As Wellington and north Canterbury get back to their feet after the magnitude 7.8 earthquake in the early hours of Monday morning, people will be counting their blessings in the capital city that it seems to have escaped lightly. Elected officials will be keen to portray their areas as open for business, not affected by the earthquake and welcoming visitors.
All this is well and good. If buildings can be quickly made safe to reopen then they should be. However the shadow of Christchurch, where buildings that were damaged in aftershocks between 04 September 2010 and 22 February 2011, were allowed to reopen looms large. It does so for very good reasons and they should not be ignored.
Haste will not help. Hastily fixing things increases the risk of their failure in the future. Hastily reopening helps to ensure at some – possibly totally inopportune moment – your business/home will be off limits again because due diligence was not done. The Christchurch/Canterbury earthquake sequence lasted the better part of six months before the 22 February 2011 aftershock – there is nothing to say that the north Canterbury quake aftershock sequence will not behave like this (and in some respects it already is). It is totally realistic to expect another aftershock with a magnitude at or close to magnitude 7.0.
For building owners the most important lesson has been that if you spot damage or have good reason to believe there is earthquake damage in a building you live or work in, GET IT CHECKED (the building in the photo (taken 04 September 2010) was demolished within 48 hours of 22 February 2011)after a wall fell off). The dodgy parapet on the corner of a building or that brick facade from the 1880’s that has a crack in it needs to be fixed. Those cracks will grow with aftershocks. If steel in concrete structures is exposed, it will begin to oxidise and lose its bearing strength. I took photographs between September 2010 of such buildings. Some of them failed severely on 22 February 2011.
Don’t be afraid to close buildings as a matter of precaution. Disruptive as it might be to the tenants and the building owner, there is no comparison with what may happen were an unsafe part of the building to collapse on people outside it. If you are a landlord to rental properties, get latches installed on cupboards to minimise contents damage. Consider tying back large items such as flat screen televisions, free standing shelve units so that they do not start bouncing about or ‘walking” during large aftershocks.
Document quake damage so that when it comes time to laying a claim with EQC and/or your insurance company you can say with certainty what happened. Get a second opinion if you are not sure about something your insurer or EQC are telling you
Good luck Wellington. Listen to Christchurch. These lessons were not taught just to be forgotten and retaught in the most dreadful some day in the future. Heed them. Now.