The construction of the second carriageway of the Bakwena N1N4 Toll route by JG Afrika (Pty) Ltd, a 100-year-old leading multi-disciplinary consulting engineering company, and a Joint Venture (JV) between Raubex and Enza Construction was completed in October 2021. The upgrade has improved the user experience and provides a safe connection between the platinum belt in the North-West and the economic hub of Gauteng, while also ensuring the efficient movement of goods and people between South Africa and Botswana.
JG Afrika has been involved in the project since 2016 when the firm was appointed to undertake the preliminary design of the second carriageway of the N4 between Ga-Rankuwa in Pretoria and Brits in the North-West. The project then progressed to detailed design and procurement with the Raubex/Enzo JV being awarded the R500 million construction contract. JG Afrika were also entrusted with supervising the construction works which commenced in March 2018.
The project included the construction of 28 km of the new eastbound carriageway of the N4 Toll Road. To accommodate the second carriageway five road bridges were widened, two new bridges were constructed including one over the Crocodile River Bridge and seven major culverts where extended.
The project was an extensive undertaking that also involved a large quantity of earthworks. Most of the road is constructed on the expansive clays, which needed to be removed prior to construction of the road and replaced with rock fill. If the clay is left in situ it would have resulted in premature failure of the road. In total 724 000 m3 of rock fill was brought onto site to replace the clay material. The rock fill material was sourced from a local mine, which meant that the material did not have to be sourced from a borrow pit. This helped to lessen the environmental impact of the project. The clay material was then spoiled in a variety of ways such as using the clay to flatten the batters and increase the safety of the road.
Emma Day, a JG Afrika Executive Associate and Highway Engineer, says that the upgrade of the N1N4 is one of the firm’s many flagship road construction projects.
“We achieved exactly what we set out to do which was to deliver infrastructure of the highest possible quality to Bakwena Platinum Toll Concessionaire. This can also be attributed to excellent dynamics and clear communication channels between the engineering team, the client and the principal contracting JV, which also brought extensive skills and experience in road construction to the project,” Day says.
A highlight of the large construction project was the significant positive socio-economic impact that it had on the communities adjacent to the road in the City of Tshwane Metropolitan Municipality and Madibeng Municipality. This was achieved through extensive use of local labour and businesses.
Notably, the contractor exceeded its socio-economic and development targets on this contract. By the end of the project over 30% of the construction value had been allocated to work completed by local targeted enterprises with over 56 qualifying small enterprises (QSE) or exempt micro enterprises (EME) companies being utilized. A further 10% of the construction value utilized on local labour spend.
Environmental and occupational health and safety compliance formed an important part of the project with the contractor being audited on a regular basis. The Raubex /Enza JV consistently scored highly on their OH&S audits and when the COVID-19 pandemic hit, measures were put in place immediately to protect the health of all staff and allow for the continuation of the works.
The project overcame many challenges ranging from technical to social. This was achieved in no small part by the excellent team dynamic between the Engineer, the Contractor and the Client. When a problem arose, all parties came together to find a workable solution.
Day says that she is proud of JG Afrika’s ongoing involvement with Bakwena Platinum Concessionaire. “We were again also s
upported in the field by the client’s very knowledgeable engineers. They are passionate about delivering road infrastructure that will significantly improve safety and experience for road users”.
The construction of the second carriageway N4 between Ga-Rankuwa and Brits forms part of the larger upgrade to the N4, which by the end of the concession period, will result in a dual carriageway highway from Rustenburg to Pretoria. The construction of the second carriageway of the N4 will dramatically improve the safety of this route and will result in improved economic connectivity between the regions.