https://doi.org/10.20965/jdr.2021.p0571 Factoring Multi-Hazard Risk Perception in Risk Assessment and Reduction Measures in Landslide and Flash Flood Prone Areas – A Case Study of Sichon District, Nakhon Si Thammarat Province, Thailand Paper: Factoring Multi-Hazard Risk Perception in Risk Assessment and Reduction Measures in Landslide and Flash Flood Prone Areas – A Case Study of Sichon District, Nakhon Si Thammarat Province, Thailand Indrajit Pal∗,† and Jessada Karnjana∗∗ ∗Disaster Preparedness, Mitigation and Management (DPMM), Asian Institute of Technology (AIT) Moo 9, Km 42 Paholyothin Highway, Klong Luang, Pathumthani 12120, Thailand †Corresponding author, E-mail: [email protected], [email protected] ∗∗National Electronics and Computer Technology Center (NECTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, Thailand [Received November 25, 2020; accepted March 26, 2021] This study’s purpose is to analyze the degree of risk hoods in this area mostly come from agricultural activi- and vulnerability involved in landslide and flash flood ties, such as rice fields and orchards. Thus, most people prone community areas in Thepparat sub-district, try to change the land use pattern without visualizing the Sichon district, Nakhon Si Thammarat province, consequences. For example, they change the forest area Thailand. It also aims to analyze and understand to a plantation area and cut the slope of the mountain, the socio-economic impacts on the community at the which could cause flash floods and landslides. The exten- household level, and assess the community’s risk and sive floods in 2011 also affected the district and caused vulnerability by examining its risk perception. The massive landslides. Apart from private properties, lots of risk perception was done using focus group discus- government facilities, such as roads, bridges, small dams, sions and a questionnaire survey with key stakehold- and drainage systems were destroyed, and the total dam- ers. It mainly focused on how the risk of landslides ages of all districts amounted to around 320 million baht. and flash floods influences the community’s risk per- As defined by researchers [1, 2], risk perception refers ceptions, which was tested in two parts: at the orga- to people’s subjective judgment of an event’s risk prob- nizational and community levels by focusing on gov- ability based on their different perspectives, experiences, ernment officials and households, respectively. A cor- and knowledge. Therefore, risk perceptions of landslides relation matrix was used to understand the relation- and flash floods differ from person to person based on ship of the indicators selected. The Pearson correla- their individual experiences and knowledge. Society, cul- tion result has shown that the degree of risk aware- ture, and beliefs can also play contributing roles [3]. This ness positively correlates with the income level, educa- subjective judgment of landslide and flash flood risks tion level, and controllability, signifying that the risk would determine the extent to which people are involved of landslides and flash floods influences household risk with national policies and laws. Preparedness and miti- perceptions. The qualitative assessment recommends gation research studies enhance landslide and flash flood community-level preparedness as being paramount to awareness, preparedness plans and programs, as well reduce the risk for a resilient community. as coping activities and resilience skills of the commu- nity [4]. Furthermore, the current state of attitudes and perceptions of the stakeholders, authorities, and imple- Keywords: community preparedness, flash flood, land- menters can play a crucial role in influencing the final slide, multi-hazard, risk perception amount of intended involvement, effort, and resources that would be applied at the local level [5]. Therefore, a new trend of study concerns the change 1. Introduction of vulnerability conditions that can bring about disas- ter risk reduction (DRR), such as the potential of post- Sichon District, Nakhon Si Thammarat Province is lo- disaster loss [6, 7]. The disaster risk management ap- cated in the southwest of Thailand, and is surrounded by a proach can address each of the components of risk, such high altitude mountain on the west and a plain area on the as hazard intensity and probability, as well as popula- east. Moreover, the mountain’s bedrock comprises gran- tion, critical infrastructure, and vulnerability [8, 9]. More- ite that has a high potential of sliding. Furthermore, the over, since the assessment and perception of risks dif- Sichon district is also prone to flash floods due to heavy fers amongst people in each community, these differences or even moderate rainfall situations. The primary liveli- can be integrated to find out the best information on de- Journal of Disaster Research Vol.16 No.4, 2021 571 © Fuji Technology Press Ltd. Creative Commons CC BY-ND: This is an Open Access article distributed under the terms of the Creative Commons Attribution-NoDerivatives 4.0 International License (http://creativecommons.org/licenses/by-nd/4.0/). Pal, I. and Karnjana, J. cision making, which can then be provided to decision- makers for implementing plans, funding, and disaster risk management projects [10]. There is a need to estab- lish some contextual linkages between the multi-hazard risk perceptions of the decision-makers and the commu- nity, since these could grossly influence the DRR deci- sion making process for the district and general province. The present study analyzed the involvement of the stake- holders in DRR decision-making. Its outcome could lead to the identification of disaster risk management is- sues/conditions, that need to be addressed based on the risk perceptions of the local people, multi-stakeholders, multi sectors, and departments [11]. Its results could also provide decision-makers in the community with very im- portant recommendations for planning projects and prac- (a) tices more efficiently [12]. 2. Background of the Study Area Nakhon Si Thammarat – the second largest province in the southern part of Thailand – has a varied topography with three distinct features: a mountain range in the mid- dle, a plain area on the eastern coast, and a plain area in the west. The study area is “Thepparat” (Tambon/sub-district) located at 8◦86N and 99◦77E to the north of Nakhon Si Thammarat province, covering an area of around 81.198 km2 (Fig. 1). Its geographical condition is high mountains, about 1,340 m above sea level, flat foot, and plain areas. It has many hills, such as Sam Thep, Teng, (b) and Youn Thao, which create this area’s main canals, Fig. 1. (a) Nakhon Si Thammarat province, Thailand, namely Tha Thon, Sam Thep, Phean, and Pean canals. (b) Thepparat administration. Based on its geographical conditions, the Thepparat Tam- bon community is prone to landslide and flash flood haz- ards [13]. Tha Thon canal. In particular, heavy losses and dam- ages were faced by village number 10 of Thepparat sub- 3. Hazards, Vulnerability, and Risks of Nakhon district, where 4 people died, 48 houses were completely Si Thammarat damaged, 68 moderately damaged, and government in- frastructure for public services, such as roads, bridges, Nakhon Si Thammarat province – located on the east small dams, and drainage system were also destroyed (Ta- coast of the Gulf of Thailand – has a tropical monsoon ble 1). The cost of total damages in all districts were esti- climate, with an annual rainfall of 1,800–2,200 mm. The mated at around 320 million Thai baht. rainy season starts around the middle of May and lasts until mid-January [14]. Landslide and flash flood hazards in Nakhon Si Thammarat are closely associated with the 4. Data Collection Methodology monsoon and typhoons, wherein heavy rainfall can cause slope failures. Heavy rains, combined with poor building The tools and techniques used for collecting the data practices and deforestation, result in landslides and flash and information in this study were designed to measure floods (Table 1) [3]. Communities affected by disasters and evaluate the local community’s risk perceptions. The generally do not receive any warning, and the rural and primary data were gathered through a structured question- economically poor communities are likely to be most af- naire administered to the community, face-to-face inter- fected. views, field observations, and focus group discussions. Sichon district administration reported flash floods and Secondary data such as the map and history, background rainfall-induced landslides during March 23–31, 2011, information of the study area, agricultural land, plans and that were triggered by heavy rainfall (more than 100 mm policies from the Department of Disaster Prevention and per day) for several days. The event was severe, and Mitigation (DDPM)’s provincial office and Department of harmed communities in mountainous areas and along the Mineral Resources were collected from an extensive liter- 572 Journal of Disaster Research Vol.16 No.4, 2021 Factoring Multi-Hazard Risk Perception in Risk Assessment and Reduction Measures in Landslide and Flash Flood Prone Areas – A Case Study of Sichon District, Nakhon Si Thammarat Province, Thailand Table 1. Historical landslides and flash floods in Nakhon Si Thammarat province [15]. Date Hazard Location Losses and Damages October 25–26, Tropical Storm Landfall at Laem Talumphuk, 900 people died and more than 10,000 1962 Harriet caused Pak Phanang District, Nakhon Si were homeless. astormsurge Thammarat November 22, 1988 Landslides and Ban Kathun Nuea, Phipun District and 230 people died, and damages worth debris flow Ban Khiri Wong, Lan Saka District, 1 billion Thai baht. Nakhon Si Thammarat November 29, 1993 A tropical Nakhon Si Thammarat 23 people died and damages worth depression can 1.3 billion Thai baht. cause flooding November 3, 1997 Tropical Storm Nakhon Si Thammarat 164 people died. Linda October–December Flooding Many provinces in Southern Thailand 80 people died. Damages up to 54 bil- 2010 lion Thai baht.