With the ongoing implementation of the environmental strategy of Transnet National Ports Authority (TNPA), the Port of Richards Bay is taking the lead as the first port in South Africa with the largest floating breakwater system (pontoons) constructed within its harbour.
Pontoons are erosion-control structures that usually run parallel to the shore to protect the area from the full force of incoming waves. The system is designed to achieve 70% to 80% wave reduction efficiency.
Tau Morwe, Chief Executive of TNPA said: “This initiative forms part of TNPA’s mandate to enhance South Africa's global competitiveness by facilitating the expansion of the economy through socially and environmentally sustainable port development.
“This strategy also complies with health, safety and environmental legislation and regulations as well as international protocols and codes ratified by SA.”
During the construction phase of the Bulk Liquid Berth in 2009, a comprehensive Environmental Impact Assessment revealed that an endangered area had developed on the south side of the Richards Bay harbour. Erosion of beach sand and soil had affected the natural habitat of the Mangrove swamps.
These swamps form the basis of a complex marine food ecology and their coverage of coastal shorelines and wetlands provides a unique habitat for many diverse species of birds, mammals, crustaceans and fish.
Following this assessment, mitigation measures were identified to preserve the area. These studies considered all the variables and impact of the proposed structures on the shoreline.
“We looked at three key environmental performance criteria and found that the floating breakwater systems (pontoons) allow sufficient tidal exchange between the mangrove and open port waters; it allows faunal migration between mangroves and open tidal waters; and the helix anchors on the seabed will also allow for the establishment of an artificial habitant which invertebrates, fish and birds will likely colonise.
“Hence the implementation of the pontoons was the preferred option, as it met with the specified requirements,” said Brahma Naidoo, project leaderfrom Transnet Capital Projects.
Construction and installation of the pontoons between the beach along the Heritage Site and the Bulk Liquid Berth 208 at Spinach Point in the Port of Richards Bay has now been completed.
“There will be constant monitoring of the area and we feel confident that in the long term, these pontoons will rehabilitate the mangrove ecology by reversing the damage caused by the waves, inevitably enabling the restoration of the natural habitat for plant and animal life,” said Morwe.