
Cottonwood Creek South is a 2nd order
tributary to Douglas Creek entering at stream mile 1.2 in the Nevada Creek Watershed.
Cottonwood Creek begins on Bureau of Land Management land and checkerboard ownership
before entering private ranchland in the middle reaches. Stream gradient ranges from 173
feet/mile in the headwaters to 63feet/mile near the mouth.
In 2000, we established two monitoring
reaches on Cottonwood Creek; one at stream mile 10.1 and the second at stream mile 2.4. We
found a healthy riparian area at the upper survey site, which included an overstory
dominated by Douglas fir, rocky mountain maple, adler, and a diverse herbaceous flora
community. Woody debris was abundant, providing suitable fish habitat. The catch per unit
effort (CPUE) of westslope cutthroat trout in this section was 14.9/100 feet. In contrast,
the riparian area at the lower survey section lacks sustainable flows, and complexity. The
plant community consists of a sparse willow overstory with sedges, bulrush and timothy.
Problems in the lower survey section relate to dewatering, areas of livestock-related bank
degradation, and stream channelization. Zero salmonids were documented in this stream
section.
In order to prioritize restoration
resources, we developed a fisheries-based restoration priority scorecard, based on
biological, social and financial considerations, for 83 impaired tributaries of the
Blackfoot River. Cottonwood Creek South ranked 62 of 83 streams surveyed.
In 2000, a stream
restoration/demonstration project was implemented in the lower monitoring reach in an
attempt to get landowner support for riparian "Best Management Practices". This
project involved removal of an instream feed lot, development of off-site water, grazing
management, instream restoration of 0.4 miles of stream, riparian shrub plantings and
installation of fish friendly irrigation strutures.
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This photo shows the newly constructed
E4 stream type flowing away from
the feedlot. |
An old non-fish friendly irrigation diversion
was relaced with this wooden step
pool diversion. |
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