Indian Ocean Wave Tsunami Exercise 2018

The 11th Session of the Intergovernmental Coordination Group for the Indian Ocean Tsunami Warning and Mitigation System (18 to 20 April 2017 in Putrajaya, Malaysia), established a Task Team to organise the next Indian Ocean-wide tsunami exercise (IOWave18) in the second half of 2018 and encouraged maximum participation from all Member States, where possible, to community level. Exercise IOWave18 contains two earthquake scenarios on successive days, 4 and 5 September, with both scenarios run in real-time.

Exercise Scenario

The purpose of Exercise IOWave18 was to evaluate and improve the effectiveness of the IOTWMS, through its operational TSPs, NTWCs, NDMOs and LDMOs, in responding to a potentially destructive tsunami.

The exercise will comprise two scenarios on successive days that will generate simulated tsunami waves travelling across the whole Indian Ocean basin. The first scenario simulates a magnitude 9.0 earthquake in the Makran Trench off the coast of Iran and will commence at 0600 hours UTC on 4th September 2018. This simulated tsunami will take approximately 11 hours to travel from its source to the Western coast of Australia. The second scenario simulates a magnitude 9.3 earthquake in the Sunda Trench West of Northern Sumatra, Indonesia, and will commence at 0300 hours UTC on 5th September 2018. This simulated tsunami will take approximately 8 hours to travel from its source to the coasts of Iran and Pakistan, and 11 hours to travel to the Southern coast of South Africa.

Image Map

The Maximum Wave Amplitude of 9.3 earthquake scenario in the Sunda Trench West of Northern Sumatra
The Maximum Wave Amplitude of 9.0 earthquake scenario in the Makran Trench off the coast of Iran


Member States are invited to participate in either or both events, which will run in real time. The scenario start times was chosen to be more convenient for the “near field” (i.e. local) countries for each scenario. Participating countries followed the exercise timelines precisely or elected to exercise on their own timeline in order to achieve their particular objectives.

The TSPs (India, Indonesia and Australia) will issue an initial Exercise Announcement Message to start the exercise on each day. Thereafter, NTWCs will receive Notification Messages from the TSPs according to the timelines, which will direct NTWCs to the TSP password-protected websites to view the detailed exercise bulletins and detailed threat information. Countries are encouraged to conduct the exercise in real time and use the TSP websites to access the bulletins and other threat information available there.

To facilitate the conduct of tabletop exercises and for planning the evacuation exercises, the full set of exercise bulletins are separately provided in Supplement 1 (Scenario 1 – Makran Trench) and Supplement 2 (Scenario 2 – Sunda Trench),

More information of the IOWave18 exercise could be found at website:


Following the exercise, participating countries are requested to complete the online Exercise Evaluation Survey. This feedback will assist in the evaluation of Exercise IOWave18 and in the development of subsequent exercises. The evaluation is integrated into the IOWave18 Report that was made available after the ICG/IOTWMS meeting in March 2019.

Download the Report