IOWave25 exercise: 15 October 2025

MAURITIUS METEOROLOGICAL SERVICES

IOWave25 exercise on 15 October 2025

Background

Tsunamis do not happen often, but when they do, they can affect entire coastlines, and sometimes even cross whole oceans. The devastating earthquake and tsunami of 26 December 2004 in Indonesia showed the tragic consequences of not having an effective tsunami warning system. The event caused severe damage and casualties across much of the Indian Ocean, reaching as far as South Africa.

 

Following this disaster, the UNESCO Intergovernmental Oceanographic Commission (IOC) set up the Intergovernmental Coordination Group for the Indian Ocean Tsunami Warning and Mitigation System (ICG/IOTWMS). This group coordinates a network of National Tsunami Warning Centres (NTWCs) across the Indian Ocean.

 

Today, this system operates as a coordinated network. Each NTWC in member countries issues tsunami warnings to its population, based on information provided by three Tsunami Service Providers (TSPs) namely Australia, India and Indonesia. The effectiveness of this regional warning system has been tested through large-scale Indian Ocean tsunami exercises, known as IOWave exercises.

 

So far, seven IOWave exercises have been held (in 2009, 2011, 2014, 2016, 2018, 2020, and 2023). These exercises aim to test how quickly tsunami alerts are received and shared through national warning systems, and how well authorities respond according to their Standard Operating Procedures (SOPs). Throughout the IOWave Exercises, the engagement of coastal communities in tsunami education campaigns, preparedness measures, and evacuation drills has progressed.

 

In the Republic of Mauritius, the Mauritius Meteorological Services (MMS) is the designated National Tsunami Warning Centre. Mauritius has taken part in all the seven IOWave exercises since 2009, most of them full-scale events involving the MMS, Mauritius Police Force (MPF), National Disaster Risk Reduction and Management Centre (NDRRMC), Mauritius Fire and Rescue Service (MFRS), and other key partners.

 

IOWave25

IOWave25 is a simulation exercise designed to test how tsunami bulletins are received and warnings are broadcasted across national systems, and how different authorities respond according to their procedures in place. The exercise will take place on Wednesday, 15 October 2025, starting at 10:00 a.m. and ending later the same day.

 

IOWave25 will be carried out in collaboration with the NDRRMC, along with other stakeholders and participants from selected local communities in Mauritius, Rodrigues, and Agalega.

 

The public is advised to follow all instructions from the relevant authorities during the exercise.