The Van Duzen River Basin drains approximately 430 square miles of mountainous terrain in California’s North Coast Range (Figure 1). Eighty-four percent of the basin is within Humboldt County and the remaining portion (16%) is within Trinity County. The Van Duzen River is a major tributary to the Eel River which flows into the Pacific Ocean approximately 15 miles south of Eureka, in Humboldt County. Elevations in the Van Duzen River Basin range from approximately 5,900 feet at the upper basin headwater peaks (Mount Lassic, Black Lassic, and Red Lassic) to a low elevation of 60 feet where the Van Duzen joins the Eel River near the town of Fortuna, and approximately 13 miles from the Pacific Ocean.
The Van Duzen River is one of the few remaining un-dammed rivers in California. In addition to its free flowing quality, the Van Duzen River is recognized for its extraordinary scenic, recreational, and fish and wildlife values. Anadromous salmonids found in the Van Duzen River Basin include: California Coastal (CC) Chinook Salmon - status: threatened (federal listing); Southern Oregon/Northern California (SONCC) coho salmon - status: threatened (federal and state listing); Northern California (NC) steelhead trout – status: threatened (federal listing); and coastal cutthroat trout. To help protect these resources and values, sections of the river were added to the State Wild and Scenic River system in 1972. The State Wild and Scenic Rivers Act mandates that federal, state and county agencies protect the free flowing character and extraordinary values of the designated reaches of Van Duzen River. In 1981, those river reaches also received National Wild and Scenic River designation. In addition, in 1999, the Van Duzen River was listed by the U.S. Environmental Protection Agency (USEPA) under the Total Daily Maximum Load (TMDL) program as sediment impaired and water quality limited. The TMDL listing is due to impacts of sedimentation/siltation on beneficial uses including maintenance of critical aquatic habitat which supports anadromous salmonids.
Many of the people that work, recreate, and enjoy the scenic beauty of the Van Duzen River also live in the basin or reside close by. The small towns of Hydesville, Carlotta, Bridgeville, and Dinsmore provide services for rural, mountain community residents dispersed throughout the basin. In addition many visitors are attracted to the area to enjoy the river, forests, fish and wildlife, parks, campgrounds, and public lands.
Land owners, stakeholders, and interested parties have formed watershed groups and land conservancies to maintain and /or improve the status of the basin’s esthetic values, and economic and natural resources. These include the Yager/Van Duzen Environmental Stewards (YES), Friends of the Van Duzen River, Friends of the Eel River, the Buckeye Conservancy, and the Eel River Watershed Improvement Group (ERWIG). These groups and stakeholders along with state and federal agencies are working to promote socio-economic and natural resource sustainability. Watershed improvement projects have focused on reducing erosion and sediment delivery to streams by improving road conditions and watercourse crossings, stabilizing stream banks, improving instream habitat conditions with instream enhancement structures, and facilitating anadromous fish passage. The majority of these projects have occurred on privately owned lands.
In order to be more specific and of value to planners, managers, and landowners, it is useful to subdivide the large basins into smaller subbasin units. The subbasins boundaries are determined by the commonality of many geographic attributes. Attributes that can distinguish subbasins include differences in elevation, geology, soil types, climate, vegetation, human population, and land use. The Van Duzen Basin was divided into four subbasins for this assessment: Yager, Lower, Middle, and Upper. The subbasins conform to CalWater 2.2 Planning Watershed boundaries when possible and the planning watersheds as defined by the CalWater 2.2 system.