Grant Agreement No.: 226479 SafeLand Living with landslide risk in Europe: Assessment, effects of global change, and risk management strategies 7th Framework Programme Cooperation Theme 6 Environment (including climate change) Sub-Activity 6.1.3 Natural Hazards Deliverable [number] D2.2b Work Package D2.1 – Harmonisation and development of procedures for quantifying landslide hazard Deliverable/Work Package Leader: UPC Revision: 0 –Final October , 2010 Rev. Deliverable Responsible Controlled by Date 0 ICG ICG October 2010 1 2 [Deliverable number] Rev. No: x [title] Date: 20xx-xx-xx SUMMARY This report includes an overview of landslide hazard and risk practices in India. It is produced by Department of Civil Engineering and Earth Sciences, Indian Institute of Technology Roorkee, india. Note about contributors The following organisations contributed to the work described in this deliverable: Lead partner responsible for the deliverable: ICG Deliverable prepared by: Dr. Manoj K. Arora, Dr. R. Anbalagan, IIT- Roorkee Partner responsible for quality control: ICG Deliverable reviewed by: Farrokh Nadim Grant Agreement No.: 226479 Page 2 of 5 SafeLand - FP7 A Report on Overview of Landslide Hazard and Risk Practices in India by Dr. Manoj K. Arora Dr. R. Anbalagan Department of Civil Engineering and Earth Sciences Indian Institute of Technology Roorkee, Roorkee- 247 667 Overview of Landslide Hazard and Risk Practices in India Department of Civil Engg. & Earth Sciences Indian Institute of Technology Roorkee 2 Table of Contents List of Figures 6 List of Tables 8 Acknowledgements 9 Abbreviations 10 1. INTRODUCTION 14 1.1 Hazards, Risks and Disasters 14 1.2 Status of Natural Disasters in India and the World 15 1.3 Government of India Initiatives on Natural Disasters 18 1.4 Objective of the Report 20 2. LANDSLIDE HAZARDS IN INDIAN CONTEXT 21 2.1 Distribution of Landslides in Various Physiographic Divisions of India 21 2.1.1 Peninsular Region 22 2.1.2 Indo-Gangetic Alluvial Plains 23 2.1.3 Himalayan Region 23 2.2 The Need for Landslide Hazard Assessment 28 3. LANDSLIDES: DEFINITION, TERMINOLOGY AND FACTORS 29 3.1 Definition and Types 29 3.2 Danger, Hazard and Risk 31 3.3 Factors Responsible for the Occurrence of Landslides 32 3.3.1 Natural Factors 33 3.3.2 Anthropogenic factors 40 3 3.3.3 Relationship Between Factors 42 4. LANDSLIDE HAZARD AND RISK ASSESSMENT 43 4.1 Creation of Landslide Inventory 45 4.2 Selection of Mapping Scales 47 4.3 Selection of Mapping Unit 48 4.4 Identification of Causative Factors 49 4.5 Creation of Thematic Database 49 4.6 LHZ using different Methodologies 50 4.6.1 Parameter Based Zonation Techniques 52 4.6.2 Inventory Based Techniques 69 4.7 Landslide Risk Assessment 71 4.7.1 Regional Risk Assessment 74 4.8 Detailed Landslide Mapping, Investigation and Monitoring 79 4.8.1 Landslide Mapping and investigation 80 4.8.2 Landslide Monitoring 84 5. CURRENT STATUS OF LANDSLIDE STUDIES IN INDIA 93 5.1 National Disaster Management Guidelines on Landslides 94 5.1.1 Structure of the Guidelines 94 5.2 Bureau of Indian Standard (BIS) codes related to landslides 100 4 5.2.1 BIS Code on Landslide Hazard Zonation (LHZ) 101 5.2.2 BIS Code on Slope Mass Rating (SMR) 102 5.2.3 BIS Code on Retaining Wall for Hill Area 104 5.3 A Concise Account on Landslide Works by Key Institutes in India 105 5.4 Progress on Creation of Landslide Inventory Database in India 109 5.5 A Portrayal of Some Individual Landslides in India 110 5.5.1 Landslides in Peninsula Region 112 5.5.2 Landslides in the Himalaya 113 5.6 Progress in LHZ mapping at Regional Level 127 5.6.1 A Chronology of Examples on LHZ mapping in Himalaya 129 5.7 Landslide Risk Zonation in India 143 5.7.1 LRA Using Danger Pixels 146 5.7.2 LRA Using Fuzzy Concept 147 5.8 Detailed Landslide Investigation, Monitoring and Early Warning Systems 152 5.8.1 Detail Landslide Investigation 153 5.8.2 Landslide Monitoring 155 5.8.3 Landslide Early Warning Systems 164 6. CONCLUSIONS 166 BIBLIOGRAPHY 169 APPENDIX ‘A’ 188 5 List of Figures Figure 1. Physiographic divisions of India 22 Figure 2. An aerial view of Malpa landslide 26 Figure 3. A panoramic view of Varunavrat landslide, Uttarkashi 27 Figure 4. Flowchart showing causative factors of landslide 33 Figure 5. An systematic organization of LHZ techniques 52 Figure 6. A typical procedure for LHZ mapping 57 Figure 7. Ground observation as indicative of stability condition of concerned slopes 83 Figure 8. Surface monitoring 86 Figure 9. An Inclinometer 88 Figure 10. A Tiltmeter installed underground 89 Figure 11. Multiple Position Borehole Extensometers (MPBE) 91 Figure 12. A Piezometer 92 Figure 13. The Harmony landslide 121 Figure 14. Frontal face of the Kaliasur landslide 123 Figure 15. Frontal face of the Birahi Ganga landslide 125 Figure 16. Frontal face of a Kandey landslide 126 Figure 17. Frontal face of a landslide near Nell village 127 Figure 18. LHZ map prepared using InfoVal method 132 Figure 19. LHZ map prepared using modified LNRF method 133 Figure 20. LSZ map prepared from Neuro-fuzzy technique 138 Figure 21. LSZ using ANN black box approach 140 Figure 22. LSZ using ratings derived from ANN 141 Figure 23. Shift phenomenon in LHZ zones 142 Figure 24. Procedure of preparing landslide risk assessment (LRA) 144 map Figure 25. Landslide risk assessment map of Sukidang area, 145 Himalaya 6 Figure 26. Steps for landslide risk assessment (LRA) using 147 danger pixels Figure 27. Steps for landslide risk assessment (LRA) using 149 fuzzy concept Figure 28. Landslide risk assessment map using danger pixels 150 Figure 29. Landslide risk assessment map using fuzzy concept 151 Figure 30. The NTPC landslide 155 Figure 31. Mansadevi landslide and its impact 163 7 List of Tables Table 1. Types of landslides 30 Table 2. Uttarkashi earthquake induced landslides 38 Table 3. Maximum LHEF rating for causative factors for Macrozonation 55 Table 4. LHZ on the basis of Total Estimated Hazard 56 Table 5. Some of the major landslides in India 111 Table 6. Damage potential of different resources at risk 144 Table 7. Vulnerability coding of population classes to devastation caused by landslides 146 8