The Maguga Dam Project (original) (raw)

Komati Basin Water Authority (KOBWA)

The Maguga Dam

The Maguga Dam on the Komati River some 12 km south of Piggs Peak will be 115 m high when it is completed in September 2001. There are three larger structures in the region being the Katse Dam in Lesotho, and the Kariba and Cabora Bassa Dams on the Zambezi.

The Komati River drains an international drainage basin which is the source of water for South Africa, Swaziland and Mozambique.

The Komati Basin Water Authority (KOBWA) has been established as a bi-national agency under the terms of the Komati Basin Treaty between South Africa and Swaziland for the purposes of implementing Phase 1 of the development of the Komati River Basin. Phase 1 consists of two sub-phases, namely Driekoppies on the Lomati River in South Africa (Phase 1a) and Maguga Dam on the Komati River in Swaziland (Phase 1b).

The project to construct the Maguga Dam was awarded to the Komati Dam Joint Venture (KDJV - a joint venture between Group Five Swaziland, WBHO Swaziland, LTA, Grinaker and a Swazi consortium) for a contract amount of E343 489 654 and a contract period of 34 months.

The Joint Water Commission monitors the activities of KOBWA on behalf of the government s of Swaziland and South Africa.

In terms of the treaty entered into by the two countries, the cost of the project and the distribution of the water from the dam will be shared 60% 40% between South Africa and Swaziland respectively.

Earthworks for the construction of the dam will include more than 2 million m� of excavations, 1.45 million m� of drill and blast rockfill, 813 000 m� of clay core material for the dam wall, 2.8 million m� of rockfill for the dam wall and 457 000 m� of crushed filters for the dam wall. Major concrete quantities include 132 000 m� concrete, 8 000 tons or reinforcement and 78 000 square metre of formwork. The vast majority of the earthwork materials will be excavated from areas behind the dam within the inundation zone of the reservoir so will be submerged and 'out of sight' when the reservoir fills.

Other notables of the Dam include:

• a dry core rockfill dam 750m long and 115m high
• a river diversion by means of two tunnels about 410m long and an upstream cofferdam 15m high
• a concrete intake works consisting of a 102m high dry tower and a 12m diameter shaft over the outlet tunnel
• a bifurcation of the outlet tunnel consisting of the penstock tunnel to the power station and a river outlet works
• a raw water pump station including pumping main from outlet works to a water treatment plant
• a clay core saddle dam approximately 300m long and 15m high
• a labyrinth type concrete spillway, chute and deflector bucket including a 9m wide concrete road bridge carried along the top of the spillway and comprising 9x25m spans
• civil and structural construction of a power station

Engineering, water utilisation and economic studies have indicated that the optimum development is a 115 metre high dam impounding a reservoir having a full supply level of 626 m.a.s.l. and a gross volume of 332 hm3. The optimum size for the hydro-electric generating plant at the dam has been shown to be 15 MW installed capacity.

Further Details

Further details of the project can be obtained from:

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The information provided above does NOT in any way represent the OFFICIAL opinion or views of KOBWA or the Swaziland Government about the Maguga Dam Project

This page was last updated on 05 November 2001