I Introduction II Damage and Losses. Dr. Hsu, Ming-Hsi

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1 Workshop on the Framework of Long-Term Capacity Building for Disaster Risk Reduction in APEC Lessons Learned from Typhoon Morakot Dr. Hsu, Ming-Hsi Deputy Director, National Science & Technology Center for Disaster Reduction Professor, National Taiwan University Chinese Taipei 2 I Introduction II Damage and Losses III Lesson Learned IV Conclusions

2 3 I Introduction 4 Introduction Before the end of June, we face a challenge of the drought problem. In the southern island, it did no rain in 60 consecutive days. The water storages in main reservoirs decreased to a lower stage for operations at that time Shihmen Reservoir : 69 million tons (33%) Zengwen Reservoir : 126 million tons (21%) Nanhua Reservoir : 28 million tons (24%). We expect Typhoon Morakot bringing rainfall to quench the drought. The Typhoon Morakot affected northern island on Aug 7-9 The Typhoon Morakot affected northern island on Aug. 7-9, but it results the worst flood in 50 years at southern island

3 5 Course of Typhoon Aug 5-6: Moved fast toward Chinese Taipei. Aug. 7 : Slowed down and out skirt touched the island. Aug. 8 : Made landfall at 00:00; Center left the island at 14:00 at very slow pace. Aug. 9 : Gradually moved toward China. 6 Doppler Radar Image The Central Ridge Eye Unsymmetrical structure of rain clouds around dtyphoon The typhoon rain cloud interacted with supplying extra moisture by southwest monsoon result large amount of rainfall in the south of the island.

4 7 Southwest Monsoon Interacted with Morakot by Supplying Extra Moisture Morakot Chinese Taipei 8 Accumulated Rainfall of Typhoon Morakot Accumulated Rainfall County Township Annual Rainfall (mm) 08/07-08/10 (mm) 08/07-08/10 vs Annual Chiayi Alishan 3,910 2,965 76% Pingtung Sandimen 3,884 2,872 74% Chiayi Jhuci 3,801 2,775 73% Kaohsiung Taoyuan 4,086 2,790 68% Kaohsiung Liouguei 3,138 2,461 78% Chiayi Fanlu 3,437 2,202 64% Chiayii Dapu 2,749 2,156 78% Kaohsiung Jiasian 2,861 2,020 71% Nantou Sinyi 3,254 1,929 59% Kaohsiung Maolin 3,152 1,404 45% Pingtung Wutai 2,898 1,160 40% Kaohsiung Cishan 2, %

5 9 Rainfall Intensity Compared with World Records Accumulated Rainfall World Record World Record MORAKOT Morakot Rainfall(mm) hr 3hr 6hr 12hr 1day 2day3day Duration(min) Source: WRA, MOEA 10 II Damages and Losses

6 11 Levee breaks of Linbian River, Pingtung County 資料來源 : 屏東科技大學災害防救中心破堤 12

7 13 Damaged Levees by Flood Taimali Township of Taitung County, East Coast Drifted tree trunks /08/ townships (45% of 319) flooded

8 15 Tainan County 北鹿寮溪庫鹿寮溪庫 kilometres 後鎮後鎮排菁菁寮寮排排 The southern science park situates at Tainan County, one of the most important industrial bases, has no inundation and damage due to well well-established established drainage systems and four detention ponds with 45 hectares. 後壁鄉後壁鄉八掌溪八掌溪排排林樹樹林烏許秀才排許秀才排大吉貝耍排腳腳吉貝耍排腿排排德元埤德元埤尖山埤尖山埤柳營鄉柳營鄉港排龜子龜子港排白河庫白河庫白河鎮白河鎮新營市新營市急溪急溪新田田寮寮排鹽鎮鹽鎮三寮灣堤外線排路三寮灣堤外線排路北門鄉北門鄉將軍溪排將軍溪排山子腳排山子腳排漚汪排學甲鎮學甲鎮將軍鄉將軍鄉大寮排七股鄉七股鄉六成排劉厝排六甲鄉六甲鄉麻豆鎮麻豆鎮烏山頭庫官田鄉烏山頭庫官田鄉番子田排番子田排後後官田溪官田溪佳里鎮佳里鎮營營渡子頭溪渡子頭溪排排溪尾排溪尾排大內鄉大內鄉山石子瀨排石子瀨排西港鄉西港鄉善化鎮善化鎮上大內排大內排排安定排排內江排內江排安定鄉安定鄉新市鄉新市鄉山上鄉那拔林溪那拔林溪洲排大大曾文溪曾文溪排溪排鹿耳門排鹿耳門排鹽溪鹽鹽溪鹽溪下營鄉下營鄉曾文庫東山鄉東山鄉楠西鄉楠西鄉玉井鄉玉井鄉南化庫南化庫南化鄉南化鄉虎頭溪排虎頭溪排永康排永康排新化鎮新化鎮左鎮鄉左鎮鄉 southern 桔子溪排 science park 永康市永康市埤子頭排埤子頭排仁德鄉仁德鄉宮排爺宮排三爺溝溝歸仁鄉二仁溪二仁溪三歸仁鄉尾尾港港關廟鄉關廟鄉龍崎鄉龍崎鄉 >600 (單位 cm) (資料來源:台南縣政府) 16 Soil Deposition in Rivers Slopeland Remains Sediment Outflow Sediment Yields 1.2 billions m3 Slopeland Remains 0 8 billions m3 0.8 Sedimentation in Rivers ve s 0.4 billions m3 Upstream 0.15 billions Downstream 0.25 billions Source: SWCB

9 17 Sediment Deposition in Rivers Bid Bridge at Liukuei ( 六龜 ) Township After Before Source: Kaohsiung County 18 Siaolin Village_the Hardest-hit Area Jiasian Township of Kaohsiung County 400 dead and 53 missing Landslide, barrier lake and mudslide Buried Area Before After

10 19 Aerial Imageries of Siaolin Village Imagery in 2007 Imagery of Aug. 15, Dam Safety for Reservoir In the Morakot, the peak inflow of Tsengwen reservoir was 11,729 m 3 /s which exceeded the spillway capacity of 9,470 m 3 /s. Fortunately, there are no severe damage in the reservoir. We wonder that the extreme rainfall may happen in the catchment of other main reservoirs, especially in Shihman Reservoir at upstream of Taipei city. Item Reservoir Tsengwen Nanhua Shihmen Catchment area (km 2 ) Morakot Peak Inflow (m 3 /s) 11,729 3,030 Morakot Peak Outflow (m 3 /s) 8,367 2,718 Spillway capacity (m 3 /s) Spillway capacity/catchment area (mm/hr) Inflow of Reservoir/ Spillway capacity

21 Capacity Loss of the Reservoir Bf Before the Typhoon Morakot, the

reservoir and 18 million m 3 in Tsengwen reservoir.

directly constructed in a river usually suffered ed from the

11 21 Capacity Loss of the Reservoir Bf Before the Typhoon Morakot, the total sedimentation i of f40 reservoirs was 300 millions m 3 (13.02% of effective capacity ). At the typhoon Aere (2004), 28 million m 3 deposited in Shihmen reservoir and 18 million m 3 in Tsengwen reservoir. At the Typhoon Morakot, about 70 million m 3 deposited in Tsengwen reservoir. The sedimentation deposited in reservoir will reduce the effective capacity of storage for water supply. 22 Off-Site Reservoir- Alternative Solution for Sediment Dam directly constructed in a river usually suffered ed from the sediment e deposited in reservoir, like most of reservoirs in the island, especially faced on the climate change. The off-site reservoir, having small river catchment and water intake from other river, need to consider in the future.

12 23 III Learned from Typhoon Morakot 24 31I 3.1 Improving the Accuracy of frainfall and Flood Forecasting during Typhoon

25 The Real Time Flood Forecast System Three Steps to

Prediction In-time Operation Provide updated data based on

Reference for revising decision support Limited by number,

Tool for pre-disaster deployment Reference for decision

based on well-defined plan Tool for saving more time before

Limited by determination of all-level administrators 26

Though h we have 406 real-time rainfall gauges and d4

insufficient to emergency response for large scale weather

13 25 The Real Time Flood Forecast System Three Steps to Emergency Response Rea-time Monitoring Scientific Prediction In-time Operation Provide updated data based on gauges g Tool for pinpointing blind areas by forecast Reference for revising decision support Limited by number, location, transmission Provide forecasting based on models Tool for pre-disaster deployment Reference for decision support Limited by technology development Provide reaction based on well-defined plan Tool for saving more time before it s too late Reference for allocating emergency support Limited by determination of all-level administrators 26 Enhancement of Typhoon Monitoring System 1. Though h we have 406 real-time rainfall gauges and d4 Doppler radar stations around the island, it is still insufficient to emergency response for large scale weather variations. 2. A regional weather information platform is needed to improve the accuracy of rainfall forecasts.

14 27 River Monitoring System is an Essential Element to Flood Warning The Danshuei River Flood Forecasting System provides flood warning with 6-hr lead time river stage forecasting for the metropolitan Taipei area. The system should be implemented in other major rivers in the island Strengthening the Emergency Response and Relief at all Levels

15 29 Detestation After Typhoon Blocked Emergency Relief 1.Major challenges to emergency rescue Bad weather condition jeopardized air-lifting operation Interruption of roads and bridges restrained access to the affected areas. More complexity of severe weather and interrupted transportation than the 1999 Chi-Chi Earthquake 2.At initial stage right after typhoon, government takes critics and pressure from the media and the public 30 Mobilization of Military Sectors to Speed up Emergency Response and Post-Disaster Recovery Item Number Military personnel 134,792 Flights of Helicopter 1,652 Flights of Aerial Surveillance 21 Military Vehicle 4,000 Non-military Vehicle 5,156 Rubber Boat 269 Machinery 300 Boat 5 Emergency Relief Material 227 ton

16 31 Case Comparison of Pre-disaster Evacuation from the Typhoon Morakot Without Pre-disaster Evacuation j landslide before,, Because of no major villagers decided to stay Spot: Siaolin Village, Jiasian Township Damage and causality: the landslide Damage cased 350 damaged houses and 453 people dead With Pre-disaster Evacuation Villagers followed the red alert of debris flow Spot: Yushan Village, Village Nanhua Township No causality reported If no evacuation in time, the 50 damaged h houses could ld cause the th number b off causality to Strengthening disaster preparedness measures and rescue resources in local governments executors Community residents are the executors. Through various activities to encourages participation Provide needed knowledge and resources. discussion workshop lecture field survey mapping education meeting training training parties exercise

17 Improving Land Use Management and Land Conservation Planning 34 Relocation of the Affected Villages with High Potential Risk The affected portions of villages to be relocated Required base to accommodate (ha) Shaolin ( 小林 ) Village 7.92 Namasia ( 那瑪夏 ) Township Ethnic Village Liouguei ( 六龜 )Township Wutai ( 霧台 )Township Ali Village, etc Fangliao ( 枋寮 )Township, etc Majia ( 瑪家 )Township 15.44

18 35 Comprehensive River Basin Management Land use with disaster risk reduction Flooding vulnerability map 氣候雨變遷加降( 降雨強) 強風暴潮潮汐(潮汐擋抽排 ( 堤防 ) ( 閘門 ) ( 抽站 ) 排滯調洪入滲擋排疏分洪逕流蓄泛洪入滲 ( 補注 ) 涵養 ( ) 海上升)地下補注地下補注海海洋潮汐(海岸河口平地都市化地區 ( 鋪面化 ) ( 都市鄉鎮 ) 河川排系統滯洪調洪設施脆弱性增加恢復力降低平原農田 ( 田 ) 果園塘湖河流灌溉系統坡地丘陵林地旱田果園野溪庫山地 ( 森林 ) 集中降雨災害強度增強 Analysis of flood vulnerability with locality factors 氣象淹地層下陷社會經濟總人口彰雲嘉沿海地區高雄台南都會區高屏沿海區 IV Conclusions

19 37 Future Work 1. Enhancement of weather & disaster monitoring system Due to the complexity of weather and geography, investment on monitoring system is crucial to upgrade capability of observation. 2. Improving early-warning technology Quantitative estimation of rainfall for supplying basis of early warning. 3. Establishing integrated t platform for information exchange A platform which connects the information between central and locall governments, simplifying i administrative i ti procedures and updating automatically. 4SOPf 4. for emergency operation (1) Evacuation (2) Rescue (3) Quick recovery. 38 Future Work 5. Amendment of Disaster Prevention and Rescue Act ( 災害防救法修訂 ): Initial amendment was approved on Nov. 9 and will be sent for deliberation soon Establishment of Office of Disaster Prevention and Protection in cabinet level Active involvement of military sectors 6. legislation of Land Planning Act ( 國土計劃法 ): Draft was approved on Ot8 Oct. and will besent for legislation l soon 7. Comprehensive river basin management Four pilot projects including Danshuei River, Dajia River, Jhuoshuei River, and Gaoping River will be initiated to propose whole basin management. 8. Adaptation strategy to mitigate impacts of climate change Research and assessment of temperature deviation, sea-level rise, extreme rainfall, increasing intensity of tropical cyclone

20 39 Thank You for Your Attention!

Understanding disaster risk ~ Lessons from 2009 Typhoon Morakot, Southern Taiwan

Understanding disaster risk ~ Lessons from 2009 Typhoon Morakot, Southern Taiwan Wen Chi Lai, Chjeng-Lun Shieh Disaster Prevention Research Center, National Cheng-Kung University 1. Introduction 08/10