Abstract EN:

Situated to the confluence of Chari rivers and Logone, built on an clayey substratum and flat, N'djamena the city of Chad knows to each season of rains, owed floods to the believed ones of Chari, to its different tributaries that the crossing, but also to the waters of his own impluvium. To these natural floods add the numerous sand careers extraction and of disseminated brickworks in all the outskirts of the city in which ones the stagnations of waters themselves perpetuate. At last, the insufficiency of drainage networks, the omnipresence of the rubbish that plug these networks do only amplified the stagnations. Although the state initiated several drainage projects and of improving of sanitation with the help of the international cooperation, the problem of floods remains constant. This position already preoccupying will have for consequences, the installation to each season of rains, of cholera epidemics, of typhoid fever, of malaria. . . In the omnipresent pool, deposit themselves faeces matters induced by the runoff. Thus, all these constraints gush out on the management of the city that becomes each more and more difficult day, inducing with her, the degradation of the life framework. In this thesis, we wanted to bring knowledge on the management of the improving sanitation method of the city; next by many cartographical analyses and statistical, by investigations, grasp the relations that exist between the constraints of the site and his organization, note the resultant failure of this last one and propose solutions in order to reduce the consequences of the improving sanitation lack