Small Dams in the Zambezi Basin

Contracting entity:
ARA-Zambeze

Project description

Strategic Plan for the Development of Water Storage Small Dams in the Zambezi Basin

The general objective of this Plan was to identify the potential (technical, social and economic) for the development of works for the storage of water, with particular emphasis on small-scale works, in the various districts of the Zambezi basin, with special attention being paid to areas of greater water deficit (Tete Province), in which the water element may constitute a condition for the development of the region.

In total, some 280 and 940 small water storage dams are expected to be built to meet at least part of current and future needs (rural support) respectively. The annual volume guaranteed with the construction of these small projects amounts to about 62 Mm3 (30% of the total demands considered) in the current situation and about 168 Mm3 in the future situation (15% of the total demands considered). For the priority sub-basins, it is expected that 98 small projects will be implemented in the current situation and 271 in the future situation. It should be noted that in most of these sub-basins the demand for irrigation, and sometimes for rural support, is high, particularly for the future situation, so that the satisfaction of the demands will naturally involve the construction of other types of uses, so that there is economic sustainability. In view of the analysis of priorities, it was proposed to allocate the investments in the different phases according to the following criteria

• Short-term: investment in priority sub-basins to meet current needs (according to 2015 indicators) – MZN 4.1 billion.
• Medium term: investment in the remaining sub-basins to meet current needs and investment in 50% of the number of dams identified as necessary to meet the needs in 2045 in the priority sub-basins (according to the 2045 indicators) – MZN 11.1 billion.
• Long-term: investment in all the infrastructure needed to meet the needs of the year 2045 in all the sub-basins – MZN 27,1 billion.

In terms of maintenance and operating costs, it is estimated that an annual charge equivalent to around 0.3% of its investment value is required to guarantee the operation and operating conditions of the infrastructures, which results, in a first phase, in annual values of around 12 million MZN, which will rise proportionally to around 126 million MZN in the long term.

Name of Associate Consultant: ENGIDRO – Estudos de Engenharia, Lda.