Lucila CANDELA (1) ; Leonardo ALMAGRO (2) ; F.Javier. ELORZA (3) and Folarin. OSOTIMEHIN (4)
(1) Geotechnical Engineering Department and Geoscience- UPC. Gran Capitán s.n. 08034- Barcelona (Spain). E-mail: Lucila.candela@upc.es
(2) Aluvial-consultoría y Modelación Hidrogeológica S.L. Av. Mistral 61. 08015-Barcelona (Spain)
(3) Geotechnical-UPM. Rios Rosas 23. 080-Madrid (Spain)
(4) UNESCO. Place de Fontenoy. Paris (France)
The lake Chad basin is an inland drainage system extending over an area of about 2,355, 000 km 2 . situated in the eastern part of the Sahel region of Africa, and its active basin constitutes and important freshwater resource for the neighbouring countries. The surface area of the lake varies considerably with the amount of annual rainfall and run-off, and it is the fourth largest lake in Africa. In 1960s, the lake extension was 25,000 km 2 ; presently it has been reduced to about 2,000 km 2 . According to literature, water balance in the lake shows a close interaction between rainfall, evaporation, lateral inflow and groundwater. The Chari Logone system is the most important water supply to the lake supplying over 92% of the inflow into lake Chad. In 1997 and within the framework of UNESCO-PHI and the BMZ financial support, a project on the management of groundwater resources in the Chari-Logone catchment started with the following objectives:
The project has carried out a new wells inventory and several sampling campaigns for quantity and quality groundwater characterisation and recharge evaluation and a groundwater modelling is now on-going for water management proposal