Could services cope with unprecedented floods?

The exercise, which took place last summer, envisaged widespread flooding of coastal towns and city centres causing massive destruction and death.

It tested the readiness of emergency services as well as planning for post-disaster recovery.

The three-day "dummy run" involved teams at 35 locations across the UK.

Taking part in Exercise Triton 04 were 1,000 personnel from 60 organisations.

Climate change presents us with rising sea levels, more extreme weather and more frequent and widespread flooding Baroness Young

These included the Environment Agency's most senior flood defence and operation managers, chief police officers, strategy managers from local government and senior government officials.

They were faced with a scenario including high spring tides, storm surges and high winds sending massive waves on shore along the east and south coasts from the Humber to Southampton.

The coasts of north and south Wales were simultaneously hit by a west coast tidal flood.

The resulting disruption would have been worse than anything ever experienced in the British Isles.

Military aid

The experts had to decide how to react to the resulting massive flooding of coastal towns and city centres and disruption to homes, infrastructure, industry and business as people and livestock drowned.

As the "disaster" unfolded in real time, officials had to make critical decisions on issuing public warnings, evacuation and the release of information.

The exercise also tested contingency plans, support and resources, including military aid, for both dealing with the immediate crisis and helping with recovery in the longer term.

The Environment Agency said the exercise tested the full chain of command up to and including the processes required to secure emergency powers.

Environment Agency chief executive Baroness Young of Old Scone said: "Exercise Triton 04 tested the nation's ability to work together to deal effectively with a major flooding emergency and has put us in a better position to anticipate and manage all the consequences should they occur."

She added: "Climate change presents us with rising sea levels, more extreme weather and more frequent and widespread flooding. This is exactly the scenario we tested in Exercise Triton 04."