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Project Information Objectives The objectives of this project were to restore holding and rearing habitats for rainbow trout and re-establish channel stability and pool-riffle sequences in Rebman Creek. FRBC Region / MELP Region/MOF Region Cariboo-Chilcotin / Cariboo / Cariboo Author Dave McEwan Proponent Weldwood of Canada Ltd. Quesnel Division Watershed / Stream Willow River / Rebman Creek Location The Rebman Creek work sites are reached by heading from Quesnel to Barkerville on Highway 26 for approximately 50 km. Turn right at the West Fraser 2400 logging road and continue until 28.5 km and turn left on the 24P road. The 24P road turns into the 900A road at the Rebman Creek bridge crossing. The access to the Reach 2 and Reach 4 rehabilitation sites are approximately 3 and 6 km along the 900 A road respectively. Deactivated access roads lead down to the sites. Introduction The upper Willow River Watershed is approximately 55 km Northeast of Quesnel. Rebman Creek enters the Willow River at the top of Reach 2. The tributary lies near the northern edge of the Quesnel Highland physiographic region and has a total watershed area of 21 km2. Rainbow trout are the dominant species in Rebman Creek and are the target of restoration works. Assessments and Prescriptions The Willow River watershed was selected by Ministry of Environment, Lands and Parks, Ministry of Forests, and Weldwood of Canada Ltd. for restoration of fish habitat damaged by logging. A Level 1 Fish Habitat Assessment (FHAP) of selected reaches in the Willow River watershed was conducted in 1997 (Ferguson and Bocking 1998). Rebman Creek was identified as a heavily impacted system and a high priority for stream restoration. The lower 7 km of the stream has been logged to the streambank and has caused bank erosion, aggradation, formation of mid-channel bars, infilling of pools and loss of cover including LWD. Level 2 Fish Habitat Restoration Prescriptions were completed by LGL Limited and Northwest Hydraulic Consultants Ltd. in 1999 (Gaboury et al. 1999). Past Rehabilitation Work Riffles were constructed in Reach 4 in 1998. Three hundred metres of new habitat were created through 83 m of construction (Randall 1998). Rehabilitation Work Rehabilitation work for 1999 occurred in Reaches 2 and 4 of Rebman Creek and was undertaken by Erosion Control Inc. and LGL Limited. The Level 1 FHAP for Reach 2 and Reach 4 rated the percentage of pools and pool frequency as poor (Ferguson and Bocking 1998). The number of functional pieces of LWD in these reaches for creating pools and providing cover was also considered inadequate in the Level 1 report. The re-establishment of a pool and riffle profile will improve residual pool depths, increase hydraulic diversity, and improve the stability of spawning gravel. It will also reduce bank erosion and lead to a narrower, more stable channel over time. The installation of LWD into these streams will benefit the rearing habitat of juvenile and adult rainbow trout that require cover for summer rearing and lower velocity areas during freshets. Work was completed at a total of 19 sites over a linear distance of nearly 1 kilometer. For each work site a LWD structure and a riffle were constructed. Pools were excavated upstream of the riffle at the location of the LWD structure. The LWD structures were built to provide cover and scour at the excavated pools. The following two basic designs for the LWD structures were used with a few site specific modifications: 1) A triangular lateral log jam with two 6-8 m logs with rootwads and an additional rootwad piece; and 2) A lateral log jam with five 6-8 m logs with rootwads. The LWD structures were ballasted with boulders brought in to the site. The structures were also anchored to the bank by embedding the top 3-4 m of the logs and attaching rock ballast to the logs in the bank. A riffle base was constructed by having crews move material by hand. An excavator would then move larger boulders from the pool excavations to the riffle surface. The excavator was used to strategically place large boulders on the crest and face of the riffle to provide stability. A pool was also excavated downstream of the riffle. A schematic construction drawing of the basic riffle design used in Rebman Creek can be found in Chapter 12, figure 12-12 of WRP Technical Circular No. 9 (Newbury et al. 1997). A total of fourteen sites over 810m of Reach 2 were completed. The Level 2 prescriptions proposed that the restoration of this section of Reach 2 would provide the greatest benefits to the target species, rainbow trout. Five sites were completed in Reach 4 over 170 m. Three of the riffle constructions in Reach 4 involved adding larger material to riffles that were constructed in 1998. Outputs Channel reconstruction and installation of restoration works were undertaken on nearly 1 km of stream. Production Estimates WRP Technical Circular No. 9 indicates that an approximate 2-fold increase in resident rainbow trout numbers can be expected as a result of the instream works (Koning and Keeley 1997). Proposed Work Construction of riffle-pool sequences in Reach 2 downstream to chainage 495 m should be undertaken in 2000. The next priorities would be to re-construct Reach 3 from 500 to 570 m, Reach 4 from 0 to 50 m, and Reach 3 from 15 to 355 m. For Further Information, Contact: Reg LeBlanc Marc Gaboury 2.0 Literature Cited Ferguson, J. and R. Bocking. 1998. Willow River Level 1 Fish Habitat Assessment and Rehabilitation Opportunities. Prepared for Weldwood of Canada Ltd., Quesnel, B.C. Prepared by LGL Limited, Sidney, B.C. Koning, C.W. and E.R. Keeley. 1997. Salmonid Biostandards for Estimating Production Benefits of Fish Habitat Rehabilitation Techniques. in Slaney, P.A. and D. Zaldokas [eds.] Fish Habitat Rehabilitation Procedures. British Columbia Ministry of Environment, Lands and Parks, and British Columbia Ministry of Forests, Watershed Restoration Program, Technical Circular No. 9. Newbury, R., M. Gaboury, and D. Bates. 1997. Restoring Habitats in Channelized or Uniform Streams Using Riffle and Pool Sequences. in Slaney, P.A. and D. Zaldokas [eds.] Fish Habitat Rehabilitation Procedures. British Columbia Ministry of Environment, Lands and Parks, and British Columbia Ministry of Forests, Watershed Restoration Program, Technical Circular No. 9. Randall, R. 1998. Rebman Creek Instream 1998. Submitted to Weldwood of Canada Ltd., Quesnel, B.C. Prepared by Randall and Associates, Quesnel, B.C. Gaboury M., R. Bocking and K. Rood. 1999. Willow River Watershed Restoration Program Fish Habitat Prescriptions for Rebman Creek. Submitted to Weldwood of Canada Ltd., Quesnel B.C. Prepared by LGL Limited, Sidney, B.C. and Northwest Hydraulic Consultants Ltd., North Vancouver, B.C. Cost Breakdown
Figure 1: Pool complexing with LWD on Rebman Creek, Cariboo Region.
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