A bit about earthquakes
Earthquakes are caused by fractures within the earth's crust (fault lines) shearing or rupturing. Fault ruptures can cause ground heave or liquefaction, where loose soils change from a solid state to the consistency of heavy liquid. The ground shaking is referred to as an earthquake.
Earthquakes happen regularly and unpredictably in parts of Otago; however few cause damage and injury.
How should I prepare for an earthquake?
As seen in Christchurch, a major earthquake will cause loss of life and widespread disruption to communication, transport links, electricity and water supplies. The best way to cope is to make preparations now.
Civil Defence staff at your local council can tell you about the risk to your community and which areas are more susceptible to the effects of ground shaking, rupture and liquefaction.
Building codes are upgraded as more is understood about how buildings perform in an earthquake. Older buildings are often retro-fitted to better withstand earthquake conditions.
BEFORE an earthquake occurs
- Strap your hot water cylinder to a solid structure. It could provide an alternative water supply in an emergency
- Non-slip mats can prevent small but heavy or low centre-of-gravity objects from sliding in an earthquake
- Use nylon cord (such as fishing line for smaller items) and straps to secure taller top-heavy items that could fall over
- Use Blu-Tack or other earthquake putties to hold down glassware and small ornaments
- Use single-nail picture hooks for light pictures and double-nail for heavier pictures or mirrors. Ensure nails are hammered into solid parts of the wall or framing studs. Push the hook closed
- Secure all units, bookcases and tall furniture to wall studs to prevent them toppling over
- Secure your chimney with galvanised metal angle iron with bands at the top, ceiling line and bottom. Bolt through the cladding to the rafters or ceiling joists
- Put heavy or sharp-edged items on low shelves or in cupboards with secure latches to reduce the risk of moving
- Check your household insurance is current
- Don't put chemical cleaner in the toilet cistern. This will poison a potential source of drinking water
DURING an earthquake
DROP, COVER, COVER HOLD
If you are inside during an earthquake:
- Take cover under a table or brace yourself in a doorway. If you're in a lift, stop at the nearest floor and get out
- DON'T try to run outside
- DON'T look for your pets until shaking stops
If you are outside during an earthquake:
- Take cover in a doorway
- If you are driving pull over to the side of the road and stop. Stay in the vehicle as it will provide some cover
- If you are by the sea move to higher ground (at least 15 metres above sea level or at least 1 km inland) immediately if you notice the sea receding and bubbling or can hear it roaring
AFTER an earthquake
Long or Strong, GET GONE
If you are in a coastal area and you feel a earthquake that lasts longer than a minute, don't wait for a tsunami warning. Move immediatly to higher ground or as far inland as you can. Walk if you can. Stay there until you get the all clear.
- DON'T run onto the street
- Check those around you and help them if necessary
- Put out small fires. Evacuate the building if they can't be controlled
- Turn on your radio
- Locate and secure your pets
- Make sure someone reports the damage in your neighbourhood to the local civil defence contact
- DON'T go sightseeing