CDR International in association with Shore Monitoring and Research defined an integral full survey campaign for the lower basin of the Msimbazi River, which was executed last February. This World Bank funded survey project serves two purposes: 1) generation of reliable, accurate and fit for purpose bathymetric & topographic data of the Msimbazi River and its floodplanes for riverine flooding related detailed studies, and 2) rigorous comparison of Digital Terrain Model (DTM) generation by Unmanned Aerial Vehicle (UAV; drones) Photogrammetry and UAV LiDAR. Traditionally LiDAR aerial acquisition methods for obtaining DTMs are done by planes. With the development of equipment, the LiDAR scanners are getting smaller and lighter, and drones can fly longer and can carry more weight, enabling to mount LiDAR scanner to drones. This potentially provides significant cost savings compared to both traditional LiDAR and field surveying methods. A meticulous comparison for the Sub-Saharan African context was however lacking. This study will recommend on when to use which surveying methods with respect to purpose, project area size, landuse/vegetation cover and challenges like import of equipment.
Preliminary insights of the analysis have been shared and presented recently at a master class at the Land and Poverty Conference 2019 – March 25-29, 2019 Washington, DC and at a workshop on DTM drone applications for Dar es Salaam stakeholders at World Bank Office in Dar es Salaam on April 11th, 2019.
