Cape Town – Cape Town’s Green Green Point Lighthouse has turned 200 years old and it will be open to the public for a limited period.
Captain Sabelo Mdlalose, Transnet National Ports Authority's (TNPA's) executive manager: Lighthouse and Navigational Systems, said curious minds who always wondered what the red and white lighthouse on the promenade looked like inside could finally have a look.
The public will be given this opportunity today, free of charge, between 10am and 3pm.
They are encouraging young and old to discover and learn about the history of the lighthouse.
Views from the lighthouse can include Urban Park, Signal Hill, Robben Island and the mist that rolls into Table Bay.
A landmark on the promenade in Mouille Point, it was commissioned on April 12, 1824.
The original tower had two separate fixed white lights.
“These lights were single-wick Argand lamps that burned sperm whale oil,” said Mdlalose.
Mirrors reflected the light from the lamps, resulting in feeble rays that were visible for less than 10 kilometres.
In 1864, the tower was increased to its present height of 16 metres to accommodate the new lantern house, and a revolving lens was installed.
This lantern house is still in use today.
The present 3rd Order catadioptric rotating lens system was installed in 1922, and the light was electrified on March 31, 1929.
The present 400-watt metal halide lamp produces one flash every 10 seconds.
Mdlalose said the lighthouse is connected to the mains supply and has a standby diesel generator.
Maintenance is carried out by TNPA teams.
“Originally, a submarine bell was used at Green Point to warn ships of fog,” he said.
This was replaced by a diaphone fog signal on January 1, 1926, which used compressed air to vibrate the metal diaphragms resulting in a low frequency “grunting” sound. The present nautophone fog signal was commissioned in November 1986.
“This type of fog signal uses electric current to vibrate the metal diaphragms, which produces a higher frequency sound.”
According to Mdlalose, the Green Point Lighthouse is the oldest of South Africa's 44 operational lighthouses.
TNPA is mandated by the National Ports Act, 2005 (Act No 12 of 2005) to provide, operate and maintain lighthouses and other marine Aids to Navigation (AtoNs) to assist with the navigation of vessels within commercial port limits and along the coast.
A marine AtoN is defined as: “A device, system or service external to vessels designed and operated to enhance safe and efficient navigation of individual vessels and/or vessel traffic.”
Lighthouses, beacons, and buoys are the most common types of visual AtoNs.
“Virtual AtoNs are new technology that use digital signals to warn of dangers in specific locations, without the need for physical buoys or lighthouses.
“The digital signals are transmitted from Automatic Identification System (AIS) stations and are received by AIS units on board vessels.
“Large vessels such as container ships and passenger ships are required to carry AIS in terms of International Maritime Organisation regulations, but smaller vessels are not.
“Visual marine AtoNs cannot be done away with.
“TNPA AtoNs conform to the standards set by the International Association of Marine Aids to Navigation and Lighthouse Authorities (Iala). South Africa, represented by TNPA, is a founding member of Iala.”
