BASIC METHODOLOGY FOR LANDSLIDES RELATED DISASTER PREPAREDNESS IN SRI LANKA

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1 BASIC METHODOLOGY FOR LANDSLIDES RELATED DISASTER PREPAREDNESS IN SRI LANKA G. Weerawansha, University of Peradeniya, Sri Lanka H. A. A. Peiris, University of Peradeniya, Sri Lanka A. K. Kulatunga, University of Peradeniya, Sri Lanka S. B. Ekanayake, UNESCO Central Asia, Sri Lanka P. B. R. Dissanayake, University of Peradeniya, Sri Lanka Abstract Recent disasters in the world show us importunacy of level preparedness and what we can save from being prepared beforehand. Disaster preparedness also becomes essential part of our life since frequency of disaster occurrences have increase considerably in last couple of years. It is widely accepted that the main reason for unexpected weather patterns are caused by the climate change due to the green house effect faced by the earth. Due to sudden changes in the climate, there will be storms with high magnitude to a large region within a very short period of time thereby creating havoc situations leading to floods in the lower catchment areas and lands slides in the hilly areas. Conversely, due to rapid growth of population especially in South Asian region, the land usage has been increased many folds and suitable and safe lands for sheltering are diminishing rapidly. Hence, majority of poor people tends to live in places in steep slopes which lead to landslides in hilly areas and lower marshy lands which are subjected to flooding very often. Though there is a separate ministry and different organizations to handle disasters in Sri Lanka, still it can be seen that large number of people suffers from natural disasters and fair number of them even losing their lives. This may be mainly due to lack of knowledge on disasters and carelessness of the majority of them. Therefore this research focuses to find the level of awareness of probable disasters and their disaster preparedness in selected sample of people in central highlands of Sri Lanka. Through this study it is expected to develop low cost indicators to highlight the possibility of disasters in these areas and to empower them for disaster preparedness through non-formal education methods. Awareness was checked by conducting a survey in different parts of central highlands of Sri Lanka. The empowerment is being achieved through non formal education methods for the elders. These are simple methods which will guide anybody to recognize the changes and to act on them. The initial stages of the project showed positive

2 results and majority of the stakeholders have shown enthusiasm towards the programmes conducted under this research. Keywords: Disaster Preparedness, Landslides, Non-formal education, landslide indicators, empowerment 1. Introduction Land slide is a geological phenomenon which includes wide range of ground movement. A landslide occurs when part of a natural slope is unable to support its own weight. The action of gravity is the primary driving force for a landslide to occur. And it occurs when the stability of a slope changes from a stable to an unstable condition. A change in the stability of a slope can be caused by a number of factors. These factors can categorize in to main two groups such as natural case of landslide occurrence and human related activities. Some of these factors are listed below. Natural incident includes Groundwater pressure variation, heavy rains, loss or absence of vertical vegetative structure, erosion of the toe of a slope, earthquakes adding loads to barely-stable slope and etc. Human related activities are vibrations from machinery or traffic, blasting, earthwork which alters the shape of a slope, in shallow soils, the removal of deep-rooted vegetation that binds colluviums to bedrock and etc. The land slide can be categorized according to type of the material flow and the place of it occurs, we are calcifying the landslides. There are 6 main types of landslides which are occurs due to Debris flow, Earth flow, Slump, Rock sides and Creep. Landslides are nothing new to Sri Lankan community. There are number of fairly large landslides occurred in Elapatha (1986), Abepura (2003), Helauda (2003, 2006), Naketiya (1998) which claimed many lives to name few. Apart from lives these damage infrastructures as well. Some highway stretches of A 4 in Beragala & Koslanda areas and Puswellawa in A5 had to extensively repaied due to landslides in last couple of decades. Further due to Watawala landslide in 1990, upcountry railway track was damaged and trains could not operate for couple of months. Though there are number of landslides occurred Sri Lanka, still the awareness and preparedness about landslides among the local community is very low and this proves recent incident happened in central part of the island. Most of the deaths are occurred because of poor knowledge and carelessness about the disaster. Even though there is a separate ministry and a centre for Disaster management in Sri Lanka, still disaster preparedness has not gone into grass root levels of the villages. Therefore, this research tries to address this disaster awareness and preparedness issue while identifying the current situation of the problem and to address them same time adapting none-formal education strategies. Rest of the paper is organized as follows; section 2 present the methodology adapted to identify the level of knowledge and the strategies adapted to educate and empower them. Section 3 is allocated to present data collection and analysis and section 4 present the conclusion and this is followed by discussion the section 5.

3 2. Methodology As explained previously, our research objectives are two folded: to identify existing know how of landslides related disaster preparedness and educating empowering people who live closer to landslides. To match with main objectives in this research, a methodology was formulated simultaneously to gather information related to the knowledge of the landslides prone dwellers and to educate them to empower with disaster preparedness. The methodology consists of two sections: one to identify current situation on landslides related disaster preparedness and two, on awareness programme. These two sections sub divide into several stages, and interlink in different layers as shown in Figure 1. The sub divisions and their branches are shown in Figure 2. For the information gathering purposes, a field survey was carried out in selected DS divisions of Central and Uva provinces which are highly subjected to landslides. A questionnaire was developed in this regards and it mainly consist of seven categories: personal and demographical information, land condition, house construction related information, drainage related information, knowledge about landslides, disaster preparedness etc. The interviewee were also selected form Civil engineering undergraduates who are familiar with selected DS divisions in order to gather all necessary information as well as to observe the sites with soil types, soil retaining structures, house construction etc. The sample size for this survey was 60 families in three DS divisions and these families were selected randomly based on the landslides susceptible locations. The awareness programme consist of: basic knowledge on landslides, reasons for landslides, different types, basic indicators for landslide detection, legal issues related with house construction and rain water discharge and disaster preparedness etc. The awareness programme was done with the help of videos, photographs, animations, presentations, discussions etc. With the help of a laptop carried by each group who did the survey. Selection of areas and Dwellings Identify the easy to design indicators Design & development of information collection model Design and develop the low cost landslide prediction indicators Collect information by a survey and field visit Conducting awareness Programs by none formal education methods Feedback Analysis of data Conclusion

4 Figure 1: Proposed Methodology for disaster awareness and preparedness programme Personal Educational Dwellers Information Designing Foundation Structural Information Construction maintenances Types of land slide Why lands occur Knowledge related to landslide How to mitigate the landslide Water drain system Soil types and ground coverage Surrounding information Retaining walls Figure 2: Sub categories and their branches used for information gathering purposes in the field survey

5 The awareness and education programme consist of following categories: clear explanation of what is a landslide, different types, aims and objectives of the awareness programme, what we can do to prevent or minimize landslides, symptoms of landslides, different indicators to predict landslides, how to prepare landslide indicators, preparedness for landslides, precautions to be taken during a landslide, legal background on environmental issues, traditional soil conservation methods, how to cope up with landslides. These explanations were done with the help of power point presentations using laptops. These were done at each house for family members and this was most effective since group was small and everybody has a chance to get verified their doubts. The presentation consisted of videos and some photos other than descriptions in Sinhala language. 3. Data collection and Interpretation Two different areas Peradeniya (Gatabe), Diyatalawa, which are highly subjected to landslides, were selected from Kandy and Badulla districts respectively for this research. Since this research is a ongoing process we are expecting to span this into further areas in future. When we select the places we referred to the maps prepared by National Disaster Management Centre which indicates landslides prone areas which is shown in Figure 3 and Figure 4. Following factors were considered when selecting the areas: Potential of land slide, Density of the live hood, density of buildings, knowledge of the people and Geographical factors. Figure 03: The frequency of landslides has increased in the recent years. Figure 04: Distribution of land slide hazards and other natural disaster in Sri Lanka For the data collection and to educate people we selected 3 rd year Civil Engineering undergraduates since their background knowledge on disasters, soil types and structures were essential for this programme. This group was train by experts in landslides and disaster management and none-formal education and social sciences background. Discussions were held related to landslides, Structures under dynamic loading, landslide mitigation, Laws related to contraction and development and non-formal education and how to conduct field survey. After

6 these training sessions the groups were taken into pilot tour to train them how to conduct a filed survey. 4. Results and Discussion Based on the information gathered, following variations were investigated. Level of education versus adaptation of proper construction practises, adaptation of proper drainage system, awareness about landslides and disaster preparedness etc. In addition, the percentage awareness s were calculated. The Figure 5 and Figure 6 show the awareness about disasters good construction practises vs. Level of education and percentage awareness s of each main categories in the questionnaire. In addition, Table 1 shows information about likeliness to landslides of each site visited given. Figure 5: Good construction practice vs. level of education

7 Figure 6: Percentage awareness s of each main categories in the questionnaire

8 Table 1: Information about likeliness to landslides of each site visited given Category Percentage House without house planes 72 Technical person doesn t see the condition of the site 66 Hose plane doesn t approved by the government 69 House without foundation 6 Foundations not related to the house plane 53 Technical person doesn t see the condition of the soli 62 House without rain water drain system 66 House without good waste water drain system 75 house without rain gutters 62 Houses without rain water tank 19 Lands with soil erosion 62 Not educated about construction lows 69 Not educated about environmental lows 50 unpreparedness to disasters 75 Previous happens disasters 72 Not educated about landslides 62 bad soil conditions 78 Ruins retains walls 53 Unprotected retains walls 67 potential to land slide 93 It can be clearly seen that level of education has a direct impact on disaster preparedness as well as best environmental practises such as soil erosion prevention, drainage water handling etc. Furthermore, it can be seen that when level of education increases dwellers keenness on this awareness programme also high and their willingness to participate this programme as well as active interaction also high. 5. Conclusion It can be clearly seen that though there are number of organizations involve in this area, still the general public who are very much subjected to these disasters are unaware about many important factors. This is visible in both areas we covered. Furthermore, it can be seen that it is important for them to educate from first instance how to select a safe place to construct a house and what should be the proper and safe methodology to put up permanent structures and to maintain and manage other functions with the environment and neighbours. Furthermore, it is noted that

9 expansion of this research to other areas will enhance the awareness programme since difference geomorphic areas have different issues such as soil conditions etc. 6. References Kumari M. Weerasinghe, Anuradha Malalasekara,Evangeline Ekanayake 'Learning to live with LANDSLIDES Natural Hazards and Disasters ' 2006, Originally developed by the Asian Disaster Preparedness Centre, Thailand. (2002) Adapted for Sri Lanka I. Hadzinakos, D. Yannacopoulos, C. Faltsetas,K. Ziourkas 'Application of the MXNOgA decision support system to the evaluation of landslide favourability in Greece' European Journal of Operational Research 50 (1991) G. Lollino *, M. Arattano, M. Cuccureddu 'The use of the automatic inclinometric system for landslide early' Physics and Chemistry of the Earth CNR-IRPI, Strada delle Cacce 73, Torino 10135, Italy 27 (2002) YIN Kunlong, CHEN Lixia, 'Regional Landslide Hazard Warning and Risk Assessment' ZHANG Guirong Earth Science Frontiers,Volume 14, Issue 6, November 2007 Online English edition of the Chinese language journal 2007, 14(6): Paolo Frattini, Giovanni Crosta, Alberto Carrara'Techniques for evaluating the performance of landslide susceptibility models' Paolo Frattini, Giovanni Crosta, Alberto Carrara