Homathko River Remediation at Mile 4.0, and Effectiveness Monitoring of 3.5 Mile Restoration
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FOREST INVESTMENT ACCOUNT - LAND BASED PROGRAM - Stream Restoration Project - Homathko River Remediation at Mile 4.0, and Effectiveness Monitoring of 3.5 Mile Restoration. Summary Report: 2009/10 IS# COTSA386884 Project No. 6886008 By Warren Warttig, RPBio Senior Planning Biologist International Forest Products Ltd. Forestry & Land Use Division 1250-A Ironwood Street Campbell River, BC V9W 6H5 [email protected] March 31, 2010 This page is intentionally left blank 2 Abstract In December of 2009, workers in the Homathko River area noticed an area of substantial erosion near 4.0 mile on the Homathko Mainline and reported it to DFO and the Campbell River Salmon foundation, and finally International Forest Products Ltd. (Interfor). The concern was, that left untreated, would eventually break through into Cumsack Slough, which is a highly productive rearing area for Salmonids. The site was inspected by DFO on March 4th, and plans developed to protect Cumsack Slough. While on site, effectiveness monitoring on restoration work in 2006 and 2007 was completed. Snow and wind delayed the project start until March 26, 2010. The project entailed armouring the erosion area with large angular rock and was completed by March 30, 2010. 3 This page is intentionally left blank 4 Table of Contents: Abstract............................................................................................................................................ 3 Acknowledgements ......................................................................................................................... 7 Introduction ...................................................................................................................................... 8 Introduction ...................................................................................................................................... 9 Location ......................................................................................................................................... 10 Project............................................................................................................................................ 11 Cost Breakdown ............................................................................................................................ 12 DFO Mitigation Plans and Effectiveness Monitoring ..................................................................... 13 5 This page is intentionally left blank 6 Acknowledgements The author wishes to acknowledge the help of the Campbell River Salmon Foundation (in particular Mike Gage) and Richard Powley, Rick Senger, and Mel Sheng from DFO for their assistance (past and present). 7 This page is intentionally left blank 8 Introduction Cumsack Slough is a unique ground-water fed wetland; it is Figure 1 over 700 ha in size and a very productive salmonid rearing area (figure 1 and 2). The Slough is considered to be threatened by the lower Homathko River which is shifting river-right towards Cumsack Slough near the 3.5 to 4.0 Mile on the Homathko Mainline. This has been an ongoing problem since (at least) 1993. The earliest known report was prepared by Hay and Company (Hayco) for Scott Paper in 1993, and Mike Miles and Associates Ltd. has previously prepared Figure 2 reports for this area for Interfor in 2000, 2001, 2002 and 2003. Extensive armouring has been completed from 2000 to 2004 by Interfor with only moderate effect only 300 m of the outside bend remaining intact. In 2005 Mel Sheng (DFO) designed a deflection groin and Newbury weir to mitigate the erosion problems, and in March 2006 the deflection groin and weir were constructed (figure 1), along with some in channel excavation. Due to limited funds, only a small weir was finished in 2006, and in 2007 the weir was extended both upwards Figure 3 and outwards. This project was completed with joint funding from the Pacific Salmon Foundation and Forest Investment Account (thru Interfor). It is this project that is the subject of the effectiveness monitoring in this report. In December of 2009, workers in the Looking down stream Homathko River area noticed an area of substantial erosion near 4.0 mile on the Homathko Mainline (figures 3 and 4) and reported it to DFO and the Campbell River Salmon foundation, and finally International Forest Products Ltd. (Interfor). The concern was, that left untreated, would eventually break through into Cumsack Slough, which is a very large and highly productive rearing area for Salmonids. 9 The Homathko River is a large river with a drainage basin of Looking up stream Figure 4 5335 square kilometres. The mountains flanking the Homathko River are the highest in the Coast Mountains and include Mount Waddington west of the river (in the Waddington Range) and Mount Queen Bess east of the river, adjacent to the Homathko Ice field. Also flanking the Homathko River on the west are the Niut Range, which is in the angle of the Homathko and its main west fork (Mosley Creek) and the Whitemantle Range (which is to the south of the Waddington Range) forming the mountainous ridge dividing Bute and Knights Inlets. The Homathko begins in the northern part of the Niut Range then descends to the Chilcotin Plateau coming close to Tatla Lake and Tatlayoko Lake before piercing the Pacific Ranges en route to the sea at the head of Bute Inlet. Figure 5 Location The mouth of the Homathko River is at the head of Bute inlet about 104 km at 16° from Campbell River (figure 5). The river contains Steelhead, Coastal Cutthroat Trout, Bull Trout, Rainbow Trout, Dolly Varden Char, Chinook Salmon, Chum Salmon, Coho Salmon, Pink Salmon, Longnose Sucker, Longnose Dace, Redside Shiner, Starry Flounder, River Lamprey, Eulachon, Three-Spine Stickleback, and Sculpin (FISS Data Base). It is a glacial fed system, so preferred instream window is March-April to coincide with traditional low flow periods. The Homathko River is in Region 2 (code ACT) within DFO District 5, sub-district 13N, South Coast Division. The watershed code for the Homathko River is 900-406900, and watershed identifier is 00000HOMA. The Homathko River Valley has had an extensive logging history which continues today. It is a Figure 6 prizes recreational fishing area. The Homathko River areas and tributaries of the Homathko River have recently been of interest for independent power producers. The erosion point of concern is located near 4 mile on the Homathko mainline (figure 61) approximately 600m upstream of the 2006 restoration works (figure 1). 1 The figure 6 picture was taken prior to the deflection groin being constructed 10 Project The site was inspected on March 4, 2010 by DFO (Richard Powley), a Homathco First Nations Fisheries advisor (Don Sinclair), and Mike Gage of the Campbell River Salmon Foundation. A helicopter reconnaissance of the area was completed to look for accessible rock. A contractor (Bjornson Holdings Limited) had equipment in Scar Creek (approximately 30 km form the proposed Homathko work site), so it was planned to take advantage of this efficiency to get the project completed. During the March 4 trip, Richard Powley took measurements of the proposed work site and developed a mediation plan for the site. Mr. Powley also completed an effectiveness monitoring inspection of the previous restoration work that was completed in 2006 and 2007. Snow and wind delayed the project start until March 26, 2010. The Campbell River Salmon Foundation covered the expense of flying the Bjornson Crew into Scar Creek to initiate the project which entailed armouring the erosion area with large angular rock and was completed by March 30, 2010. Severe windstorms caused significant access problems the night of March 26 and again on March 27 and required clearing with heavy equipment. The rock source originally identified during the reconnaissance turned out to include too much small rock so an alternate source 6km away was utilized. The windthrow and long haul distances added significant costs to the project. Approximately 140 loads of large angular rock was transported to the erosion site constituting about 2,400 m³ of rock. The rock was placed initially by the excavator and then top filled with the dump truck. Armouring length was approximately 35m. 11 Cost Breakdown Sum of Invoice $ M/E Consultant Project Invoice # Total Mar VIH SC 6886008-09 125131 1,718.75 Bjornson SC 6886008-09 IFP10-01 17,455.00 Grand Total 19,173.75 Original budget = $10,860 12 DFO Mitigation Plans and Effectiveness Monitoring 13 Homathko Main Rip Rap Repairs - 2010 A site reconnaissance was conducted on March 4th, 2010 to evaluate requirements for repairing minor erosion at the upstream end of rip rap bank protection along the right bank of the Homathko river, approximately 10 km. (river distance) upstream of the mouth. The following photographs illustrate the erosion site: At this point, it would probably be sufficient to simply fill the eroded void with rock. It might also be useful to construct a small groyne upstream of the tree pictured above. But, it should be pointed out that these are site-specific measures that will only buy some time – erosion at the upstream extend of the rip rap will be an on-going problem unless it is extended almost 600 m upstream to the crossing at the top of the meander loop. Note that such measures don’t necessarily have to consist of continuous rip rap – a series of groynes could also do the job. Nevertheless, either option would likely cost many hundreds of thousands of dollars. An alternative