Tsunami Advisory 002 - Bay of Plenty potential marine and beach threat

Wednesday, 6 February 2013 5:45 p.m.

Bay of Plenty Civil Defence Emergency Management Group advises coastal water users to be on alert for strong currents in harbours and tidal surges near river mouths following this afternoon's magnitude 8.0 earthquake in the Santa Cruz Islands.

The Ministry of Civil Defence & Emergency Management (MCDEM) has issued a national advisory - tsunami potential marine and beach threat for Gisborne, Bay of Plenty, Auckland, North Cape, Waikato, Taranaki, Manawatu/Wanganui, Kapiti, Marlborough, Nelson/Tasman, West Coast, Milford, Dunedin and Chatham Islands.

The Bay of Plenty Civil Defence Emergency Management group is continuing to monitor the situation.

People in the above coastal areas should:

1. Stay out of the water (sea, rivers and estuaries, including boating activities)
2. Stay off beaches and shore areas
3. Do not go sightseeing
4. Share this information with family, neighbours and friends
5. Listen to the radio and/or TV for updates
6. Follow instructions of local civil defence authorities

Historical comparisons suggest that the amplitudes are likely to be greatest in the central west coast of New Zealand, between Hokitika and New Plymouth; and also in the far north of the North Island (Ahuriri Peninsula). Elsewhere it is anticipated that the threat lies towards the lower end of the Marine Threat (0.2-1.0 m amplitude) band.

MCDEM says historical experience and modelling experience suggest that the largest waves will be several hours (~2-8 hours) after the first arrivals.  The first arrivals are likely to be small.

In many locations the primary concern is likely to come from strong currents within harbours and surges in river mouths.

The tsunami potential threat will remain in effect until a cancellation message is issued by MCDEM.

Only messages issued by MCDEM represent the official warning status for New Zealand, not those issued by the Pacific Tsunami Warning Centre (PTWC).