Assessment and Planning for Tsunami Vertical Evacuation
Director's Guideline for Civil Defence Emergency Management Groups [DGL 21/18]
All of New Zealand’s coasts are at risk from tsunami. Timely evacuation, before tsunami waves arrive, is the most effective measure available to protect people from harm during land inundating tsunami.
Tsunami vertical evacuation is a last resort for life safety, risk management measure that a CDEM Group may wish to consider, when there is the likelihood that not all at-risk people are able to leave tsunami evacuation zones before tsunami waves arrive. Evacuation out of tsunami evacuation zones is always preferable, however, for some CDEM Groups, local conditions such as short arrival times and large evacuation zones that extend far in-land, can make this difficult to achieve.
This guidance covers the first phase of a two-phase process for considering tsunami vertical evacuation. This Phase One guidance includes CDEM considerations such as understanding the hazard, assessing the risk and evaluating different risk management measures.
This guidance provides CDEM Groups with a step-by-step methodology for:
- assessing their tsunami life safety risk;
- considering possible measures for improving tsunami evacuation in their areas; and
- as a last resort, evaluating whether options for tsunami vertical evacuation may need to be considered.
The phase two information has been developed by the Ministry of Business, Innovation and Employment (MBIE). This technical information is intended to inform the design, construction and operation of vertical evacuation structures.