Anthony CarrollA major disaster exercise is being held in Great Yarmouth this morning as the Environment Agency simulates an incident in which a ship has destroyed a flood defence wall.Anthony Carroll

A major disaster exercise is being held in Great Yarmouth this morning as the Environment Agency simulates an incident in which a ship has destroyed a flood defence wall.

Exercise Marsh Harrier will test how quickly a temporary flood defence barrier can be put up to protect households in Southtown Road and other areas from being flooded.

From 4am to 8am Environment Agency staff will be working at the flood defence wall at Bollard Quay which for the purpose of the exercise has been demolished by a ship during a tidal surge.

The exercise has been organised in the early morning to see how staff react to working in dark conditions as they put up the temporary defences.

As part of the exercise all of Yarmouth's floodgates will be closed.

Nick Hesp, the agency's operations for Norfolk and Suffolk, said: 'The Environment Agency responds on average twice a year to shipping damage - thankfully a lot less drastic than what we are simulating in Yarmouth.

'It is important to ensure resources are in the right place to this type of emergency and is a good test of our readiness.

'We will endeavour to keep disruption to a minimum throughout this exercise and thank local communities for their cooperation and patience.'