Port of Ngqura in South Africa is the first port, globally, to have constructed a jet pump sand bypass system, enabling it to be in line with its dredging targets of 240,000 tons of sand per year. It’s the only port in South Africa to have a record of decision – environmental legislation – for its construction and operation.
Mainly, the port’s legislation specifies strict conditions to be adhered to in the the development of the port in an environmentally sensitive area.
Concerning the sand bypass system: It is computer-controlled and includes jet pumps which mimic the natural longshore drift of sand along the coast.
The above can be conducted by pumping the sand from the up drift (west) section of the area to the down drift (east) section of the coast.
In the meantime, the sand is captured is a sand trap and pumped through the pipelines to a discharge point on the opposite end of the port. Both capturing and discharging occur in the wave zones.
Mandilakhe Mdodana, Environmental Manager for the Port of Ngqura commented on the project
This is an achievement as we are complying with the Record of Decision (environmental legislation) which stipulated the strict conditions to be adhered to in the development of a port of this nature in an environmentally sensitive area.
Moreover, according to Bob Whitehouse, Southern Africa Shipping news, the longshore movement of sand occurs firstly on the east coast of the country where the prevailing winds and currents cause a northward movement of sand, so sand flows up the coast.
As Freddie Melikhaya, Mechanical Engineering Technician, leading the sand bypass team added
The system requires a rigid maintenance programme which keeps it going 24 hours a day, seven days a week. The port had to develop and refine maintenance-, standby- and recovery plans in time to counteract the temporary shortfall as part of a continuous improvement process. This included making provision for unplanned maintenance, daily planning and scheduling and improving maintenance techniques – all remaining within budget.
