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Introduction toIntroduction toIntroduction toIntroduction toFHM related situation in Lao PDRFHM related situation in Lao PDRFHM related situation in Lao PDRFHM related situation in Lao PDR

Introduction toIntroduction toIntroduction toIntroduction toFHM related situation in Lao PDRFHM related situation in Lao PDRFHM related situation in Lao PDRFHM related situation in Lao PDR

East & Southeast Asia Regional Seminar on Flood Hazard Mapping, 17-19 February 2009, Manila, Philippines

Compiled by Oudomsack Philavong

Main floodplains

• The Vientiane Plain (Vientiane Municipality and

Vientiane province),

• Khammouane Province (Thakhek Town and

Xebangfai Mouth, Hinboun Mouth),

• Savannakhet Province,

• Saravan Province,

• Champasak Province (Pakse Town), and

• Attapeu province

• Louangnamtha Province (Flashflood)

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• Provinces

affected by

Flash Flood

in 2007

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Flood statistics since 2002

Description Flash flood damages

in 2007

Flash flood damages

in 2006

Flood damages

in 2005

Flood damages

in 2002

Provinces affected 4 5 16 13

Districts affected 27 20 84 62

Villages affected 614 404 2,510 1,142

Families affected 25.292 13,549 85,530 50,342

People affected 118. 074 89,849 480,913 249,782

People killed 2 5 5 3

Hectares of rice and crop damaged 74,739.8 6,913 55,955 33,702

Total estimated cost damages in million US$ N/A 3.1 18.3 N/A

Flood in Xebanghieng in 2007

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Flood in Xedone in 2007

Institutional arrangement for flood

mitigation1 Minister of Labor and Social Welfare Chairman

2 Minister of Agriculture and Forestry Vice Chairman

3 Chief of Cabinet , Ministry of Foreign Affaires Vice Chairman

4 Chief of Cabinet, Ministry of Defense Member

5 Chief of Cabinet, Ministry of Security Member

6 Chief of Cabinet, Ministry of Education Member

7 Director General of Budget Department, Ministry of Finance Member

8 Director General of Transport Department, Ministry of Public Works and Transport Member

9 Director of Industry Department,Ministry of Industry and Commerce Member

10 Director of Hygiene Department, Ministry of Public Health Member

11 Director of Mass Media Department, Ministry of Information and Culture Member

12 Director of Social Welfare Department,Ministry of Labors and Social Welfare Member

13 Chairmanof Lao Red Cross Society Member

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Flood Risk Maps implementation

• Xebangfai Basin (done)

• Namtha Flashflood (under preparation)

• Xedone Basin (in progress)

• Xekong Basin (in progress)

Actors in Flood Mapping

• Water and Environment Research Institute

• Department of Water Resources

• LNMC

• Department of Irrigation

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Xedone Flood Mapping

using iSIS Model

Data preparation• Cross-section

Xedone river:

39 cross-sections from field surveyed

Mekong river:

River cross-sections from MRC iSIS Model

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• Topographic Data

DEM (m)

< 100

100 - 120

120 - 140

140 - 160

160 - 180

180 - 200

200 - 400

400 - 600

600 - 800

>800

Digital Elevation Model

(DEM) with 50m of cell size

provided by MRCs

• Reservoir and Spill Data

Reservoirs/Flood cell derived from generating by GIS tool based on water level and DEM and Flood area done by Department of Irrigation

Reservoirs

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• Hydrological Data

Hydrological data available:• Flow :

SWAT modelKhong Chaim Pakse Khong Se DoneBan Done Se Ban Nanay

• Water level:Ban Done SePakse

• Schematization Upper boundary:

Sedone at Ban Vapi

Mekong at Khong Chaim Station

Lower boundary

Mekong at Pakse Station

River Cross-section:

Mekong : 13

Sedone: 39

Reservoir: 17

Spill: 105

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• Calibration (at Souvannakhiri)Calibrated Point

Calibrated Result

108

110

112

114

116

118

120

1-J

an-0

0

1-F

eb-0

0

1-M

ar-

00

1-A

pr-

00

1-M

ay-0

0

1-J

un-0

0

1-J

ul-

00

1-A

ug-0

0

1-S

ep-0

0

1-O

ct-

00

1-N

ov-0

0

1-D

ec-0

0

Obs

Sim

• Results

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Constraints

• No aerial photographs available

Thank you