Fish habitat in the Yankee Fork has been drastically altered as a result of mining activities in the Yankee Fork drainage and particularly where dredging occurred.  Dredging, which occurred intermittently between 1940 and 1952, obliterated the Yankee Fork stream channel and eliminated or substantially reduced the floodplain.  The new channel that formed was often trapped between the dredge tailings and the valley hillside, where it was unable to reestablish a natural meander pattern.  Further, flood-flows were contained between the hillside and dredge tailings resulting in increased stream energy, which mobilizes spawning gravels and wood out of the reach.  The inability for this area to naturally recover is also exacerbated by the removal of trees from the streamside.  

Timber harvest began occurring in the Yankee Fork in the mid-1800s and was conducted primarily to support mining.  “By…[1904], the hills for miles around Custer were denuded of trees, as huge quantities of wood had been used for homebuilding, mine supports, and mills.”  This timber harvest was followed, in the dredged area, by clearing to facilitate dredging.

Over the past several years, landowners, agencies, and conservation groups have partnered to implement several projects throughout the dredged reach.  Trout Unlimited is currently proposing to implement a habitat improvement project in the Bonanza City area upstream from the Preachers Cove project, which was implemented during 2014.  

Partners believe that this section of the Yankee Fork has the potential to be improved substantially through removal of dredge tailings to form a flood-plain, construction of a new channel within that flood-plain, and additions of large wood in the reaches up and downstream from that area.  

Following completion of all three phases of this project, in-stream hydraulic and habitat complexity within the main-stem Yankee Fork River will be returned to natural conditions.  It will therefore enhance fish habitat for all life-stages of migratory and resident fish, provide refugia during high flows, provide cover during high and low flows, provide winter habitat for juvenile salmonids, and provide spawning areas for all salmonids. Salmonids that will benefit from this project include spring/summer Chinook salmon, summer steelhead, bull trout, and westslope cutthroat trout.  


Stream substrates, including riffle material and spawning gravel will be generated during Phase I onsite by screening dredge tailings.

The Bonanza City project will consist of three phases that will include habitat additions, in the form of large wood, in the upstream and downstream reaches; removal of dredge tailings from the flood-plain and stream and habitat construction in the middle reach.  Phase I of this project will be completed during 2018, with Phase II and Phase III scheduled for completion during 2019 and 2020 respectively.