Lee Valley park ranger speaks on the dangers of "forbidden" swimming

We're diving deeper into the dangers of open water as figures 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.

Ranger of Lee Valley Country Park, Tom Oliver, tells Greatest Hits Radio river water is "always colder" than seas because the water is 'stagnant'.

This can often take swimmers by surprise, he says.

Swimming in the River Lee (and other Lee Valley Regional Park waters) is generally forbidden and against the byelaws, according to Lee Valley Regional Park Authority.

Tom recommends if you do want to swim, to join an open water swimming group:

'There are groups out there, it's a lovely thing to do, but under the right circumstances and right environments. The River Lee is not the right environment.'

'It's not safe to be swimming here. In an authorised group, all the considerations have been taken - where you go out, in, what to do if you're in danger, how to call the fire brigade.

The Fire Service advise that you are aware of the following risks:

• Cold water shock kills. The RNLI encourage people to "float to live", fight the instinct to thrash and give your body a chance to breath.
• Take notice and obey of warning and safety signs
• Stick to proper footpaths, riverbanks and cliff edges can be unstable
• Water and alcohol/drugs do not mix. Plan your route home away from water. 26% of people who accidentally drowned in 2022 had alcohol and/or drugs in their system
• Going out on your own? Let someone know where you are going and when you aim to return
• Never enter the water to rescue your dog, who will rescue you? Most dogs manage to scramble out - some owners are not so lucky
• Never enter the water if you don't know how deep the water is, or how fast the current is

They also advice that if you are taking part in outdoor water activities, do so in a designated area and find out about local clubs.

Weather can affect the water so check forecasts and tides before you go out.

Wear a lifejacket and make sure it's right for you and the activity.

Keep in touch - have your mobile phone with you, tell someone where you're going and when you'll be back.

And children should always be supervised by an adult.

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