Northland Tsunami Evacuation Zones (Open Data)

With the dozens and dozens of coastal communities along the 3200km plus coastline that makes up the Northland Region it is important is be aware of the tsunami zones in preparation for a tsunami event. The Northland Tsunami Evacuation Zones have been prepared by the Institute of Geological and Nuclear Sciences Limited (GNS Science) for Northland Regional Council and can be divided into two categories (zones): Orange and Yellow.  The Green Zone is symbolization of the land area not highlighted by the Orange and Yellow zones.The Red Zone: This zone represents the area that is has been identified as the highest risk and should be considered off-limits during and after a tsunami event. This zone usually covers the shoreline, a marine and beach areas which also include rivers, estuaries and harbours. This zone should be evacuated for any tsunami warning that has a minimum warning threshold (currently set) between 20cm amplitude up to 1m amplitude. For purposes of mapping, NRC utilise Mean High Water Springs (as supplied by LINZ) as the Red Zone.The Orange Evacuation Zone:  This zone represents a middle zone, created to avoid over-evacuation and the associated issues that this can create when there are official warnings that can extend pass the Red Zone – meaning that the tsunami is more than an hour away in travel time therefore there is time for an official warning and are expected to have a maximum amplitude of 3-5metres. In the case of larger tsunami, evacuation may escalate to clearing the Yellow Zone.  

The Yellow Evacuation Zone: This zone represents the area that should be evacuated for precautionary reasons in the case of highest predicted magnitude tsunami.  These events are often indicated by natural/informal warning signs (long, strong earthquakes) or where there is a maximum amplitude that equated to the 2500-year return period wave amplitude at the 84% level of confidence.  This zone should cover all maximum creditable tsunami events including the highest impact events.

The Green Evacuation Zone: This zone represents a safe area that should not be physically impacted by a tsunami. People evacuating the Red, Orange and Yellow Zones should retreat to this area. 

Data and Resources

Additional Info

Field Value
Theme ["geospatial"]
Maintainer NRC_admin
Created 2018-11-06T22:33:56.000Z
Date modified 2020-06-17T23:56:32.000Z
Language English
Spatial {"type": "Polygon", "coordinates": [[[172.6259, -36.4009], [174.7507, -36.4009], [174.7507, -34.3809], [172.6259, -34.3809], [172.6259, -36.4009]]]}
Source Identifier
Record created August 16, 2020, Last Updated August 16, 2020