SLIDESHOW: View images of the New Zealand earthquake destruction

Hurricane Katrina in 2005 is the world’s costliest insurance loss at more than $71 billion. If the losses from this New Zealand earthquake reach $12 billion, it would rank eighth, in front of 2005’s Hurricane Rita at about $11.1 billion and behind 2005’s Hurricane Wilma at about $13.8 billion, according to data compiled by the Insurance Information Institute.

Christchurch, New Zealand’s second-largest city, was struck by a magnitude 7.0 earthquake in early September 2010. The more recent temblor is actually considered part of the aftershock sequence from the September quake, said AIR, adding that many affected structures may have been weakened by the first earthquake.

Modeler Risk Management Solutions (RMS) said the shaking from the Feb. 21 earthquake is considered “severe” on an intensity scale, meaning there is the potential for moderate to heavy damage to resistant structures and heavy damage to vulnerable structures.

“Reports confirm that damage is considerable in Christchurch’s central business district and is more extensive than following the September 2010 earthquake,” said Emily Paterson, associate manager of catastrophe response at RMS. “The most severe damage reports stem from the town Lyttelton, closest to the earthquake’s epicenter, though reports are still emerging given the restricted access to the area.”

While there are strict guidelines for newer buildings, the central business district is home to many historical buildings of masonry construction and few have gone through a seismic retrofit, said AIR. The modeler said the city’s infrastructure has also been significantly damaged.

Reports say 75 people have died from the earthquake, although that total may rise since hundreds are missing or trapped. RMS said two buses were crushed by collapsed buildings, contributing to the high death toll.

Modeler EQECAT, while stating that damage from the quake was sure to eclipse $1 billion, said the damage was difficult to gauge because the most fragile buildings were already damaged in September and only partial repairs were started.