SPOT 5 maps flooded roads in Namibia

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Namibia has declared a state of emergency in response to the flooding caused by heavy rains in the north of the country. A map of flooded roads around the town of Oshakati was produced from a SPOT 5 satellite image to help organize relief efforts.


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Event
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Heavy rains since the start of the year have brought widespread flooding to southern Africa. On 19 March, Namibia declared a state of emergency in five regions in the north of the country and sent out a call for international aid.

 
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Need
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Flood-hit regions are experiencing a cholera epidemic and the authorities fear this water-borne disease could spread further. A map of flooded roads was therefore needed very quickly to allow relief teams to reach and treat the population. 

 
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Solution
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At the request of the member agencies of the International Charter on Space and Major Disasters, Spot Image tasked the SPOT 5 satellite to acquire an image on 24 March. 


 
 
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Results
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A map of flooded roads around the town of Oshakati was produced using several remote-sensing techniques. Main roads were digitized and flooded areas extracted by classification from band 3 of the SPOT 5 satellite. These two layers of information were then combined in a GIS to highlight flooded sections of road.

 
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At full resolution, flooded road sections in green show that the towns of Oshakati and Ongwediwa are completely cut off.

 
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Benefits

The SPOT 5 scene used to map flooded roads proved an effective crisis management tool. It helped to organize relief team access to flood-hit areas, decide which vehicles were needed to reach them, locate alternative dry-land routes and identify suitable sites for medical and humanitarian camps.

 
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