INTEGRATED FLOOD MANAGEMENTINTEGRATED FLOOD MANAGEMENTIN KOREAIN KOREA

SoontakSoontak LEELEE, , Ph.D., D.Sc., Hon.D.Eng.Sc.Ph.D., D.Sc., Hon.D.Eng.Sc.Distinguished Professor, Distinguished Professor, YeungnamYeungnam University, Republic of KoreaUniversity, Republic of KoreaPresident, International Hydrologic Environmental Society (IHES)President, International Hydrologic Environmental Society (IHES) andandKorea Federation of Water Science & Engineering Societies (KFWSEKorea Federation of Water Science & Engineering Societies (KFWSES)S)

SoonkabSoonkab CHUNGCHUNG, Ph.D., Ph.D.DirectorDirector--GeneralGeneral

Forecast Bureau, Korea Meteorological Administration Forecast Bureau, Korea Meteorological Administration Republic of KoreaRepublic of Korea

FLOOD CHARACTERISTICSFLOOD CHARACTERISTICS

JAN. FEB. MAR. APR. MAY JUN. JUL. AUG. SEP. OCT. NOV. DEC.

SpatialDistribution

1,000

1,689

Annual precipitation(mm)

Time Distribution of Precipitation

□□ The main typhoon season, which affects Korea, normally runsThe main typhoon season, which affects Korea, normally runsbetween June and September. Korea is normally hit directly between June and September. Korea is normally hit directly by 1by 1to 3 heavy typhoon storms per year with most events occurrito 3 heavy typhoon storms per year with most events occurring inng inAugust.August.

Distribution of PrecipitationDistribution of Precipitation

4437

28 26

107

52 49

26 2513

57

83

0

20

40

60

80

100

120

100.1~ 110 110.1~ 120 120.1~ 130 130.1~ 140 140.1~ 150 More than 150.1

Unit : mm

1992- 2001 1971- 1980

Number of Daily Rainfall Events

Rainfall Intensity has been increased significantly, especially Rainfall Intensity has been increased significantly, especially for higherfor higherintensity events.intensity events.

Characteristics of the Rivers in Korea(1/2)

□□ The river reaches are relatively short and channel slopes are reThe river reaches are relatively short and channel slopes are relatively steeplatively steep..

-- The river reaches are short and drainage areas are small in KorThe river reaches are short and drainage areas are small in Korea compared ea compared with other major continental rivers. with other major continental rivers.

-- The channel slopes are relatively steep upstream because of steThe channel slopes are relatively steep upstream because of steep mountains ep mountains and deep valleys in the uplands.and deep valleys in the uplands.

□□ Floods occur quickly and peak flood discharges are enormousFloods occur quickly and peak flood discharges are enormous..

-- Due to the topographical conditions and torrential rainfalls, tDue to the topographical conditions and torrential rainfalls, the hydrographs he hydrographs of rivers in Korea are very sharp and peak flood dischargof rivers in Korea are very sharp and peak flood discharges are enormous es are enormous compared with other comparable rivers in the continent.compared with other comparable rivers in the continent.

Korean River Basin CharacteristicsKorean River Basin Characteristics

□□ Flow variations are highFlow variations are high..

-- The coefficients of the river regime, expressed by maximum discThe coefficients of the river regime, expressed by maximum discharge over harge over minimum discharge for rivers in Korea usually range from minimum discharge for rivers in Korea usually range from 100 up to 700. 100 up to 700.

-- This large variation in the flow discharge causes serious problThis large variation in the flow discharge causes serious problems in river ems in river management concerning flood control and water use.management concerning flood control and water use.

Characteristics of the Rivers in Korea(2/2)

Korea Main River SystemHan River : 25,954 km2 / 494 km

- 3 Multi-Purpose Dams- 6 Hydro-Power Dam- 1 Flood Control Dam

Nakdong River : 23,384 km2 / 510 km- 5 Multi-Purpose Dams

Geum River : 9,912 km2 / 398 km- 2 Multi-Purpose Dams

Yeonsan River : 3,468 km2 / 137 km- 3 Irrigation Dams

Seomjin River : 4,960 km2 / 224 km- 2 Multi-Purpose Dams

Water, Water, Water … Flood

Flooded Paju City in 1998

Collapse of Yeoncheon Dam in 1996

Floods in a Recent Decade

Floods in a Recent DecadeRailway Bridge Broken by Typhoon Rusa in 2002

Village Flooded by Typhoon Maemi in 2003

Flood Damages

0

1,000

2,000

3,000

4,000

5,000

6,000

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Year

Pro

perty

Los

s in

mili

on U

S D

olla

rs

0

100

200

300

400

500

600

Life

Los

s

Property Loss Life Loss

FLOOD RISK FACTORSFLOOD RISK FACTORS

Risk Factors (1/4)Risk Factors (1/4)

□□ Abnormal weather events due to global warmingAbnormal weather events due to global warming

□□ Rapid urbanization and industrializationRapid urbanization and industrialization

□□ Insufficient infrastructure for flood defenseInsufficient infrastructure for flood defense

□□ Lack of social systems, cooperation between sectors andLack of social systems, cooperation between sectors andpublic participationpublic participation

Risk Factors (2/4)Risk Factors (2/4)

Air temperature has risen significantly,Air temperature has risen significantly,higher than global average higher than global average

Annual Average Air TemperatureAnnual Average Air Temperature

Rainfall Intensity has been increasedRainfall Intensity has been increasedsignificantly, especially for higher significantly, especially for higher intensity events intensity events

Number of Daily Rainfall EventsNumber of Daily Rainfall EventsAbnormal weather events Abnormal weather events due to global warmingdue to global warming

Risk Factors (3/4)Risk Factors (3/4)

74.474.487.687.6483.8483.847,36047,36099,80099,80019991999

70.270.281.981.9178.8178.843,41043,41099,27499,27419901990

65.865.868.768.737.837.837,44037,44098,99298,99219801980

63.263.250.150.12.82.831,47031,47098,22298,22219701970

52.452.439.139.10.20.224,99024,99098,22298,22219601960

AverageAverageLife(yearLife(year))

UrbanUrbanRatio(%)Ratio(%)

GDPGDP(trill. Won)(trill. Won)

PopulationPopulation(thousand)(thousand)

Area(kmArea(km22))IndexIndex

YearYear

Social System IndicesSocial System Indices

For the last four decades, population increase two times; GDP inFor the last four decades, population increase two times; GDP increased 2,500creased 2,500times; and urban ratio increased more than two times.times; and urban ratio increased more than two times.

Rapid urbanization and industrializationRapid urbanization and industrialization

Risk Factors (4/4)Risk Factors (4/4)

□□ Lack of fund for flood controlLack of fund for flood control

□□ Difficulty in securing investment funds for middle and smallDifficulty in securing investment funds for middle and small--sized streamssized streams

□□ Insufficient flood control facilities in urban areasInsufficient flood control facilities in urban areas

□□ Deficient improvement of stream management systemDeficient improvement of stream management system

□□ Deterioration of stream functionsDeterioration of stream functions

Insufficient infrastructure for flood defenseInsufficient infrastructure for flood defense

INTEGRATED FLOODINTEGRATED FLOODMANAGEMENTMANAGEMENT

Flood Forecasting and WarningFlood Forecasting and Warning

□□ Concept of Flood Forecasting and Concept of Flood Forecasting and WarningWarning

-- Storm monitoring and forecastingStorm monitoring and forecasting

-- Flood information monitoring andFlood information monitoring andtransmittingtransmitting

Ministry ofConstruction and

TransportationRegional FloodControl Office

MOCTRegional Bureau

Detentionreservoir

RegionalAdministr

ativeOffice

⊙ Innovation toward creating forecast system

- Spatio-temporally detailed forecast

- Quantitative values for Socio-economically applicable products

- Weather forecast services going along with IT-ERA

- Enhance application potential of forecast products

application for partners, satisfaction for customers

⊙ Integration of Korea Meteorological Administration

Scientific knowledge and technologies for construction

digital forecast

Quantitative forecast for 12 watershed forecast elements every hours out to 48 hours based on 5 km grid scale over the Korea penisula.

RAINFALL FORECAST- KMA DIGITAL FORECAST -

1. Use numerical weather prediction output

5. Distribute digital forecast contents from DB system

2. Generate 5 km digital forecast grids DFS

DB

WO

RDED

IMAGE GRAPHIC

TIME-SERIES

TABULAR

VOICE

GRID-PO

INT

4. Edit temporal and spatial modification by forecaster

CONFIGURATION OF DIGITAL FORECAST SYSTEM (DFS)

- ADVANCED HYBRID FORECAST SYSTEM -3. Apply statistical forecast

model to specific stations

WHERE?WHEN?

HOW MUCH?

Benefits of Hydro-meteorological Forecast

USAGEProvide the best support for national water resources decision makers for drinking, washing, and agricultural information

→ AGRO-METEORLOGICAL FORECAST

PRESERVATIONProvide forecasts in exchange for reservoir scheduling information to produce hydrologic forecast

→ HYDROLOGICAL FORECAST

• Timely and accurate forecasts, and warnings

• Detailed forecast information to protect life and property

⇒ Enhanced the national economy using hydro-meteorological information

PREVENTIONProtect life and property from the threat of weather-related disasters Provide sufficient warning time to the communities

→ RIVER & FLOOD FORECAST

HOW TO USE WATER RESOURCE AND WATER ENVIRONMENT

• IN NATURAL SYSTEM

• TO NATURAL DISASTER

• FOR PUBLIC UTILITIES

TRACKING OFPRECIPITATION AREA

EVAPORATION

PRECIPITATIONEVAPOR-

TRANSPIRATION

WATER-CYCLE

SOIL WATERWATER

TRANSPORT

STREAM FLOW

Flood Forecasting and WarningFlood Forecasting and Warning

Minister of Ministry ofConstruction & Transportation

Administrator of Dam· To make plans for releasing water from dam

· To start releasing water

Flood Control Office· To estimate possible outflow by divided basin areas

· Flood forecast· Announcement and cancellationof flood forecast

TelemeteringObservation Station

· Monitoring Stations for waterlevel and rainfall

· Water level of dam and volumeof release

Central Disaster Prevention and SafetyCountermeasures Headquarters

Announcement to the Public(through broadcast or newspaper)

Related Agencies

Regional Disaster Prevention and Safety Countermeasures Headquarters

in Cities or Provinces

Residents in the regions

Notification of plansNotification of plansfor releasing waterfor releasing waterfrom damfrom dam

Notification ofNotification offloodflood--forecastingforecastingannouncementannouncement

Notification of resultsNotification of results

Report of resultsReport of results

ApprovalApprovalfor releasingfor releasingwater fromwater fromdamdam

Request of approvalRequest of approvalfor releasing waterfor releasing waterfrom damfrom dam

Flood Forecasting System (KFWMS)Flood Forecasting System (KFWMS)

Real-Time Monitoring System

Flood Forecast Module

Hydrologic Database System

River Selection Option

Flood Forecasting SystemFlood Forecasting System

Flood Management with Radar SystemFlood Management with Radar System

Flood Control Flood Control Pr

oced

ures

Proc

edur

es

Rainfall ForecastRainfall Forecast

Runoff AnalysisRunoff Analysis

Inflow EstimationInflow Estimation

Reservoir Operation SimulationReservoir Operation Simulation

Decision MakingDecision Making

Gate Opening & ReleasesGate Opening & ReleasesDam Upstream

Dam Downstream

Flood Control Procedure (1/2)

Field Office

WROCWROC

Video Video ConferencingConferencing

Flood ReleasesFlood Releases

Proc

edur

esPr

oced

ures

Rainfall ForecastRainfall Forecast

Runoff AnalysisRunoff Analysis

Inflow EstimationInflow Estimation

Reservoir Operation SimulationReservoir Operation Simulation

Decision MakingDecision Making

Gate Opening & ReleasesGate Opening & Releases

Flood Control Procedure (2/2)

Analysis for downstream Reduction of Water Level

ForecastingForecasting

Analysis for UpstreamAnalysis for Upstream Flood Control of DamFlood Control of Dam

Flood Control AssessmentFlood Control Assessment

SurveySurvey

Inundation AnalysisInundation Analysis

Scenarios /Scenarios /Flood RoutingFlood Routing

Map/UseMap/Use

Flood Hazard MapFlood Hazard Map

Flood Map SystemFlood Map System

BasinwideBasinwide Comprehensive Integrated Flood Comprehensive Integrated Flood Management PlanManagement Plan

ObjectivesObjectivesBy 2007, completing the By 2007, completing the BasinwideBasinwide Integrated Flood Management Plans for theIntegrated Flood Management Plans for the13 river basins in the nation to defend the flood from the extre13 river basins in the nation to defend the flood from the extreme rainfall;me rainfall;

-- Upgrade the flood management paradigm for the abnormal climate Upgrade the flood management paradigm for the abnormal climate changechange

-- Overcome the deficiency of flood control capacities due to the Overcome the deficiency of flood control capacities due to the limitationlimitationof dam construction and river flood protection facilitiesof dam construction and river flood protection facilities

-- Raise the storage capacities of flood in the basin Raise the storage capacities of flood in the basin

-- Establish the measures for the urban population and properties Establish the measures for the urban population and properties in the floodin the floodprone areasprone areas

-- Establish the integrated optimal operation system of dams and fEstablish the integrated optimal operation system of dams and flood controllood controlfacilities in each basinfacilities in each basin

Main contents (Basic direction) (1/2)Main contents (Basic direction) (1/2)

-- Distributing flood control functions into both river channel anDistributing flood control functions into both river channel and basin for the d basin for the present and future flood flow by changing the flood control ppresent and future flood flow by changing the flood control policy.olicy.

-- Increasing the flood storage capacities in upstream areas by thIncreasing the flood storage capacities in upstream areas by the construction e construction of riverside detention reservoirs or by using floodplain areasof riverside detention reservoirs or by using floodplain areas, and accordingly,, and accordingly,increasing the safety level of flood management in whole riveincreasing the safety level of flood management in whole river basin and r basin and decreasing the flood control volume in downstream channel readecreasing the flood control volume in downstream channel reach.ch.

-- Spatial and master planning for the flood control including stoSpatial and master planning for the flood control including storages, rainwaterrages, rainwatercapture systems, levees, pumping stations and capture systems, levees, pumping stations and landuselanduse plan for their plan for their construction and share of flood flow.construction and share of flood flow.

BasinwideBasinwide Comprehensive Integrated Flood Comprehensive Integrated Flood Management PlanManagement Plan

Main contents (Basic directionMain contents (Basic direction) ) (2/2)(2/2)

-- Planning, development and maintenance of optimal integrated opePlanning, development and maintenance of optimal integrated operationrationsystem for the flood controlsystem for the flood control

-- Building flood control plans of both structural and nonstructurBuilding flood control plans of both structural and nonstructural measuresal measuresappropriate to the regional characteristicsappropriate to the regional characteristics

-- Examining the links with higher level or other related plans asExamining the links with higher level or other related plans as well as thewell as thelinks of the facilities with other infrastructures such as railinks of the facilities with other infrastructures such as railways, roads andlways, roads andbridgesbridges

BasinwideBasinwide Comprehensive Integrated Flood Comprehensive Integrated Flood Management PlanManagement Plan

Control of Flood DisastersControl of Flood Disasters

Stream channel+Basin

Extreme Flood

Stream ChannelDesign Flood

Excess Flood

Basin-wideComprehensive Integrated Plan

Non-structural Measure

River Improvement

Basic Plan

Structural Measure

Allocation Measure PlanningFlood Scale

BasinwideBasinwide Comprehensive Integrated Comprehensive Integrated Flood Management PlanFlood Management Plan SatelliteSatellite

Rainfall Rainfall GaugeGaugeStationStationWater LevelWater Level

Gauge StationGauge StationForestForest

ManagementManagementProjectProject

MultipurposeMultipurposeDamDam

Dam ControlDam ControlOfficeOffice

BankBankFlood ControlFlood Control

OfficeOffice

Pumping Pumping StationStation

DrivingDrivingChannelChannel

Super BankSuper Bank

StormwaterStormwater ReservoirReservoirOf Seepage WaterOf Seepage Water

WetlandWetland(Flood Control &(Flood Control &

Water Purification)Water Purification)

Break waterBreak water

BankBank

SeewallSeewall

ParkingParking(storage)(storage)

PlaygroundPlayground(storage)(storage)

Agricultural LandAgricultural Land& Unused Land& Unused Land

LandslideLandslidePreventionPrevention

ProjectProject

ErosionErosionControlControl

DamDam

RainfallRainfallRaderRader

THANK YOUTHANK YOU

FORFOR

YOUR ATTENTION!!YOUR ATTENTION!!