
Nevada Spring Creek, located on the
eastern edge of the lower Nevada Creek Valley, flows from a single source artesian aquifer
with a constant summertime flow of 10 to 11 cfs. At the spring source, summer
temperatures range from 44 to 45 degrees Fahrenheit. Immediately below the source,
Nevada Spring Creek enters the alluvial plain of the lower Nevada Valley where stream
gradient quickly drops and the stream assumes a meandering course for 3.2 miles before
entering Nevada Creek at stream mile 6.2. Wasson Creek also enters Nevada
Spring Creek just below its source and adds base flows of two cfs and provides a source of
native westslope cutthroat trout to the stream.
A habitat survey conducted for Nevada
Spring Creek in 1990 reported a deteriorated condition. Beginning 0.6 miles below
the source Nevada Spring Creek stream width increases from an average of 29 feet to 57
feet in middle reaches. The survey report a wide, shallow, heavily silted stream
with poor stream bank conditions. Substrate quality was poor due to excessive
sediment, except immediately below the spring source. In lower reaches, limiting
factors included lack of spawning areas, inadequate pools, riffles and undercut
banks. An inventory rated riparian health of Nevada Spring Creek as
"unhealthy" over the entire length (Fitzgerald 1996). Temperature
studies in lower stream reaches indicate summertime stream temperatures elevated beyond
levels considered optimal for trout. 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. Nevada
Spring Creek is ranked 28 of 83 streams surveyed.
Nevada Spring Creek is one of our
highest priority streams for restoration in the Blackfoot Watershed. It has the
potential to 1) significantly improve fish recruitment in a recruitment poor reach of the
Blackfoot River; and 2) significantly decrease water temperatures in the Blackfoot River
during the summer low flow period.
In 1990, a habitat restoration project
was developed for a 0.75 mile section of the spring creek. The project included
fencing livestock from the stream, planting willows in the riparian area, and installing
woody debris to the stream. Conifer bundles were placed along the inside of stream
bends to force the deposition of sediment and speed the process of stream narrowing.
One undersized culvert was removed and replaced with a bridge in 1999 and one rock dam was
also removed.
In 2001, The Nature Conservancy
purchased the Nevada Spring Creek Ranch (1,900 acres). This acquisition paved the way for
complete channel restoration of 3.2 miles of Nevada Spring Creek. In January of 2002,
reconstruction of the appropriate pattern, profile and dimensions began on the upper 1.5
miles on the creek. Restoration will narrow the channel from an average 40 feet wide to a
bankfull width of 10 feet. A major part of this project will involve entering into a water
lease which will restore instream flows all the way to the Blackfoot River.
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Nevada Spring Creek prior to restoration.
1989 photo. |
Nevada Spring Creek seven years after
fencing riparian area and adding conifer
bundles. The stream in some areas is three
times narrower then prior to restoration. |
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