Project Objectives:
The overall objective of the project is to improve riparian and stream conditions in Chesnimnus, Peavine, and Devils Run creeks in the Upper Joseph Creek Watershed, continuing implementation of project recommendations developed through the Upper Joseph Creek Watershed Assessment (see
www.wallowaresources.org/ujc_assessment).
Specific project objectives are:
• Improve streambank stability
• Improve habitat for fish and other wildlife
• Improve stream width to depth ratios
• Improve juvenile fish passage
• Decrease sediment input to streams
The Upper Joseph Creek subwatershed has been identified as one of the five highest priority Geographic Areas for restoration for the Joseph Creek Steelhead population (Grande Ronde Subbasin Plan, p. 16). The instream structure portion of this project would address the Key Limiting Factors of Key Habitat Quantity and Temperature. Modifying the instream structures will allow the channel to narrow downstream. A narrower channel has the potential to decrease stream temperature. The weed treatment portion of this project addresses the Key Limiting Factor of Sediment. Weeds like sulfur cinquefoil can form dense monocultures, produce lots of seed and spread rapidly. This infestation has the potential to spread to the riparian area directly adjacent to the Peavine Creek road. Sulfur cinquefoil crowds out desirable vegetation that would hold soil in high water events. The Plan also states that restoration in this subwatershed will have a large impact on Snake River Steelhead abundance and productivity (p. 17).
In addition, the instream structure modification will address Problem 7 (Table 5-1, p. 32) where population connectivity is reduced as a result of structural barriers within specific watersheds. These log weirs can block passage of juvenile steelhead during low flow in both Peavine and Chesnimnus creeks.
Project Description:
Introduction - The project is designed to improve instream habitat and riparian areas for threatened steelhead and a variety of other wildlife species within the Upper Joseph Creek Watershed. Modification of in-stream structures and weed treatment in combination with monitoring are proposed to enhance the existing condition. Components of this project have been identified through site-specific observations by fish biologists, wildlife biologists, hydrologists, as well as recommendations developed through the Upper Joseph Creek watershed assessment.
Existing Condition - Numerous passive and active restoration projects have been implemented in the Upper Joseph Creek Watershed to improve riparian vegetation, channel morphology and complexity, water quality and fisheries habitat. While many of these projects have produced their intended results, some have generated unintended consequences. An example of this includes the instream structures installed in Chesnimnus, Peavine, and Devils Run creeks in the mid-1980s. The intent was to provide scour holes for fish rearing habitat and increase the amount of large woody debris in the creek system. However, most structures now exhibit excessive bank scour on the downstream side of the structures and are barriers to juvenile fish passage. Reconfiguring these structures will allow for juvenile fish passage and stream narrowing, while increasing fish habitat complexity with the addition of whole trees. During the summer of 2005, 36 of these structures were modified in Chesnimnus Creek using BPA funding.
Forest Service Road 4660 along Peavine Creek has been closed to full-size vehicle traffic since for approximately 10 years. However, the road remains open to ATV traffic. An ATV bridge at the bottom of the Peavine Loop road makes this an enticing place to ride. In addition, the road is heavily traveled by livestock, wildlife, hunters and bicyclists. Inspection of this road in 2005 revealed a heavy infestation of sulfur cinquefoil. Given the large amount of traffic this road receives, sulfur cinquefoil should be treated to reduce the potential for its spread in Upper Joseph Creek and elsewhere.
Benefits:
Benefits from this project should include the following:
• Improved juvenile fish passage
• Improved streambank stability
• Decreased sediment input to steams
• Improved habitat for a fish and other wildlife
Improved fish passage and habitat will be realized immediately. The other benefits will be realized in 2-10 years.
Project Maintenance:
No further maintenance will be required for the former instream structures. The USFS will be responsible for the maintenance of the sulfur cinquefoil project.