02 October 2014 - The National Directorate of Water (DNA) through the Regional Administration of Water South (ARA-Sul) has awarded a contract for the rehabilitation of the damaged bottom outlets and related works on the 48 metre high Massingir Dam in the Gaza Province of Mozambique.
Aurecon has been appointed to supervise the construction of these rehabilitation works.
Following the raising of the full supply level of the dam by the installation of six large spillway crest gates, a sudden failure of the outlet conduits in May 2008 resulted in an uncontrolled discharge of approximately 1 000 cubic metres per second to the downstream area, threatening the safety of the dam.
Aurecon was previously appointed to investigate the cause of failure of the bottom outlet works, design the rehabilitation of the bottom outlet works, compile tender documentation and provide technical services for the client.
“Our local engineers, who have experience working with ARA-Sul and who are familiar with the local environment, will be supervising the construction and they will be supported by specialists in South Africa,” Peter said.
The rehabilitation works comprise the installation of 6.4 metre diameter steel liners into the existing reinforced concrete outlet conduits, installation of hydro-power offtakes, mass and heavily reinforced infill concreting and grouting, and rehabilitation of the two downstream radial control gates, including entirely new hydraulic and electrical equipment.
Other work on the dam includes the construction of large diameter pressure relief wells, installation of supplementary dam safety instrumentation and crest lighting on the 4.5 kilometre long earth fill embankment.