A joint venture of Cologne-based STRABAG International GmbH and Johannesburg-headquartered multi-disciplinary construction and engineering group AVENG Grinaker-LTA has been picked by government-owned South African National Roads Agency (SANRAL) as the preferred bidders for the construction of a $123-million bridge that will be the highest in Africa when completed in 40 months.
The 50:50 JV will build the 1,130-m-long bridge over the Mtentu River near the town of Flagstaff in eastern South Africa as part of the 410-kilometer N2 Wild Coast Toll Road project that entails upgrading and widening of existing road from four lanes to six lanes between East London’s Gonubie Interchange and Durban’s Isipingo Interchange and construction of two greenfield sections of nearly 90 km.
SANRAL says in a project brief the upgraded and constructed N2 Wild Coast Toll Road sections will reduce the distance between East London and Durban by more than 85 kim, making it faster by three hours. “The road will be shorter and flatter and reduce travel time and cost, thereby reducing carbon emissions and lessen road fatalities and crashes,” says SANRAL.
The Mtentu river bridge, which has been designed by Copenhagen-based DISSING+WEITLING Architecture, will be 223 m high. It will consist of a 260 m main span constructed as a balanced cantilever sitting on 13 piers, while viaducts will be constructed using incremental launching methods.
It will be one of the two big bridges and seven slightly smaller ones to be constructed on the N2WC road. The other large span is the 580-m-long Msikaba cable-stayed road bridge, also designed DISSING+WEITLING Architecture. SANRAL is yet to award an EPC contract. The agency estimates both bridge projects would cost $250 million.
STRABAG International GmbH, a subsidiary of European construction group Strabag SE, told ENR its 50% share of the Mtentu bridge contract is approximately $63.3 million (53 million euros).
The JV Strabag/AVENG is “only to design temporary works in house” according it said in an email response. Consultancy team is led by the HVA Joint Venture of SMEC South Africa (Pty) Ltd and UK-based global consulting, design, construction and operations firm CH2M HILL.
SANRAL says the bridge project “is technically challenging and has a long span structure of international note and interest spanning a deep gorge.” Initially, the roads agency estimated the entire N2 Wild Coast Toll Road upgrading, widening and construction works would create 6,800 direct jobs and 28,000 indirect ones during the construction phase.
“The contractor will employ and train local workers in large scale as part of the local economy boost program,” said Strabag in an email response.
“The contractor will appoint suppliers and subcontractors in the next few months who have to be South African-based and registered according to contract requirements and there will be no exemptions unless the items are not available or produced in South Africa,” the company added.
SANRAL could not immediately confirm plans for issuing concessions for the road and bridges and the projected number of vehicles that will utilize the project route on a daily and annual basis.