Work begins next month to install a tsunami warning system along Christchurch's coastal area.
Christchurch Mayor Bob Parker says 22 sirens will be installed from Waimairi Beach to Sumner during May/June 2012, the system scheduled to be operational from 1 July 2012.
"It will be a comfort for Christchurch's coastal community that after many months of anxiety with ongoing earthquakes and aftershocks that there is to be a warning system in place to help protect them and their families in the event of a tsunami."
He says the warning system is just part of the solution to keep residents safe. "Residents also need to be proactive in having a self evacuation plan for their family and to know the closest safe area to them."
Mr Parker says a locally generated tsunami is likely to be a small event with a one to two metre wave, but a distant tsunami generated from a large earthquake in South America or Alaska could be as high as five metres above normal sea level when it arrives on our shores.
"With a distant earthquake we would get 12 to 15 hours notice and there are evacuation plans in place.
"There would not be sufficient time for the sirens to be activated for a local source tsunami."
He says the locations for the sirens had been chosen based on scientific advice about the vulnerability of the area; the level of evacuation difficulty; population density; and the best sound contours.
Each siren has a sound contour based on how and where it is mounted. The majority of the sirens will be placed on existing poles and structures.
"The testing of the public warning system during this time will be completed without sounding the sirens. If you hear the siren at any time, immediately evacuate your coastal environment and head for higher ground. Every step you move inland or up hill, the safer you will be,"
Mr Parker says.
"The sirens will, however, be tested audibly for the first time on Sunday 22 July at 11am for one minute. This is to enable residents to identify the sound the sirens make and to know when they will need to evacuate the coastline. Further testing of the sirens will happen each year on the Sundays when Daylight Saving begins and ends.
"Please mark these dates in your diary or on your calendar now and let your neighbours know to avoid any confusion."
He says the sirens will only be used to signal evacuation of Christchurch's coastal area in the event of a distant tsunami and possibly a regional tsunami, if time permits.
Sites for the installation of additional sirens have been identified inland from the immediate coastal area and on Banks Peninsula. Funding for these two further stages will be considered in 2013 as part of the Council's Long Term Plan 2013/22.
Mr Parker says the first 22 sirens are being installed at a cost of
$550,000 of which more than $120,000 is being funded by Eaton Industries Company. "The city is extremely grateful for Eaton's contribution to help fund the warning system."
A series of five community meetings are being held next month for residents to learn more about the tsunami risk off coastal Christchurch and the tsunami warning system.
These meetings will be held:
* South Brighton Surf Club
Marine Parade (near Bridge Street)
Wednesday 9 May at 7.30pm
* North Beach Surf Club
80 Marine Parade (near Leaver Terrace)
Thursday 10 May at 5.30pm and 7.30pm
* Redcliffs Bowling Club
9 James Street
Monday 14 May at 5.30pm
* Sumner Old School Hall
24 Wiggins Street
Monday 14 May at 7.30pm