FACE OF DISASTER
Wellingtonians could flee the region at a rate of 10,000 people per day following a large earthquake on the Wellington Fault, with transport and vital infrastructure taking months or even years to repair.
The Wellington Lifelines Regional Resilience Project has laid bare the devastation facing the region should vital infrastructure not be built or upgraded before a magnitude 7.5 quake hits.
And even with a 20-year, $5.3 billion investment programme, the region would still face major disruptions to its economy, tourism and everyday functions.
The Wellington Lifelines Group based its modelling on a magnitude 7.5 earthquake because it represented a major event that still allowed for a credible recovery.
It was also the magnitude used for insurance and business continuity planning, the group said.
There was a 10 per cent chance of a 7.5-magnitude earthquake occurring within the Wellington region in the next 100 years.
It would be two weeks before emergency vehicles could operate between Wellington Airport and the central city, including the Cook Strait ferry terminals, if a quake were to strike today.
Hutt Valley would be the worst-affected regional area – cut off from central Wellington and the airport for three months.
It would take 104 days for full service to be restored between Wellington Airport and the central city, and up to six months for transport links to be fully restored between central Wellington and the Hutt Valley.
If the recommended changes were made, it would still be two weeks before emergency vehicles could operate between the airport and central Wellington, but as little as 15 days before they could operate between the airport and the Hutt Valley.
Wellington’s rail network would be closed to freight for between one and three years, and cut off to passengers for three to 31⁄2 years, according to the report.
Interislander freight would be out of action for two to three years.
If the full suite of infrastructure investments were made, freight would be out of action for between six months and 21⁄2 years; passenger services would be cut for just under three years; and Interislander freight would be restored within one to 21⁄2 years.
With no intervention, CentrePort’s ferry terminal would not be functional for one to three years, and would not return to full service for up to three years.
The main Thorndon terminal would be functional in one to three months, but
would not return to full service for at least three years.
With investment, the ferry terminal would be functional in four weeks and would return to full service in two years.
The Thorndon terminal would also be functional in four weeks, but would still not return to full service for at least three years.
Electricity and water
As it stands, the majority of the lower North Island would be without electricity for up to six months, with the rest out for up to one month.
If the upgrades were made, most of the lower North Island would be cut off for up to three months, with the rest out for up to a month.
Telecommunications services would be severed for up to a month across most of the region; this would reduce to up to a week if the changes were made.
Water outages would continue for up to six months in most of the region if the status quo was retained. But with the recommended changes, they would last for up to three months in the lower part of the region, one month in the central part of the region, and six months in the upper part of the region.
Tourism and business
With the ferry and road disruptions, Wellington could expect domestic tourism to be down by 92 per cent and international visitors to be down 96 per cent for the first three months.
Those time frames would reduce to about one month following the necessary upgrades.
And following the big one, people could start leaving the region at a rate of 10,000 per day after the first two weeks.
However, it was expected that between 40 per cent and 85 per cent of people would return to the region within a year, if services were restored.
‘‘Evidence from the Christchurch earthquakes and other disasters indicates that people are far more likely to relocate close to home, and to then return if and when conditions improve,’’ the report said.
Estimates show that if up to 30 per cent of commercial properties across the region were unusable following the quake, 10 per cent of businesses would leave the region.
Exploratory drilling to find an alternative route to run a drinking water pipe and keep the capital afloat in a disaster is nearing its end. Designs for the resilient water source, earmarked to cost $116 million, can get under way in the new year if the investigative stage of the cross-harbour pipeline project is finished by Christmas. The jack-up barge, steadfast on the seabed in Wellington Harbour, has been spotted in points between Lowry and Evans bays throughout the year. The equipment, a secondment from Auckland’s waterfront preparations for the America’s Cup, drills every day to collect cores that are studied and tracked for the suitability for the project. So far, everything looked good, Griffiths Drilling managing director Mel Griffiths (pictured right) said. The pipeline was one of two options considered to ensure the capital continued to have a freshwater supply should it be hit by a natural disaster. The other involved sourcing water using bores from the Waiwhetu Aquifer, near Matiu/Somes Island. But the option was abandoned due to the poor quantity and quality of water found. Wellington Water community engagement manager Alex van Paassen said it was an expensive project but one Wellington could not do without.
There is a 10 per cent chance of a 7.5-magnitude quake occurring on the Wellington Fault in the next 100 years.