Disaster resilient houses : Approach towards ood resilient communities, Majuli, Assam Presented to the Institute of Design, Environment and Architecture, Indus University In partial fulďŹ llment of the Requirement for the degree of Bachelors of Architecture By: Parth Champaneri Thesis guide: Rushank Mehta August 2018
Rancharda, Thaltej, Ahmedabad, Gujarat 382115
Approval of successful completion of B. Arch Thesis The following Bachelor of Architecture Thesis is hereby approved as credible work on the approved subject carried out and presented in a manner suďŹƒciently satisfactorily to warrant its acceptance as a prerequisite to the Bachelor in Architecture for which it has been submitted. It is also to be understood that by this approval, the undersigned does not necessarily endorse and approve any statement made, opinion expressed or conclusion drawn therein, but approves the study only for the purpose for which it has been submitted and satisďŹ es him to the requirement laid down by the thesis committee in July 2018.
Thesis Title: Disaster resilient houses : Approach towards ood resilient communities, Majuli, Assam
Name and Signature of Student:
Name and Signature of HOD:
Parth Champaneri
Bhanupratap Sharma
Name and Signature of Thesis Guide:
Rushank Mehta
Rancharda, Thaltej, Ahmedabad, Gujarat 382115
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ABSTRACT
ACKNOWLEDGEMENT
Majuli district of Assam is exposed to river bank erosion and flood because of various hydro meteorological and topographical characteristics of the basin in which it is situated. Brahmaputra River changes its course over the period of time creates more problems in the livelihood.
I take this opportunity to thank my guide, Prof. Rushank Mehta, for his able guidance in keeping me focused in my approach. I could not have imagined having a better advisor and mentor for my study. I would like to extend my thanks to Prof. Sankalpa, Mangesh, Vickey and Naitik for their valuable suggestions to clear my doubts and helping me to enhance my knowledge.
These hazards create threat to local people who are living along the river resulting in losing of residential and agricultural land. Locals are struggling to cope up with the changing climatic conditions. People are finding new solutions in order to survive to extreme situations. The wave of adapting modern materials and techniques is deteriorating the traditional knowledge. The research comprises of the study done on the overall socio-economic impact of the river bank erosion and flood on local populace. This thesis focuses on learning the vernacular techniques and to apply that knowledge to suggest possible solutions.
I am grateful to my family and friends all the people who helped me throughout to complete my thesis. The people of Majuli deserve a special mention, I am deeply grateful to the people of Majuli River Island for sharing their life stories and extending their generous hospitality to me throughout this study, Thank you Manjeet for hosting me, Mr. Pradip Deka and Chitranjan for showing interest in my work and helping me in Majuli. In Majuli, I am also thankful to many local intellectuals and representatives of several organizations. I cannot go without thanking my friends who gave me their immense support and encouragement through the process of the study. I thank Saloni and Drashta for being there always. I also thank my friends Smit, Neel, Priyanka, Nimmi, Poojan and Rana for helping me out whenever I needed. I will never be able to fully repay the debts that have made this possible: The love, care, friendship, mentoring, critical engagements, and generosity that so many people have extended to me during the time of these five years. Thank you.
DEDICATED TO,
THE FLOOD AFFECTED PEOPLE OF NORTH EAST INDIA
TABLE OF CONTENT
CHAPTER SUMMERY CHAPTER 4
CHAPTER 1 1.1 Aims and Objectives 1.2 Scope and Limitations 1.3 Approach and Methodology 1.4 Methodology chart
01 01 02 05
CHAPTER 2 2.1 Introduction 2.2 Current problems 2.2.1 Impact of flood and erosion on the people of Majuli 2.2.2 S.W.O.C analysis 2.3 Understanding the project 2.3.1 What is Flood? 2.3.2 What is a scientific definition? 2.3.3 What does “Flood Resilient” means? 2.3.4 What does “Flood Proofing” means? 2.4 Types of Floods
09 10 11 13 15 15 16 16 16 18
53 54 57 59 60 81 83 85 87 89
CHAPTER 5 5.1 Design Development 5.1.1 Drawings 5.1.2 Model photos
91 98
CHAPTER 6
CHAPTER 3 3.1 Introduction to the study area 3.2 Assam and Flood 3.2.1 Factors of flood incidence in Assam 3.3 Census Data 3.4 Hazard Maps 3.5 Traditional Houses of Assam 3.5.1 “Wattle and Daub” house 3.5.2 “Ikra” house 3.5.3 “Chang” house 3.6 Traditional architecture in North-East India 3.6.1 “Hill Tiwa” house 3.6.2 “Karbi” house 3.6.3 “Mishing” type house 3.7 Literature review - “Flood Disaster Management” 3.8 Bamboo connections
4.1 Study area 4.1.1 Isolated and stranded 4.2 People, Environment and Comminities 4.3 Traditional craft of the people 4.4 Field visit 4.5 Case studies 4.5.1 Bambu social 4.5.3 Black bamboo community center 4.5.5 Mokoko floating school 4.5.4 Panyaden school 4.5.5 Temporary dormitories
23 24 25 27 29 32 32 33 35 37 39 41 47
6.1 Questionnaires 6.1.1 Household questionnaires 6.1.2 Questionnaires for the Architects 6.1.3 Questionnaires for the local Contractors 6.2 Interviews
101 103 104 105
Bibliography List of Figures
106 108
CHAPTER SUMMARY Chapter 1: Introduction In this chapter, brief notes are included. Study about the initiation of the research along with the need of the study has been described. The Aim, Objectives, Methodology has been described in detail. Chapter 2: Introduction to Topic This chapter talks about the study area. Detailed literature review has been done to understand the scenario of the people in Majuli. Basic concept of the study is described. Different case studies have been shown in details. Chapter 3: Introduction to study area In this chapter detailed analysis of how flood affects people of Assam is done. This also includes Census data and Hazard maps to understand various aspects. The different houses of North-East India are also included here. Chapter 4: Site studies This gives an idea about the study area and the context and criteria for selecting particular area. Various aspect of the region ranging from culture to the people of the region is covered in the area, also includes different houses and construction techniques people are using. Analysis of existing house forms and area is done. Chapter 5: Design development This chapter includes all the presentation drawings and model photos. Chapter 6: Annexures This chapter covers the Questionnaires and Interviews that is conducted during the site visit.
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CHAPTER 1
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1.1 AIMS AND OBJECTIVES AIM This thesis will explore/study flood resilient housing, trying to answer the demand for new development which does not harm the environment and natural resources. It will also help to raise the awareness in the public. The intent of this project is to design a community housing for displaced families of the flood prone areas in Majuli, which would have the ability to survive natural disasters.
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LIMITATIONS The project will be restricted to Majuli region or locality only. The assessment of other calamities will have certain limitations in the final outcome in terms of seismic loads, cyclone impact load calculation. (Earthquake and cyclone will be considered while designing but will have certain limitations.) The study and development will be restricted to addressing issues at micro level, the level at which it makes a direct impact on the local populace.
OBJECTIVES
1.3 APPROACH AND METHODOLOGY
To understand the ways to increase resistance of the built-form, specifically dwellings from flood and earthquake. To understand the impact of the design changes in terms of change in local lifestyle. Study the changes in housing typologies due to flood resistance. Understand various strategies employed by locals for increasing resistance to natural hazards Increase the use of local materials and techniques to increase hazard resistance of the houses
The collection of secondary information has been done from various government and private institution to understand flood situation in Majuli and understanding different factors affecting built forms.
1.2 SCOPE AND LIMITATIONS SCOPE To study is to identify different villages prone to flood and erosion. The study will focus on housing and resilient techniques used in vernacular house forms in Majuli. The development of housing community by incorporating different modern materials. To suggest the recommendation to the dwellings for ensuring the self-sustainable and resilient housing. To develop a people centred approach to housing, with less intervention of state, contractors, professionals and developers.
Study of typologies of vernacular housing in Assam (parts of Majuli island) is carried out and also to find the different strategies to withstand the flood. The findings will be incorporated in the final outcome which will be the community housing for the people. Initial stage includes site studies and vernacular housing study of Majuli area. The study will also focus on the materials and the details. Further to explore different strategies by incorporating the new materials to withstand the flood and to come up with the design for a prototype of community housing for the disaster prone riverine island of Majuli. To prepare appropriate housing solutions based on selected sites and specific conditions.
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SELECTION OF STUDY AREA
VILLAGE SELECTION
Assam is selected as a study area based on two factors. Firstly, it is known for the rich culture and diversity. The use of primitive materials in house forms and there is substantial area to research upon. Secondly, the impacts of natural hazards are at a great extent. Assam is a land where different communities and tribes have lived together and created symbiotic adaptation with nature.
Majuli has more than 160 villages. The selection criteria for villages are based on flood prone zone in Island. According to flood prone zones three different villages which have three different flood estimation levels are selected for study. These Villages also had particular tribe living there for many years. i.e Mishing village, Kumar Village who are associated with different occupations.
In Assam, There are many flood prone zones including Morigaon, Dhemaji, Lakhimpur, Nagaon and Majuli based on the study done on GIS and ASDMA report. Majuli district is selected as a study area because of its cultural diversity and it is surrounded by Brahmaputra River. Majuli is the biggest riverine island in the world. Changing course of Brahmaputra River created livelihood more vulnerable.
Data Analysis:
DATA COLLECTION
At the end of the data collection process, the data collected was analysed to understand the topic in depth. Conclusion and Recommendation: After the completion of all above mentioned stages, conclusions and design proposal is given in drawing format.
The process of data collection is done at two levels. i.e. Secondary level and primary level. Secondary Sources of Data: Statistics and Economic Department, Guwahati Water resource department, Jorhat National disaster management authority, Guwahati Census of India Department, Assam Tourism Department of Assam Office of water resource, Majuli Kamlabari Tribal Architecture in North-East India, Rene Kolkman Primary Data collection: Stakeholders: Local People in targeted areas NGO workers Guides Monks in satras Government officers Methods of data collection: Primary Survey Questionnaires Audio, Video recordings Photo documentation Measure Drawing of each house Key person Interview Observations
This chart (Fig1.1) is showing the methodology, it has three different parts (I) Pre field visit includes Initiating the research/thesis topic. Study based on secondary sources (II) During field visit includes the study conducted on five villages Kamlabari, Dhakinpat, Salmora, Chitadar suk and Garmur. It also includes discussions with ASDMA (Assam State Disaster Management Authority, Guwahati.) Water resource department, Majuli. And Field surveys including documentation and questionnaires. (III) After field visit includes the inferences of site studies, Case study analysis, Initiation of conceptual strategies into design.
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1.4 METHODOLOGY CHART
Fig. 1.1 Methodology Chart
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2.1 INTRODUCTION
2.2 CURRENT PROBLEMS
People are vanishing from villages moving towards cities, with loss of cultural dwellings and the belongings of their ancestors. The urge to move out from native place looking for the better future and the opportunities created the imbalance to traditional and vernacular dwellings.
Flood and River bank erosion are dynamic and natural processes which have huge impact on livelihood as homesteads are destroyed, Cultivatable lands are wiped out and employment opportunities are reduced. The extensive flood on the island has changed their socio economic status and have adapted and coped with the new environmental change in the riverine areas of the Majuli district.
Sometimes nature’s procrustean approach towards the living, forces people to abandoned the place/area. In the process of adapting the new surroundings, the traditional/vernacular part is sometimes forgotten. In the case of Assam, natural calamities like flood, erosion and earthquake made substantial changes to the lives of Assamese people. People have left their homes as these calamities become frequent and uncontrollable. Instead of leaving the place, can we not learn the vernacular techniques / strategies that people have been following from primitive times and apply the same knowledge to create housing or a community which will withstand all the calamities like flood, erosion and earthquake? Can we not create the community which will be self-reliant?
The major cause of destruction during flood or earthquake is related to structural stability of the building. Since the materials used in Assam vernacular style are light weight, hence they have flexibility to sway with the horizontal motion during the floods and have lesser chance to damage. But, it can’t be applied in an urban context so that techniques need to be explored and adopted to modern context with technological inclusions.
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2.2.1 IMPACT OF FLOOD AND EROSION ON THE MAJULI PEOPLE Displacement:
The severe impact of flood and erosion and the loss of homestead make people more vulnerable. Displacement is the immediate impact of flood and erosion. For better livelihood the displaced people usually moved to nearby areas, migration to distance places are so common.
Loss of agriculture land and home:
Loss of agriculture land and home is a very common effect of flood and siltation destroys a vast land of cultivation. Farmer can cultivate only two to three crops in a calendar year with subsistence homestead gardening.
Psychological effect:
The loss of agricultural land and human life creates financial burden and cause emotional hardship.
Poor transport system:
As the areas are frequently affected by flood and siltation, the road networks are not well developed, and since this is an island the only way to reach there is by a ferry.
Problem of education:
The inundation and destruction of school buildings by flood and siltation are annual phenomenon. Due to these problem irregularities in the classes, scarcity of essential infrastructure etc. hampers the education system.
During the floods, people shift to higher areas, which are limited. Due to high population concentration they face problem of health and hygiene. Mosquitos carry many diseases. Various waterborne diseases like malaria, dengue, skin dieses etc. are very common among the villages. Affected areas do not get adequate medical facilities, sometimes primary medical center are also affected by these natural disasters.
Fig. 2.1 Socio Economic factors
Medical problem:
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2.2.2 SWOC ANALYSIS The diagram of SWOC (Strength, Weaknesses, Opportunity, Challenges) is showing different aspects of this project.
• • • • • • • •
Cultural believes and community engagements People’s beliefs / people they follow/ religion / culture Agricultural land / fertilised land because of flooding Fishing / Water transport Local tourist attraction / UNESCO world heritage site proposal World’s biggest riverine island Flora and Fauna / Biodiversity Community have the organisation like NDMA, ASDMA for relief measures
• • • • • • •
People willing to evacuate early People do not easily adapt to the new environment People face traumatic effects of disaster Low income group Loss of agricultural land/livestock Forgotten traditional techniques/knowledge Networking and information sharing on disaster management
• • • • • •
The three different sites have three different flood estimation levels. Fertilized land/ more agricultural opportunity Using the floating garden during the flood times They can do fishing during the flood timing Education opportunity / Study of flood mitigation Abundant natural resources and a fertile soil due to eruption
• • • • •
Eruption/Erosion becomes frequent is sometimes inevitable Flood water level / Inundation is higher to stop Life during the flood Livestock at danger Effect of medical problems
Fig. 2.2 Majuli people and activities
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2.3 UNDERSTANDING THE PROJECT Water is one of the primordial elements in the survival of human being. Water creates problem whether in the presence or in absence. It can be categorised mainly into two parts, where surplus of water causes flood and shortage of water causes drought. In both the situation people have to face many difficulties. Assam is situated at the eastern most part of India; it faces a huge amount of losses due to devastating flood caused by the river Brahmaputra. The losses are more in Morigaon, Dhemaji, Majuli, North Lakhimpur, Dhakuakhana and a few more places in Barak valley in Assam. The problem of flooding in Assam is very old and solution is very much difficult due to complex and devastating nature of the river Brahmaputra. Both the short term and long term measures are sometimes failed to mitigate the losses caused by flood.
2.3.1 What is flood? Flood is a situation where the water is higher than the regular level, when it creates unusual situation. Flood is defined as an overflowing or influx of water beyond its normal defines exp. Over land: Inundation -Oxford dictionary – 1990 Floods are also social disasters, which affect the poor/ rich both. Disaster makes the poor more vulnerable to the next and converts disasters into a disaster process.
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2.3.2 What is a scientific definition? Flood in the valley of a river is an important hydrologic and geomorphic events dominated by two distinctive characteristics.(I) it represents a significantly high discharge as compared to the mean flow. (II) High magnitude flood events are outcome of random and anomalous synoptic conditions and cannot be predicted. For meteorological studies a flood is considered severe if the highest flood level is at least 2m above the danger level. (*FLOOD AND BANK EROSION PROBLEMS OF THE RIVER BRAHMAPUTRA, ASSAM) (Ramaswamy 1985)
Definitions: Disaster - A serious disruption of the function of a community causing widespread human, materials or environmental loss, which exceed the ability of the affected community to cope using its own resources. Hazard – Event or occurrence that has potential for causing injuring or death or damage to property or the environment.
2.3.3 What does “flood resistance” mean for built form? Floodplain areas can be subjected to hydrostatic (standing water) and hydrodynamic (flowing water) pressures during floods. For buildings, these pressures can result in displaced foundation, walls, collapsed structures, floating tanks and other damage. Flood resistance thus requires that structural and nonstructural components be durable, resistant to flood forces including buoyancy, and resist to deterioration caused by inundation with flood water.
2.3.4 What does “flood proofing” means? Flood proofing is to make a particular building strong enough to withstand the flood. That can be done in various ways that includes changes in the existing structure either by making it at a higher level to avoid the contact of water or to make the structure rigid enough to reduce any potential damage done by flood waters.
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Flood proofing can be subdivided into several categories: Dry-flood proofing: This requires use of special sealants, coatings, components and/or equipment to render the lower portion of a building watertight and substantially impermeable to the passage of water. Wet-flood proofing: This allows the uninhabited lower portion of a building to flood, but uses materials that will not be damaged by flooding.
Active flood proofing: Active flood proofing known as contingent (partial) or emergency (temporary) flood proofing, requires human intervention to implement actions that will protect a building and its contents from flooding. Successful use of this technique requires ample warning time to mobilize people and equipment and flood proofing materials.
Passive flood proofing: Sometimes referred to as permanent flood proofing, requires no human intervention. The building is designed and constructed to be flood proof without human intervention. (*https://www.wbdg.org/resources/flood-resistancebuilding-envelope)
Fig. 2.3 load transfer diagram
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2.4 TYPES OF FLOODS The study of the types of flood is conducted in order to understand the different impact of flooding. There are mainly five types of flooding which can be defined depending on the cause of flooding. 1. Flash floods 2. Coastal floods 3. Urban floods 4. River floods 5. Pluvial floods
Flash floods: In areas with steep slopes, heavy rain can cause a riverbed that held very little or no water at first, to suddenly brim with fast flowing water. The rain water is collected on the slopes, then flows downhill gathering speed and all the water comes together in the river bed. The water level rises fast. The water flows over the river banks and floods the area. It all happens fast, it rains heavily. The water flows at high speed. Because of this speed it has the strength to carry away heavy objects. A flash flood is a very direct response to rainfall with a very high intensity or sudden massive melting of snow. The area covered by water in a flash flood is relatively small compared to other types of floods. The amount of water that covers the land is usually not very large, but is so concentrated on a small area that it can raise very high.
Coastal floods: Coastal flood is when the coast is flooded by the sea. The cause of such a surge is a severe storm. The storm wind pushes the water up and creates high waves. A flood starts when waves move inland on an undefended coast or overtop or breach the coastal defence works like dunes and dikes. The waves attack the shore time and again. When it is a sandy coast, each wave in a storm will take sand away. Urban floods: Urban flooding is specific in the fact that the cause is a lack of drainage in an urban area. As there is little open soil that can be used for water storage nearly all the precipitation needs to be transport to surface water or the sewage system.
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High intensity rainfall can cause flooding when the city sewage system and draining canals do not have the necessary capacity to drain away the amounts of rain that are falling. Water may even enter the sewage system in one place and then get deposited somewhere else in the city on the streets. Sometimes you see dancing drain covers.
River floods: Rainfall over an extended period and an extended area can cause major rivers to overflow their banks. The water can cover enormous areas. Downstream areas may be affected, even when they didn’t receive much rain themselves. With large rivers the process is relatively slow. The rain water enters the river in many ways. Some rain will fall into the river directly, but that alone doesn’t make the river rise high. A lot of rain water will run off the surface when the soil is saturated or hard. It will flow to small rivers that flow to larger rivers and these rivers flow into even larger rivers. In this way all the rain that fell in a large area (catchment area) comes together in this one very large river. When there is a lot of rain over a long period, you see the river rise gradually as it is fed with water form smaller rivers.
Pluvial floods: Ponding is a type of flooding that can happen in relatively flat areas. Rain water falling in an area is normally stored in the ground, in canals or lakes, or is drained away, or pumped out. When more rainwater enters a water system than can be stored, or can leave the system, flooding occurs. In this case, rain is the source of the flood: not water coming from a river, but water on its way to the river. That’s why it is also called “pluvial flood”. (*http://eschooltoday.com/natural-disasters/floods/ types-of-floods.html)
Fig. 2.4
Fig. 2.5
Fig. 2.6
Fig. 2.7
Fig. 2.8
CHAPTER 3
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3.1 INTRODUCTION TO THE STUDY AREA
3.2 ASSAM AND FLOOD
The study area selected for thesis is Assam. Assam serves as a major gateway to the north-eastern corner of India. It shares borders with the countries of Bhutan and Bangladesh and is surrounded by the states of Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura and Meghalaya, which together with Assam, are called the Seven Sister States of the country. To the east of Assam lay Arunachal Pradesh, Nagaland and Manipur, to the west lay Bangladesh and Tripura, whereas Mizoram and Meghalaya lay to the south of Assam.
Assam is situated in a high rainfall area with an average annual rainfall of 2,546 mm. About 60-70 per cent of the monsoon rain is received within a span of 3-4 months during May to August. Because of high rainfall in the state and upper its neighbouring areas, The Brahmputra and Barak, the main two rivers causes major problems in the form of flood, erosion and drainage congestion in the plain districts. The recurring floods have extensively damaged the rural economy of the state, with accounts of extensive sand casting of once-fertile lands especially on the North Bank of Brahmputra, as well as river bank erosion throughout the state, forcing rural families to migrate to towns.
The state is rich in water resources and has vast tracts of fertile land. Assam is also the third-largest producer of petroleum and natural gas in the country and has ample reserves of limestone. With its five national parks and 18 wildlife sanctuaries, the state is a biodiversity hotspot. Other potential areas of investment include power and energy, mineral-based industries, tourism and crude oil refining. (* www.ibef.org/states/assam.aspx)
The occurrence of multiple waves of flood during the monsoon period extensively damage crops, kills livestock and brings untold misery to the people. The number of people affected and the amount of damage have increased steadily over time. The National Flood Commission had estimated the area vulnerable to floods in Assam at 31.06 Lakh hectares against 335.16 Lakh hectares for India. Assam, given the extensive size of its plains and flanked by hills on either side of both the rivers, is the most floodprone state of the region. It accounts for 9.4 per cent of India’s total flood prone area. Based on the incidence and extent of flood the state is categorised into two broad areas: chronically flood affected and occasionally flood affected. (*https://britannica.com/place/Assam)
Fig. 3.1
Fig. 3.2
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3.2.1 FACTORS OF FLOOD INCIDENCE IN ASSAM The floods in Brahmaputra basin and particularly in Assam are caused due to a variety of factors. The flood can broadly divided as, 1. Meteorological factors 2. Geomorphic factors 3. Hydrologic and anthropogenic factors Flood affects many ways in the lifestyle of Assamese people. Many floods are generated by rainstorms. The geomorphic cause includes meander growth, channel migration and failure of landslides induced dams. Anthropogenic floods are caused by failure of manmade dams and breaching of artificial embankment. The geographical setting of the place surrounded by eastern Himalayas, A very high rainfall regime, annual rainfall varies from 100cm to 400cm in the basin but most of the rainfall falls during the monsoon season from June to September. Fragile geographical formations of the region cause heavy erosion. Major earthquake happens after every 30 years. 400 shocks happened in a period of 1920 to 1969. The earthquakes result in enormous quantities of silt and debris washed into the plains and thus rising of riverbeds.
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Brahmaputra was aimed at protection of the riverside villagers from annual devastating flood and subsequent intensive river bank erosion sixty years back. During the process of making embankment more than ten thousand families were displaced from their paternal acre and till today many of these displaced families living on the embankment without having any compensation from the authority. The embankment could serve its purpose next thirty years of its construction but by this time the embankment caused permanent deterioration in the river character, the sand and silt load entrapped in between these two embankments -along right and left banks of the river lead to deposition of sediment in the river corridor which raised the river bed to an alarming extent and the earlier meandering character of the river changed into braided character. Thus the over-topping of flood water, frequent breach in the embankment, river bank erosion etc. become a regular phenomenon for the river Brahmaputra. The flood due to river Brahmaputra as a result of these complications becomes more devastating and erratic in nature. The recurring flood, erosion, sand deposition, and displacement these entire make several thousands of families more vulnerable. Government is taking steps to reduce the erosion by building embankment, using porcupines and geo-bags. (*The Flood Situation of Assam – A Case Study)
Fig. 3.3
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Chart B
3.3 CENSUS DATA Census data shows the materials that they use for the roof, floor and walls. According to the census data of 2011 it is observed that there is a vast difference in materials used for buildings in rural areas as compared to urban areas. The study of two different areas is studied in order to understand the material availability in villages as compared to cities. Chart A is showing the materials used in floor in urban areas and in rural areas. Chart B is showing the materials used in making roof in urban areas and in rural areas. Chart C is showing the materials used in making walls in urban areas and in rural areas.
Fig. 3.5
Chart a
*Data is collected from census data of india 2011, Graphics are generated by the Author
Chart c
Fig. 3.4
Fig. 3.6
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3.4 HAZARD MAPS Natural hazards are very frequent in Assam. To understand what are the hazard zones in Assam these maps are studied. It shows the areas where hazards are frequent and what areas are vulnerable.
Fig. 3.9
This map is showing total expected average annual population explosed to flood.
Fig. 3.7
This map is showing the earthquake zones in Assam.
Fig. 3.10
Overall super-imposed map shows the zones which are very prone to natural calamaties. Which includes Morigaon, Nagaon, Dhemaji and Majuli districts. (*UNEP/DEWA/GRID_Europe,TARU Analysis,2011)
Fig. 3.8
This map is showing fire prone zones in Assam.
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3.5 TRADITIONAL HOUSES OF ASSAM
3.5.1 Wattle and daub house
There are many distinct architectural features are seen in North East states, which differ by climate, culture and traditions. They evolved in course of time and were majorly built by the inhabitants themselves, without any formal training in construction. These houses, built with locally available materials, were sensitive to the existing environment and took into consideration the constraints imposed by the climate. Architectural typologies have developed in the North East as factors of tradition, climate and functionality. The materials used are locally available materials like bamboo, cane, cane leaves, mud, and lime. Stone chips, rock slabs, etc. are also being used. Sloping roofs are a common architectural feature in all the architectural typologies because of high rainfall in the North East. According to the materials used and the type of construction, the traditional houses of North East India can be broadly classified as three main categories.
Fig. 3.11 Wattle and Daub house
These houses are essentially made from organic renewable resources such as bamboo, mud, grass, straw, cane leaves, cane etc. The plinth and the foundation consists of consolidated earth with timber or bamboo posts, the walls consist of bamboo mats, split bamboo framing, grass, earth, cane leaves etc., and the roof is thatched, made of wheat or maize straws, with split bamboo framing.In this housing system bamboo is used for the main structural member. The wall is made of bamboo strips and it’s plastered with mud or mud mixed with dung. Nowadays, a brick wall is raised up till 1 M from the plinth to support the wattle and daub panels and also to resist the flood / flowing of water. The plinth is made of rammed earth and the foundation of consolidated earth with timber and bamboo posts. Construction materials are wood and bamboo posts and horizontal members with wall infill of bamboo split size between 15-40 mm. Mud plaster with a mixture of cow dung is generally applied over the walls. And roof is made up of locally available reed and sometimes they use G.I sheets as well, depends on the economic factor.
3.5.2 Ikra house
Fig. 3.12 Ikra house
The Ikra houses are usually single dwelling unit and don’t share walls with adjacent building. Locally available reed is called Ikra, thus this houses are called Ikra houses. This house is made using wood based materials, its performance during earthquake is good and made out of lightweight materials. Ikra reed Bamboo Mud for walls Flexible connections are used between wooden elements at various levels. The wall panels are made of bamboo frames in filled with shoot of Ikra reed oriented in the vertical direction. Then it is plastered both the sides with mud-dung mixture and painted with lime. The roof is pitched with a high gable to cater a heavy rainfall in this region. These houses are generally built on flat-sloped terrain with L-C shaped plan.
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3.5.3 Chang house
3.6 TRADITIONAL NORTH EAST INDIA
The major components of the houses are bamboo, cane and palm leaves for roofing. Bamboo is widely used for column, lintel, flooring, roof, framing, openings, etc. The house on raised stilts is an age old structures which was originated around the Himalayan ranges. It is a big linear hall with a central kitchen for a joint family. The lower part of house is used to provide shelter to animals that every house-holds rears, boats for the riverside village and also for the protection against the wild animals and also to level the house in case of undulated land. Earlier people used bamboo columns which were easily damaged in water currents. The stilted houses are generally rectangular in shape and are similar to bamboo Kutchha houses with linear planning and rooms opening into each other. These houses are constructed over bamboo posts and bamboo diagonal bracings are tied to form the stilt areas. The structure above is formed by horizontal members tied across the bamboo posts with jute ropes and using dowel joints. The stilt height is typically 1.50 to 2.00 metres from the ground level. The space below the stilt is often used to store a canoe for emergency usage during floods . The stilted houses are typically designed to keep out the effects of heavy monsoon. The floor and walls inlays are mostly bamboo weaves, which allows the water of floods and heavy rains to pass rather than getting stored. The roofs of the houses are made by fixing bamboo trusses over the posts, over which local grass is laid. The roof height from weaved floor is approximately 3.50 metres. A bamboo loft is fixed below the roof inside for secure storage of goods in case of floods. Bamboo being a bad conductor of heat keeps the interiors cool and adequate ventilation through the permeable floors and wall keeps the moisture content inside the house slow. (Hemant Kaushik, 2009)
ARCHITECTURE
IN
The architecture of north-east India responds to their climate, culture and tradition. It has the ability to adapt the changing climatic conditions. The use of primitive material makes it less vulnerable to natural hazards. However because of structural inadequacy and lack of termite safety, the elements of houses don’t last long and needs to be replaced frequently. These are the houses that people built using traditional materials and techniques in different areas in North East India.
Fig. 3.13 Chang house
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3.6.1
(*Base drawings are taken from Tribal architecture in North-East India analysis is done by the author)
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3.6.2
(*Base drawings are taken from Tribal architecture in North-East India analysis is done by the author)
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(*Base drawings are taken from Tribal architecture in North-East India analysis is done by the author)
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3.7 LITERATURE REVIEW FLOOD DISASTER MANAGEMENT BY ARUN KUMAR TALWAR / SATISH JUNEJA Publication: Commonwealth Publishers Publication year: 2009
CHAPTER 1: GLOBAL FLOOD SCENARIO This chapter talks about Global Flood scenario, where human settlements frequently interfering with natural floodplain processes created imbalance in the natural process. It talks about floodplain areas, where floods are more frequent. Riverine flooding where it ranges from narrow contained channels to wide, flat areas. Also different types of flood such as Flash floods, alluvial floods, ice jam flooding, etc.
Flooding and Erosion These are result from storm surge and wave action because of increase in water surface above normal tide waves, results in erosion. Depending upon local topography, storm surge may inundate only a small area or may inundate whole river bank lands. In addition to that wave action is an important aspect, which becomes very destructive, causing damages to natural and manmade structure by hydrodynamic pressure causing damage to nearby areas.
Subsidence Subsidence is a type of ground failure that can lower the ground surface, causing or increasing flood damage in areas of high ground water, tides, storm surges or overbank stream flow. Subsidence is a result of both natural process and human activities.
Liquefaction Liquefaction caused by earthquakes and occurs when seismic shock waves pass through unconsolidated and saturated soil, allowing the soil grains to move freely and pack more closely together.
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CHAPTER 2: COPING WITH FLOOD This chapter talks about how intensity of flood is increased because of the many reason, and how do you take care of that situation before the flood and after the flood. What can you do before the flood? (I) Understanding the flood scenario beforehand (II) Understand the affected area (III) What steps people have taken till now (IV) Situation you will face after the flood
CHAPTER 3: FLOOD MITIGATION Floods are part of natural cycle and provide definite beneficial effects. Floodplains provide fertile lands by providing rich natural resources; flood plains have attracted humankind for centuries. Floods events can also benefit ecosystems by maintaining fish spawning area, helping fish migration and flushing debris, sediment and salt. This chapter mainly talks about how one particular body should manage flood scenario before and after the flood. It also talks about the environmental factors during flood management. These are the important factors in flood. Environmental Climatic conditions: rainfall patterns, temperature, evaporation, radiation, snowmelt. Geophysical conditions: Morphology, conveyance of drainage systems Records of past floods: Magnitude/Hydrograph, frequency and type of floods, sediment loads, inundated area and inundation depths. Future Flooding scenarios: Flood hazard maps under different climatic and socio-economic development scenarios.
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Social Land use patterns, in particular urbanization, deforestation and agricultural practice. Number of people affected by floods Demographic trends, population densities in floodprone areas in the past and in projected models. Vulnerability of population at flood risk including future risk projection due to climate change.
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If the building is located in an area subjected to wave action, such as coastal high hazard area an open foundation is effective to elevate. It also allows water and debris to flow beneath the building and can reduce potential damage.
Economic Economic significance of floodplains Economic impacts of past floods on the various sectors such as agriculture, industry, households and livelihoods, hydropower, navigation, etc.
CHAPTER 4: MEDICOLEGAL WORK IN FLOOD AFFECTED AREAS CHAPTER 5: MANAGEMENT OF DEAD BODIES CHAPTER 6: FLOODPROOFING STRATEGIES Flood proofing decisions must include an assessment of flood and erosion hazards affecting the structure. Elevating a structure so that flood waters are less likely to cause damage is an effective permanent flood proofing technique when erosion is not a concern.
Fig. 3.15 External loads
Wind loads on elevated structures are increased and damage potential is higher when the wind forces occur in combination with flood forces, therefore wind loads must be taken into consideration in the design of elevated buildings. Cost is also an important factor in elevating the structure Wood/Bamboo - Lighter / less costly Masonry - Heavy / More costly Elevating on Piles Due to velocity flow, a flood impact and soil type, elevation on piles is primary technique used in high hazard areas. Piles must be either wedged into bedrock or driven deeply enough that there is sufficient friction between pile and surrounding soil to transfer the loads acting on the building into the surrounding ground. Elevating on Piers Piers are vertical structural member that are supported by footings. This method is less suited to flood hazard zones because that can only transfer load vertically but in case of flood there are hydrostatic and hydrodynamic forces that may apply on structure. Thus piers must be substantial enough to support the structure and resist the lateral forces.
Fig. 3.14 Utilities on the raised structure
Elevation on Posts Elevation on posts has limited applicability in flood prone zones because these areas may be affected by scour or erosion. Posts are made of wood, steel or precast reinforced concrete, earth, gravel or crushed stone is backfilled around the hole once the post is set.
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Elevation on solid foundation walls
Flood prone areas
Elevation on extended solid foundation walls is normally used in areas of low to moderate water depth and velocity. If the footings are not deep and wide enough, they may not be able to resist the additional loads. Hydrostatic forces can result in collapse of the building, to reduce the damage these homes must be constructed with openings that allow flood waters to pass through the walls.
(I) Brahmaputra and Barak river basins Assam, Arunachal Pradesh, Meghalaya, Mizoram, Northern parts of Bengal, Manipur, Sikkim, Tripura and Nagaland (II) Ganga river basin (Yamuna,Sone,Gandak,kosi) Uttaranchal, U.P, Bihar, west Bengal, Haryana, H.P, Rajasthan, M.P and Delhi (III) North-east river basin (Satluj,Ravi,Beas,Jhelum and Ghaggar ) Jammu and Kashmir, Punjab, Haryana, Rajasthan (IV) Central India an Deccan rivers (Narmada,Tapi,Mahandi,Godavari,Krishna) Central and southern India, mainly Orissa
Relocation / Demolition Relocation is appropriate if flood and erosion hazards are such that continued occupation of the building at its present location in unsafe. Cost, in relation to building value, is the major concern associated with relocation/demolition. Elevation techniques structures)
(Applicable
on
existing
(I) Extend the walls of the house upward and raise the lowest floor (II) Convert the existing lower area of the house to non-habitable space and build a new second story for living space. (III) Lift the entire house, with the use of machines and build a new foundation to elevate the house.
CHAPTER 7: RESOLUTIONS ON MANAGING CORPES CHAPTER 8: FLOODS MANAGEMENT IN INDIA India is the most disaster prone countries in the world. About two thirds of the land is vulnerable to natural disasters. Causes of flood The main reason for flooding is overflowing of rivers; the root cause of flood is excessive rainfall. Most of the northern rivers originating from Himalayas cause flooding and erosion in the flood plains.
Beneficial use of flood A mild flood brings with it good amount of fine silt which includes human/animal wastes having rich nutritional values. It increases the land fertility. Ground water also gets recharged, Tanks and ponds gets filled up and becomes useful for fishery as well as for providing irrigation. Flood Management policies (I) Structural measures Embankments Drainage improvement in the area Reservoir (II) Non-structural measures Flood proofing Flood plain zoning Disaster preparedness and response planning Flood rescue and relief Community participation in flood management
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3.8 BAMBOO CONNECTIONS
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Fig. 3.16
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4.1 STUDY AREA
4.1.1 Isolated and stranded
In north east India, in the disaster-prone state of Assam, Majuli Island is surviving for its identity. The world’s largest inhabited river island encompassed by the Brahmputra River. Majuli is at the risk of being swallowed by the Brahmaputra River anytime.
The displaced communities rarely receive government aid for rehabilitation and rebuilding of their houses. Which in spite of being raised on stilts, gets flooded at least once in 3 years, swept away by cyclonic winds, and island itself is located in close proximity to earthquake fault lines. Being isolated from the mainland by the river makes it more vulnerable than other established areas with connectivity to the roads. Transport and communication
The River Brahmaputra divides into two channels – the northern Kherkutia channel and the southern Brahmaputra channel between Dibrugarh and Lakhimpur Districts and both the channels join again about 85 km downstream at Ukhalchuk - forming Majuli, the largest inhabited River Island in the world.
Majuli is surrounded by river from all the sides made this a distinctive place. The region has only one access from Lakhimpur through road which was made in 2015. But that takes 10 hours to reach from the main city hence people prefer to go to island only by taking ferry from Nimati ghat. The government administrative has systematized a ferry service between Jorhat to Majuli through which the daily activity are been carried. These ferry services are used for daily commute as well as to transfer the goods and materials.
The width (in North- South direction) of island varies between 10 Km to 15Km. The Majuli Island is a part of Majuli Revenue Circle. As per the revenue records, the area of Majuli Revenue Circle in the year 1950 was 1245.12 sq-km. It included entire reach of Brahmaputra water body up to left bank along Sibsagar, Jorhat and Golaghat Districts. But as per Survey of India map, the area of Majuli Island was only 733.79 sqkm in the year 1914. The Majuli Island is an administrative Sub-division under Jorhat District. The Island represents a colorful rainbow of cultural integration with 70 % of its population belonging to tribal communities such as Mishing, Deori, Kachari and Koch Rajbongshi. It has a population of 1.68 lakh as per 2011 census. Majuli Island has been under serious attack by the mighty Brahmaputra. Loss of land mass on account of erosion of Brahmaputra River right bank has been regular feature for Majuli Island.
The ferry service is only available for people from 7am to 10pm making it isolated at night. During monsoon every year, the region is flooded and it becomes challenging for the ferries to work. Hence people are focusing on using their own resources for their everyday needs. Every year Brahmputra floods, and erodes the island around it. Changing the direction of flowing it creates erosion in the areas of Demaji, Majuli, etc. Because of that covering an area of 1325 sq.km in 1917, as of today Majuli has been reduced to roughly around 300 sq.km.
The fury of the floods that Majuli encountered in 2017 can gauged by the fact that at least 50,000 people were affected by the flood and 49 villages and 1760 hectors of crop were damaged. Majuli has shrunk from 1256 sq km in 1971 to only 524 sq km in 2016 loosing half of its area. 67 villages have eroded away by Brahmaputra floods. The way to reach Majuli is a two hour ferry ride from the mainland. The island is known for its rich biodiversity, native tribal populations residing in stilted homes. Fig. 4.1
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Majuli Island is the world’s largest inhabited river island. It is situated in Brahmaputra basin. The island has great importance in Assam as it preserves the unique cultural heritage of Vaishnavism. The length of the island is 80km from east to west and 10-15 km wide from north-south. The government has constructed 155 km of embankments. The long South-West embankment is a lifeline of Majuli. High flood discharge in Brahmaputra sometimes causes breaches in the embankments cause difficult situation in the Island. “A total length of about 42 km has been retired over the last 20 years and now 88.3 km of embankments are in existence. The total landmass of Majuli Island in 1914 was 733.79 sq km which was reduced to 506.37sq km in 2008, but there is an increase in the landmass of Majuli Island to 522.73 sq km in 2013. In 2013 the Brahmaputra board reclaimed 2.47 sq km area in the Majuli Island by raising and strengthening of 96.2 km of Embankment. The average annual rate of erosion of Brahmaputra river near Majuli Island is 6.42 km²/yr from 1996 to 2001.” (Sarma, Phukan, 2004)
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4.2 PEOPLE, COMMUNITIES
ENVIRONMENT
AND
Majuli is a land where there is vast diversity of people. Different tribes of people living with each other through the centuries. Majuli inhabits two broader group of settlement classified as Tribal population and Non-tribal population. Communities like Mishing, Deori and Sonawal Kachari covers tribal population whereas Brahmin, Koch, Kalita Nath, Ahom, Kamar, Gwalla covers the Non-tribal population. (*Silk textiles as mediators between space and people in MajuliThesis by Harita) A brief about the dominant tribes residing in Majuli is given below. The Mishing Tribe: The Mishings (Miris) are one of those mongoloid tribes of Tibetan Burnese group who came to settle in the Brahmaputra Valley as early as the beginning of thirteen century. From their folk tales, folk lore and other references they mainly settled along the upper banks of Subansiri and north banks of the Brahmaputra River and later on they spread along the valleys of the Brahmaputra River, the present districts of Sonitpur and Jorhat. Having the tradition of living along the bank of river the habitats of the Mishings were constantly exposed to flood and erosion, for which they had to shift from one place to another very often. The Mishings are regular victims of flood and erosion throughout their long history of settling down in the valleys of river Brahmaputra. They live in “Chang ghar” which are on stilted in order to avoid the flood water. Mishing are highly skilled in weaving. The women hold expertise in traditional knowledge in weaving. The day to day life revolves around agriculture and weaving. The raw material acquired for weaving are locally sourced, cultivated using sustainable approach hence the people are closely connected with nature. Through the use of indigenous materials and simple looms they produce apparently fine and colourful textiles. These designs are inspired by the locality i.e Flora and fauna.
Fig. 4.3
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The kumar community:
4.3 TRADITIONAL CRAFT OF THE PEOPLE
The kumar community lives near the banks of Brahmaputra. They do pottery for living. They dig the locally available clay form Brahmaputra to make pot, and sculpture etc. Their house forms generally have storage space below the house or separate storage room to store clay items.
There are various art and craft that people do in Majuli, Including dance forms, Festivals and Agriculture. Country loom : World famous Mirizim and Kingkhap Balichori are some of the famous items of the looms of Majuli. Besides spinning of endi, muga and mulberry silk is extensibely practiced here. Every family has at least one weaver to weave cloth for their social use.
The Deoris: The Deoris community belongs to the Tibetan-Burmese group of Mongoloid race. They have four main branches namely Dibangia, Tengaponia, Bargaya and Patargaya. They reside at the upper part of Majuli in Chiram Deori village on the banks of Subansiri River and other Major Deoris lie on the banks of Kherkutia River.
Fig. 4.5 Weaving
commute to different areas they use boats as the road networks are unavailable. The people in Salmora make boats from locally available wood.
Pottery: The art of pottery is an age old tradition that depicts the mastery of the kumar community of Majuli, Salmora and Chiatali are the villages where pottery has become important options of livelihood for people. Besides items of day to day use, they also make various types of dolls, idols, decorative items etc. Fig. 4.6 Pottery
Fig. 4.7 Boat making
Fig. 4.4
Bamboo and Cane craft: Assam is known for its bamboo and cane products. Almost all the village households of Majuli are engaged in making bamboo items like Jakoi, polo, Chepa, Khaloi, Chaloi, dola, Kula, Khorahi, Panchi etc.
Mask making: The satras in the region is a cultural hub. ‘Bhaona’ or local theatre enacting religious stories is a prime feature of these satras. Masks are extensively used in these ‘Bhaonas’ and hence the craft of mask making becomes a unique feature of Majuli. They use different characters to make colourful masks Evil, God etc. They also perform Hindu stories like Ramayana during festivals wearing those masks. Boat making: There are people who do fishing for living. They sell the fishes to main markets in Garmur and Kamlabari. During the times of flooding for
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4.4 FIELD VISIT During the field visit five different villages which had different flood estimation levels, are selected for further study. Each of these villages had different construction methods and materials used in houses are different. These are the houses that are documented during field visit. Following list is showing six villages that are selected for study. Which are different locations in terms of proximity to Brahmaputra River and flood estimation level. (I) Chitadar suk (II) Garmur (III) Salmora (IV) Dhakinpat (V) Uttar Kamlabari (VI) Kamlabari
Fig. 4.8 Villages visited [ PAGE INTENTIONALLY LEFT BLANK ]
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4.4 HOUSES DOCUMENTATION
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TYPOLOGIES Based on the observation during the field visit, houses are devided into five typologies.
Fig. 4.9
Site inferences
Fig. 4.10
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4.5 CASE STUDIES
4.5.1
Fig. 4.14 Section Fig. 4.12 Bambu social
Fig. 4.13 Plan Fig. 4.15 Section
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4.5.2
Fig. 4.16 Black Bamboo Cemter
Fig. 4.18 Section
Fig. 4.17 Black Bamboo Cemter
Fig. 4.19 Section
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4.5.3
Fig. 4.20 Mokoko floating school
Fig. 4.22
Fig. 4.21 Mokoko floating school Fig. 4.23
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4.5.4
Fig. 4.24 Panyaden School
Fig. 4.25 Panyaden School
Fig. 4.26 Process of construction
Fig. 4.27 Plan and 3d view
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4.5.5
Fig. 4.30 Roof made out of dried leaves
Fig. 4.28 Temporary shealter
Fig. 4.29 Temporary shealter Fig. 4.31
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Fig. 5.1
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Fig. 5.2 Unit plans
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Fig. 5.3 Cluster activities
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Fig. 5.4 Cluster activities
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Fig. 5.5 Community master plan
Fig. 5.6 Unit sections
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Fig. 5.8 Physical models
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6.1 QUESTIONNAIRES
HOUSING DETAILS
These are the Questionnaires that is prepared during the field visit.
Water supply: Source of water: Sewage system? Individual/Government? Govt. connection / Individual Distance to the source supply Supply frequency / DAY: Quality of water How do they use water during the flood? Electricity: Domestic connection Y/N Duration Voltage
6.1.1 HOUSEHOLD QUESTIONNAIRES Village name: ___________________________________________________ Location: _______________________________________________________ Name of householder: ____________________________________________ Community: ____________________________________________________ Phone Number: _________________________________________________ Household characteristics: Household size: ________________________________________________ Land owned by: _________________________________________________ Irrigated land____________________________________________________ Land cultivation in one year: ______________________________________ From how many years do they live here? How do the access the house? How old the house is? What materials do they use to make it? Concrete / Bamboo / Thatched / Iron / Wood / G.I sheets / Asbestos / Brick In what time they have constructed? Where do they gather? What do they do for living? What changes do they do during floods? Household’s assets? (If required) Vehicles / Animals / Other.
TIME:
Built-up area: ___________________________________________________ Plot area: _______________________________________________________ Individual spaces area:
CONSTRUCTION MATERIALS Roof Walls Floor Connections / Joints Plinth Paved / Unpaved area Fencing What changes do they prefer in house? What do you expect form the government? Or from any NGOs’? Climatic response:
THINGS RELATED TO CULTURE Pros/Cons of the house What is the social structure? Role of women? What do they do throughout the day? What crops do they cultivate Period of harvesting Storage of grains What do they do for the maintenance? What element/materials do they change or they need to maintain? Wall Roof Plinth Foundation
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SOCIAL AMENITIES Education: Health: Transport: Others:
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6.1.2 QUESTIONNAIRES FOR THE ARCHITECTS
6.1.3 QUESTIONNAIRES FOR THE LOCAL CONTRACTORS
Name of the Architect: _________________________________________ From how long you are practicing: ______________________________
Name of the Architect: _________________________________________ From how long you are practicing: ______________________________ Contact number: _______________________________________________
How do they design the structures to resist the natural disasters? What is the common construction methods do people use for constructing the house? What are the common spaces they find in each case? What are the similarities between them? (Villages) What materials do people easily get from the market in case of your practice? What are the things that are changing in construction through period of time? Material Spaces Details, because of technology? Beliefs / People’s mentality? Are workers/ Masons easily available? Labour cost? What type of foundation do they do in less SBC (Soil bearing capacity) or in erosion prone zone? What are the steps that government takes? Does it actually help people? What is the availability of materials in Jorhat/Morigaon? What is the particular thing that people have to (or they usually) consider while making the house? Like vastushastra? What people usually prefer Builders/Architects/Contractors/on their own?
Who are the clients usually? What materials do they use for Different elements? From where do they get materials? Jorhat Guwahati Majuli
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How do they transport materials? What is the cost of Materials? Bulk
With transportation
Brick Cement Sand Water Bamboo Wood G.I sheets Steel What is the cost of machines per day? How do you implement the whole project? (Collect sample drawings if possible) What is the trend now? Is it the need or is it the flow? Shift of materials? How much you’re paid for one project? Where do you get the masons/workers from? How much they charge per day? What treatment people do on bamboo? (Collect the samples of Ikra, wood, bamboo or any other materials) What do they take care of load transferring during flood/Earthquake? When is the labour paid high? Any specialized people for certain work? What is the daily work schedule?
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6.2 INTERVIEWS
BIBLIOGRAPHY
Mr Chitranjan in Chitadar suk, about the traditional knowledge of construction on 31st march, 2018
n.d. 4 8 2018 <http://bharatonline.com/assam/travel-tips/location.html>. (NHC), NORTHWEST HYDRAULICS CONSULTANTS. “RIVER FLOODING AND EROSION.” (2006). Acharjee S, Konwar M. “IMPACT OF FLOOD AND RIVER BANK EROSION ON SOCIOECONOMY.” International Journal of Geology (2013). Analysis, Weather. Assam state disaster management autority. n.d. <http://sdmassam.nic.in/ >. Arun kumar talwar, Satish Juneja. Flood Disaster Management. Commonwealth publisher, 2009. Assam, Government of. Statistical Handbook of Assam Directorate of Economics and Statistics. Guwahati, 1996. —. Statistical Handbook of Assam Directorate of Economics and Statistics. Guwahati, 2009. —. Statistical Handbook of Assam. Directorate of Economics and Statistics. Guwahati, 2008. —. Statistical Handbook of Assam. Directorate of Economics and Statistics. Guwahati, 2010. authority, Assam state disaster management. n.d. 21 4 2018 <www.sdmassam.nic.in>. Barua, Priyanka. Livelihood Vulnerability Assessment of Weavers in Majuli, Assam. 2013. Board, Brahmaputra. “Protection of Majuli Island from Floods and Erosion.” (2012). Bora, Mukul Chandra. “The Flood Situation of Assam – A Case Study.” 2014. Bora, Mukul. “The Flood Situation of Assam – A Case Study.” 2014. Buragohain, Urmi. LIVELIHOOD STRATEGIES FOR RESOURCE MANAGEMENT. Ahmedaabd, 2001-2002. Das, P.J. Rainfall regime of northeast India: A hydrometeorological study with special emphasis on the Brahmaputra. Guwahati: Unpublished PhD thesis, 2004. Debendra Kumar Nayak,Mayuri Das. “An assessment of Redistribution of Population in Majuli Island due to river.” n.d. <https://iussp.org/sites/default/files/event_call_for_papers/iussp13. pdf>. Eschooltoday. n.d. 21 6 2018 <http://eschooltoday.com/natural-disasters/floods/types-of-floods. html>. Forest Man. Dir. William Douglas McMaster. Perf. Jadav Payeng. 2014. Glancey, J. “Nagaland: A Journey to India’s Forgotten Frontier.” 2011. Gogoi, Prasujya. “https://www.linkedin.com/pulse/shrinking-world-largest-inhabited-river-islandmajuli-prasujya-gogoi.” n.d. Goswami, DC. Fluvial regime and flood hydrology of the Brahmaputra River. n.d. —. The Brahmaputra River. Ecologist Asia Vol.11 (1)9-14, 2003. hindu, The. The hindu. n.d. <http://www.thehindu.com/migration_catalog/article11834152. ece/ALTERNATES/LANDSCAPE_615/ASSAM_INTERNET>. Hindu, The. Thehindu. n.d. 23 6 2018 <http://www.thehindu.com/news/national/other-states/ all-you-need-to-know-about-assam-floods/article19629482.ece>. kale, V.S. “ Flood statistics in India, Geological Society of India, Memoir.” 1998. Kolkman, Rene. Tribal Architecture in NorthEast India. 2003. —. Tribal Architecture in NorthEast India. Brill Publication, 2003. —. Tribal Architecture in NorthEast India. 2003.
Mr Pradip Deka, officer at Water resource department, Garmur, Majuli about the protection of island due to erosion on 2nd April, 2018. Mob no. 9508678740 Mr Aliul Akhtar, officer at Water resource department, Guwahati about the overall scenario of flood and erosion in Assam on 5th April, 2018 Mob no. 9435385285 Prof. Rajesh Dutta, structural engineer at Assam state disaster management authority, Guwahati, Assam on strategies of fighting the natural disasters on 30th march, 2018. Mob no. 9435567470 Mr Pradip Bezbaruah , NGO worker, Majuli on construction rates and for understanding the region on 4th April, 2018. Mob no. 9435692027
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MAJULI. Dir. Aniruddha Barua. Perf. NILOTPAL BORA. 2017. Majuli: Assam’s Disappearing Island . 2017. Management, Department of Water Resources Development and. “STUDY OF BRAHMAPUTRA RIVER EROSION.” (2012). Mandira Buragohain,Monimugdha Bhuyan. “Impact of Flood and Siltation on Socio-Economy.” 2014. Manoj Kumar Singh, S. M. “Bioclimatism and Vernacular Architecture of North-East India.” 2011. metawala, Prachi. “Commune Ark.” n.d. Nag Subhankar, Gondane Amol. “Architecture of North East India: Vernacular Typologies.” n.d. Navanita Das, Shulanki Pal, Spondan Sapon Bora, Onenjungla Walling. “Study of Traditional Houses in Assam.” 2014. Navnita Das, Shulanki Pal, Spondan Sapon Bora. “Study of traditional houses in Assam.” Royal Group of Institution Guwahati, Assam (n.d.). Navnita Das, Shulanki Pal, Spondan Saponbora. “Assam type houses : Problems & Prospects.” 2013. Padhi, B.K. “Religious Art and Architecture in North East India.” 2009. Prerona Kaushikl, Nagaraju Kaja. Assam type houses: Problems and Prospects. School of planning and AArchitecture, Vijaywada, n.d. R. B. Singh, B. W. Pandey and Abhay Shankar Prasad. “Adaptation Strategies for Flood Risk Mitigation in Lower Brahmaputra River Basin, Assam through Integrated River Basin Management.” 2014. Rumana, R. “Traditional House of Bangladesh: Typology of house.” 2007. Sarma, Jogendra Nath. “FLOOD AND BANK EROSION PROBLEMS OF THE RIVER BRAHMAPUTRA, ASSAM.” 1998. scroll.in. n.d. 2 7 2018 <https://scroll.in/article/868011/swallowed-by-the-brahmaputramajuli-is-now-half-its-size-can-it-be-saved>. Sharma, J.N. Pattern of erosion and bankline migration of the river Brahmaputra, Assam. Guwahati: National seminar on Disaster management, 2002. Siddhartha K. Lahiri,Rajiv Sinha. “Morphotectonic evolution of the Majuli Island in the Brahmaputra valley of Assam, India inferred from geomorphic and geophysical analysis.” 2014. Sutapa Das,Parthasarathi Mukhopadhyay. “Multi-hazard disaster resilient housing with bamboo-based system.” 2017. THE FOREST MAN. Dir. William Douglas McMaster. Perf. JADAV PAYENG. 2013. today, India. India today. 2 2018. <https://www.indiatoday.in/pti-feed/story/top-ministersdiscuss-on-proposals-of-upper-house-in-assam-495560-2015-10-15>. V.R, Baker. Geomorphological understanding of floods. n.d. Wikipedia. 2 2018. 2018 <https://en.wikipedia.org/wiki/Majuli>. wire, The. “The wire / Cover page.” n.d. <https://thewire.in/wp-content/uploads/2017/07/ PTI7_6_2017_000183B.jpg>. worldbank. “worldbank.” 2 2018. <http://siteresources.worldbank.org/INTSAREGTOPWATRES/ Resources/Background_Paper_5.pdf>.
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LIST OF FIGURES Fig 1.1 Methodology Chart Fig 2.1 Impact of flood and erosion on the Majuli people Fig 2.2 SWOC analysis Fig 2.3 Load transfer diagram during flood, By Author Fig 2.4 Kedarnath flood Fig 2.5 Tsunami in US Fig 2.6 Urban floods in the city Fig 2.7 Flood in Majuli Island Fig 2.8 Water blockage in the city Fig 3.1 Image courtesy: Getty Images Fig 3.2 Impact of flood hazard Fig 3.3 Situation during flood in Majuli Fig 3.4 Census data, Government of India, 2011. Graphics generated by the Author Fig 3.5 Census data, Government of India, 2011. Graphics generated by the Author Fig 3.6 Census data, Government of India, 2011. Graphics generated by the Author Fig 3.7 Hazard maps by Bhuvan satellite, ISRO. Graphics by the Author Fig 3.8 Hazard maps by Bhuvan satellite, ISRO. Graphics by the Author Fig 3.9 Hazard maps by Bhuvan satellite, ISRO. Graphics by the Author Fig 3.10 Hazard maps by Bhuvan satellite, ISRO. Graphics by the Author Fig 3.11 Wattle and Daub house Fig 3.12 Ikra house Fig 3.13 Chang house Fig 3.14 Utilities on the raised structure Fig 3.15 External Loads Fig 3.16 Bamboo joints Fig 3.17 Bamboo joints Fig 4.1 Erosion in Majuli, Graphics by the Author Fig 4.2 Site analysis Fig 4.3 Site locations Fig 4.4 Arts and Crafts in Majuli Island Fig 4.5 Weaving Fig 4.6 Pottery Fig 4.7 Boat making Fig 4.8 Villages visited Fig 4.9 https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSBdtrWdAbMeMPkRGAlTP_1V1fuhL7YGkHXNUUl8hJN15t3RvRdQ Fig 4.10 Conceptual diagram Fig 4.11 Activity diagrams Fig 4.12 Bambu social Fig 4.13 Bambu social Fig 4.14 Section of Bambu social Fig 4.15 Section of Bambu social
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Fig 4.16 Black bamboo community center Fig 4.17 Black bamboo community center Fig 4.18 Section of Black bamboo community center Fig 4.19 Section of Black bamboo community center Fig 4.20 Mokoko floating school Fig 4.21 Mokoko floating school Fig 4.22 Conceptual diagram of Mokoko floating school Fig 4.23 Conceptual diagram of Mokoko floating school Fig 4.24 Panyaden School Fig 4.25 Panyaden School Fig 4.26 Process of construction, Panyaden School Fig 4.27 Plan and 3d view of Panyaden School Fig 4.28 Temporary shelter Fig 4.29 Temporary shelter Fig 4.30 Roof of Temporary shelter Fig 4.31 Temporary shelter Plan and Elevation Fig. 5.1 Conceptual community activities Fig. 5.2 Unit plans Fig. 5.3 Cluster activities Fig. 5.4 Cluster activities Fig. 5.5 Community master plan Fig. 5.6 Unit sections Fig. 5.7 Cluster section Fig. 5.8 Physical models
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