flood damage assessment for urban growth scenarios · 2013. 9. 9. · flood damage assessment for...

A. S. Chen, M. J. Hammond, S. Djordjević, D. Butler

Flood damage assessment for urban growth scenarios

Outline

• Introduction

• Methodology

• Assessment tool

• Conclusions

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Introduction

Drivers and pressures

Flood hazard assessment

Vulnerability / impact assessment

Responses and resilience strategies

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Introduction

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Introduction

Tangible Intangible

Direct

Physical damage to assets •Buildings •Contents •Infrastructure

Loss of life Injuries Diseases Loss of ecological goods

Indirect

Loss of industrial production Traffic disruption Emergency costs

Inconvenience of post-flood recovery Increased vulnerability of survivors

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Introduction

Image source: Google map

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Flood damage assessment

Damage

Depth

Depth-Damage Curves (DDC)

Land uses

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Depth-damage curves (DDC)

The Benefits of Flood and Coastal Risk Management: A Handbook of Assessment Techniques-2010 (Multi-Coloured Manual), Middlesex University, UK

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Hazard-vulnerability function

Damage Hazard information Vulnerability

Building content/

construction damage

Flood depth

(and duration) Financial loss

Building construction

damage

Flood velocity

(and duration) Building resistance

Pedestrian safety Flood depth Human physical resistance

Pedestrian safety Flood velocity Human physical resistance

Driving safety Flood depth Vehicle resistance

Driving safety Flood velocity Vehicle resistance

Human body health Contamination concentration

(and duration) Human body resistance

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Health-impact assessment

Health Impact

Contamination

Contamination-Health Impact

Curves

Demographic data

Mortality

Depth

Depth-Mortality

Curves (DDC)

Demographic data

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Urban growth prediction

2004 baseline

Dhaka urban growth model (UGM) prediction

2050 BAU high

Reality vs. UGM prediction

Legend

Others

Commercial Activity

Education & Research

Governmental Services

Mixed Use

Manufacturing & Processing Activity

Residential

Reality vs. UGM prediction

0 180 36090m

±

Legend

Others

Commercial Activity

Education & Research

Governmental Services

Mixed Use

Manufacturing & Processing Activity

Residential

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Development environment

• Standard GIS data format adopted

• Integrated with DHI MIKE software

• Python scripts and Geoprocessing functions within ESRI ArcGIS software

• Minimum manual input to calculate the flood damage

• Transportable to other GIS software packages/platforms

• Separate executable programs for additional functions

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Reality – UGM correlation

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Reality vs. UGM prediction

Land

cover

class

Building use

Comm.

Activity

Edu. &

Resear.

Gove.

Services

Mixed

Use

Manuf. &

Proc.

Activity

Residenti

al

1 0.1% 0.0% 0.0% 0.0% 0.0% 3.7%

2 0.4% 0.2% 0.0% 0.2% 0.1% 10.3%

3 0.9% 0.5% 0.1% 0.6% 0.3% 16.6%

4 1.6% 0.7% 0.1% 1.3% 0.7% 21.4%

5 2.4% 0.8% 0.2% 2.0% 1.4% 26.5%

6 3.2% 0.9% 0.2% 2.7% 2.7% 31.5%

7 4.1% 0.8% 0.2% 3.6% 4.5% 33.9%

8 6.3% 0.8% 0.3% 5.9% 7.4% 30.8%

9 9.8% 0.9% 0.5% 12.6% 8.4% 21.4%

10 11.0% 1.2% 0.5% 36.4% 2.8% 12.6%

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Flood damage per building

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Flood damage per unit area

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Local comparison

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Citywide comparison

Building use type Damage (USD)

Comm. Activity 154,361

Edu. & Resear. 54,519

Gove. Services 27,274

Mixed Use 652,138

Manuf. & Proc.

Activity 275,122

Residential 3,514,702

Total 4,678,115

Land cover class Damage (USD)

1 208,660

2 399,085

3 461,626

4 576,391

5 860,895

6 1,027,854

7 1,239,475

8 737,415

9 348,880

10 193,718

Total 6,053,999

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

UGM prediction

2004 baseline 2050 BAU high

UGM prediction

2004 baseline 2050 BAU high

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Future damage

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Conclusions

• GIS-based tool for flood damage assessment

• Capable utilising the hydraulic modelling results directly

• Evaluate the flood damage efficiently

• Associate the land cover classes to the current reality, correlation to be improved

• Applied to assess flooding damage for future urban growth

• Possible applications for different hazard-vulnerability analyses and other future scenarios

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Acknowledgements

• Research on the CORFU (Collaborative research on flood resilience in urban areas) project was funded by the European Commission through Framework Programme 7, Grant Number 244047.

• The authors appreciate the Institute of Water Modelling (IWM) for the provision of case study data and William Veerbeek for the UGM modelling results.

International Conference on Flood Resilience: Experiences in Asia and Europe, 5-7 September 2013, Exeter, UK

Thank you and questions?

Further information: http://corfu7.eu

Contact: a.s.chen@ex.ac.uk