Lights out for South African lighthousePublished 3/7, 2018 at 12:56
The possibility of an important, but potentially dangerous, unmanned lighthouse toppling into the Indian Ocean off the east coast of South Africa, has been removed following a delicate demolition operation.
The problem was highlighted in a previous issue of PDi, where the Richards Bay lighthouse has been imperilled by bank erosion by the action of the ocean over nearly four decades. This prompted an international navigational warning by the South African Maritime Authority (SAMA) to maritime movement using what is known as the ‘Cape sea route’.
Durban based Atomic Demolishers was tasked with the job of demolishing and removing the lighthouse by South Africa’s National Ports Authority (NPA). Originally the lighthouse stood more than 200m from the cliff edge, but erosion has seen its location now being literally metres from the edge, which has significantly reduced the options for removal. Demolition was thus chosen following deconstruction, and a temporary rebuild being considered, and then rejected, with demolition being considered the safest option.
A NPA spokesperson said, ‘The accepted proposal involved anchoring the structure to two purpose built concrete anchors and pre tensioned cables to secure and control the direction of the structure’s collapse. The demolition took place under the guidance of a structural engineer. Once the pre tensioning was completed, the base of the tower was chipped and broken away using a hydraulic excavator mounted breaker and the concrete rubble disposed of.’
A temporary light and structure, commissioned on 1 April after testing and calibration, now guides vessels navigating the Richard Bay and surrounding waters. Construction of a permanent replacement will commence later this year.