The Pacific Islands are home to some of the most beautiful scenery in the world, with stunning turquoise water and lush landscapes attracting millions of tourists each year. Superficially, these crystal-clear waters and the islands they surround may look healthy and thriving, but, beneath the surface – like most countries – some Pacific Island nations are facing a range of water challenges.

UNSW’s Water Research Laboratory (WRL) has been working with partners in the region to help manage these issues, with the two latest projects focusing on coastal protection for Pacific Island countries and water quality and lagoon health in Rarotonga, Cook Islands.

In partnership with the Pacific Region Infrastructure Facility (PRIF) and NZ consultants Tonkin + Taylor, WRL recently contributed to the development of technical guidelines to assist governments, coastal managers, consultants, non-government organisations and contractors to understand the issues around coastal erosion in the region, where the impacts of rising sea levels and human activity are being felt.

The publication, titled Guidance for coastal protection works in Pacific island countries, provides an overview on how to identify a coastal erosion issue, how to determine the most appropriate mitigation solution, and how to assess design conditions. It also outlines the steps required to ensure robust engineering design of protection works, assess environmental effects, obtain the necessary construction documentation, and monitor effectively throughout the process.

WRL undertook physical modelling of a range of innovative coastal protection options that maximise the use of local materials and labour, while minimising the need for imported materials and equipment. The results from the physical modelling helped to develop design guidance for these novel coastal protection applications.

Meanwhile, in the Cook Islands, WRL is assisting the Government with a series of environmental investigations and work focussed on Muri Lagoon in Rarotonga - a tourism hot-spot which has suffered from a range of water quality issues over recent years.

Under the umbrella of the Mei Te Vai Ki Te Vai project, the WRL team is working with the Cook Islands Ministry of Marine Resources (MMR), GHD and Southern Cross University to undertake investigations on water quality and lagoon health. Excess nutrients, catchment and land-use management, as well as potential changes to lagoon flushing, are all impacting the health of the lagoon—and WRL has been engaged to undertake coastal processes modelling and lead a comprehensive coastal and oceanographic data collection program.

Principal Coastal Engineer Matt Blacka and UAV Pilot Chris Drummond are travelling to Rarotonga in the coming weeks to begin the project. Once in full swing, the investigation will see Muri Lagoon become one of the most instrumented coastal areas in the Pacific region. This data will be used to provide guidance on long-term improvements to catchment and lagoon health, ensuring that ecosystems, local communities and the tourism industry continue to co-exist sustainably.

To learn more about the UNSW Water Resources Laboratory, visit the website