Landslides in New Zealand kill more people than earthquakes, tsunamis and volcanoes combined and cost the country billions of dollars.
It's why scientists are releasing new guidance for councils - urging them to create their own landslide risk maps as weather events become more frequent and intense due to climate change.
Guidance co-author and GNS engineering geologist Dr Saskia de Vilder believes landslides are deadly, and costly.
"Estimates for landslide damage from Cyclone Gabrielle alone are close to $1.5 billion. This highlights the importance of considering not just the likelihood, but the consequence of landslide hazards from large storm events," de Vilder stressed.
She's been part of a team developing the guidance over the past few years, and said it contains key tools for councils to use when they're zoning land for housing development.
"The main aim of this guidance is to make sure we have a consistent approach across the country so we've got that right information to inform the right development in the right place," she added.
It's something that Nelson Mayor Nick Smith admits wasn't in place when the council allowed homes to be built on the infamous Tahunanui Slump decades ago.
"If we had the benefit of hindsight, we would not have built on the Tahunanui Slump. It is what it is though. I'm confident that with good technical expertise, we can manage those risks as best we can," Smith said.
It's decisions like that the new GNS Science advice, The Landslide Planning Guidance: Reducing Landslide Risk through Land-Use Planning, will help as it's urging all councils to develop a 'landslide susceptibility map'.
"Just trying to say where is the best place to make the smartest investments, the smartest decisions on where we build," de Vilder said.
Smith is also keen to see better development planning.
"We'll never get the situation of no risk, but this GNS guidance enables us to do is to make far better decisions," he said.
Smith knows all too well how devastating slips can be, after the Nelson Floods in 2022 destroyed dozens of homes.
One of the properties red-stickered due to a landslide, belonged to Jenny and Chris Wraight, who are now awaiting demolition of the home they've lived in for 23 years.
"It'll be harsh seeing it pulled down, but that's the harsh realities of the situation really," Chris admitted.
His wife, Jenny, told Newshub it's taken a long time to recover and move on from that traumatic time.
"It was very stressful, we found we were waking up at 2am every morning," she said.
The couple have now moved to a different property and are waiting for a council meeting in March to learn about what buy-out options are on the table.
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Their situation is one that GNS Science is hoping will be avoided in future if councils use their guidance.
Co-author and GNS senior natural hazards planner Scott Kelly said it provides the blueprint for what information local authorities need when analysing the risk of landslides.
"It's not about preventing development; it's about having the right information to inform the right development in the right place. It is hoped the recent storm events and this Guidance will be a catalyst in changing land-use planning and practice, so that the future impacts of landslides will be reduced," Kelly said.
The Landslide Planning Guidance updates previous guidance released more than 15 years ago and emphasises the need to consider climate-change scenarios that are likely to exacerbate landslide hazards due to changing weather patterns.
