Upper Subbasin Overview

The Upper Subbasin drains approximately 143 square miles of mountainous terrain located above the confluence of the mainstem Van Duzen River with the Little Van Duzen River at river mile (RM) 48. Approximately half the land is located in each of Humboldt (73 sq. mi.) and Trinity (70 sq. mi.) counties. While the lower half of the subbsasin is primarily in private ownership, the upper half of the subbasin is mostly within the Six Rivers National Forest. Coniferous forest is the dominate type of vegetation, and timber production is the major land use. Several small rural developments and a few large private land ownerships are near the towns of Dinsmore and Mad River.

Eaton Falls located at RM 46, about two miles downstream of Dinsmore, is considered a natural barrier to upstream salmonid migrations, although there have been anecdotal reports of large salmonids (possibly steelhead) above the falls. The Van Duzen mainstem and its tributaries above Eaton Falls is populated by resident trout populations. Winter and summer run steelhead migrate to tributaries and upper reaches of the Little Van Duzen River. Passage of Chinook and coho to the Upper Subbasin is typically blocked at Salmon Falls in the Middle Subbasin, but reports of coho salmon have been made in Butte Creek and the Little Van Duzen River (Reynolds et al. 1981 and Decker and Fuller 1983).

  • Upper Van Duzen River at Eaton Falls (river mile 46).
  • View of a landslide in the upper Van Duzen River, near Eaton Falls.
  • View of a large pool on the Van Duzen River just downstream of Eaton Falls.
  • Little Van Duzen River (approximately river mile 1.7)
  • Little Van Duzen, Upper Subbasin. Excessive amounts of sediments stored in low gradient reach of Little Van Duzen. Recommendation is to continue to identify and treat sources of excessive sediment delivery to stream channels.

  • Butte Creek in Upper subbasin - arched culverts plugged with sediments. Recommendation is to investigate methods to increase culvert capacity and pass sediments stored upstream

  • Butte Creek in Upper subbasin - highly aggraded and intermittent channel due to backwater effect from lower set of arched culverts on Butte Creek.   Recommendation is to investigate methods to increase culvert capacity and pass stored sediments.