A new report shows climate change could have a 'catastrophic' impact on the Wellington region's infrastructure, buildings and natural environment by the end of this century.
The Wellington regional climate change impact assessment report has been worked on by consultancy firm Beca, GNS Science and NIWA over the past two years.
It was recently published and discussed at Tuesday's Wellington Regional Leadership Committee.
The study conducted risk assessments across five areas - the natural environment, infrastructure, the economy, governance and social impacts on people.
It looked at the these areas across a moderate emissions scenario (global warming reaching between 1.7 and 3.2 degrees Celsius above pre-industrial levels by 2100) and a high emissions scenario (global reaching between 3.2 and 5.4 degrees Celsius above pre-industrial levels by 2100).
It found in either situation the risk to buildings in the region due to coastal erosion, cliffs and beaches will be extreme and had an overall impact rating defined in the study as catastrophic.
The risk to roads and rail due to landslides and soil erosion was also rated as extreme in both scenarios and had the same overall rating of catastrophic.
It stated that coastal flooding will have significant effects on buildings and structures near Wellington Airport, Wellington's CBD, large portions of buildings in Lower Hutt and structures near Lake Wairarapa.
Landslides were also expected to affect 990 roads and 52 railway locations by the end of the century.
The study found slips will impact thousands of buildings in Wellington City over the same period.
The report identified similar risks associated to social cohesion, freshwater ecosystems and cultural heritage in the region.
Greater Wellington Regional Council chairperson Daran Ponter told RNZ the report was a sober reminder of what issues were coming for the region.
"It's confronting particularly at a time when we are still in rebuild mode, particularly in relation to the rail network."
Ponter said he believed most Wellingtonians were committed to living in the region so they would have to find ways to do year-to-year work on infrastructure as well as accommodating changes that were coming from climate change.
Kāpiti Mayor Janet Holborow said climate change was a difficult conversation to have in her district.
"There are implications for people's livelihoods, their households and their way of life in the future."
Holborow told RNZ Kāpiti was at risk on the coast and of inland flooding.
"We need to make sure that growth happens, and development happens in areas that are sensible."
Work will now be undertaken on a report into a regional approach to climate change adaptation.