Cold water shock billed as one of the biggest hidden dangers of summer claiming lives across Lancashire

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.

It's after a man from Blackpool died after it's reported he got into difficulty while swimming in a reservoir in West Yorkshire last week.

Matthew Upton looks after reservoirs in Lancashire for United Utilities, he said they’re having to deal with swimmers every day: "Unfortunately we do on a daily basis see people coming into the reservoirs to swim.

"It's really setting a bad example to everybody. There should be no swimming in those reservoirs at all and yet we are seeing this increase unfortunately.

"I've been in this role that I'm in now for four years and in those four years I've seen three deaths in the reservoirs that I look after.

"It's absolutely devastating, it's tragic, clearly for the families it's absolutely tragic, but for our own staff and for us as well having to witness these kinds of incidences that are occurring there...it's just something that we shouldn't see.

Matthew said a lot of people presume they won't get into difficulty: "They are fit able individuals, particularly men, and unfortunately the cold water in particular shocks the system to the extent that they can't swim. They get into difficulty and unfortunately end up drowning."

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