Lower Subbasin Overview
The Lower Subbasin drains approximately 69 square miles of the southwestern portion of the Van Duzen River Basin, including approximately 23 miles of the mainstem Van Duzen River, 54 miles of perennial tributary channels and 85 miles of intermittent tributary stream channels according to 1:1000 USGS maps Grizzly Creek is the eastern most planning watershed in the subbasin, marked by the approximate eastern extent of the coastal fog zone and distribution of redwood forests. Nearly all the land in this subbasin (97.7%) is privately owned, and the remaining 2.3% is owned by the state. Primary land uses include timber production, dairy and cattle ranching, gravel mining and residential developments. The towns of Hydesville and Carlotta (subbasin surrounds the actual town limits) are centers for residential developments located in the lower river valley. There are two county parks (Swimmers Delight and Pamplin Grove) and Grizzly Creek State Park in the Lower Subbasin designed to conserve natural resources and provide recreational opportunities to the public.
Streams of the Lower Subbasin support populations of Chinook salmon, coho salmon, steelhead, and coastal cutthroat trout. The largest tributaries in this subbasin are among the most important salmonid producing streams in the Van Duzen River Basin, including Grizzly Creek, Root Creek, Hely Creek, and Cummings Creek.
The main channel of Hely Creek has been split by a debris accumulation at a site approximately 200 yards above its mouth. Flow has been diverted to both sides of this debris accumulation, severely eroding both stream banks and increasing channel width. Live trees now grow in the center of the previously active channel and they recruit sediment and more debris. Our recommendation is restore channel form by moving some of the wood debris to open the middle of the stream, secure some of the wood to armour stream banks around the site, and remove live vegetation from active stream channel, planting the banks as needed. There are other sites like this along Hely Creek.