Progress has been made on both underground and above ground facilities at the Ingula pumped storage scheme in South Africa despite delays following a fatal incident at the site in October last year, consultant Royal HaskoningDHV has announced.
Now in its seventh year of construction, the project was originally expected to have one of its four 333MW reversible pumped turbines under commissioning at this time. However, the site was closed by the Department of Labour in October after a tragic accident led to the death of six construction workers.
Since then, undergound work has proceeded with the concrete lining in the tailrace and headrace tunnels completed. Cavity and consolidation tunnel grouting are about 75% complete and concrete slip forming at one of two 91m high Surge Chambers recently commenced. All civil works in the transformer hall have been completed and the machine hall and underground control room are nearing completion, Construction Senior Supervisor Jacques du Plessis from consultants Royal HaskoningDHV, one of the three firms of consultants that make up the design and construction supervision team, Braamhoek Consultants Joint Venture, explained.
“The first turbine shaft and runner were taken underground recently, two generator transformers have been installed and mechanical and electrical fit-out work is underway," he said, "Above ground the operations and maintenance building on the intake structure is nearing completion as is the stop log storage facility at the outlet."
The double-storey Administration Building, whose basement has direct access to the main tunnel leading to the underground power station, has also recently been completed. In addition to office space, the building accommodates the external control centre for the power station. Also recently completed is the Visitors Centre, which comprises a small office wing, a cinema, various display halls, an auditorium and facilities wings. The surrounding area will be landscaped with indigenous plants to minimize the visual impact of the surface buildings.
“Amidst all this heavy engineering work, Eskom is conscious of its environmental responsibilities and in particular the site's bird life" added du Plessis. More than 275 bird species have been sighted at Ingula including all three crane species that although rare, are regularly seen there. "The endangered Southern Bald Ibis is another resident of the conservation area and thirty breeding pairs have been counted. However, construction of the upper Bedford Dam, completed in 2011, robbed them of their historic nesting ledges, causing Eskom to construct a massive artificial nesting site to compensate for the loss of their originals," he explained.
The dam is expected to fill to capacity during 2015 for the first time and the hope is that before then the birds will discover the new nesting site themselves. Several dummies were placed in the new site to entice them to relocate. The change in habitat due to the construction of the dams is being monitored by conservation staff and already new species are moving into the area such as spoonbill and flamingo.
Anticipated completion and operation of the first of the four pump / turbines is expected by May 2015 with the remaining units coming on stream over the following 12 months.
Braamhoek Consultants Joint Venture (BCJV) comprises local consultants GIBB, Royal HaskoningDHV and Knight Piésold. It is responsible for the overall design and construction supervision of many of the packages within the greater project.
The Eskom owned project is located between Ladysmith and Harrismith in the Little Drakensberg, and will have a generating capacity of 1332MW available during periods of peak demand and to supplement base load when necessary.
