Tiempo Climate Newswatch

An Adaptation Strategy in the Cook Islands

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	Imogen Ingram describes an innovative design for coastal defence as an adaptive measure to climate change for Small Island Developing States.
The author is Te Pa Mataiapo, a traditional leader, in Raratonga involved in both climate change and development issues.

The Cook Islands is an archipelago of fifteen islands spread over more than 1,000 kilometres from the Tropic of Capricorn in the Southwest Pacific. Similar to its nearest neighbours, French Polynesia, Niue, Fiji and Samoa, the Cook Islands' most severely-felt impacts of climate change are caused through inundation by sea surge and flooding from heavy rain during severe weather events.

Flooding of low-lying areas and invasion by very high seas have lead to coastal erosion and consequent loss of land. Cyclone Martin, which struck Manihiki Atoll in the Cook Islands during 1997, caused waves to inundate the atoll, and resulted in the loss of nineteen lives and of 95 per cent of all buildings. Most of the remaining residents were evacuated to Rarotonga, the main island, for up to twelve months while some residents went overseas and have never returned. Future impacts will include longer dry periods resulting in water shortages and threats to food security.

The advice we have received suggests two approaches for affected Small Island Developing States to adapt to climate change - bearing in mind the cross-cutting issues of methodologies, data capture and modelling, and integration into sustainable development.

First, we need to improve our ability to cope with or respond to the impacts of climate change through gathering of information, researching, making plans, forming networks and discussion fora. For island residents, this translates as assessing vulnerability and impacts, and we hope for rapid vulnerability assessment methodologies in view of the prevailing threat to many island nations.

Second, we need to implement adaptation activities through laws or policies, organizational change or individual action. For island residents, this means adaptation measures and planning. With this in mind, we advocate the implementation of actual projects such as pilot demonstrations and case studies so that we can 'learn by doing' instead of awaiting the result of the stock-taking process.

John Hay of the International Global Change Institute, at the University of Waikato, New Zealand, carried out an intriguing cost-benefit analysis in 1994 of some of the practical adaptation projects that the Cook Islands might implement.

His analysis showed that deepening the streams around the island of Rarotonga by 900mm would significantly reduce flooding from heavy rain and improve drainage. The costing for a project like this was considerably less than some of the other options, for example, increasing the size of bridge culverts, and benefited many more residents. This could be one example of 'learning by doing' that could be implemented promptly.

James Carley, a senior project engineer at the University of New South Wales Water Research Laboratory in Australia, used computer simulations to assess what the impact of Cyclone Meena on Rarotonga during February 2005 would have been had the cyclone hit the island directly. The results of the simulations showed that giant waves would have crashed through the business district of the island.

During October 2005, James Carley researched the usefulness of an innovative concrete coastal protection device (COPED), which had been designed by Don Dorrell of Rarotonga. There are several trial COPEDs installed around Rarotonga, and Don Dorrell is confident that they reduce the energy of storm waves.

Patented internationally in 1993, these COPEDs may well become the crucial factor in coastal defence if widely adopted at vulnerable spots. There are three main designs. One tall version has been installed to protect Rarotonga airport, where reclaimed land projects into the lagoon. A second version was successfully trialed that resulted in significant sand accretion, as well as dissipation of the energy of waves. The third design that Don Dorrell has recently worked on is a hinged version that is raised in the event of a storm.

The photos accompanying this article show the breakwater COPED protecting Raratonga International Airport. The COPEDs use approximately one quarter of the concrete required for alternative breakwaters and the crest levels can be significantly lower.

There has been a lot of interest in the COPED units, both locally and internationally. The results of further modelling and testing at the University of New South Wales Water Research Laboratory in Australia are keenly awaited by residents. If the devices prove to be effective in the laboratory, then their construction and installation would constitute a very important pilot project.

Establishing COPEDs at vulnerable points of coast would constitute a significant adaptation measure which would greatly improve the resilience of Small Island Developing States to major impacts of climate change.

Further information
Imogen Ingram, Te Pa Mataiapo, PO Box 492, Raratonga, Cook Islands. Fax: +682-22128. Email: imogen@oyster.net.ck.

On the Web
The Tiempo Climate Cyberlibrary presents a listing of theme sites on Small Island Developing States.

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