A planned test of Portland’s flood sirens has been cancelled as conditions are “too similar to the real event.”

The Chiswell sirens were due to be tested by the Environment Agency (EA) today to prepare for any floods this winter.

Yesterday the Environment Agency announced the tests had been cancelled, saying: “Conditions are too similar to a real event which could have caused confusion.”

Residents are warned that if they hear sirens sounding today, they should assume it is a real event. The Environment Agency had informed residents of the planned routine test through visits and leaflets.

Rachel Burden, from the EA, said: “Regular siren testing is an essential part of our forward planning, not only to ensure we are incident ready, but also to make sure our community flood warning and informing measures are effective.

“If severe storms hit Portland, the sirens will play a crucial part in alerting local residents to imminent danger and potential evacuation. Ultimately, these sirens could help save lives.”

Chiswell was badly affected by the floods in 2013 and 2014. It is a vulnerable area and can take a heavy thrashing from the sea when south westerly winds pick up.

The Environment Agency says although good flood protection measures are in place, the public can never fully defend against the worst conditions that nature can throw.

The sirens, tested twice a year, are extremely loud so they can be heard above the noise of crashing waves during a storm. Modern sirens were installed in 2010 and replaced older Second World War equipment. An additional siren was installed in 2015 to fill a ‘quiet spot’ identified by residents during testing in 2014.

The day supports the annual Environment Agency Flood Action campaign. This year it runs from November 29, and is aimed at 18 to 34 year-olds - the age group least aware of flood risks.