Cape Town - The Roman Rock Lighthouse in False Bay celebrates 159 years of service this Heritage Month.
The lighthouse - the fifth-oldest in South Africa, and the only one that has been erected on a rock that is awash almost continuously at high water - was first lit on the night of September 16, 1861, the Transnet National Ports Authority (TNPA) said.
This year, TNPA commemorates 20 years of existence and its journey to maritime transformation, coinciding with Heritage Month, and highlighting the long-time service of the False Bay lighthouse.
The 14m circular cast-iron tower of the landmark is painted white with a white lantern house. The optic produces one flash every 6 seconds with a range of 20 nautical miles and is powered by a solar photovoltaic system.
The lighthouse is made of cast-iron segments bolted together, and a deep circular trench had to be cut in the rock for the foundation. It took four years to complete the installation, as only 962 hours could be spent on the rock due to the rough seas, bad weather and the fact that the rock is accessible only at low tide in calm water.
“The original optic consisted of eight single-wick burners set in silvered metallic reflectors, which provided a white flash that was visible for 12 miles (about 20km). It was rotated by a weight-driven machine, which was manually operated. Two men were on duty at a time, with a relief crew ashore,” TNPA said in a statement.
“Crews were changed every week, weather permitting, and were required to take with them oil to power the light, as well as food and water for cooking and hygiene requirements.”
Transport between the shore and the lighthouse was by means of a small row boat, and later by motor boat.
Helicopters were introduced in the 1960s and the protruding gangway was used as a platform on to which the visiting technical personnel and equipment were lowered.
The lighthouse became fully automatic on March 25, 1919, with the installation of an acetylene gas apparatus that was controlled by a sun valve. The gas accumulators were replenished every six months, and a staff presence was no longer required at the lighthouse.
“A decision was taken to electrify the light, to increase its intensity to make it more visible against the growing background illumination. A wind-driven generator was initially proposed, but was abandoned due to serious mechanical damage discovered during a trial at nearby Cape Point Lighthouse.
“The alternative was to obtain electric power from the local municipality by means of a submarine cable, with a small diesel generator to provide emergency supply if the cable was damaged. The improved light, together with a new lantern house with a glass reinforced plastic design, was commissioned on March5, 1992,” TNPA said.
The submarine cable was damaged more than once, and the protruding gangway at the lighthouse had corroded to such an extent that it became a safety hazard.
In 1994, a helipad was installed on top of a freestanding stainless steel tower on a separate protruding rock, and solar power replaced the mains supply.
The solar modules were mounted on the 13m walkway linking the lighthouse and the helipad.
“This unique lighthouse is one of 45 operational lighthouses along the coast of South Africa, from Port Nolloth on the West Coast to Sodwana Bay on the East Coast.
“TNPA, through its Lighthouse and Navigational Systems business unit, is mandated to provide, operate and maintain lighthouses and other marine aids to navigation along South Africa’s coastline,” TNPA said.