This Sunday, 22 September at 18.30pm, Fiji TV?s ?Close Up? will screen ?Lifuka Island ? The Coastline of a Future Pacific?, a documentary that explores this small community?s struggle to adapt to a rapidly changing coastline. Lifuka?s story also provides important lessons for all small, vulnerable coastal communities throughout the Pacific region that are concerned about the impacts of sea level rise.
Lifuka is the administrative centre of Tonga?s Ha?apai Group and, in May 2006, a magnitude 7.9 earthquake caused the western coastline of the island to subside by 23cm. Since the earthquake this small community of 3000 people has witnessed significant erosion impacting on houses and key infrastructure located along three kilometres of its foreshore area.
Because of this unique event Lifuka was chosen as part of a regional effort to understand how vulnerable Pacific Island communities can adapt to the impacts of rising sea levels. Arthur Webb, Manager of the Oceans & Islands Programme at the Secretariat of the Pacific Community says the rapid subsidence in Lifuka resulted in the equivalent of rapid sea level rise that could provide an opportunity to understand what projected sea level rise may mean for other vulnerable coastal communities throughout the region.
?We were interested in what the dynamics of shoreline erosion and coastal vulnerability were in association with that rapid sea level rise. And that might be a way for us to get a better understanding of what the future might be in terms of processes under current regimes of sea level rise across the region,? he says.
With support from Australia?s ?Pacific Adaptation Strategy Assistance Program? the Tongan Government worked with the Tonga Community Development Trust and experts from the Secretariat of the Pacific Community to help the Lifuka community understand the problem and the most cost-effective solutions. The project took a unique approach by combining scientific surveys of the coastline and groundwater resources together with community surveys and discussions about their coastal problems and the potential solutions
It is expected that, over the next several decades, rising sea-levels and resulting wave impact particularly at high tide will rapidly deteriorate the existing coastline and inundate the infrastructure situated along the Lifuka?s western shoreline. Jens Kruger, an Oceanographer from the Secretariat of the Pacific Community, says that much of the community has already been impacted by coastal inundation that has forced some families to move inland.
?At the moment probably 30% of the population that lives within 120 metres of the shoreline, have already experienced flooding and a large proportion of those households are experiencing flooding on an annual basis. I think with climate change, or further subsidence, there are going to be more people that will need assistance,? he says.
However, Mr Kruger says that aerial photography dating back to 1968 has shown that the earthquake was not the only factor that has contributed to the significant coastal erosion witnessed in Lifuka.
?It looks like parts of the coastline at least have experienced up to 40 metres of erosion in the last four decades and it turns out coastal erosion was actually a problem even before the earthquake and the subsidence. There seems to have been a lot of development on the coast as well, that has interrupted the sediment supply in the past, so the beaches were not as healthy and able to naturally adjust to any natural changes that were occurring,? he says.
The documentary examines the struggle of this remote rural community, with limited available land, to find practical solutions that will enable its families to adapt to the changing coastline of a future Pacific. The three main adaptation options include: planned migration inland; sand replenishment and; the construction of an engineered revetment or seawall.
While it is clear that no form of seawall can halt the impacts of rising sea levels, the story of Lifuka poses challenging questions for all Pacific communities that are being forced to deal with the increasing risks posed by their own vulnerable coastlines.