Flash flooding has hit the Battle of Britain bunker at RAF Uxbridge.

Flood water cascaded into the underground facility on Monday morning during torrential rain.

It was largely held back by double doors at the foot of the main stairs  – although at one point the water was waist deep, according to Sqdn Ldr Richard Willis of RAF Northolt, who oversees RAF heritage in the borough.

“Fortunately the fire doors which are designed to hold back smoke held back a lot of the water,” he said. “Thankfully it has not reached the plotting room but it was above waist height at the bottom of the stairs.

London Mayor Boris Johnson visits the Battle of Britain bunker at RAF Uxbridge
 

“Contractors are on site and will be there overnight pumping out. Let’s hope we don’t get any more rain, although it looks as if we might. It was the sheer volume of rain, all coming at the same time. It just overwhelmed us.”

Mr Willis said bunker volunteers of 30 years’ standing had never seen anything like this morning’s flooding. Small amounts of water have entered in the past, during exceptionally heavy rain, but this was unprecedented, he said.

The bunker is home to the iconic plotting room from where the Battle of Britain was directed, where Churchill visited on several occasions during the Second World War and where he first made his famous remark: “Never in the field of human conflict ....”

All booked visits to the bunker this week have been cancelled, and a planned open weekend this weekend, where the public could turn up without an appointment, has been abandoned too.

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