Ministry of Government Administration and Home Affairs

Republic of Korea

Country Report

 

CONTENTS

1. Organizations for Disaster Mitigation *

2. Disaster Statistics and Flood Damage in 1998 *

2.1. Statistics of the Last 10 Years *

2.2. Flood Damage in July and August, 1998 *

2.2.1. Introduction *

2.2.2. Hydrological Condition of Korea *

2.2.3. Characteristics of Rainfall between July 31 and August 18, 1998 *

2.2.4. Summary of the Flood Damage *

2.2.5. Conclusions *

2.3. Summary *

3. Disaster Prevention and Preparedness Activities *

3.1. Implementing the Disaster Prevention and Preparedness in 1998 *

3.2. Disaster Prevention Education, Drills, and Public Relations *

3.3. Implementing the Disaster Prevention Plan *

3.4. Risk Assessment Evaluation System of Disaster Impact(RAESDI) *

3.5. Implementing the Improvement of Disaster Prone Areas *

3.6. Implementing the Improvement of Small Rivers *

3.7. Establishment of Automatic Rainfall Warning Systems *

3.8. Management of Disaster in 1998 *

3.9. National Institute for Disaster Prevention *

4. Plans for 21st Century *

4.1. Refinement and Consolidation of Related Regulations *

4.2. Investment on River Side Infrastructures for Disaster Mitigation *

4.3. Systematic and Scientific Researches for Disaster Prevention *

4.4. Active International Cooperation *

 

 

 

 

1. Organizations for Disaster Mitigation

 

 

 

 

 

 

 

 

 

2. Disaster Statistics and Flood Damage in 1998

2.1. Statistics of the Last 10 Years

 

Table 1 Natural Disaster Damages for the Last 10 Years

item

 

year

Casualty

Evacuated

Person

Inundated

Area

Building

Ship

Farmland

Public

Facilities

Others

Total

(person)

(person)

(ha)

(106 $)

(106 $)

(106 $)

(106 $)

(106 $)

(106 $)

1988

143

5,053

17,987

0.5

1.2

8.8

69.0

22.1

101.6

1989

307

92,593

121,060

4.9

4.4

12.2

170.2

266.7

458.4

1990

257

203,314

124,276

7.7

2.5

37.4

230.2

263.5

541.3

1991

240

29,573

61,173

4.1

1.8

32.0

247.9

36.5

322.4

1992

40

965

13,969

0.1

0.9

1.2

12.5

5.4

20.0

1993

69

13,779

58,489

1.0

8.8

8.4

127.8

18.2

164.3

1994

72

11,852

6,275

0.5

3.7

9.1

72.2

42.3

127.8

1995

158

30,408

79,253

4.1

5.8

50.9

361.9

78.2

501.0

1996

77

18,686

47,968

12.5

0.7

45.1

278.8

65.5

402.5

1997

38

6,296

45,774

1.6

2.3

9.3

121.9

24.0

159.1

Total

1,401

412,519

576,223

42.2

37.2

243.6

1933.2

997.0

3253.3

Average

140

41,252

57,622

4.2

3.7

24.4

193.3

99.7

325.3

 

2.2. Flood Damage in July and August, 1998

      1. Introduction

A global anomaly in the atmospheric circulation has been caused by the effect of El Niño this year. The effect was revealed by heavy rains in some regions, especially in Japan, Korea, and Yangtze River area in China. In Korea, there were intensive heavy rains at most parts of the country between July 31 and August 18, 1998, due to the climatic disturbance and humid air inflow from Yangtze River area. The intensive rains caused wide spreading floods, which resulted in over 300 in deaths. More than 180 thousand residents were evacuated and the total property damage was more than about $923 million because of the floods. The direct cause of the floods was unusually high hourly precipitation.

During the floods, the damage was collected by local government offices and reported to Korea National Disaster Prevention and Countermeasures Headquarters (KNDPCH) where rapid damage analyses and proper counteractions were conducted. Also, Korea National Institute for Disaster Prevention (KNIDP) and other organizations performed damage investigations including aerial photographing on flooded areas.

 

2.2.2. Hydrological Condition of Korea

Korea is located in a monsoon region and experiences several Typhoons every year. The annual average precipitation is about 1,274 mm, and most of the precipitation occurs during the rainy summer season between June and September. River reaches in Korea are relatively short and the channel slopes are relatively steep. Therefore, flooding occurs quickly and the peak discharge is high due to the topographical conditions and the torrential rainfall. The flow variations also are very large and the coefficient of the river regime, expressed by the maximum over minimum discharge, usually ranges from 100 to 700.

 

2.2.3. Characteristics of Rainfall between July 31 and August 18, 1998

The "August Flood" was caused by localized and sudden rainfalls which had nicknames like "football" (unpredictable where to move) or "guerilla" (unpredictable when to appear). In fact, heavy rains appeared suddenly in various places in Korea such as Seoul, Kanghwa, Phaju, Tongduchon, Uijungbu, Sangju, Uisung, Pouen, Gurye, Soonchon, and etc.. Precise forecasting for this kind of sudden rain was almost impossible, and Korean Meteorological Agency is trying to provide more accurate weather forecasting adopting a supercomputer. Also, more damage was added by condensed precipitation over a short period of time, especially in mountainous and/or agricultural area.

 

Unusual characteristics of the "August Flood" can be found when observe the precipitation logs of Kanghwa, Seoul, and Soonchon areas. A total rainfall of 481 mm was accumulated in Kanghwa for just 11 hours on August 6, 1998, which was more than 47 day precipitation (400 mm) in the area this summer. This is the highest record of daily precipitation in August since Korean Meteorological Agency starts the recording in 1904. The second highest record in August is 439 mm in Pusan area August 23, 1991. Regardless of the month, Changheung has the highest daily precipitation record of 547 mm, and the second place goes to Puyeo with 518 mm. Even though Kanghwa is the third highest based on the daily precipitation record, the amount of rainfall between 10 p.m. August 5 and 6 a.m. August 6 indicates that it is no less than the highest record.

 

Soonchon, on the other hand, had a record-breaking hourly precipitation of 145 mm at 9:50 p.m. July 31. The previous hourly record was 119 mm in Seoul August 5, 1942. 10-minute rainfall of Soonchon area, 43 mm, was close to the highest record of 47 mm recorded in Seoul on June 22, 1956

 

In Seoul on August 8, a total precipitation of 333 mm was recorded which was the second highest following 355 mm on August 2, 1920. Table 2 shows the result of rainfall frequency analysis of August 1998 for Seoul and Kyungi Area.

 

 

Table 2 Rainfall Frequency Analysis of August 1998 for Seoul and Kyungi Area

AREA

1 HOUR*

2 HOURS*

6 HOURS*

24 HOURS*

NOTE

P (mm)

R(year)

P (mm)

R(year)

P (mm)

R(year)

P (mm)

R(year)

Kanghwa

112.0

150

216.5

1000

466.5

1000

619.5

1000

E

Uijungbu

99.0

60

190.0

600

340.0

1000

406.5

100

E

Tongduchon

86.5

30

144.0

90

242.5

200

354.3

40

I

Inchon

61.0

10

80.0

5

93.4

5

157.7

5

I

Seoul

60.5

10

99.0

10

173.0

20

361.5

50

I

note: * Duration, P = Precipitation, R = Return Period, E = Extrapolation, I = Interpolation

 

It can be shown that for Kanghwa and Uijungbu area the total amounts of precipitation well exceed the return period of 20 years for designing drainage system, and the design frequency of 100 years for urban stream construction. It also can be seen that there was a severe local variation. The differences in precipitation were quite big, although the measuring points were close each other.

 

2.2.4. Summary of the Flood Damage

The flood damage occurred between July 31 and August 18 was severe, and the pattern of damage was somewhat different from previous ones. Most parts of Korea, except Cheju Island, suffered great losses by the flood. According to KNDPCH the total property damage was more than about $923 million that is the second severest in the history. The first one is $1.1 billion (corrected for current value) which occurred in July 1987 by Typhoon Thelma.

 

More than 88 thousand buildings and 71,500 ha have been submerged and 7,413 homes were evacuated. The total damage was more than twice of average yearly damage. Figure 1 presents submerged areas and property damages between 1977 and 1998.

Figure 1 Submerged Areas and Property Damages between 1977 and 1998

286 people were dead and 38 were missing. This is the most severe one in the last 10 years. Most people were dead because of landslide in Kyungi area and Flash flood in Chiri mountain area.

 

In general, a disaster area is declared when the damage is more than about $900 thousand, $600 thousand, or $350 thousand in capital, urban, or local area, respectively. Regardless of administrative district, a town with a population of more than 300 thousand is declared as a disaster struck area when the damage is more than $600 thousand. During the "August Flood", 107 places were declared as disaster areas and Figure 2 shows their locations and relative position of Korean peninsula.

 

The percentages of the damage for individual facility or structure are shown in Figure 3. The largest damaged item is "River" which is almost 20% of total damage. Next items follow as "Road" (14%) and "Creek" (12%).

 

      1. Conclusions

Because of the flood occurred between July 31 and August 18, 1998, the total property damage was more than about $923 million that is second severest in the Korean history. It is pointed out that citizens should have more responsibilities for their own lives and the government should have more comprehensive countermeasures for disaster prevention. The "August Flood" warned us that the flood management is a very essential part of disaster mitigation and that we should be prepared for next big ones. Moreover, after analyzing the causes of the damage precisely, extensive river disaster counterplan needs to be addressed.

 

 

Figure 2 Locations of Disaster Areas by the "August Flood" and Relative Position of the Korean Peninsula

 

2.3. Summary

 

 

 

Table 3 Total Damages caused by Natural Disaster during the Period from Sep.

    in 1997 to Aug. in 1998

Classification

Units

Sep.- Dec., 1997

Jan. - Aug., 1998

Total

Casualties

(Dead or Missing)

Person

15

327

342

Evacuated Person

Family/

Person

910/3,460

7,686/25,481

8,596/28,941

Farmland Lost

or Buried

ha

2

7,978

7,980

House Destroyed

or Damaged

Unit

2

2,917

2,919

Property Damage

U.S.

$ million

16

1,006

1,019

 

3. Disaster Prevention and Preparedness Activities

3.1. Implementing the Disaster Prevention and Preparedness in 1998

To reduce the loss of life, property damage, and economic disruption caused by natural disasters such as floods and windstorms during the rainy season, the Korean government has designated the period from March 1 to May 31 in 1998 as "Disaster Preparedness Period" and performed several programs during this period.

 

a. Inspection and Maintenance of the Disaster-Prone Areas

 

b. Inspection and Maintenance of Large-Scale Construction Sites

 

c. Inspection and Maintenance of Disaster Prevention Facilities

 

 

d. Securing Equipment and Facilities for Emergency Countermeasures

The equipment and facilities for emergency countermeasures had been secured based on the average amount needed in the last ten years.

 

e. Saving Fund for Natural Disaster Countermeasures

 

 

3.2. Disaster Prevention Education, Drills, and Public Relations

a. Disaster Prevention Education

 

b. Drills and Practice Emergencies

 

 

c. Public Relation for Disaster Prevention

 

Inspection of disaster prevention facilities and equipment

Drill and campaign for disaster prevention

Photo display of disaster-struck areas and their recovery processes

Contest for disaster prevention posters

 

3.3. Implementing the Disaster Prevention Plan

 

 

 

3.4. Risk Assessment Evaluation System of Disaster Impact(RAESDI)

 

 

3.5. Implementing the Improvement of Disaster Prone Areas

 

 

3.6. Implementing the Improvement of Small Rivers

 

3.7. Establishment of Automatic Rainfall Warning Systems

During the summer season there have been casualties in valleys and riverbanks because of heavy rains. Automatic rainfall warning systems, which can detect the amount of precipitation in upstream, is being established at 108 sites from 1996 to 2003, so that campers can take early warning.

 

 

3.8. Management of Disaster in 1998

 

 

 

 

 

3.9. National Institute for Disaster Prevention

 

 

4. Plans for 21st Century

4.1. Refinement and Consolidation of Related Regulations

 

 

 

4.2. Investment on River Side Infrastructures for Disaster Mitigation

 

4.3. Systematic and Scientific Researches for Disaster Prevention

 

4.4. Active International Cooperation