Scottish Road Network Landslides Study: Implementation

Editors

M G Winter (Transport Research Laboratory),
F Macgregor (Consultant to Transport Scotland) and
L Shackman (Transport Scotland)

Contents

MINISTERIAL FOREWORD

EDITORS AND REPORT CONTRIBUTORS

EXECUTIVE OVERVIEW

1 INTRODUCTION

2 LANDSLIDE EVENTS
2.1 Landslides and Debris Flow
2.2 Events of August 2004
2.3 Other Events
2.4 Seasonality

3 RESPONSE TO THE 2004 EVENTS
3.1 Immediate Actions
3.2 Development of Future Management Options
3.3 Dissemination
3.4 Risk Issues in Context

4 GIS-BASED ASSESSMENT
4.1 Introduction
4.2 Background
4.3 Debris Flow Potential Assessment
4.4 GIS Methodology
4.5 Results
4.6 Conclusions

5 INTERPRETATION OF THE GIS-BASED ASSESSMENT
5.1 Description of Data
5.2 Methodology and Outcomes
5.3 Selection of Routes for Site-Specific Assessments

6 SITE-SPECIFIC ASSESSMENT METHODOLOGY
6.1 Introduction
6.2 The Inspection Process
6.3 Site-Specific Assessment results

7 SITE-SPECIFIC ASSESSMENT RESULTS
7.1 Introduction
7.2 Exposure Scores
7.3 Hazard Rankings
7.4 Re-Inspection Programme
7.5 Rock Slopes

8 MANAGEMENT OF HIGH HAZARD RANKING AREAS
8.1 Techniques for Exposure Reduction
8.2 Techniques for Hazard Reduction
8.3 Management Actions

9 LANDSLIDES, CLIMATE CHANGE, RAINFALL AND FORECASTING
9.1 Introduction
9.2 Climatic Influences on Landslides
9.3 Generalised Forecasting Methods
9.4 Case Studies
9.5 A Trigger Threshold for Scotland
9.6 Conclusions

10 CONCLUSIONS AND RECOMMENDATIONS
10.1 Summary and Conclusions
10.2 Recommendations

ACKNOWLEDGEMENTS

REFERENCES

APPENDIX A SUPPLEMENTARY INFORMATION FOR THE GIS ASSESSMENT

APPENDIX B GIS-BASED ASSESSMENT INTERPRETATION RESULTS
B.1 Initial Interpretation
B.2 Secondary Interpretation

APPENDIX C RESULTS FROM SITE-SPECIFIC ASSESSMENTS
C.1 Sample Site Inspection Reports and Score Sheets
C.2 Hazard Scores

APPENDIX D HAZARD, EXPOSURE AND HAZARD RANKINGS RESULTS
D.1 Exposure Scores
D.2 Final Hazard Scores and Hazard Rankings

APPENDIX E A BRIEF INTERNATIONAL REVIEW OF THE SIGNING OF LANDSLIDE AND OTHER HAZARDS
E.1 United Kingdom
E.2 New Zealand
E.3 Greece
E.4 Canada
E.5 Hong Kong SAR
E.6 Croatia
E.7 United States of America

APPENDIX F DRAFT TRANSPORT SCOTLAND LEAFLET: SCOTTISH ROADS AND LANDSLIDES
F.1 Precautions for Safer Journeys
F.2 Context
F.3 Transport Scotland Actions

APPENDIX G LANDSLIDES AND RAINFALL: CASE STUDIES
G.1 Australia
G.2 Hong Kong SAR
G.3 Italy
G.4 Jamaica
G.5 Nepal
G.6 Norway
G.7 Singapore
G.8 Slovenia
G.9 Switzerland
G.10 United Kingdom
G.11 United States of America
G.12 Other Regions and Countries
Annex G.1 Method Adopted in Preliminary Assessment by Evans (1997)

APPENDIX H DEVELOPMENT OF A RAINFALL TRIGGER THRESHOLD FOR DEBRIS FLOW255
H.1 Methodology and Sample Results
H.2 Discussion of Results
H.3 Conclusions
Annex H.1 System for Future Back Analysis

Further copies of this document are available, on request, in audio and large print formats and in community languages, please contact:

info@transportscotland.gsi.gov.uk or phone 0141 272 7100

The views expressed in this report are those of the Editors and Authors and do not
necessarily represent those of Transport Scotland or Scottish Ministers.


Published Date 6 Oct 2008 Type Mode of transport