Vetiver in the Cook Islands: Researching Alternative Solutions to Wastewater Management, Erosion Control, and Slope Retaining for Rarotonga.
A Kirkwood, J Flanagan, 2019.
Compiled by Andy Kirkwood and Justine Flanagan.
Contact: [firstName] @ islandbooth.com.
Published 23 May 2019. Updated 15 November 2019.
From 2017— Rarotonga, Cook Islands is the site of a number of large-scale transformative infrastructure projects, including water supply, roading, drainage, and wastewater management. How we approach these projects will have a long-term impact on the health of our community — and the health of our island. Vetiver grass is central to a number of low-cost, sustainable alternative bio-engineering solutions.
The variety of vetiver grass used for bio-engineering is also known as Sunshine (United States), Khus Khus (India), Monto Grass (Australia), Moras (Phillipines), and Muskus (South Africa). 
Vetiver grass (Chrysopogon zizanioides L.) is a fast-growing, deep-rooted plant that has been used internationally as a low-cost, environmentally-friendly alternative to traditional ‘hard’ engineering solutions. The grass is the foundation of the Vetiver System (VS), researched and sustainable method of addressing agricultural, infrastructure, and environmental management challenges.
Vetiver was introduced to the Cook Islands to the island of Atiu as a source of perfume for massage oil , then propogated in response to siltification of the central fresh water source. . It has also been used as erosion control in the makatea (fosilised coral) islands of Mangaia, Atiu, Mauke and Mitiaro .
In the capital island of Rarotonga:
As an alternative to concrete-and-steel or block retaining, the use of vetiver has significant environment benefit, beach sand is not required, the retaining gets stronger as it ages, and the root systems also manages site drainage.
The way that vetiver grows make it suitable for a range of uses.
Barriers to the uptake of the Vetiver System may be its origin, and how information about the plant has been disseminated.
Vetiver grass is native to India. From the mid-1980s the World Bank encouraged research into uses of the plant; to enable developing tropical and semi-tropical nations to address agriculture and infrastructure challenges — mainly in asia.
Research and implementation of the Vetiver System was furthered by non-government organisation The Vetiver Network (now The Vetiver Network International). Vetiver Network publications such as Vetiver Grass – A Hedge Against Erosion (PDF) are practical guides written for fieldworkers and farmers .
Although the plant and its application has been extensively researched, it is often lesser-known by civil engineers from temperate, first world countries.
At the same time, urbanisation and changes in government policy have resulted in a loss of community-knowledge. In Fiji, vetiver-hedges were introduced in 1956 to retain soil and as moisture control . In the 70s and 80s the Fiji government priority shifted from land conservation and the use of vetiver; to the farming of sloping land for export. Local knowledge and use of vetiver declined.
In his project providing low-cost sanitation solutions for Haiti, Roger Giezten has observed:
Another unexpected problem that I have encountered, is that some Haitians reject the [vetiver] latrine.
So far I have found that the people with no toilet or latrine at all, universally embrace it.
The ones who reject this have been men in leadership positions, who have nicer toilets at their homes, and feel the vetiver latrine demeaning to the people they serve. They have made this decision without actually asking the people themselves. It appears that it is pride which causes them to reject this solution even when no other solutions are in sight.
The Vetiver Latrine. Roger Giezten, May 2019. Accessed 17 Aug 2019.
Climate change impacts due to shifting sea-levels and changing weather patterns — along with the scale of such impacts — now make necessary investigation of low-cost sustainable biological solutions such as the Vetiver System.
Classification/subjects: vetiver grass, Chrysopogon zizanioides, coastal protection, coastal erosion, Rarotonga, Cook Islands, South Pacific islands, climate change, flooding, Mei Te Vai Ki Te Vai, waste water treatment, effluent, septic systems, reverse technology transfer, biofiltration, phytoremediation, vetiver system.
Infrastructure Cook Islands has formed separate teams to manage large-scale infrastructure projects.
Vetiver plant biology, application and planting methods.
Updated: 15 November 2019.