Land Suitability Analysis for Habitant

Relocation in Debris Flow Prone Area

Department of Urban Planning, Cheng-Kung

University

Han-Liang Lin

Contents

• Background: Emergence the issue of

Relocation

• Framework of location seeking for relocation

• Identify villages of High Debris Flow risk

• Aspects of re-location projects

• Case study in Shiaolin Village

• Summary

Taiwan has a high disaster risk in debris flows that there were 1,420 streams vulnerable to debris flow in 2003, 1,503 in 2009 and 1552 in 2010 according to the statistics of the Soil and Water Conservation Bureau

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Long duration of heavy rainfall High concentration Complex topography

Background: Emergence the issue of Relocation

Typhoon Accumulated Rainfall (mm)

Evacuation(Person)

2001 Nari 1,462 24,000

2004 Mindulle 2,005 9,500

2005 Haitang 2,124 1,208

2005 Talim 766 1207

2005 LongWang 776 945

2006 Bilis 1,013 409 2007 Sepat 1,399 2,531 2008 Kalmaegi 1,027 179 2008 Fung-Wong 830 1,303

2008 Sinlaku 1,608 1,987

2008 Jangmi 1,137 3,361

2009 Morakot 2,965 24,775

2010 Fanapi 1,128 16,568

2010 Megi 1,195 3,453

Flooding compound with debris flows within villages around mountain area

More and more extreme climate events : The frequency of extreme typhoon rainfall during 2000~2009 has a significant increase compared with period of 1970~1999 in Taiwan.

The top 20 extreme heavy rainfall typhoons during 1970~2009

Background: Emergence the issue of Relocation

Background: the issue of Relocation in Taiwan

• There were 11 villages relocated after Typhoon Morakot hit Taiwan in 2009.

• Village Shiaolin was almost vanished and the disaster claimed the life of near 500 people

1. Mountain area in Taiwan is debris flows prone area. 2. Relocation is an issue for many county/city government.3. Relocation is difficult and complicated in post-disaster

reconstruction.4. Although each relocation project has its own story ,

normative procedures is still required.

Framework of location seeking for relocation

• Scale : The resolution accuracy may not fit the need

• Up-to-date : short of data maintenance

• Missing or not available

• Redundancy

• Inconsistency in terms of time, purposes, zone scheme etc.

II: Identify High Disaster Risk Area

I: Establish Databases - Issues of uncertainty in disaster databases

Framework of location seeking for relocation

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Risk Level # of Village % Area %

Low 615 63.86 9.94 27.90%

Medium 214 22.22 11.65 32.71%

Medium-High 90 9.35 7.54 21.18%

High 44 4.57 6.48 18.21%

總計 963 100.00% 35.61 100.00%

Most vulnerable county to debris flow disaster are

the county of NanTou, Chiayi, Taichung and

Tainan. The area exposed to the disaster are

212.8 Km2 、 156.83 Km2 、 72.79 Km2 、 64.56

Km2 accordingly 。

Identify High Debris-flow risk villages

Identify High Debris-flow risk villages

1. Who is the user? If it is possible to customize the information for the user?2. Does the map tell the right story or say the story we prefer?

Six Aspects of Relocation

Six aspects of relocation

legality in procedures, Safe security in location, feasibility in finance, identity of society/culture preserved opportunity for economic development willingness to cooperation

The first three are mainly government authority concerns and the others are related to the welfare of people to be relocated.

高縣 DF007( 高雄 A015)•Location ： Shiaolin, Kaohsiung•Catchment ： Kaopin River•Susceptibility level : low•Hazardous Scores ： 128.16

高縣 DF006( 高雄 A014)•Location ： Shiaolin, Kaohsiung•Catchment ： Kaopin River•Susceptibility level : updating•Hazardous Scores ： 128.16

高縣DF006 高縣 DF007

高縣DF005

高縣 DF005( 高雄 A004)•Location ： Shiaolin, Kaohsiung•Catchment ： Kaopin River•Susceptibility level : low•Hazardous Scores ： 128.16

原小林國小所在地

Village ： ShiaolinRisk Level ： MediumRisk Ranking Oder ： 43-7Area exposed to Debris flow ： 6ha

Location assessment for relocation: Safety Aspect

Location assessment for relocation: Legality Aspect

Location assessment for relocation: Legality Aspect

• Location within village, away from disaster

• Location within neighbor villages, away from disaster

可用土地分佈

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Location assessment for relocation: Accessibility

Accessibility Index for assessing identity of society/culture preserved

opportunity for economic development

willingness to cooperation

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Disaster Susceptibility examination over Google Earth

Debris Flows

Flooding Prone Area

Landslide Prone Area

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Land ownership examination over Google Earth

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Topographic Examination over Google Earth

Field Survey for Relocation SiteInterview for historical disaster experiences, observation of community changes both in physical environment and social environment

Picturing evidences of disaster stroke, and potential factors of disaster susceptibility

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8. 小林村舊址現況，後方為及為獻肚山崩塌處

9. 由五里路往楠梓仙溪河谷處拍攝

Field Survey for Relocation Site

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Field Survey for Relocation Site

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Field Survey for Relocation Site

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Summary

• Relocation is an issues of cross-scales

• Relocation is an issues related to multi disciplines

• Relocation success requires no-gap cooperation vertically and horizontally among each level of government institutions

• Databases for disaster risk management has to watching the issue of data/information uncertainty

• There were concluded six aspect factors of relocation that domain the characteristics of relocation in turn.