A new computer model has been developed to help Tonga prepare for the effect a tsunami would have on the capital, Nuku'alofa.
The model, developed by the Secretariat for the Pacific Community, shows that an 8.7 earthquake in the Tonga Trench would create a wave that would inundate the city.
The graphics show only four areas in Nuku'alofa would be spared by such a wave and people will only have between seven and 20 minutes to reach those points.
The Director of the Tonga National Emergency Management Office, Leveni Aho, says the models give the government a clearer picture of how to prepare for a major earthquake and tsunami.
"We're currently working with our other partners on developing public awareness, leading them to higher ground, trying to find evacuation centres and evacuation routes to these areas, and also an early warning system because I think the biggest issue here is we don't have much time."
Leveni Aho says the model is of a worst case scenario so the capital can be as best prepared as possible.