Somalia
Field Survey of the Indian Ocean Tsunami on Somalia’s Puntland Coast
Horn of Africa UNESCO Expedition March 2 to 10, 2005
Hermann M. Fritz1 and Jose C. Borrero2
1 Civil & Environmental Engineering, Georgia Institute of Technology, Savannah, GA, USA
http://www.gtsav.gatech.edu/cee/groups/tsunami/index.htm l
2 Civil & Environmental Engineering, University of Southern California, Los Angeles, CA, USA
http://www.usc.edu/dept/tsunamis/2005/index.html
Coastal regions from Southeast Asia to East Africa were severely affected by the December
26, 2004 Indian Ocean tsunami. In East Africa the tsunami impact focused on Somalia some
5000 kilometers from the epicenter of the Magnitude 9 earthquake near Sumatra. Hardest hit was a 650 kilometers stretch of the Somali coastline between Garacad (Mudung region) and Xaafuun (Bari region), which forms part of the Puntland Province near the Horn of Africa. The tsunami resulted in the death of some 300 people and extensive destruction of shelters, houses and water sources as well as fishing gear. The livelihoods of many people residing in towns and small villages along the Somali Indian Ocean coastline, particularly in the northern regions, were devastated. The immediate response by various UN agencies and other organizations has focused on meeting the humanitarian life saving needs. Limited scientific information was available on the tsunami impact on the Horn of Africa. A UNESCO expedition was organized through the Intergovernmental Oceanographic Commission (IOC) in Paris to fill the gap in terms of tsunami inundation and run-up.
At the end of February final briefings were held at the UNON headquarters in Nairobi Kenya, which is also the location of the provisional Somali government in exile. On March 2 the field survey team was dispatched on a United Nations Common Air Service (UNCAS) flight into Garoowe some 1700 kilometers north-east of Nairobi. In Garoowe the expedition was approved by authorities of the Puntland province and local team members were hired. During the time span of March 3 to 9 the team covered 1500 kilometers with off-road vehicles on the rugged terrain of Somalia between Garoove and Bossaso. On March 10 the international team members were flown out on an UNCAS-flight from Bossaso to Nairobi. The detailed itinerary and an overview of measured run-up heights are shown in Figure 1.
F ig ure 1. Measured Tsunami run-up heights alo ng the P un tl and Coa st of S o malia a nd tr ack of the e xpe di tion.
The authors surveyed the tsunami impact and wave run-up in the coastal towns of Eyl, Bandarbeyla, Foar, Xaafuun and Bargaal. The team measured the tsunami run-up heights and local flow depths based on watermarks and eyewitness accounts. The maximum run-up on these steep shores was determined relative to the sea level at tsunami impact. Each watermark was localized by means of global positioning systems (GPS) and photographed. Further inundation distances and areas of inundation were documented. In selected areas such as Xaafuun a detailed grid of various transects and shoreline surveys allowed to reconstruct the local topography and tsunami elevation in three dimensional space. The town of Xaafuun was completely flooded by up to 3m and widely destroyed due to the low elevation at the Spit connecting the Peninsula to the mainland. Nineteen dead bodies were recovered and 160 presumed missing in Xaafuun, which amounts to the highest number of casualties in a single African town. Although much higher tsunami run-up heights were measured further South along the steep shores. The highest run-up of 9 meters was recorded on a cliff near the town of Eyl. The steep coastline near Eyl and fishing boats scattered by the tsunami in the sand dunes at the bottom of the cliffs are shown in Figure 2. Rock houses severely damaged by the tsunami along the steep shore in Bandarbeyla are shown in Figure 3. The massive destruction of houses along the low lying spit of the Xaafuun peninsula is shown in Figure 4. Further numerous eyewitness interviews were recorded on video to estimate the number of waves, their height and period. The accounts generally mentioned three to four main waves with several massive waterline drawbacks in between.
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