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Landslide is a general term for a wide variety of downslope movements of earth materials (Elliott C. Spiker and Paula L. Gori, 2003)
&
Development refers to the any change over space and time by human activities.But when it does not take account for all possible adverse effects on human and nature – it is unplanned development
Introduction
1968 - First Recorded Landslide: Kaptai - Chandraghona
Road
1974 - First Recorded Landslide Fatality: 2 Persons in
Chittagong University Area
2007 - Massive landsides in Chittagong City and
surrounding Areas: 128 died, more than 150 injured
2012 - At least 162 died in different hilly areas due to
landslides
Occurrences
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20
40
60
80
100
120
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160
180
1999 2000 2003 2004 2005 2007 2008 2009 2010 2011 2012
Year
Number of Fatality due to Landslides
Total 510 deaths, 88 % of which are from year 2007
In spite of all mitigation and adaptation measures, landslide
fatalities have been continuously been increased in last decade
Triggering factor
70 % of all landslides occur within last 20 days of June
91.67 % within June to August (Monsoon Season)
Analysis of rainfall data from 7 BMD stations of hilly areas shows that:
3 days continuous rainfall of around 390 mm in hilly areas triggers landslides
Some scholars (Khan and Chang, 2007; Mahmood and Khan, 2010)opined that excessive rainfalls within shorter period of time
It can be said that: Landslides in Bangladesh are rainfall triggered
Is there any relationship between recent urban development works and
landslide incidents?
Research objective
This research will try to find out the answer of this question
Landslide incidents and associated fatalities and damages have been increased, caused mostly by the social factors rather than physical (Alexander, 2005)
Literature review
Increasing trends of landslides fatalities have been variable attributed by the effects of population growth and urbanization (Oven et al., 2008; Alexander, 2005)
According to Schuster (1996) worldwide landslide activity is increasing due to:
• Increased urbanization• Continuous deforestation• Increased regional precipitation
Literature review
Rapid sub-urbanization development and habitation in hilly region results in increasing risks of landslides (Phiffer & Norris, 1989; Burke et al., 2002)
Losses of landslides can be reduced by means of effective planning and management (Dai F C; Lee C F; Ngai Y Y; 2002)
Burke et al. (2002); Qi and Zhang (2011); Kutluca and Ozdemir (2008) have drawn examples of increasing landslide incidents with urbanization and development work from Western Washington, Jinan City of China and Tukey respectively.
Landslide locations
Larger clusters of landslides found in • Chittagong City and University
area: 28 landslides, 238 deaths
• Cox’s Bazar Paurashva: 20 landslides, 103 deaths
• Teknaf Paurashva: 44 deaths
• Bandarban and Lama Paurashva: 166 deaths
• Rangamati
Research findings
93.75 % of all Landslides in Bangladesh occurred in any of the urban areas
43 % landslides in Chittagong City
Unoccupied or less densely populated hilly areas are scarcely reported for landslide disaster
In these hilly urban areas: from 2001 to 2011
• urban population increased 28.83 %
• number of household increased 38.79 % in urban areas
Research findings
To find out the factors and recommendations for landslide; a questionnaire
survey was done in seven different landslide prone zones of Chittagong City
( Supervised by Dr A Q M Mahbub)
Surveyed Area (N = 329)
Area Percentage
Motijhorna 47.89
Foy’s Lake 17.17
Jalalabad 12.05
Batali Hill 8.51
A K Khan Hill 6.63
Kushumbag 4.82
Ambagan 2.11
Research survey
Some of the pictures of the areas surveyed: all are basically poorly developed slum areas
Research identified following factors responsible for landslide:
Deforestation
Hill cutting
Water logging
Settlement making
Cultivation in hill slope
Mahmood and Khan (2010) have identified following aggravating factors of landslides for Bangladesh:
Hill cutting
Unsustainable landuse(construction, cultivation etc.)
Deforestation
All these mentioned factors above are somehow related to human intervention on nature or development activities
Research findings
Road construction
Responsible parties for Landslides
Local musclemen/ politicians: making settlements, workshops, factories, other profitable venture
Immigrants: making settlements, means of livelihood
Landowners: property development, making settlements, other profitable venture
Government and it organizations: Infrastructure and institutional development, roads and other facilities etc
Research findings
Recommendations by the vulnerable communities
Stop hill cutting through strong law enforcement and awareness generation
Through afforestation and stopping deforestation
Developing well planned water drainage system and road network with concrete walls
Making local club or association to protect people from landslide risk and developing awareness
Government, non-government authorities should also concentrate to enhance the socio-economic status of the vulnerable communities
Keeping hilly landscapes undisturbed as much possible
Incorporating landslide hazard mitigation plan in all development activities of hilly areas. (like road construction, housing/ real estate development etc.)
Research findings
Thank You
