Douglas Creek, a basin-fed, third-order
stream, originates in Powell County on properties of mixed ownership. From its
headwaters, it flows easterly through Bureau of Land Management land, Plum Creek Timber
Company land and several ranches. Its base flow is approximately 12 cfs at its
confluence with Nevada Creek at river mile 4.4.
Douglas Creek supports a pure
population of westslope cutthroat trout in the headwaters, but supports an impaired
fishery in lower reaches. In 1994, fish population inventories at two locations
(river mile 0.2 and 8.0) of lower Douglas Creek recorded no salmonids below river mile 8.0
and no fish at the river mile 0.2. In 1997, four additional upstream fishery surveys
were undertaken (river mile 11.2, 14.3, 15.5 and 16.0) in the headwaters of Douglas Creek
located above, between and below a series of instream reservoirs. These fishery
surveys recorded a significant shift in the composition of the fishery, ranging from 100%
cutthroat trout in the upstream sample (river mile 16.0), to 98% non-game fish at the
lower station (river mile 11.2). The upstream sample, taken above the reservoir,
recorded a CPUE for westslope cutthroat trout of 5.4 fish/100 feet compared to 0.7
fish/100 feet at the downstream section, below the reservoirs.
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. Douglas Creek is ranked 36 of 83 streams surveyed.
Two large fish ladders were constructed
in the spring of 2001. In both cases, we installed rock step/pool structures with vertical
heights of over 20 feet. These two projects opened up five miles of critical spawning and
rearing habitat for westslope cutthroat trout.
|Existing culvert in upper dam used for
irrigation. As you can see, this structure
prevents all upstream migrations.
|Aerial view of newly constructed fish
ladder prior to turning in water.
Other projects in the
watershed include grazing management along Douglas Creek and two of its tributaries as
well as off-site water development. The principle landowner in this watershed has
completed conservation easements perpetually protecting over 8,000 acres. We are presently
working with the ranch on an additional easement protecting 7,000 acres.