BPA Project Number:  1992-010-00
Fort Hall Reservation Stream Restoration
Fort Hall Reservation Stream Restoration
March 1, 2006 to February 28, 2007

This Statement of Work addresses the objectives and tasks of the twelfth year of Project Number 92-10, Fort Hall Reservation Stream Restoration.
The Fort Hall Indian Reservation is located in southeastern Idaho, near Pocatello, and covers roughly 544,000 acres.  Reservation surface-water resources are two large, mountainous watersheds drained by the Blackfoot and Portneuf rivers which eventually flow through the Snake River plain and enter its channel at river miles 750 and 726.  Ferry Butte, at the confluence of the Blackfoot and Snake, is the northern boundary of an undeveloped 29,000 acre prairie draining numerous springs known as the Fort Hall Bottoms.  These spring streams flow southwesterly into the lower channel of the Portneuf River, where 27,000 acres of the Bottoms have been flooded by American Falls Reservoir.  The primary goal of the project is to restore fluvial salmonid habitat that has been degraded by past anthropogenic uses, primarily agriculture, irrigation, livestock grazing, and impounded and regulated river flows.

In March 1992, the Resident Fisheries Program, by cost-sharing Bonneville Power Administration and Bureau of Indian Affairs projects, began a comprehensive program combining instream structures, riparian fencing, and riparian planting-designed to narrow and deepen stream channels, clear spawning gravels, raise water tables, stabilize banks, aggrade silt, provide cover, and reduce summer water temperatures.
In other studies instream structures have increased pools, usable spawning gravel, and undercut banks in an Oregon stream (House and Boehne 1986) and salmonid biomass in two Arizona streams (Rinne 1981).  Numerous examples with beneficial results have been shown using structures in Danish watercourses to restore meanders, banks, riffles, spawning gravels, deep pools, water quality, and fish passage (Madsen 1995).  Stream bank revegetation combined with fencing to exclude livestock has had widespread success in improving riparian vegetation, bank stability, water quality, stream morphology (Madsen 1995; Clary and Webster 1989; Duff 1977) and avifaunal diversity (Dobkin 1998); and although more difficult to prove, well designed studies have shown an associated increase in trout biomass (Madsen 1995; Platts 1981; Platts and Rinne 1985).  Well designed instream structures are expensive and must be considered as part of an overall plan which considers factors which initially produced poor habitat  (Cederholm et al. 1997).

Results from the first nine years of the Fort Hall study show that habitat enhancements in 1.9 km of Clear Creek initially increased wild trout populations 15 times and biomass 10 times over pre-treatment levels.  Density and biomass of fishes have since dropped to near pre-treatment levels.  Within two years a bison exclosure fence around 2.5 km of Clear Creek in the upper pasture reduced bare banks from a 30% frequency to less than 5%, along with an associated re-growth of upper-bank willows, dogwoods, and birch.  Bank stabilization and revegetation work on Spring Creek series 200 and 300, since 1993, has reduced eroding, un-vegetated banks from 15% frequency down to 9% along 9 km of stream.

Activities in 2006 will follow those of previous years, except where experience has enabled streamlining of work and reduction of costs to achieve optimum results   An overall "gentle," or labor intensive yet low-tech, approach to stream restoration has proven far more effective than more expensive, high-tech, heavy equipment alternatives from both biological and political aspects.   Therefore, further implementation will continue on East Fork of Diggie Creek  in the form of habitat structures, planting and sloping, and fencing of stream banks.  In addtion, tracking adult trout movement on and off reservation through telemetry will continue thoughout 2004 and 2005.
  
Efforts to optimize management of land and water use, especially in relation to irrigation and ranching will continue to be a priority in this project. In 2005, exclosure fencing will be erected to protect sensitive springs and riparian areas.  In addition to fencing, suitable areas of bare bank will be sloped and planted with willows.  Areas of stream that have been fenced during the past ten years have shown marked improvements in bank stability and density of riparian plant species.   Jack and Rail exclosure fencing has degraded over time, requiring complete replacement in some areas and frequent repair in others.  Over thirty-five structures/sites on Spring Creek, Big Jimmy Creek and Diggie Creek have been restored using the aforementioned low cost, low tech restoration techniques (Taki and Arthaud 1993; Arthaud and Taki 1994; Arthaud et al. 1995, Arthaud et al. 1996; Moser and Colter 1997, Moser 1998; Moser 1999; Moser 2000).