Bi-national infrastructure and water transfer: Experiences from Southern Africa

摘要

This paper focuses on a bi-national water augmentation project within the borders of South Africa and Lesotho in Southern Africa, in accordance with a treaty signed in 1986. The world-class infrastructure project diverts water from the Senqu/Orange River system in Lesotho to South Africa's water-stressed economic driving force, the Gauteng region. Completed in 2001, the project was the first in which the state-owned Trans-Caledon Tunnel Authority (TCTA) was responsible for the development of infrastructure, In addition to being tasked with funding the water transfer part of the project, the TCTA is now responsible for overall debt management. Tunneling constituted a major component of the project: It entailed, inter alia, the building of three dams - the Katse, Mohale and Muela dams - an intake tower, a hydropower station, two transfer tunnels and a delivery tunnel. The Katse dam was a particular showpiece, being a double curvature concrete arch, 185m high and 710m along the crest. The design was the most cost-effective to span the wide U-shaped valley of the Malibamatso River, downstream of its confluence with the Bokong River. It also allowed water to be impounded at low risk while construction was taking place. Most significantly, an idea that was born in the deeply-incised valleys of Lesotho has now connected Lesotho and South Africa, not only as a symbol of their interdependence, but also of their joint efforts to secure a more prosperous dispensation for both countries.