National Slope Safety System for Malaysia

Title Author(s) Citation Issued Date URL Rights A framework of a national slope safety system for Malaysia Jaapar, Abd Rasid Bin. Jaapar, A. R. B.. (2006). A framework of a national slope safety system for Malaysia. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b3738460 2006 http://hdl.handle.net/10722/50173 The author retains all proprietary rights, (such as patent rights) and the right to use in future works. A FRAMEWORK OF A NATIONAL SLOPE SAFETY SYSTEM FOR MALAYSIA By ABD RASID BIN JAAPAR BSc (Hons) (Geol) (Universiti Kebangsaan Malaysia) This dissertation is submitted in partial fulfillment of the requirements for the Degree of Master of Science in Applied Geosciences of the University of Hong Kong October 2006 Slope Safety System for Malaysia DECLARATION I declare that this dissertation represents my own work, except where due acknowledgement is made, and that it has not been previously included in a thesis, dissertation or report submitted to this University or to any other institution for a degree, diploma or other qualification. Signed: …………………………………………… Name: ……………………………………………. Date: ………………………………………………. ii Slope Safety System for Malaysia ACKNOWLEDGEMENT I should acknowledge three persons who involved in making my dream to pursue my postgraduate study possible. First, the late Mr Taufik Ali, the founder of Taufik Ali Memorial Scholarship that granted me with full scholarship. Second, my employer and my mentor in geotechnical business, Mr. Kor Beng of Soils & Foundations Sdn Bhd. His generousity and support are irreplaceable. Third, my supervisor and the Director of MSc (Applied Geosciences), Professor Andrew W. Malone. His teaching greatly influenced and improved my way of thinking. My sincere gratitude goes to all my teachers, the academics and non-academics staffs of Department of Earth Sciences, the University of Hong Kong who had assisted me in one way another. Also, to my classmates who were very supportive and friendly to me and friends at the Malaysian General Consulate office who are very kind and helpful. There are friends in Malaysia who also assisted me directly or indirectly especially Dr. Tajul Anuar Jamaludin who provided me with most of the landslide images and Dr. Asan Ali Gholam Hasan who provided me with some of research materials. Support and encouragement from staffs of Soils & Foundations group of companies are highly appreciated. The following libraries are acknowledged for allowing me to use their facilities: • Perpustakaan Tun Sri Lanang, the library of the Universiti Kebangsaan Malaysia • The library of Public Works Department • The library of Minerals and Geoscience Department • The library of Geological Society of Malaysia, and • The library of the Institution of Engineers Malaysia Utmost appreciation also goes to my brothers, sisters and relatives who are very supportive. Last but not least, my family; my dear wife, Inah – a teacher, mother, friend, advisor and my strength, and without a doubt the most astonishingly talented woman I have ever known. My girls; Wani, Dina, Izza and my boy; Icad – they are the fantastic four and wonderful kids, whose understanding and whose sacrifices made it possible for me to finish my study. This dissertation was written with strong memory of my late mother, Allahyarhamah Hajjah Rahmah binti Haji Salleh who died peacefully on 28 November 2005, Sunday at 11.30am after three months I been a student again in the University of Hong Kong. Her advice and courage will remains inside forever. iii Slope Safety System for Malaysia ABSTRACT The objectives of the study are to give an account of significant landslide events in Malaysia between 1990 and 2004, to document the existing measures on slope safety management being employed, to evaluate the press responses as well as those from the government after the disastrous landslide events and to consider a National Slope Safety System for Malaysia. The historical archives of landslide events are very important to determine the pattern, trend, consequences and other relationships in order to understand the landslides and ways to prevent or mitigate their effect. It is also important to understand the development of steps or actions taken by government toward reducing the risk of landslide hazards. Based on risk management thinking, a National Slope Safety System is outlined. The study presented in this dissertation is very brief with many crude data and assumptions. Some recommendations are made in order to have better results out of similar studies made in the future. iv Slope Safety System for Malaysia TABLE OF CONTENTS Page Title Page i Declaration ii Acknowledgement iii Abstract iv Table of Contents v List of Tables vii List of Figures vii List of Plates viii Appendices ix Chapter 1 1.1 1.2 1.3 1.4 1.5 2.4 2.5 2.6 1 Background and Significance of Study Objectives Outline of Study Limitations of Study Arrangement of Dissertation Chapter 2 2.1 2.2 2.3 Introduction 1 1 2 2 3 Landslide Hazards in Malaysia 4 General Overview 4 Physiography and Geology 5 Climate and Rainfall 6 2.3.1 Rainfall-Landslide Relationship 8 Major Landslide Events (1990-2004) 9 2.4.1 The Collapse of Highland Towers (11 December 1993) 10 2.4.2 Genting Sempah Debris Flow (30 June 1995) 13 2.4.3 Gunung Tempurung Slope Failure (6 January 1996) 16 2.4.4 Pos Dipang Debris Flow (30 August 1996) 19 2.4.5 Paya Terubong Rockslide (28 November 1998) 21 2.4.6 Sandakan Landslide (7 February 1999) 23 2.4.7 Bukit Antarabangsa Landslide (15 May 1999) 24 2.4.8 Ruan Changkul Landslide (28 January 2002) 27 2.4.9 Taman Hillview Landslide (20 November 2002) 29 2.4.10 Bukit Lanjan Rockslide (26 November 2003) 32 Landslide Fatality Data and Analysis 34 Existing Measures on Slope Management 36 2.6.1 Public Works Department (Jabatan Kerja Raya - JKR) 36 2.6.2 Department of Minerals and Geoscience (Jabatan Mineral dan Geosains - JMG) v Slope Safety System for Malaysia 2.6.3 2.6.4 2.6.5 2.6.6 Chapter 3 3.1 3.2 3.3 3.4 A National Slope Safety System General Overview Baseline Record Loss Reduction Goal Loss Reduction Plan Budget for a National Slope Safety System Implementation of a National Slope Safety System Chapter 5 5.1 Response to Landslide Events 40 General Overview 40 Press Response 40 3.2.1 Objective of Study 42 3.2.2 Method of Study 42 3.2.3 Results of Study 48 3.2.4 Press Coverage Analysis 48 Response from the Government 52 3.3.1 Legal Frameworks of Actions and Improvements of Building Controls, Planning and Environmental Requirements 53 3.3.1.1 Planning Stage 53 3.3.1.2 Design and Development Stage 54 3.3.2 Formation of National Security Council 55 3.3.3 Formation of Slope Engineering Branch 55 3.3.4 Initiatives by State Governments, Other Government Agencies and Local Universities 56 Response from Non-Governmental Organisations 57 3.4.1 Institution of Engineers Malaysia (IEM) 57 3.4.2 Environmental Non-Governmental Organisations 58 Chapter 4 4.1 4.2 4.3 4.4 4.5 4.6 2.5.2.1 National Geohazards Study 38 2.5.2.2 Land Use Suitability for Development Review 38 Local Government Department (Jabatan Kerajaan Tempatan - JKT) 38 Department of Environment (Jabatan Alam Sekitar - JAS) 38 Town and Country Planning Department (Jabatan Perancang Bandar dan Desa JPBD) 39 Private Tolled Expressway Operator 39 Conclusion 59 59 60 60 60 62 63 64 Recommendations for Further Study 64 References 65 Appendices vi Slope Safety System for Malaysia TABLES, FIGURES AND PLATES List of Tables Chapter 2 Table 2.1: Some recorded landslides between 1990 and 2004 (after Chan, 1998; Utusan Malaysia, 12/10/2004; NST, 28/11/2003 and The Star, 7/1/1996) Chapter 3 Table 3.1: Summary of main comments and contents of press coverage Chapter 4 Table 4.1: Table 4.2: The Components of Slope Safety System (after Malone, 1997) Route map of setting-up of slope safety system (modified after Malone, 1999b) List of Figures Chapter 1 Figure 1.1: Map of Malaysia Chapter 2 Figure 2.1: Figure 2.2: Figure 2.3: Figure 2.4 Figure 2.5: Figure 2.6: Figure 2.7: Figure 2.8: Figure 2.9: Figure 2.10: Figure 2.11: Figure 2.12: Figure 2.13: Annual rainfall distribution in Malaysia for the year 2000 (after Malaysian Meteorological Department). Relationship between local newspaper reports on landslides in the granitic bedrock areas of Peninsular Malaysia (1981-1998) and years, months and locations as an attempt to relate with raining seasons (after Raj, 2000) Map of Malaysia showing location of major landslide events between 1990 and 2004 Original cross-section through Block 1 of Highland Towers condominium (after MPAJ, 1994) Cross section showing sequence of retrogressive landslides (after MPAJ, 1994) Location plan of Genting Sempah debris flow (after Chow et al, 1996) Plan view of the Genting Sempah debris flow (after Chow et al, 1996) Location plan of Gunung Tempurung slope failure (after Geological Survey Department, 1996) Cross-section of the slope failure at Gunung Tempurung (after Geological Survey Department, 1996) Field sketch of Pos Dipang debris flow (courtesy of Dr. Tajul Anuar Jamaludin) Landslides surrounding Ampang, Ulu Klang area. Landslide 1 at Taman Hillview, Landslide 2 at Highland Towers condominium, Landslide 3 at Athenaeum at the Peak condominium and Landslide 4 at the Wangsa Heights condominium (after Komoo, 2004) Typical cross-section of the Bukit Antarabangsa landslide (after Kumpulan Ikram Sdn Bhd, 1999) The cross section (top) and plan view (bottom) of the Ruan Changkul landslide (after Hashim &Among, 2003) vii Slope Safety System for Malaysia Figure 2.14: Figure 2.15: Figure 2.16: Figure 2.17: Figure 2.18: Figure 2.19: Figure 2.20: Figure 2.21: Engineering geological plan of Taman Hillview slope failure showed common features (top) and distribution of inhomogenous materials after the failure (bottom) (after Komoo & Lim, 2003) The oblique view of Taman Hillview landslide (after Komoo & Lim, 2003) Location of Bukit Lanjan rockslide (after Jamaludin, 2005) GDP annual growth rates versus landslides fatalities Urban population growth versus landslides fatalities Total population growth versus landslides fatalities Apportionment of landslides events between private and public land Apportionment of landslide events between types of facilities affected Chapter 3 Figure 3.1: Figure 3.2: Figure 3.3: Figure 3.4: Figure 3.5: Figure 3.6: Figure 3.7: Figure 3.8: Figure 3.9: Figure 3.10: Figure 3.11: Figure 3.12: Chart of score value matrix for individual article/column in the newspaper. Note: i) the editorial column is directly designated with score value of 25 regardless of size and location ii) ‘headline’ denotes the main article on the page. Press coverage score value versus days for the collapse of Highland Towers Press coverage score value versus days for Genting Sempah debris flow Press coverage score value versus days for Gunung Tempurung slope failure Press coverage score value versus days for Pos Dipang debris flow Press coverage score value versus days for Paya Terubong rockslide Press coverage score value versus days for Bukit Antarabangsa landslide Press coverage score value versus days for Ruan Changkul landslide Press coverage score value versus days for Taman Hillview landslide Press coverage score value versus days for Bukit Lanjan rockslide Days of press coverage versus landslide events. The numbers on top of bars represent death tolls Total press coverage score values versus fatalities. The assigned numbers in the box represent landslide event. List of Plates Chapter 2 Plate 2.1: Plate 2.2: Plate 2.3: Plate 2.4: Plate 2.5: Plate 2.6: Plate 2.7: Plate 2.8: Plate 2.9: Plate 2.10: Plate 2.11: Plate 2.12: The collapse of Block 1 of Highland Towers condominium (after MPAJ, 1994) The aftermath of the collapse of Block 1 of Highland Towers Condominium (MPAJ, 1994) View of Highland Towers area on the first night after the collapse (MPAJ, 1994) Views of Highland Towers months after the collapse (New Straits Times, 1993) The aftermath of the Genting Sempah debris flow (Sunday Star, 2/7/1995) Schematic diagram of the Genting Sempah debris flow (New Straits Times, 1/7/1995) Gunung Tempurung slope failure, North South Expressway (after Jamaludin, 2005) Closer view of Gunung Tempurung slope failure, North South Expressway (after Jamaludin, 2005) The aftermath of Pos Dipang debris flow (courtesy of Dr Tajul Anuar Jamaludin) The debris flow path at Pos Dipang (courtesy of Dr Tajul Anuar Jamaludin) Paya Terubong rockslide (Jamaludin, 2005) Closer view of Paya Terubong rockslide. Note the damaged cars (Jamaludin, 2005) viii Slope Safety System for Malaysia Plate 2.13: Plate 2.14: Plate 2.15: Plate 2.16: Plate 2.17: Plate 2.18: Plate 2.19: Plate 2.20: Plate 2.21: The aftermath of Sandakan landslide (The Borneo Post, 1999) The search and rescue after the landslide in Sandakan (The Borneo Post, 1999) The first Bukit Antarabangsa landslide near Athenaeum at the Peak Condominium (courtesy of Dr Tajul Anuar Jamaludin) The second Bukit Antarabangsa landslide near Wangsa Height Condominium (courtesy of Dr Tajul Anuar Jamaludin) Ruan Changkul Landslide, Sarawak (after Hashim & Among, 2003) Closer view of Ruan Changkul Landslide, Sarawak (after Hashim & Among, 2003) The aftermath of Taman Hillview landslide (courtesy of Dr Tajul Anuar Jamaludin) Aerial view of Bukit Lanjan rockslide (after Jamaludin, 2005) Bukit Lanjan rockslide (after Jamaludin, 2005) Chapter 3 Plate 3.1: Plate 3.2: Plate 3.3: Plate 3.4: Plate 3.5: Plate 3.6: Plate 3.7: Plate 3.8: Plate 3.9: Plate 3.10: The New Straits Times archives in form of microfilms The Star archives in form of microfiches Equipment (monitor) used for viewing microfilms Equipment (monitor) used for viewing microfiches Example of the full size headline article in the front page of The Star (not actual scale) Example of the headline article in the front page of the New Straits Times (not actual scale) Example of the full size headline article in the inside page of The Star (not actual scale) Example of the non-headline article in the inside page of the New Straits Times (not actual scale) Example of various sizes of article in the inside page of The Star (not actual scale) Example of the headline and other size articles in the inside page of the New Straits Times (not actual scale) APPENDICES Appendix A – The World Bank and United Nations Statistics Appendix B – Report by Minister of Works at UNESCAP Meeting Appendix C – Vulnerability and Risks Management of Landslide Hazards ix Slope Safety System for Malaysia CHAPTER 1 1.1 INTRODUCTION Background and Significance of Study Malaysia located in Southeast Asia (Figure 1.1) covers the southern and central part of a peninsular that extends south from Thailand into South China Sea, known as West Malaysia or Peninsular Malaysia, while also covering the northern one-third of the neighbouring island of Borneo, includes Sabah and Sarawak known as East Malaysia. Its location gives it a tropical climate – hot and humid all year round – with annual monsoons from the southwest from April to October and from the northeast from October to February. Intense rainstorms are common. Malaysia experienced rapid development during the last two decades. Many new townships, industrial areas and housing developments have sprung up in most part of the country. Infrastructure projects such as highways, expressways, light rail transit, etc also took place in line with such development. Development on hillsides is relatively uncontrolled. Many landslide events involved fatalities in the last two decades. Therefore, it is timely for a study on the approach to develop a National Slope Safety System in Malaysia. Figure 1.1: Map of Malaysia 1.2 Objectives The objectives of the study are: i) To give an account of the significant known landslide events in Malaysia between 1990 and 2004 ii) To document the known existing measures on slope safety management being employed in Malaysia iii) To evaluate the press responses as well as government actions after the significant landslide events in Malaysia iv) To recommend an approach to design a National Slope Safety System for Malaysia 1 Slope Safety System for Malaysia 1.3 Outline of Study The study is concentrated on compiling information on past significant events in Malaysia that occurred between 1990 and 2004 based on published literature, reports, newspapers or personal discussion. The information recorded as follow: • Technical facts about the selected landslide events, i.e. dimensions, materials, sequence of events, causes, etc. Special consideration made to the disastrous landslide events with multiple fatalities or other major social impact. These include the collapse of Highland Towers, Genting Highland debris flow, Gunung Tempurung slope failure, Pos Dipang debris flow, Paya Terubong rockslide, Sandakan landslide, Bukit Antarabangsa landslide, Ruan Changkul landslide, Taman Hillview landslide and Bukit Lanjan rockslide. • Consequences of the events such as fatality, economic loss, etc. • Press response, as evidenced by newspaper coverage and other publications. Response analysis will be based on quantification of newspaper columns (sizes in millimeters, etc.) • Government response, as evidenced by legislation or administrative actions taken after the event. An account is given of the existing slope safety measures being used in Malaysia and reference is made to the timing of their introduction with respect to the significant landslide events, including: • Slope safety vetting of environmental permit applications as well as for the approval of new development proposal – Town and Country Planning Department (JPBD), Department of Environment (JAS) advised by State and Federal Minerals and Geoscience Department (JMG) • Maintenance work and upgrading work on slopes along federal highways – Public Works Department (JKR) • Maintenance work and upgrading work on slopes along North South Expressway – PLUS Based on risk management thinking, a National Slope Safety System is outlined. 1.4 Limitation of Study There are several limitations identified on study being carried out due to limited time as well as documentation. Some of the limitations are: • Highly dependant on only two newspapers reports namely the New Straits Times and The Star may not reflect the actual situations pertaining to landslides in all over Malaysia as both newspapers main coverage are in Peninsular Malaysia. The landslides in East Malaysia may be not covered by them. • Newspapers also are selective in publishing news. • Data merely based on published literature as well as reports that are accessible. However, it is believed that there should be more information and data available which were not accessible due to restrictions or limited time available for research. • Some data rely heavily on online information such as data from World Bank as well information on some Ministries in Malaysia. It is assumed that all the information provided is correct and accurate. 2 Slope Safety System for Malaysia 1.5 Arrangement of Dissertation This dissertation is divided into five chapters. The first chapter (this chapter) briefly gives background, objectives and outline of the study carried out. Chapter 2 review the landslide hazards in Malaysia happened between 1990 and 2004. Chapter 2 also discusses the existing slope management measures being used in Malaysia. Chapter 3 presents the responses from the press and government toward landslide events. Study on the press response was made based on selected local newspapers while the government responses are based on steps and actions taken by the government after such events. Chapter 4 deals with an approach to setting up a National Slope Safety System for Malaysia based on risk management approach. Lastly, Chapter 5 presents the conclusion of the study made. 3 Slope Safety System for Malaysia CHAPTER 2 2.1 LANDSLIDE HAZARDS IN MALAYSIA General Overview The earliest written record of landslide in Malaysia is of which the writer is aware is the rockfall that occurred on 7 December 1919 at Bukit Tunggal, Perak, which claimed 12 lives and damaged property (Komoo, 1997). However, this chapter will only review some of the landslides occurred in Malaysia between 1990 and 2004. The landslides events within this period was selected simply because the landslides that occurred between 1990 and 2004 have better information in term of published literature as well much publicized and received more attention from the government as well as the public. Table 2.1 summarises some recorded landslide events in Malaysia between 1990 and 2004. The selected landslides which were reviewed are the ‘high profile’ landslide events in term of press coverage and consequences. Along with information about losses, this review also attempts to record basic technical information about the selected landslides based on published literature and available archival data. The term landslide and slope failure in this study are used interchangeably but carried same meaning i.e. “the movement of a mass of rock, debris or earth down a slope” based on Cruden (1991). The terminology used throughout this dissertation also consistent with the suggested methods and the glossary of the UNESCO Working Party (WP/WLI 1990, 1991, 1993; WP/WLI and Canadian Geotechnical Society 1993) in Turner & Schuster (1996) Table 2.1: Some recorded landslides between 1990 and 2004 (after Chan, 1998; Utusan Malaysia, 12/10/2004; New Straits Times, 2003 and The Star, 1996a) Date 11.12.1991 17.10.1993 24.10.1993 14.11.1993 23.11.1993 28.11.1993 11.12.1993 15.12.1993 21.12.1993 22.12.1993 Location Km 47, KL - Karak Highway, Pahang Km 32, Jalan Pahang to Cameron Highland, Pahang Km 58, Kuala Lipis – Gua Musang road, Kelantan Km 32, Jalan Bentong-Kuala Lumpur Km 25.5, KL - Karak Highway, Pahang Km 63, KL - Karak Highway, Pahang Highland Towers, Selangor Fatalities (No) Injuries (No) Consequences 0 0 0 0 No record No record 1 15 No record 0 0 2 48 0 0 0 2 0 0 0 0 0 0 No record Road closure for 2 days. No record Hundreds homeless and injured 9 cars buried House/cars swept away No record 0 0 28.12.1993 31.12.1993 22.03.1994 02.05.1994 11.11.1994 Kuala Lipis, Pahang Km 11, Jalan Puchong, Selangor Km 9, 20, 24, 25 and 26 of East-West Highway, Kelantan Km 62 and 70, Kuala Krai – Gua Musang road, Kelantan Kg Lereng Bukit, Miri, Sarawak Km 59.5, East-West Highway, Kelantan Fraser Hill, Pahang Puchong Perdana, Selangor Km 32, East-West Highway, Kelantan 0 1 0 3 0 0 3 0 0 0 15.11.1994 30.06.1995 05.07.1995 Km 33, East-West Highway, Kelantan Genting Sempah, Selangor Rockfall, Batu Pahat, Johor 0 20 0 0 22 0 18.08.1995 Km 92 – 97, KL – Kuala Lipis road, Pahang Hong Seng Estate Penang Hill area, Penang Taman Bukit Teratai, Ampang, Selangor 0 0 1 car damaged. Road closure for 1 day. 300 persons evacuated. A car damaged Part of a hotel damaged 10 families evacuated. Road closure for days. Tens stranded Road closure for days. Tens of vehicles damaged 4 houses and 3 factories destroyed. 12 houses damaged No record 0 0 0 0 0 0 No record No record No record 25.12.1993 18.09.1995 19.09.1995 24.09.1995 4 Slope Safety System for Malaysia Table 2.1: continued 16.10.1995 24.10.1995 31.10.1995 09.11.1995 20.11.1995 Bukit Tunku, Kuala Lumpur Tringkap, Cameron Highland, Pahang Tapah – Cameron Highland road, Perak Teluk Bahang, Penang Km 27, Bahau – Tampin road, N. Sembilan Km 61, Bailey Bridge, Kuantan – Maran road, Pahang Km 19, Hulu Yam Baru – Sg Tua road, Selangor Jalan Belading, Tangkak, Johor Cameron Highlands, Pahang Km 303.8, North-South Expressway, Gunung Tempurung, Perak 0 1 0 0 0 0 0 0 0 0 No record A house damaged. Road closure for 2 days 2 house damaged No record 0 0 No record 0 0 0 7 1 0 0 1 44 3 Tens 2 300 Tens Villagers relocated 0 0 0 0 Hundreds evacuated. No record 18.10.1996 18.10.1996 11.05.1997 28.11.1998 08.02.1999 15.05.1999 Pos Dipang, Perak Kuala Terla, Cameron Highlands, Pahang Keningau, Sabah (part of Gregg Typhoon) Hye Keat Estate Kg Chengkau Hilir, Rembau, N. Sembilan Cameron Highlands, Pahang Gelang Patah, Johor Pantai Dalam, Kuala Lumpur Paya Terubong, Penang Kg Gelam, Sandakan, Sabah Bukit Antarabangsa, Selangor A car damaged. 2 persons injured No record Few houses damaged 2 weeks of expressway closure and 3 months of road diversion. Whole village relocated Few houses damaged 0 1 1 0 17 0 0 0 4 0 0 0 28.11.1999 Bukit Aman, Penang 0 0 3.12.1999 Km 449.6, North South Expressway, Sg Buloh, Selangor 0 0 13.12.1999 Km 52, Johor Bahru - Ayer Hitam road, Johor Km 81.6, Tanah Rata – Brinchang road, Cameron Highland, Pahang Km 16.1, North South Expressway, Skudai, Johor Sg. Chinchin, Gombak, Selangor Gunung Pulai debris flow, Johor Ruan Changkul, Sarawak Taman Hillview, Selangor Km 21.8, North Klang Valley Expressway, Bukit Lanjan, Selangor Km 52, Tapah-Ringlet road, Cameron Highland, Perak Km 302, North South Expressway, Gunung Tempurung, Perak 0 0 16 families evacuated 6 families evacuated 19 families eacuated 17 vehicles buried Squatters were relocated 1,000 people evacuated and 15,000 people stranded. 1 day of road closure. 15 cars/1 bus/1 motocycle damaged Thousands of vehicles stranded. 1 day of road closure No record 6 0 0 0 1 5 16 8 0 0 2 0 5 0 0 0 A house partly destroyed A house destroyed Long houses relocated A bungalow destroyed 6 months of traffic diversions and massive jams in KL Main road cut off for hours 0 0 Road closure for 2 days. 21.12.1995 23.12.1995 25.12.1995 Dec 1995 06.01.1996 02.09.1996 09.10.1996 26.12.1996 Oct 1996 15.10.1006 09.01.2000 18.01.2001 22.09.2001 Dec 2001 28.01.2002 20.11.2002 26.11.2003 24.02.2004 11.10.2004 2.2 15,000 people stranded for hours No record Physiography and Geology According to International Comission on Irrigation and Drainage (ICID), Malaysia covers an area of about 329,758km2 occupying the Malay Peninsula, which lies on the southern shores of the Asian land mass, and the states of Sabah and Sarawak in the northwestern coastal of Borneo Island. The two regions are separated by about 531km of the South China Sea. Peninsula Malaysia, covering 131,598km2, has its land frontier with Thailand to the north, and is connected to Singapore by a causeway in the south. The state of Sabah covering 73,856km2 and the state of 5 Slope Safety System for Malaysia Sarawak covering 124,989km2 bordered the territory of Indonesian’s Kalimantan and has land frontiers with two enclaves which make up Brunei. Peninsula Malaysia consists of steep hills and mountains ranges, rolling to undulating land the coastal and riverine flood plains. The hill and mountain ranges cover about one-third of the plain surface of the Peninsula and run more or less parallel to the long axis of the country. The rolling to undulating land is found generally at the seaward flanks and the intervening areas between mountain ranges. Although not very extensive coastal plains and alluvial terraces are found from 15 to 65 km inland from the coast with levels rising to 75m above mean sea level. The riverine flood plains are found as narrow belts of alluvium gently sloping away from the major rivers. Towards the coast they merge with marine alluvium of the coastal plains. Sabah is surrounded on three sides by seas. The physical pattern consists of narrow alluvial coastal plains backed by hilly forested areas. The mountain of the interior has acted as barriers to inland penetration. The coastal plains and river valleys consist of marine and fluvial alluvium. Although the coastal plains form a small proportion of the total area they have the most important parts of the state in terms of settlement and agricultural and economic development. Sarawak consists of a flat and swampy coastal area and steepy undulating hills in the interior. The coastal plains comprise deep peat and muck soils, and at various points along the coast “raised beaches” occur some distance inland from the coastline. The physiography of Malaysia is also controlled by the geology where variety rock types of igneous, sedimentary and metamorphic can be found. Deep weathering profile is common where the weathered rocks on the sloping ground are prone to landslides especially during and after heavy downpour. Most of the slope areas are also covered with thin colloviul deposits. On the low lying ground especially near coastal areas, the ground consists of Quaternary marine deposits. The only comprehensive publication available on geology of Peninsula Malaysia presented in a single volume was those edited by Gobbett & Hutchison (1975) while the geology of Sabah and Sarawak is presented in more recent publication by Hutchison (2005). However, the Department of Minerals and Geoscience, then known as Geological Survey Department did publish and update details maps and reports on specific areas from time to time. 2.3 Climate and Rainfall The climate and rainfall information of Malaysia can be found from the website of Malaysian Meteorological Department (MMD) and the International Commission on Irrigation and Drainage (ICID). Malaysia lies near the Equator between latitude 1o and 7o north and between longitude 100o and 119o east. The country is subject to maritime influence and the interplay of wind systems, which originate in the Indian Ocean and South China Sea. The year is commonly divided into the southwest and northeast monsoon seasons. The climate of Malaysia is hot wet equatorial. The important features of the climate are the continuous warm temperatures and seasonal distribution of rainfall. Mean daily temperatures range from 21oC to 32oC in the lowlands throughout the year. Cooler temperatures prevail at the higher altitudes. Variation in rainfall distribution is the most significant environmental variable. Generally, most if not all parts of Malaysia experience moisture deficits during one or more periods of the year. Conversely, excessive rainfall could occur. There is considerable variation in the averages of annual and monthly distribution of rainfall by location. The average annual rainfall ranges from 1,500mm to 4,000mm with the states of Sabah and Sarawak about 20% to 40% more rainfall than Peninsula Malaysia. Figure 2.1 presented general annual rainfall distribution in Malaysia for the year 2000. 6 Slope Safety System for Malaysia Figure 2.1: Annual rainfall distribution (in cm) in Malaysia for the year 2000 (after MMS). The seasonal variation of rainfall in Peninsula Malaysia is of three main types: • Over the east coast districts, November, December, January are the months with maximum rainfall, while June and July are the driest months in most districts. • Over the rest of peninsula with the exception southwestern coastal area, the monthly rainfall pattern shows two period of maximum rainfall separated by two periods of minimum rainfall. The primary maximum generally occurs in October-November while the secondary maximum generally occurs in April-May. Over the northwestern region, the primary minimum occurs in January-February with the secondary minimum in JuneJuly while elsewhere the primary minimum occurs in June-July with the secondary minimum in February. • The rainfall pattern over the southwestern coastal area is much affected by early morning “Sumatras” from May to August with the result that the double maximum and minimum pattern is no longer discernible. October and November are the months with maximum rainfall and February the month with minimum rainfall. The March-April-May maximum and the June-July minimum are absent or indistinct. The seasonal variation of rainfall in Sabah and Sarawak can be divided into five main types: • The coastal areas of Sarawak and northeast Sabah experience a rainfall regime of one maximum and one minimum. While the maximum occurs during January in both areas, the occurrence of the minimum differs. In the coastal areas of Sarawak, the minimum occurs in June or July while in the northeastern coastal areas of Sabah, it occurs in April. Under this regime, much of the rainfall is received during the northeast monsoon months 7 Slope Safety System for Malaysia • • • • of December to March. In fact, it accounts for more than half of the annual rainfall received on the western part of Sarawak. Inland areas of Sarawak generally experience quite evenly distributed annual rainfall. Nevertheless, slightly less rainfall is received during the period of June to August which corresponds to the occurrence of prevailing southwesterly winds. It must be pointed out that the highest annual rainfall area in Malaysia may well be found in the hillslopes of inland Sarawak areas. Long Akah, by virtue of its location, receives a mean annual rainfall of more than 5,000mm. The northwestern coast of Sabah experiences a rainfall regime of which two maximum and two minimum can be distinctly identified. The primary maximum occurs in October and the secondary one in June. The primary minimum occurs in February and the secondary one in August. While the difference in the rainfall amounts received during the two months corresponding to the two maximum is small, the amount received during the month of the primary minimum is substantially less than that received during the month of the secondary minimum. In some areas, the different is as much as four times. In the central part of Sabah where the land is hilly and sheltered by mountain ranges, the rainfall received is relatively lower than other regions and is evenly distributed. However, two maximum and two minimum can be noticed, though some what less distinct. In general, the two minimum occur in February and August while the 2 maximum occur in May and October. Southern Sabah has evenly distributed rainfall. The annual rainfall total received is comparable to the central part of Sabah. The period February to April is, however slightly drier then the rest of the year. 2.3.1 Rainfall-Landslide Relationship The relationship of rainfall and landslides are well accepted in humid tropical and sub-tropical countries. The historical rainfall and landslides databases can be analysed to produce statistical relationship between rainfall intensity and landslide frequency. There are attempts been made by some researchers in the past such as Raj (2000) and Faisal (2000) to record the rainfall-landslide relationship. Raj (2000) presented correlation between landslides reports in local newspapers in the granitic bedrock areas of the Peninsula Malaysia between 1981 and 1998. It showed a disproportionate pattern with some years having considerably reports more than the other (Figure 2.2). He concluded that when this pattern is compared with the total annual rainfall of selected stations for the same period, there is a distinct correlation with the years having large number of reports coinciding with the years having relatively high annual rainfalls. However, rainfall data in not given. Correlation between rainfall and landslide should only be attempted where local rainfall data is available and the exact time of the landslide is known. These requirements are rarely met. 8 Slope Safety System for Malaysia Figure 2.2: Relationship between local newspaper reports on landslides in the granitic bedrock areas of Peninsular Malaysia (1981-1998) and years, months and locations as an attempt to relate with raining seasons (after Raj, 2000) 2.4 Major Landslide Events (1990-2004) Several landslides happened between 1990 and 2004 can be considered as major landslide events. The general locations of these landslides are presented in the Malaysian map in Figure 2.3. 9 Slope Safety System for Malaysia 2.4.6) Sandakan landslide 2.4.5) Paya Terubong rockslide 2.4.3) Gunung Tempurung slope failure 2.4.4) Pos Dipang debris flow 2.4.1) Highland Towers collapse 2.4.2) Genting Sempah debris flow 2.4.7) Bukit Antarabangsa landslide 2.4.9) Taman Hillview landslide 2.4.10) Bukit Lanjan rockslide 2.4.8) Ruan Changkul landslide Figure 2.3: Map of Malaysia showing location of major landslide events between 1990 and 2004 2.4.1 The Collapse of Highland Towers (11 December 1993) There are numerous publications referred or discussed the technical facts of the collapse of Highland Towers. The most authoritative is the Report of the Inquiry Committee into the Collapse of Block 1 and the Stability of Blocks 2 and 3, Highland Towers Condominium, Hulu Kelang, Selangor published by the Ampang Jaya Town Council (Majlis Perbandaran Ampang Jaya – MPAJ, 1994). The report concluded that the most probable cause of collapse was due to the buckling and shearing of the rail piles foundation induced by the movement of the soil. The movement of the soil was the consequence of retrogressive landslides behind the building of Block 1. According to the report (MPAJ, 1994), the landslide was triggered by inadequate drainage on the hill slope that had aggravated the surface runoff. Cut and fill Slope and rubble walls behind and in front of Block 1 were also found to be not properly designed with Factor of Safety of less than 1, nor their construction properly supervised. The total length of the landslide was 120m while the width of surface of rupture is about 90m, involving approximately 40,000 m3 of debris. Faisal (2000) mentioned that there had been a period of intense and prolonged rainfall in the area on the night and hours before the landslide. The rainfall records from nearby gauging stations showed that heavy rainfall started in early November and this was maintained until the day the building collapsed. From 1st September the cumulative rainfall for the stations is between 800mm and 900mm. Aerial inspections suggested that there were four retrogressive slips immediately behind the collapsed structure. Figure 2.4 and 2.5 showed the cross-section of the area before and after the landslide. Plate 2.1 showed the minutes during the collapse while Plate 2.2, 2.3 and 2.4 showed the aftermath of the incident respectively. Some other discussions were made by Othman et al (1994), Nik Hassan (1995), Komoo (1997) and Gue & Tan (2002). Nik Hassan (1995) recorded, ‘on December 11, 1993 at approximately 10 Slope Safety System for Malaysia 1.30pm on Saturday, Block 1 of the Highland Towers Condominium suddenly toppled over and collapsed. Three victims were rescued and alive on the first day; a maid Mrs. Umi Rashidah Khairuman with her 2-year old baby daughter and a 56-years old Japanese lady occupant, Mrs. Shizumi Nakajima. The latter succumbed to the injury and died in Kuala Lumpur General Hospital on the same day. After 10 days and night the search and rescue efforts failed to find any more victims who are still alive. A more drastic means was then employed to locate and extricate the bodies. In all, 48 bodies were recovered and identified’. Figure 2.4: Original cross-section through Block 1 of Highland Towers condominium (after MPAJ, 1994) Figure 2.5: Cross section showing sequence of retrogressive landslides (after MPAJ, 1994) 11 Slope Safety System for Malaysia Plate 2.1: The collapse of Block 1 of Highland Towers condominium (after MPAJ, 1994) Plate 2.2: The aftermath of the collapse of Block 1 of Highland Towers condominium (MPAJ, 1994) 12 Slope Safety System for Malaysia Plate 2.3: View of Highland Towers area on the first night after the collapse (MPAJ, 1994) Plate 2.4: View of Highland Towers months after the collapse (New Straits Times, 1993) 2.4.2 Genting Sempah Debris Flow (30 June 1995) Chow et al (1996) reported, ‘the afternoon of June 30, 1995, heavy rainfall in the Genting Sempah area caused the Karak Highway Tunnel to be flooded; traffic was diverted via the slip road linking the Kuala Lumpur – Karak Highway to Genting Highlands Resort. The heavy downpour triggered a series of landslides, followed by debris flow which swept away 19 vehicles, resulting in the loss of 20 lives with one missing and 23 others injured. Investigation showed that thunderstorm had caused another 72 landslides between km 1 and km 8 along the access road to Genting Highland Resorts’. Komoo (1997) highlighted, ‘a few minor landslips had caused the vehicles to stop, making them ready ‘prey’ for the debris flow. This coincidence of events actually led to the high numbers of deaths’. 13 Slope Safety System for Malaysia Chow et al (1996) also reported, ‘the debris flow was the culmination of three landslides occurring near the headwaters of the stream. Debris from two landslides, one on the western bank near the middles reaches of the stream and the second occurring near the headwaters of the stream, was deposited on the valley floor, causing an impounding of the stream waters. Later the impounded stream broke through the debris causing a debris flow of water, mud, boulders and fallen trees. Komoo (1997) reported, ‘the debris flowed from 800m elevation to 570m, over the total length of approximately 1km. The estimated amount of debris moved was 3,000m3’. Othman (1996) mentioned similar observation plus rainfall analysis in relation with the event. He stated that ‘the month of June 1995 was abnormally wet over Genting Sempah area. A total rainfall of 428.5mm recorded was the highest in 20 years, approximately 2.6 times the June long term average rainfall of 163.2mm. The 6-day accumulated rainfall ending on 30th June 1995 was recorded at 207.5mm, constituting approximately 50% of the monthly total and exceeding the June long term average of 163.2mm by 27%. Such high antecedent rainfall which occurred within the debris flow catchment was responsible for extreme wetting of the soil prior to the 30th June storm’. Figure 2.6 and 2.7 showed the location plan of the area and the debris flow plan respectively while Plate 2.5 and 2.6 showed the aftermath view and schematic diagram of the event. Figure 2.6: Location plan of Genting Sempah debris flow (after Chow et al, 1996) 14 Slope Safety System for Malaysia Figure 2.7: Plan view of the Genting Sempah debris flow (after Chow et al, 1996) 15 Slope Safety System for Malaysia Plate 2.5: The aftermath of Genting Sempah debris flow (Sunday Star, 2/7/1995) Plate 2.6: Schematic diagram of the Genting Sempah debris flow (New Straits Times, 1/7/1995) 2.4.3 Gunung Tempurung Slope Failure (6 January 1996) The then Geological Survey Department (Jabatan Penyiasatan Kajibumi) (1996) reported, ‘at about 7.30am on 6 January 1996, a section of a cut slope at km 303.8 of the North South Expressway near Gunung Tempurung, Kampar, Perak failed’ (Plate 2.7 and 2.8). Debris from this 16 Slope Safety System for Malaysia landslide which consisted of a mixture of earth, rocks and shotcrete materials swept a container truck off the road, killing the co-driver of the truck. Two smaller retrogressive landslides occurred at the crown of the first landslide, with one occurring at 11.20am and the other at 12.42pm. The length of the displaced mass was 82m. The depth of surface of rupture was 22m while the width of surface of rupture was 65m. The report also revealed that; ‘i) the area has had a history of landslide, ii) the expressway was constructed along a highly sheared and fractured zone, that is, a zone of natural inherent weakness displaying numerous relict structural planes in the rocks. The landslide occurred along a sheared zone where the rocks are highly fractured, and the weathered rocks and soil cover are thick and, iii) the landslide site is underlain by granite, schists and hornfels. Soils developed from these rock types have different engineering properties. Although there was no rainfall at the time of the landslide occurrence, it was reported in the press that there was some accumulation of water at the top of the slope due to earlier rainfall’. Figure 2.7 and 2.8 showed the location plan and the cross-section of the area. Figure 2.8: Location plan of Gunung Tempurung slope failure (after Geological Survey Department, 1996) 17 Slope Safety System for Malaysia Figure 2.9: Cross-section of the slope failure at Gunung Tempurung (after Geological Survey Department, 1996) Plate 2.7: Gunung Tempurung landslide, North South Expressway (after Jamaludin, 2005) 18 Slope Safety System for Malaysia Plate 2.8: Closer view of Gunung Tempurung landslide, North South Expressway (after Jamaludin, 2005) 2.4.4 Pos Dipang Debris Flow (30 August 1996) Komoo (1997) gives a graphic account of a debris flow in Pos Dipang in 1996. He recorded, ‘the awesome force that assailed the unsuspecting village at Pos Dipang, Perak near dusk on August 30, 1996 struck fear in the hearts of those who beheld the aftermath. The fury of nature had devastated almost a whole village and had scoured trees, soil, rocks and everything that stood in its way for more than 5km. The same power that hurled mature tropical trees like matchsticks also demolished houses and swept 44 people into its roaring waters’. Komoo (1997) continued his explanation on the above event by highlighting, ‘the excessive rain initiated the event that occurred that fateful day. A total of 461mm of rain fell on the area in the month of August 1996, as compared to 137mm in 1993 and 281mm in 1995. The copious amount of rains in the predominantly hilly area softened the ground which subsequently triggered several large landslides on the steep slopes upstream of Sungai Dipang. The debris and mud resulting from the landslide entered the river channel, creating a huge mudflow. The force and momentum of the mudflow excavated rock, soil and boulders in the river channel as well as along the banks, thus uprooting huge trees. The stupendous amount of debris caused extreme river bank erosion. At several constrictions and turns in the river the tree trunks and branches formed temporary dams which held the torrent of water momentarily. Field evidences indicated that one of these temporary dams was formed about 200m upstream of Pos Dipang. This dam broke when it could no longer withstand the ever increasing force of swelling waters, suddenly releasing a tremendous amount of water and debris, thus creating a huge debris flood, which deluged the village’. Figure 2.10 presented the field sketch of the area while Plate 2.9 and 2.10 showed the aftermath of the event. 19 Slope Safety System for Malaysia Figure 2.10: Field sketch of Pos Dipang debris flow (courtesy of Dr. Tajul Anuar Jamaludin) Plate 2.9: The aftermath of Pos Dipang debris flow (courtesy of Dr. Tajul Anuar Jamaludin) 20 Slope Safety System for Malaysia Plate 2.10: The debris flow path at Pos Dipang (courtesy of Dr. Tajul Anuar Jamaludin) 2.4.5 Paya Terubung Rockslide (28 November 1998) On November 28, 1998 at about 4.45pm, a massive rockslide occurred in a cut slope at Paya Terubong, Penang. Mahmud & Baba (2002) stated, ‘massive rock slides, tons of boulder and earth has slide down on to the parking area of the adjacent Block 8 of the Sun Moon City Apartments, blocking Jalan Bukit Kukus. Due to the landslide, 17 vehicles parked by the roadside were buried’. Plate 2.11 and 2.12 showed the consequence of the event. Mahmud & Baba (2002) also stated, ‘aerial photographs taken on 5th and 19th December 1998 indicate that there were massive land clearance and human activities near the top of the hill. Upon site verification, the land has been cleared and planted with durian trees, lemon grass and other type of cultivation. Two scars of landslide of with an average size of width of surface of rupture of 25m and length of displaced mass measuring 20m are seen on the slope near the top of the hill on the northeastward of the failed area. Beside the scar that cause the rock fall on the 28th November 1998, there are landslides located on the northern and southern steep cut slope as indicated in the December 1998 aerial photographs’. Faisal (2000) stated, ‘the slip occurred on a cut slope at an angle close to 60o. The total height of the original slope was approximately 120m with huge boulders scattered on the surface of the slope covered by trees and shrubs. A total of about 400 boulders ranging from 2m to 10m in diameter were found scattering in the area. From the daily rainfall record, the area was subjected to heavy rainfall few days before the slide. The rainfall data from various stations indicated that the month of November seemed to be one of the wettest months with the monthly rainfall intensity of up to 850mm’. 21 Slope Safety System for Malaysia Plate 2.11: Paya Terubong rockslide (Jamaludin, 2005) Plate 2.12: Closer view of Paya Terubong rockslide. Note the damaged cars (Jamaludin, 2005) 22 Slope Safety System for Malaysia 2.4.6 Sandakan Landslide (7 February 1999) The Borneo Post (1999) reported, ‘17 bodies were dug up from the rubbles of four houses buried under tons of mud and 2 were injured during a landslide in a natural slope which hit squatter colony at the foothill opposite the general post office off mile ½ Leila Road. The tragedy occurred about 4.00am after heavy downpour since late last night while most of the residents of the colony were still asleep. Soil erosion sent tons of mud and trees downhill, completely burying the four houses below in the colony resided by most foreigners. The district has been experiencing bad weather for more than one week. All the remaining residents at the colony were ordered to evacuate to the community centre for safety reason together with their belongings’. Plate 2.13: The aftermath of the Sandakan landslide (The Borneo Post, 1999) Plate 2.14: The search and rescue after the landslide in Sandakan (The Borneo Post, 1999) 23 Slope Safety System for Malaysia 2.4.7 Bukit Antarabangsa Landslide (15 May 1999) On May 15, 1999 at approximately 5.30am, a massive landslide in a cut and fill slope which was combination of several smaller landslides occurred at Bukit Antarabangsa, Selangor. The landslide force evacuation of almost 1,000 residents and cut off access to the hilly areas where more than 10,000 people were stranded in their own houses. Mahmud & Baba (2002) highlighted, ‘massive landslide, tons of earth and granitic boulders have fallen down on to the only access road to Bukit Antarabangsa. The landslide buried a passing vehicle but fortunately the driver escape with minor injury. The landslide located about 100m to the west of the Wangsa Height condominium’. Faisal (2000) stated, ‘the volume of the landslide was estimated to be 14,580m3. The slide had brought down about 70m stretch of Wangsa 3 road. Another landslide occurred the day before, May 14, 1999, at about 4:30pm, on a steep slope adjacent to the Athenaeum at The Peak condominium. The landslide scar measured about 31m wide of surface rupture and 140m long of centre line, from crown to the toe of the slide. The supersaturated slide debris of about 13,000m3 piled up at the toe of the slope, occupying area of about 50m wide and 100m long of displaced masses’. Kumpulan Ikram Sdn Bhd (1999) reported, ‘the most probable causes of slope failure can be attributed to the following factors; the slope has minimum Factor of Safety 1.00 to 1.35 which is lower than the required Factor of Safety 1.4 for slope adjacent to high rise building and the slope was not properly constructed as indicated by the presence of relatively weak material in the body of the slope and there is no indication of berms drain construction within the failed section of the slope. The others contributing factors are; i) infiltration and ingress of water into the soil during prolonged rainfall, ii) lack of maintenance to the slope as evidence by the blocked drains and previous un-repaired cracks in drains, iii) deposition loading on the slope by dumping activity, iv) vegetation removal by dumping activity on the slope increased surface erosion, v) internal erosion of the base of fill materials due to improper treatment of the original seasonal stream, and vi) prolong rainfall resulting the water table to rise and intercept the ground surface. Spring formed at the intercepting point, which is actually headwater of seasonal stream flow’. Figure 2.11 and 2.12 presented the location plan and cross section of the area while Plate 2.15 and 2.16 showed the landslides. Faisal (2000) also stated that there was an intense rainfall for a few hours before the first landslide occurred (4.30pm on 14th May 1999). A total of 32.8mm of rain was recorded between 3.00pm to 4.00pm on that day. Between 1.00am on 13th May to 4.00pm on 14th May, a total of 90.2mm of rain was recorded with a peak hourly rainfall of 31.9mm between 1.00am to 2.00am on 13th May 1999. The second landslide (5.30am on 15th May) occurred 13 hours later. The rainstorm on 14th May 1999 prior to the landslide was preceded by a heavy rainstorm on the 12th May 1999 with 80.5mm of rain. A total of 308mm of rain was recorded 13 days before the landslide. 24 Slope Safety System for Malaysia Figure 2.11: Landslides surrounding Ampang, Ulu Klang area. Landslide 1 at Taman Hillview, Landslide 2 at Highland Towers condominium, Landslide 3 at Athenaeum at the Peak condominium and Landslide 4 at the Wangsa Heights condominium (after Komoo, 2004) Figure 2.12: Typical cross-section of the Bukit Antarabangsa landslide (after Kumpulan Ikram Sdn Bhd, 1999) 25 Slope Safety System for Malaysia Plate 2.15: The first Bukit Antarabangsa landslide near Athenaeum at the Peak condominium (courtesy of Dr. Tajul Anuar Jamaludin) 26 Slope Safety System for Malaysia Plate 2.16: The second Bukit Antarabangsa landslide near Wangsa Height condominium (courtesy of Dr. Tajul Anuar Jamaludin) 2.4.8 Ruan Changkul Landslide (28 January 2002) Sarawak’s worst known landslide occurred when a catastrophic collapse in a cultivated slope destroyed an eight-door long house and two nearby houses, and claimed 16 lives in the incident at Ruan Changkul, Simunjan on January 28, 2002 (Hashim & Among, 2003). Hashim & Among (2003) recorded, ‘the length of the ruptured surface is 170m from crown to foot. The maximum width of scar is 40m whereas the depth to the ruptured surface ranges from 2m to 9m deep. The main body is considerably flatter than the top. The failed mass consists of large amount of debris with an approximate volume of 20,000m3 to 22,000m3 of wet slurry, 27 Slope Safety System for Malaysia which indicates very high infiltration. The failed mass ends approximately 100m from the top of surface of rupture to the toe marked by a 3m drop-off to undisturbed ground at the valley side. The daily rainfalls recorded at nearby stations within the month of January 2002 were between 0.5mm to 185mm. The area had the greatest amount of precipitation on 28th January 2002 i.e. 169mm recorded at the nearest station of Sg. Pinang; which resulted in the landslide and flood in the area’. Figure 2.13 presented the cross section and plan view of the area. Plate 2.17 and 2.18 showed the aftermath of the landslide. Figure 2.13: The cross section (top) and plan view (bottom) of the Ruan Changkul landslide respectively (after Hashim & Among, 2003) 28 Slope Safety System for Malaysia Plate 2.17: Ruan Changkul Landslide, Sarawak (after Hashim & Among, 2003) Plate 2.18: Closer view of Ruan Changkul Landslide, Sarawak (after Hashim & Among, 2003) 2.4.9 Taman Hillview Landslide (20 November 2002) Komoo (2004) recorded, ‘on 20 November 2002 a bungalow house in Taman Hillview, Kuala Lumpur was engulfed by a landslide event which caused the death of 8 people. The house is situated at the foot of a hill slope which had been terraced for development then abandoned. The Highland Towers condominium is few hundreds metres west of the same hillside. The rapid landslide event (less than 4 minutes) generated debris that destroyed and covered the house, 29 Slope Safety System for Malaysia trapping all its inhabitants. Five out of the 13 people trapped were saved within 24 hours after rescue work began’. According to Komoo and Lim (2003), ‘the landslide was a complex landslide, i.e. a combination of rotation at the head and sliding in the middle which was followed by a flow occurrence at the toe. The total length of the landslide was up to 200m and 50m of the surface rupture width, involving approximately 25,000m3 of disturbed slope material. Even though continuous heavy rain triggered the sliding, various other important factors that contributed to the event were its location within an old landslide, superficial material prone to failure, geological lineament that facilitated sliding, shape of the old landslide that aided the accumulation of groundwater, leveling and terracing at the upper part of the landslide area, and an old damaged rubble wall that encouraged the concentration of surface water. The landslide was apparently a recurrence of an old landslide’. Figure 2.14 showed the engineering geological plan while Figure 2.15 showed the oblique view of the landslide respectively. Plate 2.19 showed the aftermath of the landslide. Figure 2.14: Engineering geological plan of Taman Hillview landslide showed common features (top) and distribution of inhomogenous materials after the failure (bottom) (after Komoo & Lim, 2003) 30 Slope Safety System for Malaysia Plate 2.19: The aftermath of Taman Hillview landslide (courtesy of Dr. Tajul Anuar Jamaludin) Figure 2.15: The oblique view of Taman Hillview landslide (after Komoo & Lim, 2003) 31 Slope Safety System for Malaysia 2.4.10 Bukit Lanjan Rockslide (26 November 2003) The failure occurred on 26 November 2003 at approximately 7.16am at kilometer 21.8 of the Bukit Lanjan Interchange on the New Klang Valley Expressway (NKVE) in a road cut slope (Komoo et al, 2004). They reported, ‘the rock slope failure involved an estimated 35,000m3 of rock debris, mainly angular blocks of various sizes, which came to rest on the expressway. The failure materials blocked the entire expressway forcing the closure of the road to the public for more than six months. The failure at Bukit Lanjan occurred on the steep cut slope on the southern end of an approximately north-south trending cut. The failed slope incorporated six benches reaching to a height in excess of 65m from road level. The failure surface was shaped like a wedge, where northern margin of the failure exposed a continuous major discontinuity (most likely fault plane), while the southern end was obscured by rock debris. Individual rock blocks within the debris had an estimated volume of up to about 200m3. The crest of the failure had a stepped, almost vertical face, apparently controlled by another major discontinuity’. Komoo et al (2004) also mentioned, ‘the analysis shows that the unusual prolonged rainfall prior to the failure event may have been the triggering factor for the rock slope failure. They also highlighted that in any case, the actual causal factors could be more complex that what was deduced, i.e. unfavourable discontinuity orientations and hydrostatic pressure. One of the most usually important causal factors, particularly in the wet tropical terrain, is deterioration of rock mass properties or the weakening of the rock mass strength through time, by both physical and chemical weathering’. Figure 2.16 showed the location plan of the area while Plate 2.20 and 2.21 showed the rockslide. Figure 2.16: Location of Bukit Lanjan rockslide (after Jamaludin, 2005) 32 Slope Safety System for Malaysia Plate 2.20: Aerial view of Bukit Lanjan rockslide (after Jamaludin, 2005) Plate 2.21: Bukit Lanjan rockslide (after Jamaludin, 2005) 33 Slope Safety System for Malaysia 2.5 Landslide Fatality Data and Analysis There are two common indicators used to review any disaster impact i.e. the economic loss and human loss. For this study, only human loss is considered and fatality data was obtained from published literature or newspaper cuttings as presented in Table 2.1. No attempt has been made to find data on economic loss. The landslide fatalities between 1990 and 2004 are shown in Figure 2.17 to 2.19 and comparison being made with gross domestic product (GDP) annual growth rate, urban population growth and total population growth. The latter data is from the Population Division of the Department of Economics and Social Affairs of the United Nations Secretariat (2005a and 2005b) (Appendix A). Study was also carried out to check reports by the Central Bank of Malaysia (2005) and the Ministry of Finance (2005). Unfortunately, both reports did not provide long term data. 200 12 180 10 160 8 fatalities (numbers) 140 6 fatalities GDP annual grow th cumulative fatalities 120 4 2 100 0 80 -2 60 -4 40 -6 20 -8 0 GDP Annual Growth (percentage) GDP Annual Growth Rates versus Landslides Fatalities -10 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 years Figure 2.17: GDP annual growth rates versus landslides fatalities Urban Population Growth versus Landslides Fatalities 18 200 fatalities 16 urban population grow th 160 14 cumulative fatalities fatalities (numbers) 140 12 120 10 100 8 80 6 60 4 40 2 20 0 0 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 years Figure 2.18: Urban population growth versus landslides fatalities 34 2005 Urban population growth (millions people) 180 Slope Safety System for Malaysia Total Population versus Landslides Fatalities 200 30 fatalities cumulative fatalities 140 fatalities (number) 25 total population 160 20 120 100 15 80 10 60 40 total population (million people) 180 5 20 0 0 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 years Figure 2.19: Total population growth versus landslides fatalities Apportionment of landslides between private and public land 60 200 180 public 160 private 40 140 cumulative fatalities 120 30 100 80 20 fatalities (number) cumulative fatalities (numbers) 50 60 40 10 20 0 0 1985 1987 1989 1991 1993 1995 years 1997 1999 2001 2003 2005 Figure 2.20: Apportionment of landslides events between private and public land Apportionment of landslides and type of facilities affected 60 200 160 Fatalities (numbers) road 140 village 40 120 cumulative fatalities 30 100 80 20 60 40 10 Cumulative fatalities (numbers) 180 building 50 20 0 0 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 years Figure 2.21: Apportionment of landslide events between types of facilities affected 35 Slope Safety System for Malaysia Figure 2.20 and 2.21 presented apportionment of landslides between public and private land as well as between types of facility affected respectively. The apportionments of private and public land were based on land ownership i.e. land on which landslide occurred. Based on recorded information, the total landslide fatalities in Malaysia between 1990 and 2004 are 186 people. However, these figures do not include the death-toll of 300 people after Gregg Typhoon demolished a village in Keningau, Sabah on 26 December 1996 as landslide occurred as part of other disaster. The trend of annual landslide fatalities should be obtained by 5-year or 10year rolling average but the data period is too short to allow this. Figure 2.20 indicated that the landslide fatalities on private land were higher as compared to public. The significant fatalities on public land basically due single event of Genting Sempah debris flow which killed 20 people. Based on Figure 2.21, observation can be made that the buildings (or engineered residential areas) located on hillslopes are the highest area prone to landslide risks while villages (or squatters/un-engineered residential development) are the second area prone to landslide risks. The roads (public or private expressways) seem the areas with the least landslide risks, in terms of loss of life. 2.6 Existing Measures on Slope Management Various government departments are involved directly or indirectly in slope management measures. Two main government departments involved directly, namely the Public Works Department (Jabatan Kerja Raya - JKR) and the Department of Mineral and Geosciences (Jabatan Mineral dan Geosains - JMG). Other government departments basically will get advice from these two departments. While JKR has in the past mainly focused on management of road slopes, the JMG mainly deals with new development plans. On the private sector, one organization with a slope management system is PLUS Expressway Bhd, the major concessionaire company who has the right on North-South Expressway and several other expressways. 2.6.1 Public Works Department (Jabatan Kerja Raya - JKR) The Public Works Department (Jabatan Kerja Raya - JKR) established Slope Engineering Branch (under Infrastructure Sector) in 2004 has a very wide remit to regulate, monitor, manage and carry out investigation of all road slopes and other slopes associated with the development of government projects in Malaysia. In practice it continues the functions of the former Slope Maintenance Unit of JKR Road Branch. It disburses funds to the States for upgrading of federal road slopes, inputs to landslide investigation, manages the slope catalogue and provides policy support. It also carries out studies. Based on Annual Report 2002/2003 (Jabatan Kerja Raya Malaysia, 2003), one of the studies undertaken by JKR in relation with slope management was the slope protection study for Federal Route 22, Tamparuli-Sandakan, Sabah. Comprehensive study was carried out for the assessment of slopes safety along the 300km road traverse the Crocker and Trusmadi Ranges. Primary objective is to provide the Government of Malaysia with slope management system based on risk management principles for the road. During the study, a slope management system named “Slope Management and Risk Tracking System” (SMART) was developed by Dr. Mohammad Asbi Othman, Dr. David M. Lloyd and Dr. Paul Wilkinson. The SMART system is a software package for slope information management system that includes data collection procedures, training aid, a 36 Slope Safety System for Malaysia database, a library of report and data, and as a web publishing tool for dissemination of information as well as a management tool. The former Slope Maintenance Unit has investigated a number of man-made slope ranking systems. Jamaludin et al (2004) briefly discussed and listed down various slope assessment systems being tested by JKR on various purposes, locations and conditions while Hussein et al (2004) discussed in further details the development and used of the various slope assessment systems. The systems being tested and/or used by JKR are Slope Maintenance System (SMS), Malaysian Engineered Hillslope Management System (MEHMS), Slope Priority Ranking System (SPRS), Slope Information Management System (SIMS) and Slope Management and Risk Tracking System (SMART). Two other JKR branches are involved with slope management: the Road Branch (Cawangan Jalan) under Infrastructure Sector and the Civil Engineering and Expert Branch (Cawangan Pakar) under Specialised Engineering Sector. The functions of Road Branch related to slope management among others are: • To process and decide on the distribution of the fund to build and maintain the roads to state JKR and local authorities, and • Maintain, manage and improve all federal roads, as well as coordinate the road maintenance concessions (programmes). Among the function of Civil Engineering and Expert Branch that related to slope management are: • To synergise the knowledge of the experts or specialists in JKR in overcoming the technical problems faced by the department and other government agencies, and • To institutionalize research and development in JKR. 2.6.2 Department of Minerals and Geoscience (Jabatan Mineral dan Geosains - JMG) The Department of Minerals and Geosciences (Jabatan Mineral dan Geosains - JMG) main involvement in slope management is presented in the 2004 Annual Report (Jabatan Mineral dan Geosains, 2004). Overall, the engineering geology activities had emphasized on the geological terrain mapping, engineering geology study and land use assessments for developments. Studies that had been done includes geological investigations for potential geohazard sites, engineering geology mapping at selected sites and consultation regarding landslides, rock falls, sink holes and land subsidences. The main activity for environmental geology is to provide geological inputs to assess development plan for Environmentally Sensitive Areas (ESA). Geological inputs were given via comments on Environmental Impact Assessments (EIA) report by the Department of Environment as well as via State Structure Plan, Local Plan and Subject Plan Reports by Town and Country Planning Department. Assistances were also given to other agencies viz. local authorities in monitoring development projects and National Resource and Environmental Board of Sarawak (NREB). Land use assessments were provided to government agencies pertaining environmental impacts from proposed development projects. The assessments were made in view of geology, engineering geology, hydrogeology, geological heritage sites and environmentally sensitive areas. There are two main programmes related directly with slope management as listed the 2004 Annual Report as follow: 37 Slope Safety System for Malaysia 2.6.2.1 National Geohazards Study Two developments projects viz. National Geohazards and Integrated Geology and Geotechnics were carried out. The National Geohazards Project was carried out in the states of Sarawak, Pahang, Pulau Pinang and Selangor/Federal Territory Kuala Lumpur. Under the Integrated Geology and Geotechnic Project, Eight Malaysia Plan, site investigations, geological terrain mapping and advisory services were carried out in Sabah. In Selangor and Penang, the Local Governments had stipulated engineering geology assessments by JMG to be part of the condition in the Proposed Development Report approval. Geological terrain mapping work had been done almost at all states with coverage of 1,391km2. Selangor has the most mapped area with 466km2 coverage covering Putrajaya, Cheras, Kajang, Bangi and Sungai Buloh-Damansara area. JMG Kedah/Perlis/Pulau Pinang had mapped an area of 345km2 coverage of Pulau Jerjak and the whole of Pulau Pinang. Variety of derivative thematic maps from the geological terrain maping viz. Erosion Map, Landform Map, Physical Constraint Map and Construction Suitability Map had been produced for assessment and planning aid for development projects. A system of terrain mapping for land use planning was discussed by Chow and Zakaria (2002). Other activities include engineering geological investigations, slope stability studies and consultations. Consultations were given to local authorities and public on landslides, rock falls and sinkholes and monitoring for geohazard potential locations throughout the country. 2.6.2.2 Land Use Suitability for Development Review States that were requested to review land use suitability for developments are Selangor/Federal Territory Kuala Lumpur, Perak, Kedah/Perlis/Pulau Pinang and Negeri Sembilan/Melaka. JMG Kedah/Perlis/Pulau Pinang had been appointed as a panel reviewer for geotechnical reports under Committee of Hillside Planning and Development of Pulau Pinang, which was set up to review application for developments on hilly terrains. JMG Selangor/Wilayah Persekutuan had been appointed as a panel member in the Technical Committee for Development on Environmental Sensitive Area of Selangor and Committee for Hillside and Highland Area Development. 2.6.3 Local Government Department (Jabatan Kerajaan Tempatan – JKT) Any application for new development or building construction was made through local authorities such as the City Hall, Municipal Council, etc. All these authorities monitored by state government as well as the Ministry of Housing and Local Governments under the Local Government Department (Jabatan Kerajaan Tempatan – JKT). The authorities involved normally will ensure that the developers and their appointed professionals such Architects, Engineers, etc. should be responsible for any slopes constructed within their development area. This requirement basically laid out in the Uniform Building By-Law (UBBL) of the Street, Drainage and Building Act 1974 (Act 133). 2.6.4 Department of Environment (Jabatan Alam Sekitar – JAS) The involvement of Department of Environment (Jabatan Alam Sekitar – JAS) is due to the mandatory requirement to carry out Environmental Impact Assessment (EIA) for any development covering 50 hectares or more as stipulated in Environmental Quality Act 1974 (Act 127) Environmental Quality (Prescribed Activities) (Environmental Impact Assessment) Order, 38 Slope Safety System for Malaysia 1987. However, the vetting on the aspect of slope management is carried out with the assistance of JMG or JKR. 2.6.5 Town and Country Planning Department (Jabatan Perancang Bandar dan Desa – JPBD) The involvement of Town and Country Planning Department (Jabatan Perancang Bandar dan Desa - JPBD) in slope management is at the planning stage of any new development as stipulated in the Town and Country Planning Act 1976 (Act 172). The Act promotes integrated planning and management of land resources through proper use, conservation and development of lands. The JPBD of the Ministry of Housing and Local Government administers Act 172 that requires local planning authorities to prepare development plans (structure and local plans). However, the vetting process of slope management and possible geological hazards aspect in any Development Proposal Plan normally being carried out by JMG 2.6.6 Private Tolled Expressway Operator The main private tolled expressway operator in Malaysia, PLUS Expressway Berhad has engaged Opus International (M) Ltd. (formerly known as Pengurusan Lebuhraya Berhad) as the Project Management Consultant (PMC) for the more than 800 km long expressway. As a PMC, Opus has developed an in-house slope management system called the Expressway Slope Maintenance Management (ESMaS) which is part of Total Expressway Maintenance Management Network (TEMAN) (Madi, 2005, personal communication). The ESMaS is used to compile all slope information along the North South Expressway and other expressways operated by PLUS Expressway Berhad after slope inspection was carried out. These included the general information such as locations, type of slopes, latest date of inspections, etc as well as technical information such as the slope geometry, incipient sign of failures, etc. The ESMaS is also used to ranks the slope from very critical to not critical (Hussein, et al, 2004). Based on the slope ranking, Opus will recommend to PLUS on the status of the slope and its maintenance or remediation requirement. Opus with the assistance of Propel Bhd, the appointed maintenance contractor, also monitored all critical slopes during extreme raining season or when prolonged rainfall is observed in order to issue further warning or/and organize traffic management in the event of road closure due to landslide hazards. 39 Slope Safety System for Malaysia CHAPTER 3 3.1 RESPONSE TO LANDSLIDE EVENTS General Overview After disasters, there may be responses from the public, the press or the government. This chapter will discuss on the responses to landslide events between 1990 and 2004 by studying responses by the press and the government. The archives from press coverage of local newspapers as well other documentation and publications were used to establish the facts. 3.2 Press Response One of the sources of study on the response to the landslides is newspapers. Two newspapers were selected i.e. the New Straits Times, which was established since 1845 and The Star, which was established since 1971. These newspapers were selected due to the following: • The newspapers are the leading English language newspapers in Malaysia. • The English medium newspapers are read by middle class citizen and above where these group of citizen basically more critical towards any social and political issues. Daily issues of these papers were studied for two months after ten landslide events. Each newspaper has seven issues per week. Study on the newspapers archives were carried out at the Perpustakaan Tun Sri Lanang, the library of the National University of Malaysia (Universiti Kebangsaan Malaysia). The New Straits Times was stored as microfilms format (Plate 3.1) while The Star was stored as microfiches format (Plate 3.2). Plate 3.3 and 3.4 showed the equipment used for viewing the microfilms and microfiches respectively. Study was carried only on major landslide events occurred between 1990 and 2004 as presented in Chapter 2. Plate 3.1: The New Straits Times archives in form of microfilms 40 Slope Safety System for Malaysia Plate 3.2: The Star archives in form of microfiches Plate 3.3: Equipment (monitor) used for viewing microfilms 41 Slope Safety System for Malaysia Plate 3.4: Equipment (monitor) used for viewing microfiches 3.2.1 Objective of Study The objective of the study on the press responses is to record press coverage in a quantitative manner. 3.2.2 Method of Study The method of study used was a modification from one of established method in media research, Content Analysis. Stempell (2003) briefly explained the concept of Content Analysis. He stated, ‘Content Analysis is a formal system for doing something we all do informally rather frequently – draw conclusions from observations of content. We express opinions about the adequacy of various kinds of coverage by newspaper, magazines, radio stations, and television stations. Those opinions are based on what we observe as readers or listeners’. Wimmer & Dominick (1997) lay out in details on conducting research using Content Analysis. In order to quantify the newspaper cuttings, certain score value is assigned to different category of the newspaper cuttings based on size and location of the column (Figure 3.1). The score also reflects the importance of an individual article/column. For example, a headline article in the front page will be given the score value of 4 while a non-headline article in the front page will be given a score value of 3. The article with size more ¾ of total page will be assign with the score value of 4 while article with size of less than ¼ of total page is assigned with score value of 1. The total score of individual article/column will be obtained by multiplying the score value of the article size with the score value of the article location. For example, if the article is non-headline and located on front page (score value of 4) with the size of more than ¾ of total page (score value of 3), the total score value will be 12 (4 multiply 3). Along with the score data, note was also taken of the main comments and content of the press coverage (Table 3.1). Samples of article or column used from the selected newspaper are presented in Plate 3.5 to 3.8 42 Slope Safety System for Malaysia Column size Column size more than 3/4 page Column size between 1/2 and 3/4 page Column size between 1/4 and 1/2 page Column size less than 1/4 page Basically, the press coverage score value matrix chart can be used to any newspaper format as it was not based on absolute size but rather properties of a page. There are three common newspaper formats: i) the tabloid format with common size of 380mm x 300mm per spread, ii) Berliner format with common size of 470mm x 315mm per spread, and iii) broadsheet format with common size of 600mm x 380mm per spread (Wikipedia). The Star is a tabloid format while the New Straits Times was a broadsheet format. The New Straits Times has changed to tabloid format in 2005. Column location score 4 3 2 1 Frontpage (headline) 4 16 12 8 4 Frontpage (non-headline) 3 12 9 6 3 Inside (headline) 2 8 6 4 2 Inside (non-headline) 1 4 3 2 1 Editorial 25 Note on size of newspapers: The Star: Length = 380mm, Width = 300mm News Strait Times: Length = 600mm, Width = 380mm Figure 3.1: Chart of score value matrix for individual article/column in the newspaper. Note: i) the editorial column is directly designated with score value of 25 regardless of size and location ii) ‘headline’ denotes the main article on the page. 43 Slope Safety System for Malaysia Table 3.1: Summary of main comments and contents of press coverage Major landslide events (in Main comments/contents of press coverage chronological order) The collapse of Highland Towers (11 December 1993) Genting Sempah debris flow (30 June 1995) Gunung Tempurung slope failure (6 January 1996) Pos Dipang debris flow (30 August 1996) Paya Terubong rockslide (28 November 1998) Sandakan landslide (7 February 1999) Bukit Antarabangsa landslides (15 May 1999) Ruan Changkul landslide (28 January 2002) Taman Hillview landslide (20 November 2002) Bukit Lanjan rockslide (26 November 2003) 1) Special Cabinet Committee was set up at federal level 2) National Security Council was formed 3) Amendment of existing Uniform Building By-Laws of Street, Drainage & Building Act 1974 (Act 133) to ensure only qualified personal is employed and other requirements 4) Amendment of Town & Country Planning Act 1976 (Act 172) to set several guidelines for development of hillsides 1) Call to control private development on hillside 2) Guideline on Development on Hillside by Ministry of Housing and Local Governments 1) PLUS to construct new deviation of the 2km long expressway stretch 1) Formation of State Committee on Hillside Planning and Development by Penang State Government 1) Amendment to Guideline on Development on Hillside by Ministry of Housing and Local Governments 2) 2nd amendment to Town & Country Planning Act 1976 (Act 172) to allow local authorities to regulate hillside development 1) Formation of Cabinet Committee on Highlands and Islands Development in order to approve and monitor the proposed development on all Environmentally Sensitive Areas (ESA) 2) Formation of Technical Committee for Development on Environmentally Sensitive Areas (ESA) and Committee for Hillsides and Highlands Development by Selangor State Government 3) Guideline for the Development on Highlands by Ministry of Science, Technology and Environment 1) Formation of Slope Engineering Branch, JKR for managing road slopes and other slopes associated with the development of government project 2) Master plan for slope improvement measures in Malaysia 3) PLUS to enhance slope monitoring regimes 4) 6 months of road closure cause prolong massive traffic jams in KL and Klang Valley area 44 Slope Safety System for Malaysia Plate 3.5: Example of the full size headline article in the front page of The Star (not actual scale) Plate 3.6: Example of the headline article in the front page of the New Straits Times (not actual scale) 45 Slope Safety System for Malaysia Plate 3.7: Example of the full size headline article in the inside page of The Star (not actual scale) Plate 3.8: Example of the non-headline article in the inside page of the New Straits Times (not actual scale) 46 Slope Safety System for Malaysia Plate 3.9: Example of various sizes of article in the inside page of The Star (not actual scale) Plate 3.10: Example of the headline and other size articles in the inside page of the New Straits Times (not actual scale) 47 Slope Safety System for Malaysia 3.2.3 Results of Study The results of the study carried out on newspaper cuttings are presented in Figure 3.2 to 3.10 for each individual landslide event while Figure 3.11 and 3.12 presented the total days of coverage and the total press coverage score value against landslide fatalities. The collapse of Highland Towers recorded the highest press coverage score value as well as the most days of press coverage while Ruan Changkul landslide recorded the lowest score value as well as the fewest days of coverage by the press. Sandakan landslide has same days of coverage as Ruan Changkul landslide but with higher score value. The press coverage score value and days of coverage can be generally correlated with the numbers of fatalities (Figure 3.11 and 3.12). However, some events such as the Pos Dipang debris flow, Sandakan landslide and Ruan Changkul landslide, with many fatalities received little press coverage. Table 3.1 presented summary of main comments and contents of press coverage following each landslide event. Based on the newspaper’s content, observation can also be made on the Government actions following to each landslide event. Several major steps were taken by the Government following to the collapse of Highland Towers as well as the Taman Hillview landslide and the Bukit Lanjan rockslide. 3.2.4 Press Coverage Analysis Based on the trend of press coverage score value and numbers of days in press as presented in Figure 3.2 to 3.10, several factors can be considers to reflect the intensity of press coverage for any landslide event, such as the number of fatalities, the social status of those killed and the scale of economic/social impact. For example, the Pos Dipang debris flow (44 people died) received very much press coverage as compared to Genting Sempah debris flow (20 people died) and Ruan Changkul landslide (16 people died) received very much less press coverage as compared to Taman Hillview landslide (8 people died). This happened perhaps due to the events occurred far from the capital city of Kuala Lumpur and those killed were aboriginals’ people or immigrants. Overall, the analysis on press coverage showed the following: 1) Press coverage generally seems to increase with numbers of fatalities 2) Some landslide events with high numbers of fatalities have low press coverage score value. Three events involved aborigines and immigrants i.e. Pos Dipang debris flow, Sandakan landslide and Ruan Changkul landslide. 3) Some events have low numbers of fatalities but have moderate press coverage score value. Two events are Bukit Lanjan rockslide and Taman Hillview landslide. 48 Slope Safety System for Malaysia H i ghl a nd T owe r s C ol l a ps e 140 T he St ar 120 New St r ai t T i mes 100 80 Figure 3.2: Press coverage score value versus days for the collapse of Highland Towers 60 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days Ge nt i ng Se mpa h D e br i s Fl ow 140 120 T he St ar 100 New St r ai t T i mes 80 Figure 3.3: Press coverage score value versus days for Genting Sempah debris flow 60 40 20 0 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 Days G u n u n g T e mp u r u n g Sl o p e F a i l u r e 140 T he St ar 120 New St r ai t T i mes 100 80 Figure 3.4: Press coverage score value versus days for Gunung Tempurung slope failure 60 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days P os D i pang D ebr i s Fl ow 140 T he St ar 120 New St r ai t T i mes 100 80 60 Figure 3.5: Press coverage score value versus days for Pos Dipang debris flow 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days 49 Slope Safety System for Malaysia P a y a T e r u b o n g R o c k sl i d e 140 T he St ar 120 New St r ai t T i mes 100 80 60 Figure 3.6: Press coverage score value versus days for Paya Terubong rockslide 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days Sa nda k a n La nds l i de 140 T he St ar 120 News St r ai t T i mes 100 80 60 Figure 3.7: Press coverage score value versus days for Sandakan landslide 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days B uk i t A nt a r a ba ngs a La nds l i de 140 T he St ar 120 New St r ai t T i mes 100 80 Figure 3.8: Press coverage score value versus days for Bukit Antarabangsa landslide 60 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days R ua n C ha ngk ul La nds l i de 140 T he St ar 120 New St r ai t T i mes 100 80 60 Figure 3.9: Press coverage score value versus days for Ruan Changkul landslide 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days 50 Slope Safety System for Malaysia T a ma n H i l l v i e w L a n d s l i d e 140 120 T he St ar New St r ai t T i mes 100 80 60 Figure 3.10: Press coverage score value versus days for Taman Hillview landslide 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days B uk i t La nj a n R oc k s l i de 140 T he St ar 120 News St r ai t T i mes 100 80 60 Figure 3.11: Press coverage score value versus days for Bukit Lanjan rockslide 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Days Days of Press Coverage versus Landslide Events 45 40 48 New Straits Times The Star Press Coverage (Days) 35 20 30 25 8 44 20 1 0 15 10 0 0 17 16 5 0 1 2 3 4 5 6 7 Events (in chronological order) 8 9 Note on Events: 1 – Highland Towers 2 – Genting Sempah 3 – Gunung Tempurung 4 – Pos Dipang 5 – Paya Terubong 6 – Sandakan 7 – Bukit Antarabangsa 8 – Ruan Changkul 9 – Taman Hillview 10 - Bukit Lanjan 10 Figure 3.11: Days of press coverage versus landslides events. Note that numbers of top of bar represented death tolls. 51 Slope Safety System for Malaysia Total Press Coverage Score Value vs Fatalities 900 Total press coverage score value 800 The Star 1 New Straits Times 700 600 500 400 7, 3 10 5 300 Note on Events: 1 – Highland Towers 2 – Genting Sempah 3 – Gunung Tempurung 4 – Pos Dipang 5 – Paya Terubong 6 – Sandakan 7 – Bukit Antarabangsa 8 – Ruan Changkul 9 – Taman Hillview 10 - Bukit Lanjan 2 200 9 6 8 100 4 0 0 10 20 30 Fatalities (no) 40 50 60 Figure 3.12: Total press coverage score value versus fatalities. Note that the assigned numbers in the box represent the landslide events 3.3 Response from the Government The collapse of Highland Towers in 1993 provoked a strong reaction (Figure 3.11 and 3.12). A brief summary on some of the actions taken after is as follow (New Straits Times, 2003): • 12 days after the Highland Towers tragedy, Special Cabinet Committee was set up and chaired by Deputy Prime Minister. • The Special Cabinet Committee realized that more professionals need to be employed to strengthen local authority staff. All contractors’ supervisors and developers were made accountable for safety. • Amendment to existing Uniform Building By-Laws (UBBL) was made to ensure only qualified personal is employed. New UBBL required persons involved with construction to register under local authority where previously only engineers need to be registered. It also include requirement on proper and regular maintenance of slope is mandatory. • In the middle of 1996, Building Control Unit was established under Ministry of Housing and Local Government. The Unit was required to coordinate and draw up guidelines, plans and procedures as well as provide expert advice to local authorities on the safety and stability of building. The freeze on high rise buildings in hilly areas was lifted 6 months after mid 1996. The Government also decided that all new development projects should prepare complete report of development proposal with maps and plans that show the ground gradient and location of trees with more than 150mm in perimeter. Decision will be made based on the report. The Star (2002) reported that the Cabinet has agreed on the formation of Cabinet Committee on Highlands and Islands Development in order to approve and monitor the proposed development on all Environmental Sensitive Areas (ESA) in response to the Taman Hillview landslide in 2002. The Director General of Economic Planning Unit of Prime Minister Depatment in her keynote address (Raja Zainal Abidin, 2004) highlighted that in 2002, the Development Guidelines for 52 Slope Safety System for Malaysia Highlands was accepted and enforced by all State Governments in order to achieve sustainable development in highland areas. Following to the Bukit Lanjan rockslide in 2003, the Slope Engineering Branch (Cawangan Kejuruteraan Cerun) was officially set up in the JKR on 2 February 2004, primarily for managing road slopes and other slopes associated with the development of government projects. Raja Zainal Abidin (2004) also highlighted that another step forward taken by the government to address landslides was the initiation in 2004 of a study on the master plan for slope improvement measures in Malaysia. Appendix B presented the report by Minister of Works at UNESCAP meeting in Bangkok, Thailand. 3.3.1 Legal Frameworks of Actions and Improvement of Building Controls, Planning and Environmental Requirements Crisis and Disaster Management Unit of Division for National Security (1999) reported that some of the legislative and non-legislative for landslides reduction measures were: 1) Identification and mapping of landslides prone areas 2) Adaptation of land use regulation in landslip-prone areas 3) Development of design and building codes that will ensure the construction practices appropriate to the maintenance or enhancement of slope stability. 4) Amendment to Land Conservation Act (1960) to enable the Government to have a comprehensive monitoring of development activities of hill slopes. 5) Amendment to Environmental Impact Assessment (EIA) rules (1987). This is to enable Government to have closer monitoring and enforcement over development projects on hilly areas for the construction of roads, buildings and recreational facilities. The New Straits Times (2005) reported that there are four guidelines for the officers of Local Government Department involved in approving development project: 1) Development on hills 2) Planning for the conservation of the natural topography based on the Town and Country Planning Act 3) Development approval process, and 4) The approval process for building plans and Certificate for Occupancy through the One Stop Centre. The legal frameworks pertaining to slope management basically dealt with the planning stage as well as design and construction stage. However, there is no legal requirement on the postconstruction stage (maintenance). As such, maintenance of slopes always overlooked by most of the parties involved. 3.3.1.1 Planning Stage The Star (1993a) reported that the Minister of Science, Technology and Environment said one of technical group set up by the committee had recommended a need to review the Land Conservation Act 1960 (Act 385) which is an act relating to the conservation of hill land and the protection of soil from erosion and the inroad of silt and the National Land Code (1960). The technical group headed by Department of Environment also highlighted the need for all states to have land use master plans and residential development on hills to undergo Environmental Impact Assessments (EIA) under the Environmental Quality (Prescribed Activities) (Environmental Impact Assessment) Order, 1987 of Environmental Quality Act 1974 (Act 127), 53 Slope Safety System for Malaysia The Town and Country Planning Act (Amendment) 1995 passed after the collapse of Highland Towers in 1993 sets several guidelines for development of hillsides and land with specific geological features as reported by The Star (1997). These include preserving the original topography, no cutting and filling on slopes, preserving and planting trees and retained open spaces. The act also stipulates that no development be allowed on slopes exceeding 30o. Some of the directives or guidelines made were Jabatan Perancang Bandar dan Desa (1997 and 2000). In the planning stage, Section 22 of The Town and Country Planning Act 1976 (Act 172) as amended in 1995 and 2001 respectively has widened the statutory requirements in granting planning approval or Development Order (DO) (Gue & Tan, 2004). This section allows local authorities to regulate hill-site developments (defined as hill tops or hill slopes in the Act) by imposing a list of conditions to ensure sustainability, environmental friendly and of course public safety. The Act also states that planning approval may be subjected to certain conditions, namely the prohibition of damage to the land, natural topography and landscape, prohibition of the removal or alteration of any natural features of the land and the prohibition of the felling certain trees. Recently, the state of Selangor and Penang have imposed the requirements of a Geotechnical Report as well as an Independent Geotechnical Report submitted by separate engineers for areas which local authorities is of opinion that the proposed development site falls under the category of high risks. Chan (1998a) discussed some recommendations on effective management of hill land development in Penang. Section 70 of the Street, Drainage & Building Act (Act 133) 1974 (amendments 1994) also gives local authorities the power to impose additional condition (Gue & Tan, 2004). Under this Act, local authorities can give written directions to the person submitting a plan and specification in respect of compliance with ‘This or Other Act’ which would include compliance with the Town & Country Act, Land Conservation Act and Environmental Legislation. On the environmental aspects, the Environmental Quality Act 1974 gives the Minister the power to order and prescribe conditions on any activity which may have significant environmental impact. The following two prescribed activities under the Environmental Quality Act (Prescribed Activities) (EIA) Order 1987 are relevant to hill-site development (Gue & Tan, 2004): • Conversion of hill forest land to other land-use covering an area of 50 hectares or more (Paragraph 6; Forestry) • Hill station resort or hotel development covering an area of 50 hectares or more (Paragraph 17: Resort and Recreational Development) Environmental Impact Assessment (EIA) Report should be carried out according to prescribed guidelines, particularly in relation to assessment of the impact or likely impact of such development on the environment and proposed measures to prevent, reduce or control the adverse impact on the environment are being incorporated (534A of EQA). Ministry of Science, Technology and Environments (2002) send directive to all state governments on the latest guidelines of development on hill lands. Gue & Tan (2004) also mentioned that, in some states, the Land Conservation Act 1960 has been applied to prescribe certain areas as hill land by notification of gazette (Section 3). For example lands in Penang that are generally above 1,000 feet (300m) have been prescribed as hill land and therefore development is not allowed (Section 6). 3.3.1.2 Design and Development Stage Section 70 of the Street, Drainage & Building Act (Act 133) 1974 (amendments 1994) requires submission of infrastructures and building plans before construction is allowed (Gue & Tan, 54 Slope Safety System for Malaysia 2004). Earthwork precedes building construction and it is common practice to get infrastructure plans including earthwork be approved first while preparation for actual building plans are in progress. This allows the developer to reduce the holding time and save on cost. The earthwork plans should also include detailed mitigation plans to control the adverse impact on the environment especially erosion, siltation and additional runoff due to proposed site clearance. On the safety of earthworks or slope stability aspects, earthwork plans should clearly indicate the cut and fill slopes with the design slope gradients and surface and subsurface drainage details, retaining systems and strengthening measures such as soil nails, rock bolts and etc, if required. The design of slopes has to consider not only the safety of the slopes within the development site but also within the vicinity which may foresee ably affect the proposed building, if the slope fails. This ‘Duties at Common Law’ has been reaffirmed by the decision of the High Court and Court of Appeal in Highland Towers’ case. Duties of care to the neighbours in particular those located downslope such that their acts or omissions do not destabilize their neighbours’ properties. 3.3.2 Formation of National Security Council Subsequent to the Highland Towers tragedy, the Cabinet Ministers at a meeting on 18 May 1994 decided amongst others on the formation of an organization or mechanism to manage major land disasters and place it under the National Security Department (Bahagian Keselamatan Negara – BKN) of the Prime Minister Department (INSTEP, 2004). The organization is known as National Security Council (Majlis Keselamatan Negara – MKN). The directive of the formation, functions, terms of references, etc. pertaining to this Council is known as MKN 20. There are three levels of disaster management i.e. Level I (where can be simplified that basically manageable at district level), Level II (state level) and Level III (national level). Aini et al (2001) presented the evolution of emergency management in Malaysia in broader perspective. The mechanism will function at incident site to coordinate and execute all necessary action that has been taken in a major disaster by the existing rescue agencies including Special Malaysian Disaster Assistance and Rescue Team (SMART) to ensure all responses can be quick, efficient and effective. Disaster management cannot be depended upon any one particular agency or organisation but requires participation of multiple agencies with their own expertise and capability. In MKN 20, disaster defined as an incident that occurs suddenly, complex in nature and causes loss of lives, destruction of property or environment and disrupts the daily activity of local community. These include natural disasters like flood, landslides, etc. Previous landslides that have been declared as disaster in it own category includes the collapse of Highland Towers, Genting Sempah debris flow and Pos Dipang debris flow. 3.3.3 Formation of Slope Engineering Branch The Slope Engineering Branch (Cawangan Kejuruteraan Cerun) was formed on 2 February 2004. It is a new addition to the thirteen branches JKR have at the headquarters level and part of infrastructure sector. Brief introduction of this branch can be found in the website of JKR (www.jkr.gov.my/v2/english/ourServices/Infra_Cerun.asp). Two main goals that the Branch striving for are: • To reduce risks and fatalities from landslides • To effectively use the financial and manpower resources in slope repair and maintenance works 55 Slope Safety System for Malaysia The objectives of Slope Engineering Branch are: • To formulate proactive (not crisis-driven) slope safety and management policy • Develop slope safety and management system • Set criteria to define the levels ‘unacceptable’ and ‘broadly acceptable’ risks • Increase the safety standards for slopes • Increase public awareness on slope hazards The strategies of the Slope Engineering Branch that need to be employ in order to achieve its goals and objectives are: • Regulate and control hillside development • Design slope safety and management system based on risk management principles • Introduce new development control • Retrofit (install new elements or reinforced) and maintain existing slopes • Be alert or prepared for emergency all the time Based on the Annual Report of JKR 2004, the scope of works of Slope Engineering Branch were among others as follow: • Proposal of design for slope safety • Site survey • Ensure existing slopes are stable • Compliance with JKR specifications Among the early undertaken projects were: • Rebuilding drainage and retaining walls at Taman Hillview, Ampang, Selangor (due to landslide on 20/11/2002) • Slope inspection for project under Ampang Jaya Town Council (Majlis Perbandaran Ampang Jaya) in order to; i) to verify and summarise the preliminary geotechnical report from the slope safety perspective for the proposed projects, and ii) to formulate a recommendation from site inspection. 3.3.4 Initiatives by State Governments, other Government Agencies and Universities The establishment of Landslide Committee headed by Public Works Department and few other committees under the auspices of the Selangor State Government is aimed at facilitating National Natural Disaster Relief Committee to handle issue related to landslide and mudflow. Other committees initiated by Selangor State Government were Technical Committee for Development on Environmentally Sensitive Areas (ESA) and Committee for Hillsides and Highlands Development. The Penang State Government also has similar set up, Committee on Hillside Planning and Development to handle issues such as development on highlands as well as landslides. The State Government of Pahang, Sabah and Sarawak also have set up similar committee to handle hillside developments and landslides issues. Malaysian Centre of Remote Sensing (MACRES) has established National Disaster and Information Management (NADDI). NADDI objective is to establish central system for collecting, storing, processing, analyzing and disseminating value-added data and information to support relevant agencies in the mitigation and relief activities of disaster management in the country. Drainage and Irrigation Department (DID) or locally known as Jabatan Pengairan dan 56 Slope Safety System for Malaysia Saliran (JPS) under it’s Hydrology and Water Resources Division has also established Debris and Mudflow Warning System (DMWS) where their pilot project is for Cameron Highlands area. Several local universities initiated research centres related to landslide hazards in Malaysia such as the National Soil Erosion Research Centre (NASEC) by the University of Technology Mara (UiTM) and the Mountainous Terrain Development Research Centre (MTD-RC) by the Putra University of Malaysia (UPM) funded by the MTD Capital Berhad. 3.4 Response from Non-Governmental Organisations 3.4.1 Institution of Engineers Malaysia (IEM) Subsequent to the Bukit Antarabangsa landslide in May 1999, the Institution of Engineers Malaysia (IEM) formed a Position Paper Committee on Mitigating the Risk of Landslide on Hillsite Development. The position paper was submitted in July 2002 to the Ministry of Science and Technology and Ministry of Housing and Local Government. The position paper can be downloaded from the website of IEM, www.iem.org.my. The position paper proposed that the slopes for hill-site developments be classified into three classes and the necessary requirements i.e. Class 1 Development (Low Risk), Class 2 Development (Medium Risk) and Class 3 Development (Higher Risk). The IEM position paper also proposes that a new federal department called ‘Hill-Site Engineering Agency’ be formed under the Ministry of Housing and Local Government to assist local authorities in respect to hill-site development in order to regulate and approve all hill-site developments. The Agency could engage or outsource, whenever necessary, a panel of consultants to assist and expedite implementation. For existing hill-site development, the Agency should advise the local government to issue ‘Dangerous Hill-Side Order’ to owners of doubtful and unstable slopes so that proper remedial and maintenance works can be carried out to stabilize unstable slopes and prevent loss of lives and properties. The Institution of Engineers Malaysia (2000) also highlighted that issues pertaining to the risk of landslides on hill-site development in Malaysia are as follow: • Frequent occurrences of slope failure at hill-site in residential areas during the rainy season have resulted in public fear for the safety of lives and properties located in those areas. Lack of systematic regulatory measures to address the safety problems of hill-site development is the root cause of the problem. • Existing legislations and guidelines on slope failure mitigation have not been effective to produce a satisfactory solution • Lack of slope maintenance culture is prevalent in both public as well as private sector The Star (1993b) reported that the IEM in conjunction with the Association of Consulting Engineers Malaysia (ACEM) has prepared a proposal for greater regulation in the industry and regular inspection of building and surrounding areas in order to make the building industry safer for submission to the Cabinet. The proposal suggests having a register for all consultants, contractors and supervisors in the industry. The proposal also called for an engineer’s report to be made available on the purchase of any building. The Board of Engineers Malaysia (BEM) later introduced Registration of Accredited Checker (AC) for structural and geotechnical works. The registration is under Section 10B of the Registration of Accredited Checker, Registration of Engineers Act 1967 (Revised 2002). 57 Slope Safety System for Malaysia 3.4.2 Environmental Non-Government Organisations The environmental non-government organizations (NGOs) made several initiatives in order to push the government to have better policy, regulations and controls over hill-site development leading to proper slope management initiative. The Malaysian Hills Network, a coalition of four major conservation groups in the country, insisted government to draw up a comprehensive policy on sustainable development of hills and highlands (The Star, 1996b). The network comprises of Friends of the Earth, Malaysia (Sahabat Alam Malaysia – SAM), World Wildlife Fund (WWF), Malaysian Nature Society (MNS) and Consumer Association of Penang (CAP). The biggest initiative is the formation of a “virtual federation/association” of eighteen different NGOs namely, the Malaysian Environmental NGOs (MENGO) in 2002. MENGO united by a common concern about the environment and environmental issues with the common goals among others are to increase environmental awareness in the Malaysian society and to encourage and develop policies to support sustainable development. Brief introduction of MENGO can be assessed through it website, www.mengo.org. Even though MENGO activities and initiatives cover bigger aspect of environmental issues, landslides and slope management will always part of it main concern. Some of MENGO projects include workshop on ‘Highland Development and Environmental Considerations: Implication for Media’, Series of dialogue with local governments and relevant authorities such as for the review of State Development Plan, Local Agenda 21, etc. MENGO contribution is highlighted in the Ninth Malaysia Plan 2006-2010 (Economic Planning Unit, 2006). 58 Slope Safety System for Malaysia CHAPTER 4 4.1 A NATIONAL SLOPE SAFETY SYSTEM General Overview Malone (2003) argued that once a community has decided to take action to reduce landslide losses, there is logical sequence to follow. We cannot design a Slope Safety System until goals have been defined and goals cannot be defined until we have failure data and rainfall data in the case of rainfall-induced landslides. Having decided the goal, the design of a Slope Safety System to achieve the goal can proceed. The Slope Safety System involves set of actions (Malone, 2003). Engineering works, policing actions, town and country planning, education, research are among the action needed. Some actions are quicker-acting and more cost effective than others (Malone, 1997a): a balanced design is needed. We need to know the size of the problem. We need to know the trends. Are losses increasing annually, in line with population growth, economic activity, traffic increase? In the case of rainfall-induced landslides, losses will depend on rainfall patterns and intensities. We will need good past rainfall data. The design of a National Slope Safety System (NSSS) for Malaysia should be related to findings in Chapter 1 to 3. There has been significant response to landslide events, both from the press and the government. The landslide events that triggered the biggest press response are those with: • Many loss of lives i.e. more than 10 lives • Closure of expressway mainly North South Expressway for several weeks to months. Based on findings in previous chapters, there are responses by Federal Government as well as State Government. Some of the Federal Government responses are as follow: • Private development control after the collapse of Highland Towers • The formation of JKR Slope Engineering Branch after the Bukit Lanjan rockslide Some of the State Government responses are as follow: • Selangor State Government has established the Landslide Committee headed by Public Works Department, Technical Committee for Development on Environmentally Sensitive Areas (ESA) and Committee for Hillsides and Highlands Development to handle issues related to landslides and hillside developments • The Penang State Government also has similar set up, Committee on Hillside Planning and Development to handle issues such as development on highlands as well as landslides. • The State Government of Pahang, Sabah and Sarawak also have set up similar committee to handle hillside developments and landslides issues. The design of a National Slope Safety System also needs a quantitative goal expressed as loss reduction aim to meet the needs of: public, local government, state government and federal government. It should reduce losses (life, road closure, etc) and be seen to do so. The framework of a National Slope Safety System should also in line with Disaster Management Plan developed by Crisis and Disaster Management Unit, Division for National Security, Prime Minister’s Department. The evolution of the plan is presented in Crisis and Disaster Management Unit (1998, 1999, 2003 and 2005). Malone (2003) stressed that a community must decide for itself how far it wishes to go in a National Slope Safety System. But the law of diminishing returns applies – so not even the richest community can ever reduce losses to zero. The community must 59 Slope Safety System for Malaysia adopt realistic goal well short of zero losses. Deciding on such a goal is not an easy matter, but there are some rational approaches. Appendix C presented discussions on vulnerability and risks management of landslide hazards by some renowned world experts. 4.2 Baseline Record Based on findings in previous chapters, major consequences of the landslide hazards in Malaysia are as follow: 1) Significant fatalities in developed/residential areas, and 2) Prolonged roads closure especially the expressway, major highway, etc. For fatalities, there are a total of 186 known fatalities for a period of 14 years between 1990 and 2004, which means that an average of 13 people died per year or approximately 1 person died every month due to landslides. For road closures, a total of 218 days for a period of 14 years between 1990 and 2004 are known, which means that an average of 15.6 days of road closure per year or 1.3 days of road closure per month due to landslides. The above information illustrates the approach. Much further data exists and should be compiled and analysed quantitatively to create a quantified baseline record for losses in Malaysia. The baseline record is then used to help set the loss reduction goal of a National Slope Safety System. 4.3 Loss Reduction Goals For estimation, let’s take that a goal for a National Slope Safety System for Malaysia is to reduce annual losses (fatalities and road closure) by 30% within 5 years time, between 2006 and 2010, in line with the 5 year Malaysian Plan (Note: 9th Malaysian Plan for 2006 to 2010 was launch by the Prime Minister in mid-2006). By the year 2010, the numbers of fatalities due to landslide hazards would be reduce to 9 persons per year or 1 person per 2 months. At the same time, the road closure would also be reduced to 10.9 days per year or 0.9 day per month. 4.4 Loss Reduction Plan The common components of a Slope Safety System have been established as presented in Table 4.1 (Malone, 1997a and 1997b). The important components are: • Policing (control of new slopes, etc) • Safety standards and research • Works projects (retrofitting, routine maintenance, etc) • Education and information The steps and action plans in setting up a National Slope Safety System as presented in Table 4.2 (Malone, 1999a and 1999b) will be very much easier with consideration that the Government of Malaysia already appointed the Safety Manager of the system, the Slope Engineering Branch of the Public Works Department. Various legislations, laws, regulations, guidelines, etc. on hillside developments, slopes design and slopes construction at various government levels have been developed since the collapse of Highland Towers. Strict enforcement, follow up actions as well as regular improvement on 60 Slope Safety System for Malaysia existing laws, regulations, etc together with additional manpower (professionals or/and trained personnel) is required and needed to properly enforce and implement a successful Loss Reduction Plan. Table 4.1: The Components of Slope Safety System (after Malone, 1997b) Contribution by each component Slope Safety System components to reduce landslide risk to address public Hazard Vulnerability attitudes Policing Cataloging and safety screening and statutory repair orders Checking new works Maintenance audit Inspecting squatter areas and recommending safety clearance / / / / / Safety standards and research / Works projects Upgrading old government slopes Preventive works for old tunnels / / / Education and information Maintenance campaign Personal precautions campaign Awareness programme Information services Landslip warning and emergency services Input to land use planning / / / / / / / / / / / / / / / Table 4.2: Route map of setting-up of slope safety system (modified after Malone, 1999b) Steps Activity 1 Appoint Safety Manager 2 Start research unit 3 Make policy submission and preliminary resource bid 4 Carry out system design 5 Make detailed resource bid 6 Receive mandate 7 Commence emergency preparedness actions and public education programme 8 Begin relocation of squatter at hill slope (if any) 9 Start data acquisition and annual reviews of system 10 Enhance control of new slope works 11 Provide public information service on hazards 12 Start remedial works and retrofit Crisis and Disaster Management Unit (2003) stated that the strategy and recommendations made are to improved inter-agency and inter-stakeholder collaboration on environmental management, development planning and biodiversity conservation of the highlands, so as to ensure sustainable economic development. There are two recommendations that directly involved slope safety namely recommendation no. 5 and 6 respectively. The details of the recommendations as follow: 61 Slope Safety System for Malaysia Recommendation No. 5: A systematic slope maintenance programme should be undertaken with emphasis on early detection and prevention of slope instability problems • Based on regular inspection and monitoring slopes, government agencies and private property owners and occupants should formulate and implement slope maintenance programme to carry out preventive maintenance of slopes. This is especially important for slopes which pose risk to the public, such as slopes along main roads and slopes adjacent to densely populated areas. Its is recommended that the local authorities and Public Works Department (JKR) undertake a systematic slope maintenance programme and that include: • Establishment of a database of slope characteristics • Identification and mapping of critical slopes • Regular inspection of all slopes • Establishment of a physical monitoring programme of all critical slopes • A system to disseminate information on slopes to relevant stakeholders including the local community. Recommendation No. 6: Occupants and property owners should be educated on ways to monitor slopes within their property. • Local authorities should educate occupants and property owners on the importance of regularly monitoring slopes within their properties. Example may be drawn from Hong Kong, where Civil Engineering Development Department provides information to the public on ways to inspect slopes and walls within private property. • Property owner should be given guides on early detection of potential slopes problems and how to recognize the warning signs of potential slopes failures. • The public will then be able to assist the authority in monitoring slopes on a wider scale. The public can further motivated for being informed on the catastrophe that could befall them should any major slope failure occurs. • The Public Works Department (JKR) could assist by providing technical advice to the local authorities. 4.5 Budget for a National Slope Safety System The budget required should be estimated. The Malaysian Government 2006 Budget presented by the Minister of Finance in the parliament on 1st September 2006 estimated a total expenditure of RM136,748,522,510 for the following year where 74% of it is an operating expenses while 26% is development expenses (Treasury Malaysia, 2006). By comparison with Hong Kong, where expenditure on the Slope Safety System is about 0.7% of Government expenditure, the National Slope Safety System for Malaysia might require an annual operating expenditure of approximately 0.5% of total public expenditure for the country i.e. say RM700 millions. It should be appreciated that the commitment will have to be long-term. After 30 years of work, Hong Kong still has not completed the job of making safe the dangerous old slopes built in the economic boom years of the 1950s to 1970s when there was no effective control on new slope works. As effective controls have yet to be introduced in Malaysia presumably new dangerous slopes are still being built. 62 Slope Safety System for Malaysia 4.6 Implementation of a National Slope Safety System Based on political situation and administration system in Malaysia, the implementation of a National Slope Safety System required commitment and cooperation various parties, stakeholders and government agencies at various level. The partnerships concept and model proposed by the United States Geological Survey (USGS) as presented in Spiker & Gori (2003) and reviewed by the Committee on the Review of the National Landslide Hazards Mitigation Strategy (2004) is suitable for application in Malaysia with some modification. There are five focal points for partnerships as highlighted by the Committee that will inevitable entail relationship within and among multiple levels of government and with non-governmental entities: 1) Partnerships between the federal agencies involved in landslide mitigation to provide leadership and national coordination 2) Partnerships between federal agencies and their state counterparts to promote hazard mapping and risk analysis at the state level 3) Partnerships between state agencies and local governments, non-governmental groups and private citizens to ensure that education and assistance is provided to the “frontline” of mitigation activities. 4) Research partnerships between federal agencies and academic institutions in collaboration with state, local and non-governmental partners to conduct research on landslide process mechanics, monitoring techniques, loss and risk assessment methods and mapping techniques 5) International partnerships for global exchange of knowledge and technique. The improvement of the implementation of the National Slope Safety System is needed to be monitored every year. 63 Slope Safety System for Malaysia CHAPTER 5 CONCLUSION The study has briefly reviewed the landslide history in Malaysia between 1990 and 2004 and highlight some of major landslide events occurred within that period. The historical archives of landslide events are very important to record the pattern, trend, consequences and other relationships in order to understand the landslides and ways to prevent or mitigate it. The responses toward landslide events especially from the press as well as the government were also recorded. This is also important in order to understand the development of steps or actions taken toward improving the risk of landslide hazards. The main objective of this study is to recommend a National Slope Safety System for Malaysia. The study also highlight the important of understanding and developing Slope Safety System based on risk management principles. A concept on a National Slope Safety System is presented and it was proven effective in many aspects included human resources, financial, etc. It is timely for the Government of Malaysian to introduce and implement such system. The cooperation among various stakeholders is the key point for a successful implementation of Slope Safety System in a multi level governance system such as in Malaysia. It is important to note that the landsliding problems are more than scientific, engineering, technological or economic problems. It needs multidisciplinary approaches with the involvement of various levels of stakeholders and relevant parties. It is indeed a political problem (Malone, 2006, personal communication) to be undertaken seriously by the Government as it require political will to seriously mitigate the problems. 5.1 Recommendations for Further Study Some of the recommendations for further study are as follow: 1) Thorough study is required to get more representative results throughout the landslides history of Malaysia. Study presented in this dissertation may become a basis for further study. More data is required to see the trends, patterns and other relationships 2) It is a known fact that most of landslides occurred in tropical and subtropical region are very much related to rainfall. Therefore, good rainfall data are crucial for further study as the consistent data on landslide-rainfall relationship in Malaysia is almost not available. 3) It is important to gather and compile all the findings and investigation results carried out on significant landslides in Malaysia. Some of the reports unfortunately were not published. 4) Further study should also focus on how to improve cooperation among all the stakeholders such as federal, state, local, etc and on how to improve research and development with regards to landslide hazards which require multi disciplinary approach. Further study also needed in the area on how to improve training, education as well as public awareness on landslide hazards. 64 Slope Safety System for Malaysia REFERENCES Aini M. S. et al, 2001, Country report: Evolution of emergency management in Malaysia, Journal of Contingencies and Crisis Management, Vol. 9, No. 1, Blackwell Publishers. Central Bank of Malaysia (Bank Negara Malaysia), 2005, Annual Report ’05. Chan, N. W., 1998a, Environmental hazards associated with hill land development in Penang Island, Malaysia: some recommendations of effective management, Disaster Prevention and Management, Vol. 7, No. 4, MCB University Press, pp 305 – 318. Chan, N. 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Malaysian Meteorological Department, Rainfall Distibution, [available www.kjc.gov.my/english/education/climate/climate01.html assessed on 9/6/2006] at Malone, A. W., 1997a, Managing slope safety in a high density city prone to landslips, Proceedings of the Hong Kong Institution of Engineers Safety Conference 1997, HKIE, pp 21-29. Malone, A. W. 1997b, Risk Management and Slope Safety in Hong Kong, Transactions of the Hong Kong Institution of Engineers, Vol 4, No. 2 & 3, pp 12-21. republished in Li, K. S., Kay, J. N. & Ho, K. K. S. (eds), 1998, Slope Engineering in Hong Kong, A. A. Balkema, Rotterdam, pp 3-17. 67 Slope Safety System for Malaysia Malone, A. W., 1999a, Guidance on setting up a slope safety system designed on risk management principles, Proceedings of 19th Annual Seminar, Geotechnical Risk Management, Geotechnical Division, HKIE, pp 97-103. Malone, A. W., 1999b, Slope safety systems for Asian cities, keynote lecture, Proceedings of 2nd International Conference on Landslides, Slope Stability and the Safety of Infrastructures, Singapore Malone, A. W., 2003, What data do we need for slope safety management purposes?, Presentation to the Seminar Pengurusan Cerun 8 May 2003, TSR Project Slope Protection Study for Federal Route 22 Tamparuli – Sandakan Road, Sabah Malone, A. W., 2006, Discussion on Slope Safety System (personal communication). Ministry of Finance, 2005, Economic Report 2005/2006, Volume 34, Percetakan Nasional Malaysia Berhad. Ministry of Science, Technology and Environments, 2002, Garis Panduan Pembangunan di Kawasan Tanah Tinggi [via letter with ref: KSTAS (S) 210.020.P006/001 dated 22 June 2002]. Nik Hassan, N., R., 1995, Geotechnical engineering investigations of the Highland Tower Condominium collapse, Ulu Kelang, Selangor, Warta Geologi, Vol. 21, No. 3, pp 153-162 Othman, M. A., 1996, Debris flow at the Tunnel bypass road from Kuala Lumpur-Karak Highway to Genting Highlands, Technical Bulletin November 1996 (PP 9528/9/96), Road Engineering Association of Asia and Australasia (Malaysian Chapter) Othman, M. A., Azman, A. S., Mat-Barhan, H. & Norman, M. Y., 1994, Some Thoughts on the Collapse of the Highland Tower, Hulu Kelang, Selangor, West Malaysia, Proceeding Forum on Geology & Hillside Development, 22/7/1994, Geological Society of Malaysia, University of Malaya, Kuala Lumpur. Population Division of the Department of Economics and Social Affairs of the United Nations Secretariat, 2005a, World Urbanisation Prospects: The 2004 Revision, Urban and Rural Areas Dataset (POP/DB/WUP/Rev.2003/Table A.7) dataset in digital form [available at http://earthtrends.wri.org assessed on 20/6/2006] Population Division of the Department of Economics and Social Affairs of the United Nations Secretariat, 2005b, World Population Prospects: The 2004 Revision, Dataset on CD-Rom, New York [available at http://earthtrends.wri.org assessed on 22/6/2006] Raj, J. K., 2000, Rainfall and Slope Failures in the Granitic Bedrock Areas of Peninsular Malaysia, Proceedings of the Annual Geological Conference 2000, 8-9 September, Geological Society of Malaysia, pp 275-282 Raja Zainal Abidin, R. Z., 2004, IWRM Implementation Realities in Malaysia, Keynote Address, Malaysia Water Forum, 8-10 June 2004, Kuala Lumpur. Spiker, E. C. & Gori, P. L., 2003, National Landslide Hazards Mitigation Strategy: A Framework for Loss Reduction, Circular 1244, U.S. Geological Survey, Virginia, USA, pp 56. 68 Slope Safety System for Malaysia Stempel, G. H., 2003, Content Analysis, Stempel, G. H., Weaver, D. H. & Wilhoit G. C. (Eds), Mass Communication Research and Theory, A&B Press, New York, USA. The Borneo Post, 1999, 8 February, 17 killed in landslip The News Strait Times, 2003, 28 November, A look at previous major landslides. The News Strait Times, 2005, 26 April, Ong: Stick to the guidelines The Star, 1993a, 17 December, Review of laws to control hill projects The Star, 1993b, 19 December, Register for building industry The Star, 1996a, 7 January, Landslides over the past six months The Star, 1996b, 9 February, Group wants policy on hills. The Star, 1997, 22 July, Reaching its peak The Star, 2002, 25 November, Committee formed Treasury Malaysia, 2006, Budget 2007, Ministry of Finance [available http://www1.treasury.gov.my/index.php?ch=12&lang=eng assessed on 5/9/2006] at Turner, A. K. & Schuster, R. L. (Eds), 1996, Landslides Investigation and Mitigation, Special Report 247, Transportation Research Board, National Research Council, National Academy Press, Washington D. C., USA., 675 pgs. Utusan Malaysia, 2004, 12 October, Kejadian tanah runtuh di lebuhraya sejak tahun 1993 (in Bahasa) Utusan Malaysia, 2005, 25 February, Sistem RM160 juta kesan tanah runtuh (in Bahasa) Utusan Malaysia, 2005, 19 July, Pembangunan syarat baru kepada pemaju (in Bahasa). Wikipedia, Newspaper [available at http://en.wikipedia.org/wiki/Newspaper assessed on 10/6/2006] Wimmer, R. D. & Dominick, J. R., 1997, Mass Media Research – An Introduction, 5th Edition, Wadsworth Publishing Company, New York, USA., pgs 492. 69 Slope Safety System for Malaysia APPENDIX A The World Bank and United Nations Statistics According to Development Data Group, The World Bank (2005), Gross Domestic Product (GDP) Annual Growth Rate is the change in the total annual output of a country’s economy in constant prices from one year to the next. GDP is the total market value of all final goods and services produced in the country in a given year, equal to total consumer, investment and government spending. The data used average annual compound growth rates calculated from constant price data in local currency and published by Development Data Group, The World Bank (2005). The World Bank publishes the World Development Indicators each April and the values available from 1960 to 2004. GDP value generally is used to indicate the economic growth of the country. Urban population refers to the midyear population of areas defined as urban (Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat, 2005a). Any person not residing in an area classified as urban is counted in the rural population. Definitions of urban populations vary slightly from country to country. The dataset provided by United Nations contained estimates from 1950 to 2000 in five years intervals. For 2001 to 2030, all data are forecasts based on assumptions made using established method. The United Nation Population division (UNPD) updates the information every two years. Total Population refers to the de facto midyear population in the country as of July 1 of the year indicated (Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat, 2005b). The projections reported here assume medium fertility (the “medium-fertility assumption” of the UNPD). The dataset contains estimates for all years from 1950 to 2005. For 2006 to 2050, all data are forecasts based on assumptions used. The UNDP updates the information every two years and the most recent data are from the 2004 revision. References Development Data Group, The World Bank, 2005, World Development Indicators 2005 online [available at http://earthtrends.wri.org assessed on 20/6/2006] Population Division of the Department of Economics and Social Affairs of the United Nations Secretariat, 2005a, World Urbanisation Prospects: The 2004 Revision, Urban and Rural Areas Dataset (POP/DB/WUP/Rev.2003/Table A.7) dataset in digital form [available at http://earthtrends.wri.org assessed on 20/6/2006] Population Division of the Department of Economics and Social Affairs of the United Nations Secretariat, 2005b, World Population Prospects: The 2004 Revision, Dataset on CD-Rom, New York [available at http://earthtrends.wri.org assessed on 22/6/2006] I Slope Safety System for Malaysia APPENDIX B Report by Minister of Works at UNESCAP Meeting Bernama (2005) reported that the Minister of Works has presented a report on the actions taken by government on slope management and Malaysia's experience in handling restoration of road infrastructures in the wake of natural disasters at a meeting hosted by the United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) chaired by him in Bangkok, Thailand. The steps will serve as preventive and precautionary measures. It’s highlighted that the Public Works Ministry has adopted a 12-point action plan to prevent landslides along expressways and for monitoring and investigation of slopes using helicopters and on foot. The creation of a Research and Development Department at the Malaysia Highway Authority (Lembaga Lebuhraya Malaysia - LLM) headquarters would identify and study the best methods and latest technology on geotechnical. He said other measures include: • Inspecting and monitoring programmes in detail and engage more technical expertise • Preparing complete reports on physical status of slopes along highways, especially the critical ones, using Slope Management System • Implementing catalogue system by giving identification for all slopes along highways • Marking slope locations on the highway map using slope numbers on it • Installing Early Warning System by setting up "rain gauge" to measure rainfall and earth movements with real-time frames • Investigating the best method of slope treatment • Creating awareness on the importance of slope management to the public, especially to residents at risk nearby • Re-evaluating and improving emergency respond time • Establishing a comprehensive slope management system; and • Focusing and improving on slope landscaping, especially on safety and aesthetic value. Following the rockslide incident in Bukit Lanjan at Km21.8 of the North-South Expressway in November 2003, the Concessionaire Company - PLUS Expressways Berhad - had enhanced the slope monitoring regimes undertaken at the selected critical locations. The identified six critical slope areas which require close monitoring regimes are Bukit Merah, Jelapang, Post Kuala Dipang, Gua Tempurung, Bukit Lanjan and Ma'Okil. Activities that have been carried out to-date include increased on-foot slope inspection frequencies on a two-month cycle for all critical slopes, in addition to the normal periodic inspection which was carried out either on four months or six months cycle. Other activities carried our were Heli-ride/Aerial Surveillance Assessment where in addition to the monthly general aerial surveillance, technical aerial inspections for the critical slope areas on every two to four month interval basis have been carried out to mitigate any potential threat to the expressway and also to capture the general conditions of slopes or detect any sign of distress and erosion. PLUS will conduct Slopes Instrumentation Monitoring which included the installation of slopes instrumentation for the selected critical slopes have been completed to monitor the rainfall intensity, ground water level and slope movements. The results of the monitoring values would be used for determining the trigger values for preventive measure purposes. PLUS will also undertook Water Catchments Study where desk study and on-foot inspections on the large water catchments and critical slope areas that might have potential threat to the expressway have been carried out to identify areas of potential debris flow outside PLUS Right of Way. The area for the catchments study that have been identified are classified into six sectors namely Bukit Merah Interchange (Km194-Km195), Jelapang (from Km257 to Km265), Gua Tempurung (from Km301-Km305), Post Kuala Dipang (from Km310 to Km313), Bukit I Slope Safety System for Malaysia Lanjan Interchange (from Km22 to Km24) and Ma'Okil (from Km120 to Km139). Another activity carried out by PLUS was Structural Geology Mapping of Selected Rock Slopes. The geological mapping of the selected rock slope areas have been carried out to reassess the condition of the slope and determine any immediate remedial and preventive works required. In other occasion, Utusan Malaysia (2005) reported that all federal roads and major highways with high potential of landslides will be equipped with slope monitoring system as said by the Minister of Works. The system will be implemented as soon as the Ministry of Works received the budget of RM160 millions granted from Federal Government and will be operated by JKR. LLM will create monitoring centre at all slopes on highways with high landsliding potential. For private expressway, the Concessionaire Company will bear the cost themselves. The slope monitoring system will ensure that any landslides information will be disseminate fast enough through intelligent information system with LLM. Slope monitoring will be carried out in JKR headquarters and all information will be send through satellite and GSM as well as optical fibre network installed at selected locations. References Bernama, 2005, 13 June, 12-point plan to prevent landslides along highway, Eye on UNESCAP, Issue No. 031, 13/6/2005, United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) [available at www.unescap.org assessed on 20/1/2006] Utusan Malaysia, 2005, 25 February, Sistem RM160 juta kesan tanah runtuh (in Bahasa) II Slope Safety System for Malaysia APPENDIX C Vulnerability and Risks Management of Landslide Hazards According to the Committee on the Review of the National Landslide Hazards Mitigation Strategy (2004), the socioeconomic effects from the landslides that occur each year impact people, their homes and possessions; industrial establishments; and transportation, energy and communication lifelines (e.g. highways, railways, communications cables). The socioeconomic losses are increasing as the pressure of expanding populations causes the built environment to expand into more unstable hillside areas. Landslides are responsible for considerably greater economic losses and human casualties than is generally recognized – although they represent a significant element of many major disasters, the magnitude of their effects is often overlooked by the news media. Landslide costs include both direct and indirect losses affecting private and public properties. Direct costs can be defined as the costs of replacement, rebuilding, repair or maintenance resulting from direct landslide-caused damage and destruction of property or installations. Public costs are those borne by government agencies – national, regional or local. All other costs of landslides are indirect, for example: • Reduced real estate values in area threatened by landslides • Loss of tax revenues on properties devalued as a result of landslides • Loss of industrial, agricultural and forest productivity and of tourist revenues as a result of damage to land or facilities or interruption of transportation systems • Loss of human or domestic animal productivity because of death, injury or psychological trauma • Costs of measures to prevent or mitigate potential landslide activity The Committee on the Review of the National Landslide Hazards Mitigation Strategy (2004) also stated that an understanding of the economic and societal impacts of landslides is essential for informed decisions that address the risks from landslides and other ground failure hazards. Documentation of injuries and deaths, property damage, economic disruption, relief and repair costs and environmental consequences is part of such an understanding. Undertaking risk assessments of prospective losses for failure-prone areas is an allied and equally important process. Loss and risk assessments are essential for: • Establishing a sound rationale for risk reduction programmes based on documented economic and societal impacts • Evaluating the cost-effectiveness of proposed interventions for landslide-prones areas • Creating mechanisms for risk sharing involving the public and private sectors through insurance, special assessment districts or other financial risk pooling • Partitioning responsibility for landslide-related clean up, repair and rehabilitation costs • Understanding the non-economic consequences of landslides events especially to the environment. United Nations Development Programme (2004) stated that the economic losses or impact of disaster (landslides) are conventionally categorized as: • Direct cost – physical damage, including that to productive capital and stocks (industrial plants, etc.), economic infrastructure (roads, etc.) and social infrastructures (homes, schools, etc.) • Indirect cost – downstream disruption of the flow of goods and services, e.g.: lower output from damaged or destroyed assets and infrastructure and the loss of earnings as 1 Slope Safety System for Malaysia • income-generating opportunities are disrupted. Indirect cost also includes the cost of medical expenses and lost productivity arising from the incidents. Secondary effects – short and long term impacts of a disaster on the overall economy and socio-economic conditions such as fiscal and monetary performance, levels of household and national indebtedness, etc. Figure A1 presented the hypothetical diagram to show the contemporary magnitude-frequency distribution of landslides divided into non-cost-inducing events, cost-inducing hazards and disasters and the postulated relationships with average and total costs of impact (Lee & Jones, 2004) while Figure A2 presented the diagrammatic representation to show how risk is the product of hazard and vulnerability (Coburn & Spencer, 1992 in Lee & Jones. 2004). Figure A1: Hypothetical diagram to show the contemporary magnitude-frequency distribution of landslides divided into noncost-inducing events, costinducing hazards and disasters and the postulated relationships with average and total costs of impact (after Lee & Jones, 2004) Figure A2: diagrammatic representation to show how risk is the product of hazard and vulnerability (after Lee & Jones, 2004 based on Coburn & Spencer, 1992) 2 Slope Safety System for Malaysia United Nations Development Programme (2004) stated that the destruction of infrastructure and the erosion of livelihoods are direct outcomes of disaster but disaster (such as landslide) losses interact with and can also aggravate other financial, political, health and environmental shocks. Such disaster losses may setback social investments aiming to ameliorate poverty and hunger, provide access to education, health services, safe housing, drinking water and sanitation, or to protect the environment as well as the economic investments that provide employment and income. United Nations Development Programme (2004) also recommended six emerging agendas within disaster risk reduction comprises of the following: 1) Appropriate governance is fundamental if risk considerations are to be factored into development planning and if existing risks are to be successfully mitigated. Development needs to be regulated in terms of its impact on disaster risk. Perhaps the greatest challenges for mainstreaming disaster risk into development planning are political will and geographical equity. These are problems shared through environmental management and environmental impact assessment. How to attribute responsibility for disaster risk experienced in one location that has been caused by actions in another location? 2) Factoring risk into disaster recovery and reconstruction. Development appraisal and decision making tools, and monitoring programmes that incorporate disaster risk management are needed to mainstream prospective disaster risk management. 3) Managing the multifaceted nature of risk. Natural hazard is one among many potential threats to life and livehood. Often those people and communities most vulnerable to natural hazards are also vulnerable to other sources of hazard. 4) Integrated climate risk management. Building on capacities that deal with existing disaster risk is an effective way to generate capacity to deal with future climate change risk. 5) Compensatory risk management. In addition to reworking the disaster-development relationship, a legacy of risk accumulation exists today and there is a need to improve disaster preparedness and response 6) Addressing gaps in knowledge for disaster risk assessment. A first step towards more concerted and coordinated global action on disaster risk reduction must be a clear understanding of the depth and extent of hazard, vulnerability and disaster loss. United Nations Development Programme (2004) stated that natural disaster risk is intimately connected to processes of human development. Disasters put development at risk. At the same time, the development choices made by individuals. Communities and nations can generate new disaster risk. But this not being the case as human development can also contribute to a serious reduction in disaster risk. There are many examples of the drive for economic growth and social improvement generating new disaster risks such as landslides. Rapid urbanization is an example. The growth of informal settlements and inner city slums, whether fuelled by international migration or internal migration from smaller urban settlements or the countryside, has led to the growth of unstable living environments. These settlements are often located in ravines, on steep slopes, along flood plains or adjacent to noxious or dangerous industrial or transport facilities. United Nations Development Programme (2004) also stated that bringing disaster risk reduction and development concerns closer together requires three steps: 1) The collection of basic data on disaster risk and the development of planning tools to track the relationship between development policy and disaster risk 2) The collection and dissemination of best practice in development planning and policy that reduce disaster risk 3) The galvanizing of political will to reorient both the development and disaster management sectors 3 Slope Safety System for Malaysia Figure A3 presented the risk benefit ratio as a guide to adopting risk reduction options while Lee & Jones (2004) stated that humans have three main options when faced by a geohazard, such as landslides. They can do the following; • Accept the consequences and bear the costs (loss bearing and do nothing) • Respond by abandoning a site, relocating elsewhere to safer ground or changing the use of a site so as to reduce risk (choose change and risk avoidance) • Take active steps to reduce risk by limiting hazard potential and/or the potential to suffer loss (adjustment). Figure A3: The risk benefit ratio as a guide to adopting risk reduction options (after Crozier, 2004 based on Crozier, 1993) Only in the case of adjustment is landslide management involving engineering works an option and even here it is but one of the three main approaches outlined by Smith (2001) in Lee & Jones (2004), which are as follows: 1) Modification of loss burden, which involves spreading the potential losses as widely as possible, through such measures as insurance. This is essentially a loss-sharing approach with limited emphasis on loss-reduction, so total risk remains roughly the same but the financial exposure of individuals, groups etc. is reduced because it is shared between a large numbers of participants. 2) Modification of hazard events, which involves reducing the potential for loss by the use of hazard-resistant designs and engineered structures so as to safeguard lives and property and, if possible, to physically suppress the hazard potential of the geohazard concerned. 3) Modification of human vulnerability, which focuses on reducing losses through land use planning programmes that seek to relate land use zonation, building codes to hazard zonation, together with the development of preparedness programmes that aim to limit loses, especially casualties, through the installation of monitoring networks linked to forecasting and warning systems that translate into emergency actions. A more detailed division of these landslide management approaches is shown in Figure A4 which is based on the work of Burton et al. (1978), Jones (1996) and Royal Society (1992) in Lee & Jones (2004). 4 Slope Safety System for Malaysia Figure A4: Classification of adjustment choices or management options, illustrating the differences between ‘hazard management’, ‘vulnerability management’ and ‘risk management’ (after Lee & Jones, 2004) United Nations Development Programme (2004) stated that urbanization does not necessarily have to lead to increasing disaster (landslide) risk and can actually, if managed properly, help reduce it. They are a number of factors that contribute to the configuration of risk in cities. First, history is important. For example; where cities have been founded in or expanded into hazardous locations. Second, the urbanization process leads to the concentration of populations in risk-prone cities, and risk-prone locations within cities. When populations expand faster than the capacity of urban authorities or the private sector to supply housing or basic infrastructure, risk in informal settlements can accumulate quickly. Third, in cities with transient or migrant populations, social and economic networks tend to be loose. Many people, especially minority or groups of low social status, can become socially excluded and politically marginalized, leading to a lack of access to resources and increased vulnerability. The urban poor are often forced to make difficult decisions about risk. Living in hazardous location sometimes is ‘chosen’ if it provides access to work, for example; in the city centre. Urbanisation can also modify hazard patterns. Through process of urban expansion, cities transform their surrounding environment and generate new risks. The urbanization of watersheds can modify hydraulic regimes and destabilize slopes, increasing flood and landslide hazard. Spiker & Gori (2003) stated that landslide risk can be reduced by the following five approaches used individually or in combination to reduce or eliminate losses: • Restricting development in landslide-prone areas – Land-use planning is one of the most effective and economical ways to reduce landslide losses by avoiding the hazard and minimizing the risk. • Standardizing codes for excavation, construction and grading – Excavation, construction and grading codes have been developed for construction in landslide-prone areas; however, there is no nationwide standardization. • Protecting existing development – Control of surface water and groundwater drainage is the most widely used and generally the most successful slope-stabilisation method. 5 Slope Safety System for Malaysia • • Utilising monitoring and warning systems – Monitoring and warning systems are utilized to protect lives and property, not to prevent landslides. Providing landslide insurance and compensation for losses – Landslide insurance is a logical means to provide compensation and incentive to avoid or mitigate the hazard. Society and regulations require more than before that risks associated with civil engineering structures, especially infrastructures, be quantified (Nadim & Lacasse, 2004). This requires new thinking, and risk can be evaluated only by involving multi-disciplinary competences. Statistics, reliability analysis and risk estimates are useful tools that assist in the decision-making. Dealing with risk requires the use of probabilistic approaches because they provide a rational framework for taking into account uncertainties. Risk management is the process of identifying, analyzing and assessing risks to enable informed decisions on accepting or treating and controlling risks to minimize them. Figure A4 showed the process of Landslide Risk Management in a flow chart form based on Australian Geomechanics Society (2000). Risk management is necessary because some factors are uncertain and others cannot be controlled, such as rainfall. Risk is evaluated by identifying the hazards, evaluating the likelihood of a failure, evaluating the potential consequences and assessing the results for acceptability. Risk treatment is the process of selecting and implementing measures for managing the risks that have been identified. Risk treatment may involve accepting and monitoring low risks and developing mitigation plans for the higher risks. Risk mitigation is the reduction of risks by reducing either the likelihood of an occurrence or its consequences, or both. The different elements of risk management related to slope instability, identification, analysis, assessment and mitigation are briefly discussed below: Figure A5 Flowchart for Landslide Risk Management (after Australian Geomechanics Society, 2000) 6 Slope Safety System for Malaysia Risk identification Areas of potential slope instability (hazard) and the potential consequences should be mapped. The event or sequence of events leading to failure, and the sequence and consequences of events following failure are identified. Various methodologies were suggested mainly aimed at the risk identification step of risk management, as the consequences of any landslide affecting people and property are likely to be severe. Risk analysis The risks are analysed in terms of the likelihood or probability of occurrence of a slope becoming unstable and the magnitude of the potential consequences. In assessing the probability of slope failure or damage, a regional perspective of the geological precedent situation is useful. The uncertainties that must be taken into account in estimating failure likelihood include (in addition to human uncertainty and human error resulting from lack of skills or understanding): parameter uncertainty, model uncertainty and behavioural uncertainty in predicting changes in slide movement. Risk assessment Risk assessment compares estimated levels of risk against risk criteria and ranks them to establish priorities. International regulatory agencies have suggested risk criteria for land planning and managing industrial risks, e.g. the ALARP principle (Health and Safety Executive, 1998 and 1999, ANCOLD, 1994 and 1996 in Nadim & Lacasse, 2004 or Australian Geomechanics Society, 2000) as presented in Figure A6. Societal risks may be expressed as curves of annual frequency of a hazard causing fatalities (Figure A7). On the proposed diagram, there is an area of unacceptable risk. At the other end of the scale, there is a region of broadly acceptable risk, which the majority of community will accept. Between these two regions there is the “as low as reasonably practicable” or ALARP area, where risks are not necessarily accepted but are tolerated because it is unrealistic and impractical to eliminate the risk. The ALARP principle is controversial, and not universally accepted among risk experts (Rackwitz, 2000 in Nadim & Lacasse, 2004) Risk mitigation Risk mitigation is the process of selecting and implementing measures for managing the risks that have been identified. Low priority or acceptable risks may require only monitoring and periodic review. Other risks will require the identification and evaluation of treatment options and the implementation of mitigation measures. Quantitative risk assessment can be used to compare the relative effectiveness of different mitigation options. 7 Slope Safety System for Malaysia Figure A6: Evaluating and responding to risk: the ALARP (as low as reasonably practicable) approach (after Crozier, 2004 based on Helm, 1996 and HSE, 1992) Figure A7: A typical diagrams referred to as FN diagrams representing the frequency of events of given magnitude (number of deaths) plotted against the number of deaths represented by those events (after Australian Geomechanics Society, 2000) 8 Slope Safety System for Malaysia The way to zone landslide risk is to do a Quantified Risk Assessment (QRA). The essence of risk management and the role of QRA within the context of risk management are shown in Figure A8. Figure A9 presented the general risk management cycle as described by Alexander (2000, 2002) in Crozier & Glade (2004) while Figure A10 presented the hazard management cycle based on Carter (1991) in Crozier (2004). Figure A8: Framework of risk management (after Ho, Leroi & Roberds, 2000) Figure A9: The general risk management cycle as described by Alexander (2000, 2002) in Crozier & Glade (2004) 9 Slope Safety System for Malaysia Figure A10: The hazard management cycle (after Crozier, 2004 based on Carter, 1991) Royal Society (1992) stated that at the most of general level, the process of risk management can be understood in terms of the three basic elements of organizational control theory: the setting of goal, whether explicitly or implicitly; the gathering and interpretation of information, and action to influence human behaviour, to physical structures or both. Each of the three elements is problematic and disputed. Who is to bear what level of risk, who is to benefit from risk-taking and who is to pay? Where is the line to be drawn between risks that are to be managed by the federal, state and those that are to be managed by individuals, groups or corporations? Where is the line to be drawn between minimizing accidents by anticipation and promoting resilience to cope with whatever failures may arise and between attempts to influence the causes of hazards as against measures to change their effects? What information is needed for ‘rational’ risk management and how should it be analysed? What actions make what difference to risk outcomes? Who evaluate success or failure in risk management and how? Who decides on what should be the desired trade-off between different risks? There is no general consensus on such questions. Yet life-or-death risk management does and must, take place in all societies through some sort of institutional process. Common misconception among engineers and scientists on Slope Safety System is that they often consider the Slope Safety System is the same as Landslide Risk Assessment or Slope Ranking System. Royal Society (1992) stated that some have argued that risk assessment and risk management are overlapping, but separate, tasks. The claim is that the former is predominantly scientific and concerned with the establishment scientific and concerned with the establishment of probabilities, whereas the latter is primarily legal, political and administrative. The distinction between ‘scientific’ assessment and ‘political’ management is contested by those who argue that it is impossible to disentangle social values and worldviews from the process of identifying, estimating and evaluating risks, and that, at least from a social view point, it is unhelpful to conceive risk as if it were a single uniform substance. In public policy, ‘risk management’ has been commonly used to refer to an analytic technique for quantifying the estimated risks of a course of action and evaluating those risks against likely benefits. The assumption behind this approach is that a risk-free society is impossible, that all risk reduction involves costs, and that explicit valuation of benefits and costs (including the value of human life) can help to produce decisions that are consistent over different areas of public policy and that balance overall risks against overall benefits. This approach to risk analysis is well-established and influential. 10 Slope Safety System for Malaysia Wong & Ho (2006) stated that landslide risk is a measure of the chance of occurrence of slope failure causing a certain amount of harm (e.g. fatalities and economic losses), and can be quantified as the product of the probability and consequence of failure. Landslide risk assessment is the process of identifying the landslide hazard and estimation of the risk of the hazard. Landslide risk management comprises and estimation of the landslide risk, deciding whether or not the risk is tolerable, exercising appropriate control measures to reduce the risk where the risk level cannot be tolerated. In more global context, landslide risk management also refers to the systematic application of management policies, procedures and practices to the tasks of identifying, analyzing, assessing, mitigating and monitoring landslide risk. Further discussion on risk management and vulnerability of landslide hazards is presented in Appendix D. Malone (2003) stated that the other common mistake is to forget that landslide threat consists of two components: likelihood of occurrence and consequence of occurrence. Many systems for ground characterization (or landslides ranking system) only consider landslide occurrence (or landslide “susceptibility”). Many of the so-called risk zonation systems do not actually consider consequence in a useful manner. The way to zone landslide risk is to do a Quantified Risk Assessment (QRA). The institutional players in risk and hazard management are very important as Douglas (1987) in Royal Society (1992) stated that an ‘institution-free’ approach to major risk management is not an option: ‘individuals in crises do not make life and death decisions on their own. Who shall be saved and who shall die is settled by institutions. Putting it even more strongly, individual ratiocination cannot solve such problems. An answer is only seen to be right if it sustains the institutional thinking that is already in minds of individuals as they try to decide’. A process for handling risk to satisfy the needs of the parties involved, referred to as ‘risk management’, had become well-established in the hazardous industry (Royal Society, 1992) in Malone (1997b). Malone (1997b) also highlighted that in Hong Kong, the landslip problem is analysed using the risk management approach and such an analysis provided useful insights and pointers for further development of the Slope Safety System Adopting a risk management approach requires the calculation of risk and the making decision on the level of risk including cost benefit analysis and non-financial cost. In order to design a National Slope Safety System for Malaysia, a review on existing established Slope Safety System such as those in Hong Kong was made. The design of such system will also base on risk management principle as established in Hong Kong. Figure A11 presented the schematic representation of the integrated risk management process (Fell et al, 2005) 11 Slope Safety System for Malaysia Figure A.10: Schematic representation of the integrated risk management process (after Fell et al, 2005) References Australian Geomechanics Society, 2000, Subcommittee on Landslide Risk Management: Landslide Risk Management Concepts and Guidelines, Australian Geomechanics, Vol. 35, Issues 1, pp 49-91. Committee on the Review of the National Landslide Hazards Mitigation Strategy, National Research Council, 2004, Partnerships for Reducing Landslide Risk: Assessment of the National Landslide Hazards Mitigation Strategy, The National Academic Press, USA, pp 144 [available at http://www.nap.edu/catalog/10946.html assessed on 21/11/2005] Crozier, M. J., 2004, Management frameworks for landslide hazards and risks: Issues and options in Glade, T., Anderson, M. & Crozier, M. J., Landslide Hazard and Risk, John Wiley & Sons Ltd, UK, pp 331-400 Crozier, M. J. & Glade, T., 2004, Landslide hazards and risk: Issues, concepts and approach: in Glade, T., Anderson, M. & Crozier, M. J., Landslide Hazard and Risk, John Wiley & Sons Ltd, UK, pp 1-40 Fell, R., Ho, K. K. S., Lacasse, S. & Leroi, E., 2005, A framework for landslide risk assessment and management in Hungr, Fell, Couture & Eberhardt (eds), Landslide Risk Management, Taylor & Francis Group, London, pp 3-25 Ho, K., Leroi, E. & Roberds, B., 2000, Quantitative Risk Assessment: Application, Myths and Future Direction, GeoEng2000: International Conference on Geotechnical & Geological Engineering, Volume 1: Invited Papers, Melbourne, Australia, pp 269-312. 12 Slope Safety System for Malaysia Lee, E. M. & Jones, D. K. C., 2004, Landslide Risk Assessment, Thomas Telford, London, pp 454. Malone, A. W. 1997, Risk Management and Slope Safety in Hong Kong, Transactions of the Hong Kong Institution of Engineers, Vol 4, No. 2 & 3, pp 12-21. republished in Li, K. S., Kay, J. N. & Ho, K. K. S. (eds), 1998, Slope Engineering in Hong Kong, A. A. Balkema, Rotterdam, pp 3-17. Nadim, F. & Lacasse, S., 2004, Mapping of landslide hazard and risk along the pipeline route in Sweeney, M. (Ed), Terrain and Geohazard Challenges Facing Onshore Oil and Gas Pipeline, Thomas Telford, London, pp 117-128. Royal Society, 1992, Risk: Analysis, Perception and Management, Report of a Royal Society Study Group, Royal Society, London, pg 201. Spiker, E. C. & Gori, P. L., 2003, National Landslide Hazards Mitigation Strategy: A Framework for Loss Reduction, Circular 1244, U.S. Geological Survey, Virginia, USA, pp 56. United Nations Development Programme, 2004, Reducing Disaster Risk: A Challenge for Development, John Swift Print Co., USA, pp 146 Wong, H. N. & Ho, K. K. S., 2006, Landslide Risk Management and Slope Engineering in Hong Kong, Proceedings of Seminar on The State-of-the-practice of Geotechnical Engineering in Taiwan and Hong Kong, Hong Kong Institution of Engineers, pp 101-141. 13