DAMAGE ASSESSMENT FOR PARTS OF ANDAMAN AND NICOBAR ISLANDS (CASE STUDY: 2004 TSUNAMI AND EARTHQUAKE EFFECT ONANDAMAN AND NICOBAR ISLANDS)

1. DAMAGE ASSESSMENT FOR PARTS OF
ANDAMAN AND NICOBAR ISLANDS
(CASE STUDY: 2004 TSUNAMI AND EARTHQUAKE EFFECT ON
ANDAMAN AND NICOBAR ISLANDS)
____________________________________________________
Presented by
L. K. TiwariA
Shubham GuptaA
Instructor
J.N. MalikA
A
Department of Civil Engineering
Indian Institute of Technology (IIT), Kanpur 1

2. Overview
• Causes of tsunami
• Impact on
1) Agricultural land
2) Infrastructure
3) Costal ecological resources
2

3. Tsunami (harbor wave)
Caused by processes that abruptly move large
volumes of ocean water:
• Earthquake
• submarine volcanic eruption
• coastal/submarine landslide or rock fall
• extraterrestrial impact
3

4. How do EQ cause tsunami?
4

5. 5

6. 2004 Great Andaman Sumatra tsunami
wave propagation
6

7. Impact on Agricultural Land
• sea water ingression damaged the agricultural areas and
environment which resulted in salinization of soil, which
was mainly used for agricultural purpose.
• Salted-over soil becomes sterile, and it is difficult and
costly to restore for agriculture.
• Caused the death of plants and important soil micro-
organisms. Thousands of rice, mango and banana
plantations were destroyed almost entirely and will take
years to recover.
7

8. Satellite images showing water inundated in settlement with agricultural land.
(Source: NRSA)
8

9. An Ariel view of tsunami inundation in Car Nicobar
Source: Paul, D. K. et al 2012
9

10. Impact on Infrastructure
• Most of the buildings in the islands of
Great Nicobar, Car Nicobar, and Little
Andaman were washed away by the
strong waves.
• Eastern Coast was completely
destroyed; wave height there was 10-
15 m
• There was an evidence of subsidence
and uplift in eastern and western parts
of the ANI
• Structures with circular plan
construction didn’t suffer any serious
damage
• Sea traffic was affected and
ultimately it affected the relief
operation as several jetties damaged
and collapsed
• Cause of damage to bridges was only
the negligence of the proper
earthquake zone construction
guidelines
10

11. Collapsed and submerged Jungali Ghat Jetty, Port Blair, Andaman
Island Source: Paul, D. K. et al
11

12. 12

13. Image: (a) The lighthouse tower at Indira
Point in Great Nicobar Island before the 26
December earthquake. The tower is
surrounded by lavish green grass;
residences are at the base, and a sandy
beach is in the foreground. (b) Flooding of
the lighthouse base because of land
subsidence. The submergence of 3 m was
caused by the 26 December earthquake.
(Source: Malik et al. 2006)
(a)
(b)
13

14. MES inspection bungalow on the east coast of Car
Nicobar Island, about 100 m from the shoreline
under high tide conditions.
Earthquake-shaking related collapse of a stilt-plus-
one storey house in reinforced concrete near Port
Blair in Andaman & Nicobar Islands
Collapse of a stilt plus one-storey house in
reinforced concrete near Port Blair. (Source:
Malik et al. 2006)
14

15. Impact On Coastal Ecological
Resources
Coastal Ecological Resources
•Mangroves/Forest cover
•Coral Reefs
•Sandy Beaches
15

16. Post Tsunami Coastal Information
• Total coast line 1962 Km
• 115.36 Km coastal line damaged
• Coastal landuse damaged due to Tsunami
16

17. Mangroves
17

18. Pre Tsunami Mangroves
18

19. Dried mangroves along the frontline of creeks
Post Tsunami Mangroves
19

20. Post Tsunami Mangroves
20

21. Pre and Post Tsunami Mangroves
Healthy Mangroves on 16th
Feb,
2001 (IRS-1C-LISSIII)
Dried Mangroves 11th
Feb,
2005 (IRS-1C-LISSIII)
Source: NRSA21

22. Pre and Post Tsunami forest cover changes in Little Andaman (South eastern coast)
Source: NRSA
Pre and Post Tsunami Mangroves
IRS-P6-AWiFS, dated 21-12-
2004
IRS-P6-AWiFS, dated 18-1-
2005
22

23. Pre Tsunami and Post Tsunami
Forest Cover Change in Car
Nicobar
Source: NRSA
IRS-P6-LISSIII
dated 21st December 2004
IRS-P6-LISSIII
dated 16-2-2005
23

24. Forest Cover Changes In Great
Nicobar Island
Classified map from IRS-P6 LISSIII data
24

25. Coral Reefs
25

26. Pre Tsunami Coral Reefs
26

27. Pre and Post Tsunami Coral Reefs In
Car Nicobar
27

28. North Sentinel Island Coral Reefs
(Post Tsunami)
Source: NASA, 2009
28

29. Pre And Post Tsunami Satellite Images
Of Mahatma Gandhi Marine National
Park
Source: NRSA
29

30. North Reef Island (Post Tsunami)
Source: (Kayane et. al 2007)30

31. Sandy Beaches
31

32. Pre and Post Tsunami Photos of
Carbyn’s Cove
Photo by Srikant, Research fellow at CARI, Port Blair32

33. Pre And Post Tsunami View Of Sawai
Bay At Car Nicobar
Source: (Sharma amd Bajpai, 2011)33

34. Category
Area in
2003 (ha)
Area in
2005 (ha)
Changes in
the area
(2003-2005)
Percentage
Change
Coral Reef
Coral Reef
1381.00 190.97 -1190.03 -86.17
Sand Sandy Beach
140.43 126.76 -13.67 -9.73
Mangroves
Dense
2743.05 1420.85 -1322.2 -48.20
Coastal Ecological Resources and
its changes
Source: FSI Report(2005)
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35. Conclusion
• After 18 months the salinity of the soil reduced, reaching the level
of pre-tsunami level
• Buildings in the low lying areas suffered the most.
• In some buildings and bridges the cause for damage was not just
tsunami or an earthquake, it was because of negligence of the
proper construction methodology.
• Low lying coastal area nearer to settlement, forest, forest
plantation were affected by tsunami and their total aerial extent
were decreased.
• It is observed from the tsunami that the area nearer to sandy
beaches and mangroves are highly vulnerable place and needs
vulnerability mapping.
• The damage over highly sensitive critical habitats can be easily
identified by remote sensing (RS) and GIS technology.
• Sand over reef, reef flat, dense mangrove, sparse mangrove,
degraded mangroves and sandy beaches can be identified using RS
technique.
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36. Refrences
• Datta, K. K. and De Jong, C., Adverse effect of water logging and soil salinity on
crop and land productivity in northwest region of Haryana, India. Agric. Water
Manage. 2002, 57, 223–238.
• ICMAM (INTEGRATED COASTAL AND MARINE AREA MANAGEMENT) 2005,
Preliminary Assessment of Impact of Tsunami in Selected Coastal Areas of
India. Chennai, India: Department of Ocean Development Post Tsunami field
report.
• Laxminarayana, K. and Kar A. (2010). Post-Tsunami groundwater management
studies in Neil, Havelock and Little Andaman Islands, S. Andaman District, A &
N Islands. Kolkata: Central Ground Water Board Eastern Region.
• Malik, J.N., Murty, C.V.R. and Rai C. Durgesh, Landscape Changes in the
Andaman and Nicobar Islands (India) after the December 2004 Great Sumatra
Earthquake and Indian Ocean Tsunami. Current Science 2004. [DOI:
10.1193/1.2206792]
• Malik, J. N., R. Murty C.V. & Rai D.C. (2006) Landscape changes in the
Andaman and Nicobar Island(India) after 2004 Great Sumatra Earthquake and
Indian Ocean Tsunami. Earthquake Spectra 22:S43–S66
• R. Raja*, S. Ghoshal Chaudhuri, N. Ravisankar, T. P. Swarnam, V. Jayakumar
and R. C. Srivastava, Salinity status of tsunami-affected soil and water
resources of South Andaman, India. CURRENT SCIENCE, VOL. 96, NO. 1, 10
JANUARY 2009
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37. Thanks
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