Recent flood in South Korea and some efforts Prof. SeongJoon KIM. Konkuk University

Transcription

1 Recent flood in South Korea and some efforts Prof. SeongJoon KIM Konkuk University Dept. of Civil and Environmental System Engineering Contents Recent happenings Climate change evidence in SK Some tasks- did & to do Structural enforcement - preparation Information system early warning Big data - response Concluding remarks 1

2 Spring & Autumn periods are shortening. Winter & Summer seasons get intense cold & hit. China Korea Japan Temperature -2.9 Precipitation 76.6 mm Temperature 9. Precipitation 21. mm Winter (December - February) Summer (June - August) Four Seasons Spring (March - May) Autumn (October - November) Temperature 21.7 Precipitation 72.6 mm Temperature 11.2 Precipitation 23.7 mm Crops of four seasons in South Korea Spring (March to May) potato, green peas, corn, cabbage Summer (June to August) rice (.892 Mha), red pepper (44,8 ha), cucumber, pumpkin Autumn (September to November) radish, spinach, cabbage Winter (November to February) wheat (12, ha), garlic, onion 2

3 Present Water Resources Potential of South Korea Potential Amount of Water Resources 1,297 (1%) (211, Unit: 1 million m3 /year) Streamflow 73 (8%) Losses 44 (42%) Flood Discharge 6 (43%) Regular Streamflow 193 (1%) Discharge to Ocean 42 (32%) Direct Use of River Water 18 (8%) Use of Reservoir Storage 188 (1%) Use of Groundwater 3.7 (3%) Total Water Use 333 (26%) (Water Vision 22, 211) Agricultural Reservoirs in SK Concrete 13 Type Local gov 14,323 Earth 14,219 Etc 1 Managers Scale Total 17,31 Local gov. 14,17(81%) KRC 3,36(19%) Eff. storage: 2.78 bi. Ton covers % of agricultural water supply below.1 mi. Ton 1,494 between ,92 over 1. mi Ton 44 Construction year before 194 9, , ,96 after (2.%) (22.2%) (22.6%) ( 3.3%) MAFF 212 Statistical book 3

4 Multipurpose dam (1) Water supply: 1,883 million m3 /yr Flood control: 2,198 million m3 Agricultural reservoir (17,649) Water supply: 2,742 million m3 /yr (2 % of multipurpose dam) Storage Below 1, Ton Below 1, Ton Below 3, Ton Above 3, Ton 8 Recent happenings by flood 4

5 Annual Precipitation: 1,24 1,441 mm/yr 16 % increase after 2 Seoul metropolitan region, Heavy rain Typhoon Maemi Typhoon EWINIAR Gwangwon-do Drought Seoul, Heavy rain 21~22 23~24 2~26 27~28 29~21 211~212 Typhoon Rusa Typhoon Nabi Typhoon NARI Busan city, Heavy rain Seoul metropolitan region, Heavy rain Status of Recent Floods & Droughts in Korea Reservoir Collapses by Typhoons and Heavy rains April.24 mi Ton / Aug 21 6, Ton / Aug 27 44, Ton 17 mm within 1 hr

6 Big rain frequency increased since times 1 (81~1) Above safe 2 (61~8) Safe 3 (41~6) Normal 4 (21~6) Dangerous (~2) Very dangerous Flood risk 1994~2 21~21 3.6% (3 districts) increased (Water KONKUK Vision 22, UNIVERSITY 211) 6

7 13 Climate change evidence in SK Precipitation trend during over 38 yrs records (27 NK, 8 SK) Change ratio 42 N 41 N 39 N 38 N 36 N 3 N Annual precipitation amount E 126 E 128 E 129 E 131 E 142 N 41 N 39 N 38 N - 36 N Annual no. of prec. days N E 126 E 128 E 129 E 131 E N. 41 N 39 N 38 N N 3 N -1 Average rainfall intensity 124 E 126 E 128 E 129 E 131 E from Kwon (213) 7

8 from Kim, GS (26) from Kwon (21) 8

9 Future annual ave. rainfall intensity Present: 4-8 mm intensity Future: -12 mm intensity 44 N 44 N 44 N N 42 N N N 4 N 38 N 38 N 38 N N 36 N N 36 N N 34 N 34 N E 126 E 128 E E 13 E Base scenario (1976-2) 126 E 128 E 13 E 124 E 126 E 128 E 13 E -2 RCP 8. scenario-base scenario RCP 8. scenario ( ) from Kwon (213) Future 1 yr frequency rainfall Present: 1-3 mm range Future: 2-3 mm range flood risk highly increase 44 N 3 44 N 42 N 2 42 N 4 N 2 4 N 3 44 N N N 38 N 1 38 N 36 N 1 34 N 124 E 126 E 128 E 13 E Base scenario (1976-2) 36 N 34 N 124 E 126 E 128 E 13 E RCP 8. scenario ( ) -138 N N N E 126 E 128 E 13 E - RCP 8. scenario-base scenario from Kwon (213) 9

10 2 Some tasks did & to do 1

11 Reinforcement of Design Flood Standard times of 1 yr frequency rainfall times of 2 yr frequency probable flood 22 Choose largest value among 2 yr probable flood, historical maximum flood, regional maximum flood (2% add for Fill dam case) Apply PMF over mi Ton Level up freeboard height of emergency gate and release way KRC, 21 Reservoir water level monitoring projects Since 21, total 1,7 sites, effective storage above.1 million ton The project is almost finished Watch reservoir and alert flood and control storage water for drought from KRC headquater Open the real-time information at website 11

12 Real-time Agricultural Reservoir Flood Warning System is Now on Operation (KRC) TM/TC (Tele-metry & Tele-control) projects Since 21 to 221 The project will be continued to 221 with total $. billion Watching flood and managing drought by ICTbased monitoring and controlling irrigation & drainage facilities. Until now (214) introduced to 37 irrigation districts 12

13 TM/TC components Meteo. Obs. Relay Main station data collection, processing status display control instruction alarm notice inflow water level intake release alarm system rainfall temp. humidity wind speed etc. Water Source Canal RTU data transmission manipulation command Regulating reservoir gate opening, water level, discharge Chung-ju TM/TC 3 years, $2 million 2 main stations 28 tele-control gates 3 water levels 13

14 The agricultural reservoir embankment rehabilitation project Since 29 to 21, total 113 agricultural reservoirs, $2.7 billion As part of the four major river restoration project in South Korea The project is still on going to secure additional water for flood and drought prevention including streamflow management & water front development By the Korea Rural Community Corporation (KRC), securing total.28 billion tons Bank elevation Less than m 47 sites, raise Additionally Secured Water Before After Present 기존단면 New Toe Drain m to 1 m 36 sites, build big one Additionally Secured Water New Present Over 1 m 13 sites, build new one Present Additionally Secured Water 점토재 New Toe Drain 14

15 Farmland remodeling Before After 1

16 Radar Rain X-net Radar system for rural area is recommended 3 mins Khanun : Bolaven : Sanba : Spatial identification & tracking Discharge Soil saturation 32 16

17 33 Concluding remarks Risk management of Flood is the way for sustainable development of Rural Society 17

18 KRC needs continuous investment for flood management Paradigm shift with reservoirs Increasing reservoir storage by agricultural reservoir embankment rehabilitation project Automated water management system (TM/TC) Multiple water supply (irrigation and environmental flow) Global warming (climate change) Water level management (operation rule) Reinforced facility (spillway and gate) Reinforcement design criteria (2yr2%) Flood protection and control For stable Smart Water Grid, Precision Agriculture, Urban Agriculture 18