Calculated risk

Imagine if you could foresee what would happen to your home in a severe flood or tsunami, and then work out how to prevent or reduce the impact before any such event occurred.

Imagine if you could foresee what would happen to your home in a severe flood or tsunami, and then work out how to prevent or reduce the impact before any such event occurred.

That’s what NIWA and GNS Science’s joint RiskScape tool does for suburbs and whole cities.

The power of the RiskScape tool in supporting risk-based decision-making explains why NIWA is leading a three-year project to tailor RiskScape to weather and geological hazards threatening urban areas and infrastructure in Samoa and Vanuatu.

RiskScape is already used in New Zealand to forecast economic and human impacts of disaster events, such as earthquakes, flooding and tsunamis. It identifies how to reduce risks through developing plans, strengthening infrastructure, building barriers, or buying insurance.

Kate Crowley, leading a RiskScape project in Vanuatu and Samoa.

The tool converts asset and hazard information into likely impacts on a locality or region—calculating, for example, likely building damage and replacement costs, human casualties, economic losses, business disruption, and the numbers of people injured and displaced.

NIWA project leader Dr Kate Crowley says the Samoa and Vanuatu project is no ordinary tailoring task.

“We will use the process of tailoring RiskScape to understand their specific country issues and needs, and teach people how to use and adapt it themselves in the future.”

An early phase of the training has been visits to New Zealand by disaster management officers from Vanuatu and Samoa, in which they have been introduced to RiskScape.

Crowley says this will be the first time that RiskScape has been used for drought and tropical cyclone impact forecasting. It could lead the way towards rapid and targeted emergency response in the Pacific and in New Zealand.

“There is a significant lack of hazard-informed planning, which time and again leads to loss of homes, livelihoods and, in the worst-case, lives.

“It is exciting work, because timely information about potential hazard impacts can save lives.”

Six of the best

Helping Pacific partners fine-tune RiskScape for their own purposes is not the only challenge of the three-year programme. RiskScape will be tailored by applying it to real-life risk reduction.

Western Samoa after the 2009 tsunami.

Crowley visited Vanuatu and Samoa in September last year to hold two-day workshops to identify which hazards the government felt best suited to the tailoring exercise, and which risk-reduction issues they really wanted to crack. A wide range of stakeholders were invited to each workshop—from national planners and infrastructure providers to emergency services. They considered the purpose of impact modelling, the demands of scenarios covering multiple events at the same time, the types of assets most valuable and most at risk, and how information would be best delivered.

“The result of the conversations is that we will tailor the tool by applying it to six of the toughest risk-reduction issues,” Crowley says.

Samoa chose to tailor RiskScape by applying it to tsunami risk and loss modelling for response planning; near real-time impact forecasting for tropical cyclones; and landslide risk round Mt Vaea for development planning.

Vanuatu’s case studies were looking at the impact of volcanic ash on Tanna Island, tropical cyclone impact, and impact forecasting for agricultural production from drought and extreme rainfall.

The case studies will be co-developed and implemented over the next two years of the project.

PARTneR is being funded through the New Zealand Partnerships Fund administered by the Ministry of Foreign Affairs and Trade, and is managed by NIWA in collaboration with five partners: the Samoa Disaster Management Office; the Vanuatu Disaster Management Office working with the Vanuatu Meteorology and GeoHazards Department; GNS Science and the Pacific Community – Geoscience Division.

[This feature appeared in Water & Atmosphere 18]

Preparing for the worst

By Sally Laven

Titimanu Alain Simi was a young boy when two deadly cyclones hit Samoa in quick succession.

Tropical Cyclone Ofa struck in 1990, killing seven people on the islands. Eighteen months later, Tropical Cyclone Val hit, leaving 16 people dead across Polynesia, crops ruined and eighty per cent of Samoa’s homes damaged. The tall, quietly spoken Samoan remembers the rush to get to a secure shelter after his house, its roof leaking, flooded in the night.

“I remember my dad and my uncle having to take us kids, carrying us to the church in the rain and wind. They tried nailing down the roof, but it was hopeless.”

Some years later, at university in Fiji finishing his Bachelor of Environmental Studies, Titi recalled his shock at seeing the images of the devastation left by the tsunami which swept onto Samoa in 2009.

“The scale of the disaster really affected me,” said Titi, who was relieved his immediate family lived inland and were unhurt. It was something new that we hadn’t experienced before.”

Titi returned to Samoa the following year and was affected by the stories he had heard about the utter devastation many had experienced. This included his relatives, whose beach resort on the south coast was completely flattened by the disaster and a tourist killed.

Now as a Disaster Management Officer with Samoa’s Ministry of Natural Resources and Environment, Titi is helping to prepare his country for future cyclones and other natural hazards. He spent several weeks at NIWA in Wellington learning how RiskScape works and how it would be used in Samoa to help forecast the impact of cyclones and tsunamis, and reduce the risk of landslides on Mt Vaea, the mountain overlooking the Samoan capital, Apia.

Dave Allen
Titimanu Alain Simi.

Titi said RiskScape came at a pertinent time for the Disaster Management Office, which had been working to ensure all government bodies included risk planning in their policies.

“I think this tool will help enhance that and also strengthen collaboration between ministries.”

Titi is looking forward to utilising RiskScape during the formulation of development plans for the slopes of Mt Vaea. If a major landslide occurred on the mountain, not only those living there would be affected. Businesses, infrastructure and people in Apia might also be hit. Titi said data collection and consultations had already begun among the growing number of settlements on Mt Vaea.

“A lot of the families requested better drainage, better roads. So, with the information this tool can produce, it will certainly support putting these things in place and can also help inform regulations and policies. For example, if someone wanted a permit to build a new house, consideration would be given to the risks illustrated by the tool.”

Titi said one of the main challenges over the next couple of years would be just getting everyone on board back home. 

“Getting data from relevant partners can be quite a challenge, so I guess the challenge for me will be to convince people they should.”

But he did not anticipate it would be too difficult.

“They say a picture is worth a thousand words. For example, we can have a map and highlight areas where landslides can occur and show them this is what will happen. I’m still learning about the tool. The more I learn, the more ammunition I’ll have to convince people to take this on board.”

Graham Smart, NIWA
NIWA is helping Samoa plan to avert the disasters caused by cyclones and tsunami.

The collaboration with NIWA also involves training local staff how to use RiskScape.

“One of the good things about the project, one of its core components, is to train the local people back home to use the tool,” said Titi. 

“We will firstly need to know what kind of data is needed and why, and as we move on to the next stage of the project we will learn how to use the tool. The challenge for me is to sell the tool, but once people understand what it’s for and what it can do for us, I’m confident they’ll be on board and see its importance,” said Titi.

“It’s a powerful tool and it will certainly mean better informed decision making.”

[This feature appeared in Water & Atmosphere 18]

Related information