Realization of a small dam in Central Tanzania: an example of direct cooperation between CGT and local users

Country: Tanzania

Starting Date: 2007 - Completion Date: 2009

Project: NUFFIC, Center for Environmental Planning and Technology Rwanda

Project Supervisor: Pier Lorenzo Fantozzi

Subjects: Environmental sciences, Informed governance, Water resources

Project Summary

The project's goal is the construction of a small dam in the Municipality of Kongwa (Dodoma Region, central Tanzania), in order to mitigate the rain irregularity which frequently causes the lost of crops, during the seeding and germination phases. The project has been proposed by the italian missionaries which live in this area since the Sixties. After a preliminary draft of the dam project, the CGT members have supported several mission in order to improve the topographic database of the area and to survey meteorological and geological data through GPS techniques and Laser Total Station. During this mission many students and teachers working within the CGT staff, have collected samples of rocks and soils which afterwards were analyzed by the CGT's Geotechnics laboratory, in order to define the properties of soil and rocks of the dam site.

There were elaborated many maps of the interested area and the project were presented in march 2008. After this stage other improvements about the knowledge of the hydrology of the area has been performed and a final version of the dam was constructed in the 2009. The dam will be realized using a set of Maccaferri gabions filled by boulders, with a central septum of impervious layer realized in geotextiles. The dam will catch 418,000 cubic meters and has been meeting the needs of more than 2,000 families of local croppers.