SCOTCH, KWIKOIT and CORNING CREEKS DETAILED and RECONNAISSANCE

TERRAIN STABILITY MAPPING SALMON ARM FOREST DISTRICT

P.·oject No. 0808-98-89822

DETAILED and RECONNAISSANCE TERRAIN MAPPING with INTERPRETATIONS for TERRAIN STABILITY,

SURFACE EROSION POTENTIAL, and SEDIMENT TRANSFER POTENTIAL SALMON ARM FOREST DISTRICT, B.C.

Prepared for: FEDERATED CO-OPERATIVES LIMITED

Canoe, B.C.

Administered by: mGH COUNTRY FORESTRY CONSULTING LTD.

Salmon Arm, B.C.

Prepared by:

EBA ENGINEERING CONSULTANTS LTD. Vancouver, B.C.

Project No. 0801-98-89822

May, 1999

This project has been funded by FOREST RENEWAL BRITISH COLUMBIA

0808-98-89822 May 1999

TABLE OF CONTENTS

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1.0 INTRODUCTION .................................................. ~ .......................................................... 1 2.0 METHODS ........................................................................................................................ 2

2.1 Terrain Mapping ......................................... l. ......................................................... 2 2.2 Mapping Reliability .................................... 1. ......................................................... 3 2.3 Terrain Stability Interpretations .................. J. ......................................................... 4 2.4 Surface Erosion Potential Interpretations ... ~ .......................................................... 6 2.5 Sediment Transfer Potential Interpretation ............................................................ 7

3.0 PHYSIOGRAPHY .................................................•.......................................................... 9 3.1 Topography and Bedrock Geology ............. J .......................................................... 9 3.2 Landscape Evolution and Deposition ofSuhicial Materials ............................... 10

4.0 SURFICIAL MATERIALS AND ASSOCIATED LANDFORMS ............................... 11 4.1 Till (M) ....................................................... J •••••••••••••••••••••••••••••••••••••••••••••••••••• •••• 11 4.2 Glaciofluvial Materials (FG) ................................................................................ 12 4.3 Colluvium (C) ............................................. .! ........................................................ 13 4.4 Fluvial Materials (F) ................................... .! ........................................................ 14

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4.5 Glaciolacustrine (LG) and Lacustrine (L) Materials ........................................... 14 4.6 Organic Materials (0) .......................................................................................... 15 4.7 Weathered Bedrock (D) ............................... ' ........................................................ 15

5.0 ACTIVE GEOMORPHOLOGICAL PROCESSESi ........................................................ 15 I

5.1 Rapid Mass Movement (-R, -R") and Slow ~ass Movement (-F, -F") .............. 15 5.1.1 Debris Slides (-Rs, -R"s) and Debris Flows (-Rd, -R"d) ....................... 15 5.1.2 Rockfall (-Rb, -R"b) ............................................................................... 17 5.1.3 Slump in Bedrock (-Fm, -F"m) .............................................................. 18

5.2 Gully Erosion (-V) ....................................... ~ ....................................................... 18 5.3 Meltwater Channels (-E) ............................. j ••••••••••••••••••••••••••••••••••••••••••••••••••••••• 18 5.4 Snow Avalanches (-A) ................................. ~ ....................................................... 19 5.5 Abundant Seepage (-L) ........................................................................................ 19

6.0 TERRAIN STABILITY, SURFACE EROSION POTENTIAL AND SEDIMENT TRANSFER POTENTIAL: DISCUSSION AND MANAGEMENT IMPLICATIONS ........... 19

6.1 Terrain Stability- Discussion ...................... .L ...................................................... 19 6.2 Surface Erosion Potential- Discussion ...... ..1 ....................................................... 20 6.3 Terrain Stability and Surface Erosion Potential- Management Implications ...... 21 6.4 Management Implications for Sediment Transfer Potential Classes ................... 23

7.0 RECOMMENDATIONS ........................................ , ....................................................... 24 8.0 REFERENCES ........................................................ 1 ....................................................... 26 9.0 CLOSURE ............................................................... 1 ....................................................... 27

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0808-98-89822 May 1999

Appendix A AppendixB Appendix C Appendix D

APPENDICES

............................................................................................. Annotated Photographs

...................................................................................... Legend for Terrain Symbols

............................................................................... Air photo and TRIM sheets used

.............................................................................. Field Fonn.s (separate document)

FIGURES

Figure 1 .................................................................................. Traverse Routes and Area Boundary

Terrain and Interpretative Maps, although not bound with this document, accompany this report.

Table 1 Table 2.1

Table 2.2 Table 2.3a Table 2.3b Table 2.4 Table 2.5 Table 4

Table 5 Table 6 Table 7

TABLES

Previous Terrain Stability Mapping in Adjacent Watersheds .......................... 1 Infonnation Displayed in the Polygon on the Terrain and Interpretative Maps ........................................................................................... 3 Field-Checking Statistics .................................................................................. 4 Guidelines for the Assessment Terrain Stability (DTSM) ............................... 5 Guidelines for Assessment of Terrain Stability (RTSM) ................................. 6 Guidelines for Assessment of Surface Erosion Potential on Steep Slopes ....... 7 Guidelines for Assessing Sediment Transfer Potential .................................... 8 Management Implications for Detailed Terrain Stability Classification (DTSM) .......................................................................................................... 21 Management Implications for Terrain Stability Classification (RTSM) ........ 22 Management Implications for Surface Erosion Potential Classification ........ 22 Management Implications for Sediment Transfer Potential Classification .... 25

0808-98-89822 1 May 1999

1.0 INTRODUCTION

The objective of this project was to prepare detaile~ and reconnaissance terrain stability maps, including surface erosion and sediment transfer potential ratings, at 1 :20,000 scale, for the Scotch Creek watershed, including Kwikoit Creek and Coming (Lee) Creek (see Figure 1). This work was done for Federated Co-operatives Limited, Canoe, B.C. and

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administered by High Country Forestry Consulting t.td., Salmon Arm, B.C. Funding for this project was provided by Forest Renewal British Columbia (FRBC) under the landbased programs. The terrain stability mapping de~cribed in this report edge-matches to the detailed terrain mapping and interpretations for t~rrain stability, erosion potential, and sediment transfer potential for other watersheds in the area previously mapped by EBA Engineering Consultants Ltd. (EBA) and 1M. RYder!and Associates Terrain Analysis Inc. (JMRA).

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The 64,000 ha area of Scotch Creek includes its main tributary (K wikoit Creek) and a small watershed west of the mouth of Scotch Creek 1'(Corning Creek). The Scotch Creek area extends north to the southern edge of the Celist3j CreeklHumamilt Lake area (mapped in 1997) and west to the Salmon Arm Forest District~oundary. To the east and south, the area is bounded by some unmapped terrain and m~pped (North Shore Shuswap) along Shuswap Lake and Seymour Arm (Figure 1). '

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The project area boundary edge-matches to terJain stability mapping In adjacent watersheds to provide seamless coverage (Table 1). !

TABLEt Previous Terrain Stability Mapping in Adjacent Watersheds

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Adjacent Project Watersheds I

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EBA Engineering Consultants Ltd., ; 1997. Reconnaissance Terrain Stability Celista Creek - Mapping (TSIL D) for the Celista Creek-Humanilt Lake, Sim Creek and Pickett-Humamilt Syphon-Palmer Creek Watersheds. Report and 1:20,000 scale maps. Prepared for

Federated Co-operatives Ltd .. I

North Shore EBA Engineering Consultants Ltd., 1998. Terrain Stability Mapping for the Salmon Arm Forest District TSIL C and E (Nclrth Shore Shuswap). Report and 1:20,000

Shuswap scale maps. Prepared for Federated Co-bperatives Ltd., Salmon Arm

Terrain mapping and interpretations for terrain stability and surface erosion potential were carried out according to the provincial standards (Seftion 2). Sediment transfer potential refers to the potential for sediment delivery to streams from both surface erosion and landslides. This interpretation combines the ratfugs for "landslide induced stream sedimentation" and "potential for sediment delivery from surface erosion sources" as defined in the Mapping and Assessing Terrain Stabiliw Guidebook (Forest Practices Code, 1995).

This report augments the infonnation that is shown on the maps provided. It explains the methodology used and mapping reliability (Sectioh 2), provides an overview of the

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