Dam Synchronisation and Flood Releases - agriwaterpedia.info

DAM SYNCHRONISATION AND FLOOD RELEASES IN THE ZAMBEZI RIVER BASIN: ANNEX 4 OF FINAL REPORT
4 New Multipurpose Dams on the Tributaries
4.1 Introduction to the investments
New dams on unregulated tributaries which contribute to flood flows could be regulated with
multi-purpose dams and thereby help to improve flood control. These dams are not necessarily
designed for flood control only, but may serve other purposes like hydropower production or
irrigation. In this Chapter both dam sites that have been identified before as well as dam sites
that are identified in this study are evaluated.
4.2 Situation assessment: stakeholders views
As mentioned in the previous chapter, SADC recognizes the essential need for and benefits of
dams and their inevitable role to the development in Southern Africa. Taking into account the
existence of other alternatives, the development of dams will need to be considered from a
holistic perspective, within the framework of Integrated Water Resources Management (SADC,
2006). In this chapter it is important to add that SADC had explicit reservations to the World
Commission on Dams and Development report: ―There is a perceived danger that if dams are
not accepted where appropriately needed, the regional peoples could be confined to under
development, resulting in perpetual poverty. In practice, compromise will be inevitable if
development is to continue.‖ ―Efforts on the use of small dams for multi-purposes would be
encouraged since these would contribute significantly to ensuring reliable domestic and livestock
water supply in rural areas, support small scale irrigation, promote tourism, and regulate seasonal
flows to provide reliable all-year round flows.‖ (SADC, 2006)
This situation assessment focuses mainly on stakeholders‘ opinions regarding the feasibility of
development of new dams for flood regulation and flow regulation in general.
The unregulated tributaries identified at Inception stage are the Kalomo and Luangwa Rivers in
Zambia, the Gwayi and Sanyati Rivers in Zimbabwe and the Luia River in Mozambique. The
opinion of the three countries in which these tributaries are situated is important. The Kalomo
tributary was not mentioned during the interviews in Zambia. In Mozambique the Revubué and
Luenha were added as important tributaries that cause flooding. The Shire tributary in Malawi is
dealt with under ―Regulation of Shire River and Lake Malawi‖, Task 6.
Zambia (Luangwa)
The Department of Water Affairs (interview 14 June 2010) pointed out that priorities of the
Zambian government have been education and health care. The priorities of the Department of
Water Affairs dictate that making water available for irrigation and water supply supersedes new
infrastructure for flood protection. The Department does not know of any dams planned in
Zambia that could contribute to flood management. Some small dams on tributaries of the
Luangwa could be used for irrigation, but, by virtue of their small sizes, they would hardly
contribute to flood protection.
The Department noted that dams proposed for flood protection should also have other benefits
if they are to be considered. Indications of flood prone areas within Zambia are mainly on
tributaries to the Zambezi. The Barotse floodplains experience flooding, but would not be
considered as a flooding problem that requires addressing. Traditional systems that sound drums
as a means of flood warning are in place and are not in need of urgent improvement. The
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