EBA Engineering Consultants Ltd.

Transcription

1 EBA Engineering Consultants Ltd. CHARCOAL CREEK DETAILED TERRAIN STABILITY MAPPING (TSIL C) SALMON ARM FOREST DISTRICT RIVERSIDE FOREST PRODllCTS LIMITED EBA Project No #255, 1715 Dickson Ave., Kelowna, B.C.!Canada V1Y 9G6 Telephone: (250) Fax: (250) \. Internet:

2 DETAILED TERRAIN STABILITY MAPPING (TSIL C) CHARCOAL CREEK SALMON ARM FOREST DISTRICT Prepared by: EBA ENGINEERING CONSULTANTS LTD. Kelowna, B.C. Submitted to: Riverside Forest Products Limited EBA Project No June, 2000 This project has been funded by FOREST RENEWAL BRITISH COLUMBIA

3 TABLE OF CONTENTS 1.0 INTRODUCTION... + PAGE METHODOLOGY... ~ Terrain Mapping Terrain Mapping Interpretations Terrain Stability Class Soil Erosion Potential Class... ~ Mapping Reliability... ~ REGIONAL PHySIOGRAPHy Topography and Bedrock Geology... L Regional Landscape Evolution and Deposition of Surficial Materials I SURFICIAL MATERIALS AND ASSOCIATED LAl1DFORMS Till (M)... L Glaciofluvial Materials (FG) Colluvium (C)... j Fluvial Materials (F) Glaciolacustrine (LG) and Lacustrine (L) Mat~rials I Weathered Bedrock (D)... ~ Organic (0) ACTIVE GEOMORPHOLOGICAL PROCESSES Rapid Mass Movement (-R, -R") and Slow Mass Movement (-F, -F') I Debris Slides (-Rs, -R"s) and Debris Flo\vs (-Rd, -R"d) Rockfall (-Rb, -R"b) Tension Cracks (-F'k) and Lateral Spread in Bedrock (-F"p) Slump in Bedrock (-F'm)... J... ~ Gully Erosion (-V) Glacial Meltwater Channels (-E)... ~ Abundant Seepage (-L) TERRAIN STABILITY CLASS AND SOIL EROSION POTENTIAL CLASS - I., DISCUSSION AND MANAGEMENT IMPLICATIONS Terrain Stability Class... J Soil Erosion Potential Class... ~ Terrain Stability and Soil Erosion Potential - Management Implications RECOMMENDATIONS ACKN'OWLEDGMENTS REFERENCES... ~ I CLOSURE... j I eoa

4 FIGURES Figure 1: Location Map, Traverse Routes and Previous Mapping Projects in Adjacent Watersheds TABLES Table 2.1 Table 2.2 Table 2.3 Table 2.4 Table 6.1 Table 6.2 TRW Sheet and Air Photograph List... 2 Projects Completed in Adjacent Watersheds... 3 Guidelines for Rating Detailed Terrain Stability Class... 4 Guidelines for Rating Soil Erosion Potential Class... 5 Management Implications of Detailed Terrain Stability Classes Management. Implications of Soil Erosion Potential Classes APPENDICES Appendix A... Annotated Photographs Appendix B... Legend Appendix C...,... Field Fonns eoa

5 I! June 27, INTRODUCTION The objective of this project was to prepare detailbd terrain stability maps for Charcoal Creek with interpretations for terrain stability dass and soil erosion potential class. The project commenced in March 1999 and wk completed in May 2000 by EBA Engineering Consultants Ltd. (EBA) for Riverside Forest Products Limited I, Armstrong Division with funding provided by Forest Renewal British Columbia (FREC). Terrain stability mapping was previously completed for Charcoal Creek as a part of the Chase Creek watershed by Dobson Engineering Ltd in The Charcoal Creek watershed, also known as the China Valley, is situated about 20 km west of Salmon Arm, BC. Part of the Thompson River system, Charcoal Creek flows west from Fly Hill, then south-west to joib Chase Creek downstream of Pillar Lake. The watershed covers an area of 9792,hectares, which includes its largest tributary, Blanc Creek. I 2.0 METHODOLOGY 2.1 Terrain Mapping The terrain mapping was carried out in 3 b~ic phases: i) review of resource information and initial air photo interpretation; (ii) fieldwork and final typing; and, (iii) data entry, map compilation, editing, report Iwriting and review. To initiate the project, the following pertinent geo-physical map~ing resources were obtained: I Colour Air Photographs, 1: 17,000 scale, 1994.; Surficial Geology, Shuswap Lake, BC, Map 1~91A, GSC, scale 1:126,720. I I Bedrock Geology of the Thompson-Shuswap-Okanagan area, BC; GSC, 1979, OF 637, 1 :250,000. I Terrain Stability Mapping of the Chase Creek watershed (Dobson Engineering Ltd., 1996). I I In addition to the above resources, a number of relevant publications were reviewed (References, Section 10) prior to air photograph i~terpretation. Terrain mapping was pre-typed by generating polygons of similar tertain attributes directly onto the air photographs (see Table 2.1 for the list of the air p~otos used). The project boundaries are edge-matched to the project boundaries ofl existing terrain stability mapping projects to provide seamless coverage of the region (see Figure 1 and Table 2.2). The regional geomorphologist (BC MoF) waived th~ Stage 1 FRBC quality assurance review that is typically required at this phase.

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