Landslide Assessment & Prevention of Future Risks
Monts BAMBOUTOS, CAMEROON
September 2003 / May 2004


THE DISASTER

Photography by 0juku Tiafack

In June and July 2003, a series of important landslides happened in the Monts Bamboutos (western Cameroon) and in their surroundings, causing a large number of casualities and leaving many people homeless.
In particular, the landslide at Maghah caused 20 deaths, the one in Batibo 3 deaths, the one in Bafou 2 deaths, and the most important, at Wabane caused one death and very important material damage. 309 houses have been destroyed.

These landslides are associated to the very heavy precipitations of the rain season in 2003 (rain season from end of May to end of October).
They are becoming now a recurrent threat in these areas which are located in very strong relief of volcanic origine.

In front of what is now considered a permanent high risk, and in the expectable perspective of generalized landslides and of a major disaster in these densely populated mountains, the local and national authorities remain powerless with regard to the decisions to be taken.
In any case, accurate regional mapping was considered an urgent necessity, to determine the risk areas, and to define the sectors where the population could eventually be moved into safety.

Location of the study area in Cameroon Mean climatic conditions (rainfall & temperature in the lowlands)


THE OPERATIONS


Status of operations :
  • Request received from the "Centre de Recherche des Hautes Terres", University of Dschang, and from the Cameroon Environmental Watch (CEW), on September 21, 2003.
    Other users are: the Cameroonese Red-Cross, the "Institut National de Cartographie", the communes, the prefectures, etc.
  • Action engaged under mandate of the Canadian Space Agency on October 20, 2003.
  • Collection of satellite imagery: ERS-1 SAR (2 frames), LANDSAT-4 TM (1 frame), LANDSAT-5 TM (1 frame), LANDSAT-7 ETM+ (2 frames), and LANDSAT-7 PAN (2 frames), September/December 2003.
  • A RADARSAT-1 SAR Image (SGC, standart beam S7) has been acquired by RADARSAT International on November 11, 2003, and has been made available to the project by the Canadian Space Agency.
  • Field trip to the Bamboutos mountains in Cameroon, with documentation of the landslides, and collection of GPS mesurements. Local contact and meetings with the end-users. (December 2003 - January 2004)
  • A first database containing satellite imagery from 1988 to 2003 as well as topographic maps built using satellite radar (SAR) imagery has been delivered to the end-users at the end of February 2004.
    This database forms the base of a regional Geographic Information System (GIS), in order to spatialize all the related information collected.
    This delivery has been done timely, before the rain season of 2004, which is when a new series of landslides occurred.
  • End of Canadian Space Agency / ParBleu project on February 28, 2004.
  • In May 2004, the integration and analysis of a TERRA-ASTER image acquired on March 08, 2004 contributed to the identification of landslides risks for the next rain season, in the summer 2004.
  • Results: no more casualities in the monitored area in 2004, 2005 and 2006.


  • The project will follow-on soon, since the threat is still present:
        - Collection of additional satellite imagery
        - Collection of ancillary information
        - Integration into a regional Geographic Information System (GIS)

Photography by Appolinaire Zogning

The area that has been surveyed extends over 70 x 50 kilometers (latitude 515' to 550' N / longitude 950' to 1015' E).
All satellite maps shown in these pages are produced in cartographic projection UTM WGS 1984 (Zone 32 N),
and at a spatial resolution of 30x30 meters and/or 15x15 meters.


MAIN THREAT: THE BAMBOUTOS CALDERA

  • Understanding the causes of the landslides, using satellite imagery
        The potential of satellite imagery for the prevention of landslide damages
     (1988-2003)

  • The potential main landslides, identified from satellite imagery  (2002-2003)

  • A radar view of the great Bamboutos caldera  (RADARSAT-1, November 2003)

  • OTHER THREATENED AREAS IDENTIFIED

  • The town of Bamenka  (1988-2002)

  • The town of Djuttitsa  (1988-2002)

  • TOPOGRAPHY OF THE MONTS BAMBOUTOS

  • Topographic maps of the Mounts Bamboutos

  • Stereoscopic view of the Bamboutos caldera

  • THREATS FOR THE 2004 RAIN SEASON

  • New views from space  (TERRA-ASTER, March 2004)

  • Related Pages at the NASA Earth Observatory (June 02, 2004) :

  • EO Newsroom: New Images - Landslides in Cameroon
  • EO Natural Hazards - Landslides in Cameroon

  • Produced by PARBLEU TECHNOLOGIES Inc. under mandate of the CANADIAN SPACE AGENCY
    (Standing Offer for Disaster Management Information Products and Services; PWGSC File Number 9F028-014927/A)

    Operational partners of PARBLEU TECHNOLOGIES Inc. :
    Privateers NVTreemailAP Formation

    Copyright (C) PARBLEU Technologies Inc., 2003/2004