Upper Subbasin Overview

The Upper Subbasin drains approximately 68 square miles of the CalWater 2.2 Lake Prairie Hydrologic Area and includes the land and waterways from the confluence of Lupton Creek upstream to the headwaters of Redwood Creek. This subbasin has the highest relief and greatest proportion of natural prairies of all Redwood Creek subbasins. The predominant land use is timber production and rural developments. The Upper Subbasin has the most area of all the Redwood Creek Basin in small land ownerships. The Upper Subbasin includes the following Planning Watersheds:

Windy Creek High Prairie Creek
Noisy Creek Bradford Creek
Cloney Gulch Twin Lakes Creek
Approximately 19 miles of mainstem, and 21 miles of blue line perennial tributary streams drain the subbasin. The Upper Subbasin supports populations of Chinook salmon, steelhead, and coastal cutthroat. It is unclear if coho salmon have ever spawned or reared in the Upper Subbasin.

Upper Subbasin Summary
Square Miles 67.72
Total Acreage 43,344
Private Acres 40,640
Federal Acres 2,240
State Acres 0
Principal Communities None
Predominant Land Use Timber production
Predominant Vegetation Type Hardwoods/Douglas-fir forest
Miles of Anadromous Stream 23.0
Low Elevation (feet) 866
High Elevation (feet) 5,322
The Upper Subbasin provides important spawning grounds and year round rearing habitat for anadromous salmonids. High water temperature and a shortage of deep, complex pool habitat are factors limiting salmonid production in the mainstem Redwood Creek below Minon Creek. The lack of deep and complex pool habitat was also identified as a potential limiting factor in tributary streams.

The Upper Subbasin was severely affected by the combination of intensive land use activity and historical flood events in 1955, 1964, and 1997. The channel more than doubled in width and shade benefits of riparian vegetation and moderating air temperatures from near stream forests were lost, leading to increased water temperatures. Habitat impairments associated with channel widening and high stream temperature still adversely affect habitat suitability throughout much of the upper Redwood Creek mainstem.

While current habitat conditions differ from those of pre-management days, aspects of the upper mainstem appear to have recovered from the impacts of land management and floods. Much sediment has moved downstream, pools have re-formed and the channel substrate shows improved spawning suitability. However, excessive erosion continues to be a problem as the Upper Subbasin currently yields more suspended sediment to the mainstem of Redwood Creek than the Middle and Lower subbasins combined.

The Upper Subbasin offers good opportunities for implementing watershed improvement activities. Watershed management strategies aimed at reducing sediment inputs by reducing erosion will help address landscape issues that contribute to impairment of aquatic habitat. Stream habitat improvement projects should focus on preserving cool water flowing from the headwaters reach of Redwood Creek re-establishing riparian shade and reducing the channel width along mainstem Redwood Creek. Restoration projects such as tree planting and adding LWD and shelter complexity to stream channels may increase the rate of stream recovery. Adding shelter complexity to cool water refuge sites will provide summer steelhead with protective cover needed during their summer holding stage. In tributary watersheds, stream habitat improvement activities should focus on increasing frequency, depth and complexity of pool habitats, adding instream shelter complexity, and promoting nearstream coniferous forest growth retention.

Redwood Creek - Upper Subbasin

Redwood Creek - Upper Subbasin

Large debris accumulation near mouth of Lake Prairie Creek. This migration passage barrier formed from a debris torrent in 1997.