We have today reissued our drowning-prevention advice, having been shown video footage of a young man jumping into the Serpentine in central London during the heatwave at the weekend.
The video, uploaded to a Facebook group, shows a young man balancing on a post in the water and then eventually jumping off into the water. His friends are shown playing on a boat nearby.
The Brigade's Head of Community Safety, Chris O'Connor, said: "It's incredibly dangerous to jump into water like this because it's impossible to see hidden obstacles under the surface. It's very easy to slip and get into difficulties
"It's tempting to jump into water like canals, lakes and rivers to cool down during the warmer weather, but it's just not worth the risk.
"Sadly people drown each year and we'd hate for someone else to become another statistic for the sake of having a laugh or showing off to their mates."
The Brigade's statistics show that there have been 13 water related fatalities in London in the last three years.
In the summer months, the Brigade attends at least one water related incident a week and crews carry out an average of 30 water rescues every year.
The only outfit to wear in London's water this summer
In London, over the last three years, firefighters have attended 128 incidents involving people in water and carried out 92 rescues.
In April 2014 the Brigade was called to reports of a man who had entered the Serpentine and not resurfaced.
Rescue crews carried out a systematic search of the water and the man was sadly not found and his body was recovered from the water the next day.
The Brigade's water safety advice is as follows:
National figures show 338 people died from accidental drowning across the UK last year and Chief Fire Officers Association
figures show: