A brave pub punter dived to the rescue when a woman motorist ended up submerged in raging water after attempting to negotiate a flooded road.

Colin Dunn pulled the 24-year-old from her sinking car after a flash flood caused by Monday’s torrential rain created a seven feet deep river under Wallington railway bridge.

Mr Dunn, 39, was celebrating his niece’s birthday at O’Neill’s pub at 6.30pm when he heard shouting.

He saw the desperate woman, thought to be from Coulsdon, struggling to get out of her purple Nissan Micra which was almost entirely submerged.

Mr Dunn, who used to run a boxing club for children in Wallington, immediately jumped into the river – a mixture of rain and sewage.

He said: “There was a lot of people watching and there was someone already in the water, so I decided to just run from where I was and jumped in the water too.

“She was really desperate inside the car, because she couldn’t open the door and she thought she was going to drown. I couldn’t open the door on my own, so this other chap came to help.

“I was desperately trying to get to the back of the car because there was something white floating there and people were shouting it was a child. But it turned out to be just a pillow.”

After the rescue, Mr Dunn and his friends took the terrified woman to the John Jakson pub across the road and gave her cups of tea.

She was kept warm by the pub customers while she waited for an ambulance and a friend to arrive.

He said: “It was horrible. We were all being sick because of the disgusting water and the lady was pretty shocked. She couldn’t even speak, but we were trying to calm her down.

“We also wanted to talk to the other chap who got in the water, but he disappeared after we got her out.”

As the torrential downpours continued, the fire brigade sealed off the area around Manor Road, resulting in traffic disruption near the station.

Nick Morley, crew manager at Norbury fire brigade, said: “Apparently the woman had seen another car get through the waters, so she started driving under the bridge.

“At some point her engine must have stalled and the water was gradually filling up to the roof.

“When we arrived a member of the public was swimming out to assist her. A big crowd was watching because it was quite spectacular. "People were saying there was a baby trapped inside, so that was our first concern, but it turned out there was no one else in the car.

“We found the woman looking wet and bedraggled in a local pub. She was given first aid but was OK and someone came to pick her up.

“I would advise anyone encountering three or four inches of water at the railway bridge in future to turn back because it is simply not worth it. Drinking contaminated water can also be very dangerous.”

The rescue comes two years after a local barber stripped to his underpants to rescue a pensioner trapped in a waterlogged car beneath the same railway arch.

Evan Jaffer Mohamod, 20, clung to the vehicle as it was dragged 20 metres during the worst floods in 60 years.

He was later commended for his bravery by the London Fire Brigade.

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