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.

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.
 
 

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. 
 

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. 


 
 

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.

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

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.