The Golden Age of lighthouse building is long since gone, so says Barry Phelan, an engineer with the Commissioner for Irish Lights (CIL). However, it is still necessary to look after the existing lights and, where necessary, replace them. One such project concerned the lighthouse at Roancarrigmore on the coast of County Cork.
It is a remote, unforgiving and beautiful place. Castletown Berehaven is the most important harbour of refuge on this coast and is regularly used by vessels in need of shelter. It is also a busy fishing port and the large deepwater bay and harbour has long been a strategic asset. Roancarrig Lighthouse marks its eastern entrance, which is accessible safely by shipping in almost all weather conditions. The previous lighthouse was classified as a “major” light which required a visibility of 18 nautical miles. On reclassification to a “minor” light, requiring only 11 nautical miles visibility the CIL decided on a new design.
A 7 metre high lightweight structure was fabricated in 316L (1.4404) stainless steel off-site at Limerick company Shortt Stainless and transported by helicopter in 3 tapering cylindrical sections for completion on-site. The external structure is made from 8 mm thick plate with a 2K “satin” finish. The choice of 316L for this marine atmospheric location is a natural one given its extensive use on offshore oil rigs. The new design allows the use of solar power and LED lights. This replaces the old diesel powered light which consumed 15000 litres of fuel per year.
The success of the project led the CIL to replace the top of another lighthouse with 316L stainless steel at Eagle Island, County Mayo.