Assessing flooding measures in Dhaka, Bangladesh by incorporating stakeholders consultation. DHAKA Capital of Bangladesh. High rate of urbanization

Transcription

1 Assessing flooding measures in Dhaka, Bangladesh by incorporating stakeholders consultation Anika Nasra Haque Stelios Grafakos Marijk Huysman Institute for Housing And Urban Development Studies, Erasmus University, The Netherlands DHAKA Capital of Bangladesh High rate of urbanization Active river tidal zone Erratic rainfall Lack of infrastructure Flooding Riverine flood Rainfall induced flood Storm water flood Flood risk

2 Unprotected Study area Study area CBD Assessment framework Vulnerability assessment Adaption assessment Exposure Index Sensitivity Index Adaptive capacity Multi criteria analysis Stakeholders involvement Experts judgment Selection of criteria Weighting criteria Scoring

3 Vulnerability Assessment Climate variability Exposure Sensitivity Adaptive capacity Impact Input Analysis Vulnerability Vulnerability Assessment Exposure Index Hazard Frequency Duration Spatial extent Exposure Index (E.I) Riverine flood Rainfall induced flood Storm water flood Types of capital assets Sensitivity Matrix Sensitivity Index (S.I) (Scale 1-100) Natural Physical Economical Social Ecosystem Flora and fauna 60 Water quality 93 Air quality 53 Soil contamination 47 Property, goods and services Shelter/ housing and other assets 60 Infrastructure 87 Productive sectors Agriculture 67 Trade 80 Fisheries 40 Stakeholders/ livelihoods Squatter and slum dwellers 80 Land owners 40 Tenants 26 Agricultural workers 60 Traders and businessmen 67

4 Adaptive Capacity Considered factors Gender Age Occupation Income Education/awareness Existing infrastructure services One dominating group bearing same status Same access for all the inhabitants Adaptive capacity is assumed to be the same for the whole study area Vulnerable sectors Rank Sectors Category Vulnerability Index (Scale 1-100) 1 Water quality Natural 66 2 Infrastructure Physical 61 3 Trade Economical 56 Squatter and slum dwellers Social 4 Agriculture Economical 47 Traders and businessmen Social Flora and fauna Natural 5 Shelter/ housing and other assets Physical 42 Agricultural workers Social 6 Air quality Natural 38 7 Soil contamination Natural 33 8 Land owners Social 28 Fisheries Economical/ Natural 9 Tenants Social 18

5 Adaptation Assessment Existing proposed measures Proposed measures from case studies Selection of potential adaptation measures Adaptation measures Construction and up gradation of storm sewer/ drainage system Raised road Embankment Flood wall Protection of water retention areas Canal Improvement Enhancing emergency mechanism system Enhancing early warning system Description of measures Structural Structural Structural Structural Non -structural Structural Non -structural Non -structural Stakeholders involvement List of Respondent stakeholders Community representatives (ward commissioners) Representatives from business and farmer community Representatives from Government departments responsible for vulnerable infrastructure sectors Representative from NGO involved with the promotion of environmental and social objectives

6 Stakeholders involvement List of criteria: Based on consensus through Focus group discussion with stakeholders Category of Criteria Criteria Units Objective Vulnerability Vulnerability reduction Percentage Max Financial Cost Millions Min Environmental Enhancement of ecological condition "1-5" Max Socio political Public and political acceptance "1-5" Max Macro economical Employment generation "1-5" Max Socio-economical Achievement of MDG "1-5" Max Institutional & Technological Institutional and technical capacity "1-5" Min Experts scoring Existing Proposed Adaptation Options Structural measures Non structural measures Non structural measures Construction and up gradation of storm sewer/ drainage system Criteria Enhancement Public & Employment Achievement Cost of ecological political generation of MDG ( US $ in condition acceptance (Scale of (Scale of millions) (Scale of (Scale of 1 to 5) 1 to 5) 1 to 5) 1 to 5) 5) Vulnerability reduction (in percentage) Institutional and technical capacity (Scale of 1 to Raised road Embankment Flood wall Canal Improvement Protection of water retention areas Enhancing emergency response mechanism Enhancing early warning system

7 Standardization of options Adaptation options Construction and up gradation of storm sewer/ drainage system Vulnerability reduction Cost Enhancement of ecological condition Public and political acceptance Employment generation Achievement of MDG Institutional and technical capacity Raised road Embankment Flood wall Canal Improvement Protection of water retention areas Enhancing emergency response mechanism Early warning system Experts Scoring of adaptation options

8 Weighting of criteria Finalized as consensus through Focus group discussion with stakeholders Criterion Importance Values Weights Vulnerability reduction Cost Very High High % 80 18% Enhancement of ecological condition High 70 16% Public and political acceptance Moderate 60 13% Employment generation Moderate 60 14% Achievement of MDG Low 30 7% Institutional and technical capacity Low 40 9% Prioritization of options Options Weighted Score Rank Protection of water retention areas Enhancing early warning system Canal Improvement Embankment Construction and up gradation of storm sewer/drainage system Raised road Enhancing emergency response mechanism Flood wall

9 Sensitivity analysis Scenario 1-7: changing variable by 20 units Scenario 8-14: changing variable by 40 units Scope for further research Testing uncertainty of experts scoring to the prioritization by sensitivity analysis Incorporating risk management Detailed climate scenario analysis Detailed adaptive capacity analysis Consideration of temporal scales Further test on criteria weighting A larger sample of stakeholders

10 Thank You Contact: Data analysis scheme Process/ Tool Output Output Input Exposure index Adaptive capacity analysis Sensitivity index Vulnerability Index Input Identification of adaptation options Related Cases bearing similar context Vulnerability assessment Stakeholders involvement Selection of criteria Experts judgment Scoring Stakeholders involvement Weighting criteria Prioritizing options Adaption assessment

11 Sensitivity Matrix Climatic hazards Sensitivity Index Types of capital assets Riverine flood Rainfall induced flood Storm water flood (S.I) (Scale 1-100) Ecosystem Flora and fauna Natural Water quality Air quality Soil contamination Physical Property, goods and services Shelter/ housing and other assets Infrastructure Economical Productive sectors Agriculture Trade Fisheries Stakeholders/ livelihoods Squatter and slum dwellers Social Land owners Tenants Agricultural workers Traders and businessmen Impact Index (Scale of 1-100) Vulnerability Index Sectors Ecosystem Property, goods and services Productive sectors/ livelihoods Stakeholders/ livelihoods Types of capital asset Riverine flood Rainfall induced flood Storm water flood Vulnerability S.I. E.I. V.I. S.I. E.I. V.I. S.I. E.I. V.I. Index (Average) Flora and fauna Water quality Air quality Soil contamination Shelter/ Housing and other assets Infrastructure Agriculture Trade Fisheries Squatter and slum dwellers Land owners Tenants Agricultural workers Traders and businessmen

12 Weighted score Final Score Adaptation Options Vulnerability Enhancement of ecological Public & political Institutional Employment Achievement and technical Reduction Cost condition acceptance Generation of MDG capacity Weights 22.7% 18.2% 15.9% 13.6% 13.6% 6.8% 9.1% 0.52 Construction and up gradation of storm sewer/ drainage system Raised road Embankment Flood wall Canal Improvement Protection of water retention areas Enhancing emergency response mechanism Enhancing early warning system