugia and spawning habitat each summer and fall for Chinook salmon, coho salmon, and steelhead. Treatments are temporary by design, washed out by winter floods each year, but provide critical and cost-effective passage improvements during the period when mainstem water temperatures are most likely to be stressful or lethal for salmonids.
Location: The project covers 30 to 40 tributaries of the Klamath and Salmon Rivers within the Mid-Klamath and Salmon River subbasins, primarily between the communities of Happy Camp and Orleans in Siskiyou and Humboldt. Named tributaries treated in previous years include Aikens, Boise, Black Bear, Bluff, Boise, Butler, Camp, China, Coon, Cronan Gulch, Dillon, East Fork Elk, Elliot, Elk, Fort Goff, Grider, Hopkins, Indian, Independence, Irving, Jones Gulch, Kelly’s Gulch, King, Knownothing, Little Horse, Little North Fork, Methodist, Mill, Nordheimer, Oak Flat, Plummer, Portuguese, Red Cap, Rock, Rogers, Sainte Claire, Sandy Bar, Slate, South Russian, Stanshaw, Swillup, Thompson, Ti, and Wooley Creeks, among others. The majority of sites are on Klamath National Forest lands, with access granted by the Salmon/Scott River Ranger District.
Historical Fish Presence: The Klamath River basin historically supported some of the largest runs of Chinook salmon (O. tshawytscha), coho salmon (O. kisutch), and steelhead (O. mykiss) on the Pacific Coast. Coho salmon in the Southern Oregon/Northern California Coast Evolutionarily Significant Unit are listed as threatened under the ESA. Many project sites lie within the historical territory of the Karuk Tribe, for whom salmon species are central to cultural, subsistence, and commercial life. Recent research in the basin has confirmed that lower tributary reaches function as critical summer and winter thermal refugia for juvenile salmonids when mainstem Klamath and Salmon River temperatures reach stressful or lethal levels — a condition exacerbated by drought, climate change, and legacy watershed disturbances including wildfires, road failures, and mining-related sediment loading.
Project Lead: Salmon River Restoration Council (SRRC)
Project Partners: Mid Klamath Watershed Council (MKWC) — planning, implementation, monitoring, data management, and reporting; U.S. Forest Service / Klamath National Forest — primary landowner and access grantor; National Fish and Wildlife Foundation (NFWF) — funder; Karuk Tribe — endorser and knowledge partner. The project has previously received funding from USFWS, PacifiCorp, and CDFW. This project has been supported by the Forum in 2018 (Mid Klamath Fish Passage Improvement Project), 2019 (Seiad Creek Fish Passage Improvement Project), and 2021 (Mid Klamath Creek Mouth Enhancement Project).
CFPF Funding: $45,188.30
Project Description: Since 2001, SRRC and MKWC have partnered annually to identify and manually treat seasonal passage barriers on key Klamath and Salmon River tributaries. The barriers addressed are predominantly seasonal in nature — perched alluvial creek mouths where sediment accumulation from upslope disturbances causes streams to run sub-surface or too shallow for fish navigation, debris jams, and swimmer’s dams constructed at popular recreation sites — and are considered partially or wholly anthropogenic in origin. During summer low-flow conditions, these barriers prevent both juvenile and adult salmonids from accessing cold-water tributary refugia at precisely the time when mainstem temperatures are most dangerous, and in some years, coincide with the fall Chinook spawning migration window. Treatments are implemented from May through September using hand tools and native materials, and include manual construction of step pools and fishway chutes to increase depth and reduce velocity, concentrating and deepening existing pools, clearing debris blockages, and notching swimmer’s dams. Treatments are not intended to be permanent but they provide immediate, cost-effective passage improvements during critical windows. No permits are required, as the work involves no ground disturbance beyond minor, localized sediment pulses of limited duration. Public outreach includes volunteer work days involving local youth (including Youth Environmental Summer Studies and Rios to Rivers programs), intern training, and educational signage at recreation sites. The project is explicitly endorsed by the Karuk Tribe and the U.S. Forest Service, and is identified as “On-the-Ground Restoration Action B3” in the Mid Klamath Subbasin Fisheries Resource Recovery Plan.
Expected Completion: Fall 2024
Project Effectiveness: This is a long-running annual program with a consistent record of results since 2001. Pre- and post-treatment snorkel surveys at each site document changes in salmonid presence and abundance, and before-and-after photographs are collected at every treated barrier. The project application includes an extensive photo record from prior funded seasons (2019 and 2020) showing visible improvements in flow depth, channel connectivity, and passability at numerous tributaries following manual treatment. Given the seasonal nature of the barriers, the project does not produce permanent post-construction monitoring data in the traditional sense, but the consistent return of crews to the same sites each year provides a multi-decade record of treatment effectiveness and salmonid response across this network of Klamath tributaries.