SOUTH THOMPSON RIVER Inventory, Mapping, and Aquatic Habitat Index
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SOUTH THOMPSON RIVER Inventory, Mapping, and Aquatic Habitat Index Prepared By: Ecoscape Environmental Consultants Ltd. Prepared for: Fraser Basin Council on Behalf of South Thompson-Nicola Regional District, City of Kamloops, Adams Lake Indian Band, and TK’emlups te secwepemc SOUTH THOMPSON RIVER Inventory, Mapping, and Aquatic Habitat Index A Living Document – Version 1.0 Prepared For and In Partnership With: FRASER BASIN COUNCIL ON BEHALF OF: SOUTH THOMPSON-NICOLA REGIONAL DISTRICT, CITY OF KAMLOOPS, ADAMS LAKE INDIAN BAND, AND TK’EMLUPS TE SECWEPEMC Prepared By: ECOSCAPE ENVIRONMENTAL CONSULTANTS LTD. # 102 - 450 Neave Court Kelowna, BC V1V 2M2 May 2016 Ecoscape File No. 15-1588 102 – 450 Neave Ct. Kelowna BC V1V 2M2 Tel: 250.491.7337 Fax: 250.491.7772 www.ecoscapeltd.com 15-1588 i May 2016 ACKNOWLEDGEMENTS This project would not have been realized without the assistance and contribution from the following individuals and organizations: Department of Fisheries and Oceans Canada – for their support and expertise in development of the RIM methodology and Aquatic Habitat Index as it was first developed for the Lower Shuswap River project and carried forward to the South Thompson River project. Salmon spawning information was contributed by Fisheries and Oceans Canada (2015) Support for this project was provided by: Fraser Basin Council National Conservation Plan – Canada and South Thompson-Nicola Regional District Field Inventory Crew: Kyle Hawes (Ecoscape) Bob Harding (Fisheries and Oceans Canada Tracy Thomas (Fraser Basin Council) Jennifer Pooley (Adams Lake Indian Band) The following parties contributed to the development of the Aquatic Habitat Index: Kyle Hawes, Ecoscape Environmental Consultants Ltd Jason Schleppe, Ecoscape Environmental Consultants Ltd Bob Harding, Fisheries and Oceans Canada Bruce Runciman, Fisheries and Oceans Canada The principle author of this report was: Kyle Hawes, R.P.Bio. (Ecoscape) Geographical Information Systems (GIS) mapping and analysis was prepared by: Robert Wagner (Ecoscape) Rachel Plewes (Ecoscape) Recommended Citation: Hawes, K. R. Wagner, R. Plewes and J. Schleppe. 2016. South Thompson River Inventory, Mapping, and Aquatic Habitat Index. Ecoscape Environmental Consultants Ltd. Project File: 15-1588. 63pp + appendices. _____________________________________________________________ 102 – 450 Neave Ct. Kelowna, BC V1V 2M2 tel: 250.491.7337 fax: 250.491.7772 www.ecoscapeltd.com 15-1588 ii May 2016 INFORMATION DISCLAIMER The results contained in this report are based upon data collected during a single season inventory. Biological systems respond differently both in space and time. For this reason, the assumptions contained within the text are based upon field results, previously published material on the subject, and airphoto interpretation. The material in this report attempts to account for some of the variability between years and in space by using safe assumptions and a conservative approach. Data in this assessment was not analyzed statistically and no inferences about statistical significance are made if the word significant is used. Use of or reliance upon biological conclusions made in this report is the responsibility of the party using the information. Neither Ecoscape Environmental Consultants Ltd., nor the authors of this report or Fraser Basin Council is liable for accidental mistakes, omissions, or errors made in preparation of this report because best attempts were made to verify the accuracy and completeness of data collected, analyzed, and presented. This is intended as a “Living Document”. In so being, it may be continually edited and updated and may evolve and be expanded as needed, and serve a different purpose over time. 102 – 450 Neave Ct. Kelowna, BC V1V 2M2 tel: 250.491.7337 fax: 250.491.7772 www.ecoscapeltd.com 15-1588 iii May 2016 EXECUTIVE SUMMARY A comprehensive inventory was completed for the South Thompson River (STHM) in November 2015 from Little Shuswap Lake (Chase) downstream to Kamloops Lake and to subsequently complete an AHI. This Large River Inventory and Mapping approach (RIM) adapts the data collection methods and standards of Sensitive Habitat Inventory and Mapping (SHIM) (Mason and Knight, 2001) and Foreshore Inventory and Mapping. The ensuing Aquatic Habitat Index (AHI) uses many different criteria, such as biophysical, fisheries values, and anthropogenic characteristics to estimate the relative habitat value of river reaches and bank segments that were defined during the inventory. The Habitat Index classifies this information in a 5-Class system from Very High to Very Low. The South Thompson River flows from Little Shuswap Lake to Kamloops Lake, a distance of approximately 70 km. The River was broken into a total of 21 reaches. The left bank (looking downstream) was divided into 64 Segments and the right bank was broken into 90 Segments. The STHM forms a straight to mildly sinuous channel thorough glaciolacustrine sediments. This results in the predominance of benched to mildly sloping river banks that are composed primarily of silt. The hydraulic character is predominantly glide with fine-textured substrates (i.e. sand/silt) over lower reaches. There is a marked increase in channel complexity (moving upstream) and habitat quality beginning around the Campbell Creek fan (downstream of the Lafarge Bridge). Deep pools, important for cover and general living as well as holding areas for anadromous migrations, amount to about 84 ha (3%) of the river. Of this area, only about 10 ha have been identified by the Department of Fisheries and Oceans (2015) as key holding areas. In total, only about 4% of the STHM has documented salmon spawning use. Sockeye spawning in the STHM is only documented in the uppermost reach (21) just below Little Shuswap Lake, accounting for only about 0.1% of the river (by channel area). Moderate to Moderate–High Chinook spawning use areas occupy about 1.6% of the river. High and Very High Chinook spawning intensity is provided by about 1% and 0.5 of the river respectively. Over 75% of the left bank and greater than 80% of the right bank of the STHM and THOM (downstream to Kamloops Lake) have been altered by human activities. Railway (infrastructure) is persistent along the left bank of the STHM, often with associated bank armouring. Rail encroachment and disturbance along the left bank amounts to over 31 km (38%) of the STHM. Although the left bank was documented to have generally more intensive landuse activities (i.e. commercial/industrial and urbanization), the right bank of the river had a greater cumulative distance where impacts to the bank and riparian area exceeded 40% of the segment. Segments with a high level of impact (>40%) combined to over 41 km (50%) of the right bank. The combined length of highly impacted segments along the left bank totaled close to 26 km (31%) of the river from Chase to Kamloops Lake. In total, there were 14 sanctioned and informal boat launches, 277 docks, and 106 water withdrawals (intakes) recorded. Livestock access was recorded to occur on over 5.3 km of the river bank with close to 73% of being along the right bank. Bank armouring (rip rap) and 102 – 450 Neave Ct. Kelowna, BC V1V 2M2 tel: 250.491.7337 fax: 250.491.7772 www.ecoscapeltd.com 15-1588 iv May 2016 retaining walls were recorded on over 12.5 km (15%) of the left bank and 6.9 km (8%) of the right bank. Bank instability along much of the river, is largely a function of the steep silt banks that have naturally eroded over time through the glaciolacustrine silts. However, this instability is exacerbated by riparian vegetation removal and encroachment associated with agriculture and industrial, commercial, urban, and rural developments. High to extreme severity bank erosion was documented on approximately 6.0 k m (7%) of the left bank and 4.6 km (6%) of the right bank. The centerline AHI analysis resulted in about 6% of the river being ranked as Very High, 29% of the river being ranked as High, and 31% of the river ranked as Moderate. High scoring reaches included 4, 9, 10, 13, 18, and 19. Reach 21 received a Very High AHI score. Reach 4 represents the confluence with the North Thompson River. A slight increase in channel gradient within 2 km downstream of the Lafarge Bridge results in a greater prevalence of higher velocity runs and riffle-pool reaches especially prevalent around the Monte Creek confluence (Reaches 9 and 10) and then again upstream of Banana Island. Reach 21 is the uppermost reach just downstream of Little Shuswap Lake and provides high value riffle pool habitat with high documented use of both Chinook and Sockeye. In addition, the channel form, complexity, and substrates of Reach 21 have high suitability for resident fish spawning, and general living. About 42% of the left bank of the STHM is ranked Very Low to Low according to Bank AHI scores. Similarly, about 40% of the right bank is ranked between Very Low and Low. Moderate AHI segments accounted for 39% of both the left and right banks of the STHM River. Approximately 18% and 20% of the left and right bank received High to Very High AHI scores respectively. 102 – 450 Neave Ct. Kelowna, BC V1V 2M2 tel: 250.491.7337 fax: 250.491.7772 www.ecoscapeltd.com 15-1588 v May 2016 TABLE OF CONTENTS ACKNOWLEDGEMENTS ......................................................................................................................... I TABLE OF CONTENTS ...........................................................................................................................