Cold water shock billed as one of the biggest hidden dangers of summer in Gloucestershire
We're diving deeper into the dangers of open water
We're diving deeper into the dangers of open water as we reveal one child a week dies from drowning in the UK.
Safety experts say so-called 'cold water shock' can kick in within minutes when the water's 15 degrees celcius or lower.
That's pretty much the temperature of ALL rivers, lakes, and reservoirs in Britain during the summer.
Accidental drowning has claimed 27 lives in Gloucestershire over the past five years.
67% of them involved men, 33% of incidents involved women - and 48% of deaths were of people who didn't intend to enter the water.
Helen Bowker-Steer, Commercial Manager at the Royal Life Saving Society, said: "Cold water shock is a huge danger in open water.
"People forget about it because they put their foot in and it feels warm but as you go further into the water it gets colder.
"But as you deeper into the water the rest of your body will cool down which is when you experience the shock."
Helen Bowker-Steer added: "We have a huge issue with cold-shock. People will hit the water and cold-shock will be the first reaction.
"We've also got other hidden dangers like things underneath the water. So weeds and reeds which you can get trapped in.
"You can get trapped in those and once the panic sets in that can get worse."
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