ADAPTATION OF LAND USE AND HOUSES IN THE UPPER MEKONG DELTA’S DEEP FLOODING AREA NGUYEN KHANH VAN (B.Arch) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ARTS (ARCHITECTURE) DEPARTMENT OF ARCHITECTURE NATIONAL UNIVERSITY OF SINGAPORE 2012 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Acknowledgements It would not have been possible to fulfil this thesis without the help and support of kind people around me My heartfelt gratitude goes to my Supervisors, Prof Joseph Lim Ee Man and Prof Nirmal Tulsidas Kishnani, for their guidance, support and patience For inspirations, discussions and academic input, I would like to thank Prof Giang Ngoc Huan, Prof Le Anh Tuan, Nguyen Nghia Hung, Dau Van Huan, Yenny Rahmayati, Hannah K Griffiths, Adi Santosa, Tran Thanh Duong, and Huynh Le Hai Chau My sincere gratitude goes to organizations and people supporting me in my fieldtrips, especially owners of roughly fifty studied houses, for their enthusiasm and kindness I would like to thank my fellow graduate students in CASA and my Friends at the National University of Singapore; some have been mentioned above, Nikhil Joshi, Nayada Nakhasit, Su Jan, Nguyen Tan Trong, Huynh Le Ngoc Thanh, Huynh Kim Tho, and my Friends Tran Hao Thac, Truong Thi Thu Van, Tran Thi Ngoc Thanh… the list would be very long, for their friendship and care Finally, I owe my deepest gratitude to my beloved family Thanks to my Father Nguyen Huu Tri, my Mother Nguyen Thi Le Hang, and my Sister Nguyen Ngoc Phuong Van for their endless love, care, and inspirations Thanks to my Husband, Nguyen Chi Hieu, for his deep love, understanding, and helpful discussions i Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area I dedicate this thesis to my family and the people in the Mekong Delta ii Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Table of Contents Acknowledgements i Table of Contents iii Summary vii List of Tables ix List of Figures x List of Abbreviations xix Chapter Introduction 1.1 Overview of thesis 1.2 Research background 1.2.1 The upper Mekong Delta’s deep flooding area 1.2.2 Research gaps 1.3 Research questions and objectives 1.4 Research Method 1.4.1 The importance of “adaptation” 1.4.2 Method 12 1.5 Thesis outline 16 Chapter Current Environmental Challenges 18 2.1 The Mekong Delta 18 2.2 The studied area – upper part of Mekong Delta’s deep flooding area 21 2.3 Current environmental challenges 22 2.3.1 Flooding 22 2.3.1.1 Seasonal floods from the Mekong River 23 2.3.1.2 Tides 40 2.3.2 Other threats 41 2.3.2.1 Salinity intrusion 41 2.3.2.2 Soil acidification 43 2.3.2.3 Seasonal tropical storms 44 2.3.2.4 Climate change 44 2.3.2.5 Pollution 45 2.3.2.6 Reduction of fishery resources 47 2.4 An uncertain future 48 iii Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Chapter Existing Literature on Adaptation of Houses and Land Use 50 3.1 Houses in the Mekong Delta’s deep flooding area 50 3.1.1 Houses built by the people 56 3.1.2 Houses built by the government 58 3.2 Land use planning 63 3.2.1 Master plan of the Mekong Delta for 2020 by SIUP-South (2008) 63 3.1.2 Flood control planning by SIWRP (1998b) 66 Chapter Current Adaptation to Floods 69 4.1 Adaptation of land use: Infrastructure development dealing with floods 70 4.1.1 Flood control infrastructure development 70 4.1.2 Impacts of flood control infrastructure on floods 74 4.1.3 Impacts of flood control infrastructure in the studied area 77 4.2 Adaptation of community 78 4.2.1 Characteristics 78 4.2.2 The role of community in adapting to floods 79 4.3 Adaptation of houses in the studied area 80 4.3.1 Characteristics of houses in the studied area 81 4.3.1.1 Layout of houses in the studied area 81 4.3.1.2 Types of houses in the studied area 85 4.3.2 Current adaptation strategies of houses 96 4.3.2.1 Location and settlement patterns 96 4.3.2.2 The issue of elevation 113 4.3.2.3 The issue of durability – Choice of materials and construction technology 121 4.3.2.4 Flexibility 125 4.3.2.5 Landscape 126 4.3.2.6 Other criteria: land ownership, main source of income, and wealth 131 4.4 Limitations of current adaptation of houses in the studied area in current context 132 Chapter Future Projection of Hydrology Change and Adaptation of Land Use and Houses in the upper Mekong Delta’s deep flooding area 134 5.1 Future projection in relation to hydrology change 134 5.1.1 Irregular seasonal floods 135 5.1.1.1 Irregular timing and duration of seasonal floods 135 5.1.1.2 Larger amplitude of flood fluctuation 135 5.1.2 Sea level rise 138 iv Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area 5.1.3 More regular and intense typhoons 141 5.1.4 Degradation of soil quality 141 5.1.5 Lack of fresh water and degradation of water quality 143 5.1.6 Reduction of fishery resources 143 5.2 Limitations of adaptation of land use and houses 145 5.2.1 Land use 145 5.2.1.1 The Mekong Delta master plan for 2020 145 5.2.1.2 Drawbacks of flood control infrastructure 147 5.2.2 Houses 147 5.3 Challenges to livelihoods 150 5.4 An approach for land use planning and adaptation of houses 152 5.4.1 An approach for land use planning 152 5.4.1.1 Land use planning and livelihoods 154 5.4.1.2 Land use planning and hydrology 158 5.4.2 Adaptation of houses in the studied area 166 5.4.2.1 Adaptation of the floor level to more intense floods 167 5.4.2.2 Initial observations and suggestions of adaptive measures to improve durability of houses 171 5.4.2.3 Initial suggestions of water harvest and storage, and domestic sewage systems for houses 179 5.4.2.4 Community 181 5.5 Chapter summary 184 Chapter Conclusion 185 6.1 Findings of the thesis 186 6.1.1 Challenges of the studied area in present and future contexts 186 6.1.2 Adaptation at land use scale 188 Current adaptation 188 Limitations of adaptation 188 An approach for land use planning 191 6.1.3 Adaptation at housing scale 192 Current adaptation 192 Limitations of current adaptation 193 An approach for adaptation of houses 194 6.2 Contributions of the thesis 194 6.3 Prospects for future research 196 v Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Bibiliography 198 Appendices 209 Appendix Photos illustrating severe flood in 2011 209 Appendix 2A Hydropower dams on the Mekong River’s mainstream 218 Appendix 2B Statistics of main hydraulic infrastructure in the Mekong Delta 219 Appendix An analysis of the studied houses 220 Appendix House study sample 239 vi Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Summary This thesis studies the adaptation of land use and houses in the upper Mekong Delta’s deep flooding area The studied area, a major rice-cultivation area in Vietnam, is the most deeply inundated annually in the Mekong Delta While severe flooding is detrimental to the safety of inhabitants, the built environment and agricultural production, annual inundation from the Mekong River provides fertile sediments and fishery resources, and renews the soil and water quality However, there is a threat to the environment of the studied area because the flooding patterns have changed as a result of climate change, sea level rise, water resources management, and upstream dam construction The aim of this research is to study the current adaptation of land use and houses, and its limitations in the possible future context relating to hydrology change in the upper Mekong Delta’s deep flooding area This thesis examines land use and houses in their connections with critical issues, to provide an overview of and insights into adaptation to environmental change While this study does not aim to reach specific design solutions, it frames the problem, suggests an integrated approach, and raises the questions for land use planning and housing design Data was analyzed by reviewing the literature about land use planning, houses, and hydrology in the studied area, site visits were made to observe the community, and to interview the people and document the house layouts The current adaptation strategies of houses are examined in terms of location and settlement patterns, elevation of houses, durability and construction materials, flexibility, and landscape In addition, this research postulates the future context with the current trend of irregular seasonal flooding, sea level rise, more frequent vii Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area and intense typhoons, reduction of fishery resources, degradation of soil and water quality, and lack of the fresh water Examining these current adaptation strategies against the projected future context, this study reveals the limitations of the status quo and challenges to the built environment resulting from changes in hydrology and the livelihoods of people This thesis suggests that land use planning in the upper Mekong Delta’s deep flooding area should be examined in relation to hydrological phenomena and their impact on livelihoods Traditional livelihoods may not be sustained in the future, so research on the adaptation of livelihoods to hydrological change can provide input for future land use planning in the studied area Regarding the relationship between land use and hydrology, the approach of land use planning should be one of living with the floods and reserving spaces for floods, rather than one of controlling or preventing the floods Land use planning and flood control planning should be integrated, which requires collaboration of relevant institutions The study attempts a land use approach which considers flood risk, green and blue network and farmland, and the current fabric of the area These layers of knowledge would help determine locations and scales of spaces reserved for water and development of the built environment In addition, at the scale of the dwelling, this thesis suggests the issues need to be considered, including elevation, durability, the water harvest and storage systems, and the domestic drainage and sewage systems in response to the future threats For the community, it is necessary to create an awareness of the challenges ahead Community-based adaptation is also a potential approach in the studied area to foster resilience of the community in dealing with change viii Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area List of Tables Table Concepts of adaptation and mitigation to hydrology change in the Mekong Delta 10  Table Framework to examine the problem 13  Table Average income of people in the eight economic areas of Vietnam 20  Table Land use in the Mekong Delta 21  Table Facts about the studied area 22  Table Percentage of people with access to water supply and owning latrines 46  Table Settlement patterns of houses directly connected to roads and canals 101  Table Sea level rise (cm) relatively to the period of 1980-1999 138  Table Approximate annual average estimates of Mekong sediment and nutrients deposition 142  Table 10 Vulnerability of houses in the studied area to typhoon and suggestions of solutions 172  ix Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Elevation Section Floor plan Roof plan Figure 36. "Ba gian" typology  Source: Vu (2004)     “Xếp đọi” typology All functional spaces are organized in one floor plan as following order from the entrance: verandah, living/family room, bedrooms, dining space and kitchen, then other ancillary spaces Based on the floor plan, the roof includes several gable roofs The house is built on elevated ground or on stilts, and the main entrance of the house connects to the roads or canals depending on the location of the houses (VAA 2002) 54 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Elevation Section Floor plan Roof plan Figure 37. "Xếp đọi" typology  Source: Vu (2004) and VAA (2002)  These traditional housing typologies provide an understanding of organization of spaces and characteristics of houses in the Mekong Delta The organization of ancillary spaces to the main spaces and the roofs make the different typologies Ancillary spaces are organized at the side ("Chữ đinh" and "Bát dần" typologies) or the back of the main spaces ("Xếp đọi", "Ba gian", and "Thảo bạt" typologies "Ba gian" and "Bát dần" typologies have one large roof, "Chữ đinh" has two perpendicular roofs and "Thảo bạt" has two parallel roofs, while "Xếp đọi" may have several parallel roofs 55 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Generally, these typologies have one large, functional, and compact architectural space and structure, and are built using available construction technology This makes the houses more efficient, especially in dealing with floods, as compactness and simplicity of the houses make it more manageable and economical to raise the houses’ floors and repair houses after floods Houses in the Mekong Delta’s rural area are still built following these traditional typologies or are combinations of these typologies, with several adaptive changes of spaces and materials for flexibility, efficiency and affordability Research about houses in the Mekong Delta’s deep flooding area is still limited Houses in the Mekong Delta’s deep flooding area include houses built by the people and houses in residential dykes and clusters built by the government 3.1.1 Houses built by the people In the Mekong Delta’s deep flooding area with flood depth over meters, the population is distributed on higher land along the rivers, canals and roads The majority of houses are on stilts, and more than 80 percent of houses are built by temporary materials (VAA 2002) In the flooding season, people are involved in fishing activities (Vu 2004) The construction of houses in the Mekong Delta’s flooding area has been studied, and propositions have been made to improve their serviceability These suggestions include precast concrete and precast steel structures, semi-prefabricated components, houses on stilts, mobile houses, floating houses, houses with hard core, and houses with hard frame and floor (VAA 2002) There were also designs of houses and public buildings in the Mekong Delta’s flooding area by professional 56 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area firms, namely NAGECCO and CDPC (1995) However, there has not been a thorough design guidelines and criteria based on insightful understanding of current adaptation of houses and the environmental challenges These designs also have not considered the future challenges in the studied area This research considers the current adaptation of houses in the studied area in current and future environmental threats, to determine the critical issues that need concern in housing design, especially in the future In terms of settlement planning, Viet Nam Association of Architects (VAA) (2002) proposed the following principles for the Mekong Delta’s deep flooding area First, settlement planning should ensure safety and eliminate damage by floods to human activity and production Second, access to transportation should be convenient Third, there should be easy access to infrastructure and social facilities VAA (2002) also suggested solutions for settlement planning in the studied area First, in the Plain of Reeds, due to low population density, the population can be arranged in lines along canals, dykes, roads, and clusters Second, in the infield area not protected by flood control structures, residential clusters should be located at high-elevation areas or surrounded by a dyke system Each residential cluster accommodates about 200 to 300 households and essential public facilities, and water transport is the predominant type of transportation Third, in deep flooding areas along Tien and Hau rivers, it is necessary to improve current residential lines and clusters to be flood-resistant However, these general principles and recommendations have not addressed the problem of erratic inundation and livelihoods issue 57 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area 3.1.2 Houses built by the government The government’s resettlement program In the Mekong Delta’s flooding area, the government has built residential dykes and clusters to resettle people away from the flooded area Residential dykes are narrow lines of houses arranged along roads, usually also along canals Meanwhile, residential clusters are residential areas with houses, public buildings and facilities such as markets, primary schools, clinics, electricity, piped water, and drainage systems The size of a residential cluster is approximately – ha, with 100 – 200 households (Pham 2007) The aim of the program was to build 1,043 residential clusters for 200 thousand households with the total investment of approximately USD 200 million The program was proposed to begin in 2001 and finish in 2005 (Vo 2007) The government elevated the base of the residential dykes and clusters to a level of 0.5 to meter higher than the flood peak level in 2000 (Vo 2007), then after 30 percent of houses were bought, the government built the infrastructure The government initially built the frame of the houses and then the people added claddings, doors, partitions, and back houses Figure 38 shows the locations of residential dykes and clusters in Dong Thap Province, including the studied area 58 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Figure 38. Map of location of residential clusters and dykes in Dong Thap Province   Source: Dong Thap Province’s Department of Construction (2008)  Figure 39 presents the site plan of a representative residential cluster in An Giang Province, with blocks of houses and public services Section A illustrates the elevation of the ground, with the road raised to meters and the building site to 4.2 meters to avoid flood water 59 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Figure 39. Plan and section of residential cluster at Nhon Hung Commune, Tinh Bien District, An  Giang Province  Source: Bui (n.d.)    Advantages and disadvantages of resettlement residential dykes and clusters In 2006, only 35 percent of the program’s households were relocated (Vo 2007) The program has not been accomplished to expectations because the quality of infrastructure and housing conditions are poor and livelihood conditions are not as supportive as before Public services including schools, kindergartens, clinics, and markets were not built completely Many residential clusters lack drainage and clean water supply systems, and some even not have electricity and roads 60 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area According to a survey conducted in two communes, Vinh Hoa and Tan An in Tan Chau District by Pham (2007), only 55 percent of households used clean water and 14 percent of households had usable semi septic toilets Foundations of houses were built from sand or clay, raising concerns on the failure of building foundation and building collapse in strong winds (Fforde et al 2003) In addition, part of the construction was done by the people and they lacked the financial resources, hence the quality of houses was correspondingly low (Phan 2004) Moreover, people’s livelihood activities were negatively affected Research on two communes Vinh Hoa and Tan An revealed that job opportunities and total working days of people living in residential clusters were reduced after resettlement, with 89 percent of households finding it difficult to find jobs (Pham 2007) The survey of Vo (2007) showed that the average income per household of people living in studied residential cluster was VND 0.8 million lower than average income of people living outside After moving to residential clusters, many people sell their land In residential clusters, raising husbandry is banned though majority of households did it before Living in residential clusters causes change in structure of employment and sources of income While income from non-agricultural activities has increased, that from agricultural activities has decreased considerably In general, there are less job opportunities and the distance of travelling to work increases, while they have to pay higher expenditures on services such as water and electricity that they did not have to pay before (Vo 2003) On the other hand, there are several advantages living in residential clusters First, people are safe from the floods and landslides Second, to a certain extent, people have better access to public services such as clean water, electricity, 61 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area education and healthcare Rates of children attending school increase significantly (Vo 2007) According to Fforde et al (2003), the interviewed households think that houses in the residential clusters and dykes are more durable and spacious than their previous houses in the flooded areas Recommendations Phan (2004) proposed that houses should be assigned to real estate companies and they should finish building the infrastructure and houses in good condition before selling to people, to improve the quality of life in residential dykes and clusters However, in this case, their price may increase considerably, making houses unaffordable to the poor Vo (2007) suggested that there should be improvement in design, implementation and monitoring of the resettlement housing projects Commune authority and households should have participation in this process, to customize houses to real needs of the people, and ensure the construction quality (Vo 2007; Fforde et al 2003) Households should be provided with three minimum facilities, including clean water, usable semi septic toilets and electricity (Fforde et al 2003) In addition, resettlement should be linked with measures to offer new jobs and social programs such as rural poverty alleviation, traditional “trade village” development, and works for rural youth (Vo 2007) It is necessary to improve conditions for livelihoods in residential clusters and dykes by creating diverse economic activities such as handicraft production, garden cultivation, and integrated farming fishing system (Garden - Pond - Coops) (Fforde et al 2003; Phan 2004) It would be also necessary to revise the financial support policy, as many people are unable to pay loans even with the subsidized price of houses (Vo 2007) 62 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area In summary, while there have been several in-depth studies on the benefits and problems of resettlement in residential dykes and clusters by the government, there have not been thorough studies of houses built by the people in the Mekong Delta’s deep flooding area In the short term, it is necessary to improve the resettlement residential dykes and clusters in specific issues of infrastructure and services, the quality of construction, and livelihoods In the longer term, attempts should be made to combine local traditional wisdom and expertise to improve houses built by the people and by the government 3.2 Land use planning 3.2.1 Master plan of the Mekong Delta for 2020 by SIUP‐South (2008) In the SIUP-South (2008) master plan of the Mekong Delta for 2020, the Mekong Delta was to be a coastal and riverine agricultural region (Marchand, Dam & Bucx 2011) The planning model consisted of the core cities area and corridors developed along main axis such as the North-South corridor, East-West corridor, border corridor and West Coast corridor (Figure 40) The core cities include Can Tho, Vinh Long, Cao Lanh, Long Xuyen, Rach Gia, in which Can Tho city is the center of this core The core cities develop medium and large industrial zones The economic development of the Mekong Delta will be centered on these core cities and the interconnecting corridors with other cities in the area (SIUP-South 2008) Figure 41 shows that the studied area is mainly rural agricultural area with a provincial town (Hong Ngu Town) It consists of a part of the border corridor and connects to the core of cities through the corridors along Tien River (Figure 40) 63 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Figure 40. The Mekong Delta master plan for 2020 – model of core cities area and multi‐corridors  Source: SIUP‐South (2008)  Figure 41. Map of Spatial Development Orientation in the Mekong Delta to 2020   Source: Marchand, Dam and Bucx (2011)  64 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area The municipal network, which is determined by the water network, is connected by national and regional highways and waterways However, the current master plan for 2020 by SIUP-South has not considered effects of upstream development and new challenges of climate change, including sea level rise There are also contentious issues concerning development For example, industrial zones have been and are planned on first class agricultural land along Tien and Hau rivers, but currently only 30 to 40 percent of the industrial zones are utilized (Marchand, Dam and Bucx 2011) The reason for the random development of the industrial zones in the Mekong Delta is the competition between provinces and cities to attract industry for their economic growth (Marchand, Dam and Bucx 2011) In addition, the co-location of pollutive sources in industry with agricultural land is also a problem The area may suffer from pollution because the master plan has not considered water management between industry, agriculture, and domestic use (Figure 42) and there is a lack of drainage systems 65 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Figure 42. Diagram of relationship among urban, residential, industrial and agricultural areas by  the year 2020  Source: Combined by the Author, using diagrams of SIUP‐South (2008)  3.1.2 Flood control planning by SIWRP (1998b) While the master plan was developed by SIUP-South, flood control planning was conducted by SIWRP (1998b) The strategy of this plan was “Living with the 66 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area floods” with flood control to a certain extent, to eliminate damages and utilize benefits of Mekong Delta’s seasonal floods Measures of flood control planning and their impacts in the studied area are discussed in Section 4.1 To (2002) and Gupta (2005) studied possibilities for integrated water resources management in the Mekong River Basin The research stressed cooperation of the whole river basin and coordination of all fields including sustainable development, utilization, management and conservation of water and related natural resources In fact, there have been numerous efforts by the Mekong River Commission (MRC) to enhance cooperation of countries in the Mekong River Basin However, China and Myanmar did not join the MRC but became its Dialogue Partners The future of the River is still uncertain as China has planned and built its hydropower dams The first dam on the mainstream Mekong River (Manwan Dam) was officially completed in 1996, followed by the completion of Dazhaoshan and Jinghong dams in 2003 and 2010 respectively Therefore, for the Mekong Delta, which would be affected most heavily by upstream development, there is a need to consider possible changes and enhance its adaptive capacity to cope with uncertainties and more extreme conditions in the future In conclusion, the master plan for 2020 by SIUP-South proposed orientation for land use planning in the Mekong Delta, but it has not considered critical challenges such as change of hydrology and climate and water management between industry, agriculture and domestic use To deal with floods, flood control planning was independently proposed and implemented by a different institute – SIWRP (Refer to Section 4.1 for details of flood control planning and infrastructure) The 67 Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area limitation of the master plan is further discussed in Section 5.2.1 and an approach for land use planning is proposed in Section 5.4.1 68 ... Overview of thesis This thesis studies the adaptation of land use and houses in the Mekong Delta’s deep flooding area First, it examines the adaptation of land use and houses in the current context and. .. Adaptation of land use and houses in the upper Mekong Delta’s deep flooding area Flooding has been the most critical issue in the Mekong Delta The upper part of Mekong Delta’s deep flooding area, ... and land use in the studied area Chapter examines current adaptation strategies of land use and houses to floods in the studied area by reviewing the literature about land use and houses in the