EFFECTS OF THE DECEMBER 2004 TSUNAMI AND DISASTER MANAGEMENT IN SOUTHERN THAILAND

EFFECTS OF THE DECEMBER 2004 TSUNAMI
AND DISASTER MANAGEMENT IN SOUTHERN THAILAND
Chanchai Thanawood, Chao Yongchalermchai and Omthip Densrisereekul
Faculty of Natural Resources
Prince of Songkla University
Hat Yai, Songkhla. 90110. Thailand.







ABSTRACT

A quake-triggered tsunami lashed the Andaman coast of southern Thailand on
December 26, 2004 at around 9.30 am local time. It was the first to strike the shorelines
of southern Thailand in living memory. Coastal provinces along the Andaman coast
suffered a total of 5,395 deaths – more than half of whom were foreign tourists, with
another 2,822 reported missing. Of the 6 affected coastal provinces, Phang Nga was the
worst-hit province with some 4,224 lives lost and 7,003 ha of land area devastated.
Takua Pa District, which was a prime tourist area with numerous beach resorts, was the
most severely affected area in Phang Nga Province.
Through the use of the aerial photographs and Ikonos images, it was found
that 4,738 ha of Takua Pa District’s coastal area were affected by the tsunami. The
tsunami run-up heights of 7-8, 5-7 and 10-12 metres, were observed at, respectively,
Ban Namkhem, Pakarang Cape and Ban Bangnieng in Takua Pa District. The tsunami
caused heavy damage to houses, tourist resorts, fishing boats and gear, culture ponds
and crops, and consequently affected the livelihood of large numbers of the coastal
communities. The destructive wave impacted not only soil and water resources, but also
damaged healthy coral reefs, sea grass beds and beach forests. The surviving victims
faced psychosocial stresses resulting from the loss of their loved ones, being rendered
homeless and fears of another tsunami. The tsunami effects on human settlements,
livelihoods, coastal resources, natural environment together with the psychosocial well
being of the coastal communities have contributed to the degradation of the coastal
ecosystems.
Following the 2004 event, it has become apparent that the country’s disaster
management strategies need to be strengthened through the implementation of
mitigation and preparedness options to enhance the community’s resilience to natural
events such as tsunami. The improved strategies are discussed in this paper.



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1. INTRODUCTION
Southern Thailand, also designated as Peninsular Thailand, lies between
latitudes 50 and 110 N, and longitudes 980 and 1020 E. It covers an area of 7,153,917 ha
and has over 2,705 km of shoreline. The mountain ranges form the backbone of this
region, with the western coastline facing the Andaman Sea and the eastern coastline
facing the Gulf of Thailand. Many so-call pocket beaches with short and narrow sandy
beach nestled between head lands are found along much of the Andaman coast,
whereas the Gulf of Thailand coast is characterized by long mainland beaches with
associated landforms such as barriers, spits and sand dunes (Sinsakul, 2004). The
peninsular area affords excellent access to the seas, with 12 of the 14 southern
provinces having sea access. Southern Thailand, in general, enjoys a tropical climate
that provides good moisture and humidity throughout the year. Its coastal areas are
diverse, and contain productive ecosystems that sustain a large proportion of the coastal
population, with plentiful flora and fauna. Pristine tropical rain forests on the uplands,
beach forests and soft white sand beaches along the coastal shores and stunning marine
life make Thailand’s southern region one of Asia’s top choice tourist destinations.
In response to the phenomenal growth of the tourism and fishery, including
aquaculture industries, tourist resorts, culture ponds, and aquaculture infrastructure
have replaced much of the mangrove and beach forests along the coastal shores (UNEP,
2005). Many of the coastal sand dunes that act as natural barriers against incoming
waves have been removed to make way for the construction of beach resorts, walkways
and roads. Most of the fisher folks and impoverished local populations that made a
living in tourist-related activities live in weakly-constructed and unplanned settlements
in low-lying areas close to the shores. As a consequence, the coastal areas of southern
Thailand have become highly vulnerable to the occurrence of natural disasters caused
by extreme events.
At 0059 GMT on 26 December 2004, a magnitude 9.3 earthquake ripped apart
the seafloor off the western coast of northern Sumatra, Indonesia. The sudden vertical
rise of the seabed by several meters during the quake displaced massive volumes of
water, resulting in a devastating tsunami. This seismic sea wave traveled thousands of
kilometers across the Indian Ocean, and ravaged the Andaman coast of southern
Thailand at 9.30 am local time. Coastal provinces including Phuket, Phang Nga, Krabi,
Ranong, Trang and Satun (Figure 1) suffered a total of over 5,395 deaths–more than
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Figure 1. Tsunami affected areas along the Andaman coast, southern Thailand.

half of whom were foreign tourists, with another 2,822 reported missing (Department
of Disaster Prevention and Mitigation, 2005). Of the 6 affected provinces, Phang Nga
was the worst - hit with some 4,224 lives lost and 7,003 ha of land area devastated.
Takua Pa District, which was a prime tourist area with numerous beach resorts, was the
most severely affected area in Phang Nga Province (FAO, 2005). In this district, the
tsunami destroyed lives, houses, livelihoods on a scale never before seen in Thailand.
As the Indian Ocean has several seismic sources, recurrence of the tsunami on
the scale of the 2004 event can be anticipated in the future. According to NGI (2006), a
tsunami generated by a magnitude 8.5 earthquake on the Sunda Arc would crash into
the Andaman coast of southern Thailand and cause major loss of life and destruction of
property again within 50-100 years.
The objective of this study were to (i) assess the effects of the December 2004
tsunami on the coastal ecosystem in Takua Pa District, the worst-affected area in the
tsunami tragedy, and (ii) provide recommendations for the strengthening of disaster
management strategies to enhance Thailand’s capacity to manage a natural catastrophe
of the nature and magnitude of the December 2004 event in the future.

2. MATERIALS AND METHODS

This study was based on both primary and secondary sources of data and
information. The primary data was obtained through interviews of eyewitnesses,
laboratory analysis of soil and water samples, measurement of tsunami run-up heights
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and interpretation of remotely sensed data and aerial photographs. The secondary data
included information on 2004 tsunami impacts from local government agency offices
and sub-district administrative organizations.
2.1 Materials

1) Topographic maps for the tsunami affected area on a 1:50,000 scale,
published by the Royal Thai Survey Department in 2000.

2) Colour aerial photographs for the tsunami affected areas on a 1: 25,000 scale,
acquired in February 2002, produced by the Royal Thai Survey Department.

3) Ikonos images, pertaining to the affected areas on a 1:4,000 scale, acquired
on December 30, 2004, provided by the Geo-Informatics and Space Technology
Development Agency (GISTDA).
2.2 Methods

In this study, Geographic Information Systems were used to develop two
digitized thematic maps, one which defined the tsunami-affected area boundary, and a
land use map of the tsunami devastated area. All GIS computation and coverage
overlays were performed with PC ArcInfo software. The boundaries of the area studied
were digitized from the 1:50,000 topographic maps. The tsunami affected areas were
digitized from a map visually interpreted from the 1:4,000 Ikonos images, acquired 4
days after the December 2004 tsunami event. Land use coverage in the area of concern
was generated in ArcInfo format by digitizing from land use maps visually interpreted
from the 1:4,000 Ikonos images. The 1:25,000 aerial photographs, acquired in 2002,
were used to assist in the classification of land use, and ground truthing was also
conducted to validate the final results. Land use types in the tsunami affected areas
were determined by overlaying land use coverage with tsunami affected area coverage.

Data on tsunami run-up heights were obtained through interviews of
eyewitnesses. Water marks on houses, building and trees provided additional data on
tsunami heights. To assess the effects of the tsunami on soil resources, three replicate
samples of soil were collected from the worst-hit agricultural area in Takua Pa District,
Phang Nga Province at 0-5 and 5-30 cm depths. The soil samples were air-dried, passed
through a 2 mm sieve, and analyzed for electrical conductivity (EC) and pH. In
addition, three replicate water samples were collected in 0.75 litre polyethylene bottles
from the middle of the water column of surface water in the tsunami affected
agricultural area in Takua Pa District. The samples were immediately analyzed for
dissolved oxygen (DO) using a dissolved oxygen meter. The rest of the water samples
were stored on ice and transferred to a laboratory for analyses of salinity and pH.

A field survey was also conducted to assess the impacts of the destructive waves
on the psychosocial well being of tsunami affected populations. Takua Pa District,
Phang Nga Province was selected for assessment as they experienced many and severe
psychosocial problems. Interviews were conducted in a participatory manner with
open-ended questions so as to allow the interviewees to guide the outcomes. A total of
128 surviving victims from two coastal sub-districts in Takua Pa District, namely, Bang
Mueng and Kuk Khak Sub-districts, were interviewed.

3. RESULTS AND DISCUSSION
Through the interpretation of the aerial photos and Ikonos images, it was found
that 4,738 ha of Takua Pa District’s coastal area were affected by the devastating
tsunami (Table 1). In this district, the affected areas stretched from the coastline of Ban
Namkhem, which is located in the north of Takua Pa District close to the border with
Myanmar, downward through Pakarang Cape in Ban Bangkaya, which are located in
the central part of the district, through Ban Bangnieng, and then to Khao Lak Merlin
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Resort, which is located on the coast in the southern part of the district. Of these
affected areas, 848 ha or 18.7% were agricultural land, 600 ha or 13.2% were beach
forests and 278 ha or 6.1% were urban and built up land (Figure 2 and Table 1). It
should be noted that only 7 ha of the mangrove forests in the district were impacted by
the tsunami (Table 1).
Based on the field visit, it was evident through interviews of eyewitness and
measurements of watermarks on houses, buildings and trees, that Ban Namkhem
suffered a tsunami run-up height of 7-8 metres. In this locality, the fishing


Figure 2 Land use in tsunami affected area in Takua Pa District.

Table 1 Land use types in tsunami affected areas in Takua Pa District.
Land use type
Tsunami affected area
Ha %
1. Urban and built up land
278
6.1
2. Mangrove forests
7
0.2
3. Beach forests
600
13.2
4. Mixed orchard
400
8.8
5. Perennial
316
7.0
6. Rubber
132
2.9
7. Fishery and aquaculture
63
1.4
8. Water bodies
468
10.3
9. Miscellaneous
2,276
50.1
Total 4,540
100.0

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communities, living in weakly-constructed houses near sea level, were completely
wiped out and lost two-thirds of their inhabitants in the tsunami tragedy. The powerful
wave washed away fishing boats and gear, destroyed culture ponds and damaged
aquaculture infrastructure. A couple of large fishing boats were even thrown violently
inland and deposited in a residential area of Ban Namkhem (Figure 3). At Pakarang
Cape, Ban Bangkaya, the maximum tsunami run-up measuring up to 5-7 metres was
observed. In this locality, intense beach erosion and severe damage to coral reefs and
beach forests were observed (Figure 4), and almost all the luxury hotels and fisher folk
villages in close proximity to the seashore lay in ruins. Agricultural land was salinated,
and wells and ponds were contaminated with intruding sea water. The powerful wave
also damaged coconut and oil palm plantations as trees were uprooted by the action of
the wave. The ravages of the destructive wave extended up to 2 kilometers inland.
The tsunami wave of 10-12 metres and inland penetration of wave of 1
kilometres badly damaged Ban Bangnieng, which is one of the important tourist
attractions south west of Pakarang Cape. Khao Lak beach, a newly constructed tourist
spot, suffered a run-up height of 8-12 meters. The beachfront hotels, tourist resorts and
tourism infrastructure along the shore were demolished. At this locality, approximately
half of the 400 guests in a luxury beachfront resort perished in the ground-floor rooms,
swamped by the force of the giant wave. The loss of life and damage to the property at
Khao Lak beach was extensive because the beach was surrounded by elevated ground
and hills. With run-up height of 5-6 metres, the tsunami also caused major loss of life
and destruction of infrastructure to Khao Lak Merlin Resort. At this locality, the trail of
destruction left by the devastating wave extended up to 1 kilometer inland.



Figure 3 A group of resort buildings lies in ruins (left) and a fishing boat rests on shore (right).




Figure 4 Views of the coastal shores in Takua Pa District after the 2004 tsunami.

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Prior to the 2004 tsunami, the tourism, fisheries and agricultural industries
provided most of the livelihoods in the affected areas along the Andaman Coast. The
tourism sector was the most important source of revenue and the biggest provider of
livelihoods (UN, 2006). As noted earlier, the field survey conducted after the tsunami
revealed that most of the beachfront hotels, tourist resorts and tourism infrastructure in
coastal areas of Takua Pa District were totally or partially affected by the catastrophe.
Following the powerful tsunami, the fishing industry, including coastal aquaculture,
suffered major losses in terms of fishing boats and gear, culture ponds, cages and
shrimp hatcheries, thus destroying the local economy.
It was observed during the field visit that the tsunami flooded costal areas up
to two kilometers inland. It traveled upstream through coastal estuaries and rivers,
extending the devastation well inland from the coast in these areas. Hence, deposition
of salts from intruding sea water in soil is expected to occur in the inundated areas. Of
seven soil samples collected from the worst-hit area in Takua Pa District in January
2005, six samples at 0-5 cm depths had high EC values (Table 2), rendered it unsuitable
for cultivation. Damaged crops included mixed orchards, rubber, oil palms and coconut
trees. Likewise, the water quality in wells, ponds and canals in tsunami affected coastal
areas was deteriorated due to sea water intrusion as well as sewage-related
contamination. Of the six water samples collected from the Takua Pa area, five samples
contained high salt levels (Table 3), thereby affecting irrigation options. The impacts of
the tsunami on the major economic sectors such as tourism, fisheries and agriculture
directly affected the livelihoods of the coastal population.


Table 2 Values of EC and pH of soil samples collected from Takao Pa District
Location Coordinates EC
pH


0-5 cm. 5-30 cm. 0-5 cm. 5-30 cm.
Ban Nam Khem 0419982 E 0979678 N
4.17
0.81
7.71
6.72
Ban Bangsak
0419390 E 0972754 N 13.94
8.28
8.14
8.66
Kuk Khak Beach 0419362 E 0976550 N 11.67
4.59
9.49
9.20
Ban Kuk Khak 0417119 E 0961439 N
8.28
3.12
8.66
8.73
Ban Pak Veep
0418509 E 0967451 N
6.36
0.83
7.93
6.96
Ban Bangnieng 0417409 E 0958291 N
3.21
2.40
9.13
7.86
Khao Lak Merlin 0416645 E 0948363 N 12.34
8.64
8.25
8.33

Table 3 Values of salinity, DO and pH of water samples collected from Takao Pa
District.
Location Coordinates
Salinity
DO
pH
(ppt)
(mg/l)
Ban Nam Khem
0419982 E 0979678 N
24.5
4.02
8.19
Ban Bangsak
0419390 E 0972754 N
17.9
6.75
8.35
Kuk Khak Beach
0419362 E 0976550 N
3.70
4.42
7.68
Ban Kuk Khak
0417119 E 0961439 N
24.8
7.17
8.62
Ban Bannieng
0417409 E 0958291 N
28.1
4.59
8.39
Khao Lak Merlin
0416645 E 0948363 N
32.9
4.90
8.06

The field survey also revealed that the December 2004 event also caused
substantial deterioration to the natural environment. The destructive wave damaged
healthy coral reefs, sea grass beds and beach forests along the impacted coastlines. It
was reported, however, that extensive areas of mangroves and other coastal forests had
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played an important role in mitigating the effects of the 2004 tsunami disaster (FAO,
2005). The catastrophe also caused significant geomorphologic changes along the
Andaman coastline, such as eroding sand beaches and enlarging the mounts of the
rivers to the sea (Figure 5). The devastating wave has in fact literally redrawn the
shorelines of the Andaman coast of southern Thailand.


Source : Space Imaging/crisp-Singapore.
Figure 5. Pakarang Cape before (left) and after (right) the 2004 tsunami, showing beach erosion.

Through interviews of surviving victims, it was found that the majority of
them faced a number of psychosocial stresses resulting from the loss of their loved ones
and community members, being rendered homeless, fearful of more tsunamis, suffering
from a loss sense of safety and security, and lost livelihoods. For those who survived
the tragedy, most of them suffered most from phobic disorders, followed by depressive
and anxiety disorders. It will take months and years to restore lives to pre-tsunami
levels of functioning. The interview results also showed that many tsunami victims,
whose houses were washed away, lost their land ownership right in the aftermath of the
tsunami disaster. These critical issues have led to a decline in the quality of life of the
affected coastal communities.
The adverse effects of the tsunami catastrophe on coastal resources, natural
environment, human settlements, and livelihoods together with a decline in life quality
values of the coastal population have contributed to the degradation of the coastal
ecosystems. There is therefore a profound need for a rehabilitation of the damaged
ecosystems to restore sustainable livelihoods to the people of the affected communities
in the coastal areas.
Most of the fatalities along the Andaman coast of southern Thailand can be
attributed to the government‘s failure to warn the coastal communities of the imminent
arrival of the tsunami. In fact, thousands of lives could have been saved had a tsunami
early warning system been established in the Indian Ocean (Alverson, 2005). Prior to
the December 2004 tsunami disaster, there was no operational tsunami warning facility
in place in Thailand because the kingdom had never been struck by a tsunami and this
type of catastrophic event was considered to be extremely rare in the area (Tibballs,
2005). However, it is still questionable as to how effective this would have been in
alerting the coastal communities of imminent danger in a country which has poor
communication systems and no awareness of the danger. The lack of precautionary
behavior of the coastal inhabitants, even when noticing the suddenly receding tide that
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provided a signal of the approaching tsunami, also contributed to the enormous loss of
life. It is essential, therefore, to emphasize the urgent need to strengthen and improve
disaster management strategies in order to enhance the country’s capacity to cope with
the impact of future tsunami disaster.

4. TSUNAMI MANAGEMENT STRATEGIES
Although the occurrence of an earthquake and ensuing tsunami cannot be
prevented, the magnitude of catastrophic impacts in terms of loss of life and
livelihoods, destruction of property and environmental damage can be kept within
reasonable limits through an integrated approach to disaster management. Planning for
disaster encompasses four different but related aspects, mitigation or prevention,
preparedness, response and recovery. In Thailand, however, disaster management has
primarily focused on the emergency period response and post-impact recovery.
Following the December 2004 tsunami disaster, it has become apparent that such an
approach is not sufficient to cope with the threat from the tsunami catastrophe. Much
greater emphasis should be given to mitigation and preparedness measures.
In response to the 2004 tsunami, the Thai Government directed the
establishment of the National Disaster Warning Centre to function as a centralized unit
receiving, monitoring, processing and relaying critical information pertaining to
impending natural disasters and issuing a public warning in such an event (UN, 2006).
The centre also acts as a national clearing-house of disaster risk management
information. In recognizing the fact that disaster response should be based not only on
the warning systems, the Thai government has adopted and implemented vulnerability
reduction programmes through work in two areas: disaster prevention and/or mitigation
to reduce an area’s susceptibility to the impact of the tsunami hazards, and
preparedness to build tsunami resilient communities. These programmes include the
following measures;


1. Mitigation measures.
1.1 Establishment of land use plan for coastal areas based on
vulnerability assessments and risk analysis. Critical facilities such as schools, hospital,
hotels or high occupancy buildings should not be built in vulnerable areas. Existing
tourism facilities, shrimp farms and aquaculture infrastructure located in areas at risk
should be relocated.
1.2 Provision of appropriate incentive packages and attractive livelihood
opportunities to encourage coastal communities to abandon settling in vulnerable
locations and/or living in poor-designed houses, particularly along low-lying areas of
the coast.
1.3 Maintenance of environmental and ecological stability of the coastal
areas through the enrichment of mangrove and beach forests to act as the first line of
defense from tsunami waves (Figure 6), and rehabilitation of lost and degraded coral
reefs and sea grass beds to help stabilize the coastline and prevent beach erosion.
1.4 Reconstructing removed coastal sand dunes and protecting the
remaining sand dunes to act as a barrier against giant waves. Creating buffer zones
along the coastlines to protect coastal communities from tsunami waves are established.
The buffer zones or green belts can be created through the establishment of buffer strips
of between 300-400 metres, planted with mixed vegetation.
2. Preparedness measures.
2.1 Installation of a local tsunami warning system, which includes siren
towers at popular and crowded beaches (Figure 6), and a tsunami warning sensor
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floating offshore in the most vulnerable provinces along the Andaman coastline, not
only to address the safety and security concerns of the coastal communities, but also to
establish southern Thailand as a safe destination for foreign tourists.

2.2 Development of education programme through school and university
curricula to educate vulnerable coastal communities about the nature and processes of
the tsunami hazard and how to protect themselves at the time of impact as well as the
importance of mangrove forests, beach forests and coastal sand dunes in mitigating
tsunami effects.

2.3 Formulation of a detailed plan for emergency evacuation of
vulnerable coastal communities as well as organizing evacuation drills in order to make
the appropriate response more of an instinctive reaction, requiring less thinking during
an actual emergency situation.

Figure 6 A tsunami warning tower (left) and re-planted beach forests (right) along the coastal shores.

2.4 Raising the awareness of coastal communities about the dangers
posed by a deadly tsunami. Brochures, posters, calendars, and announcements on radio
and television can be used to stimulate public awareness.
2.5 Construction of a tsunami memorial to commemorate areas
devastated by the 2004 tsunami. The memorial would become a major attraction for
both locals and visitors, helping them to understand the coastal geomorphology and
ecosystems of the Andaman coastline, and to remind them of the disastrous
consequences of the December 2004 tsunami events.
The disaster plans of action, including elements of disaster mitigation and
preparedness activities as well as responsible agencies are shown in Table 4. It is
essential that attention be given to coordinating and integrating mitigation and
preparedness activities implemented by various government departments and non-
governmental organizations so that the scarce resources available can be used in the
most effective and timely manner. Moreover, local community involvement in planning
and implementing the measures of hazard mitigation and emergency preparedness is
needed to ensure continued interest and support during the implementation stage.
In light of concerns about the recurrence of the tsunami disaster in southern
Thailand, more collaboration between international research communities to pool
resources, scientific knowledge and expertise should be encouraged so as to bring about
an increase in the capacities of the relevant authorities and vulnerable communities to
cope effectively with such eventualities. Examples of research topics that should be
undertaken are as follows;
1) Tsunami hazard assessment using Remote Sensing and GIS.
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Document Outline

• ACKNOWLEDGEMENTS
• REFERENCES

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