As the sun continues to shine, people enjoying the outdoors are urged not to cool off by swimming unsupervised in open water.

Staffordshire County Council says even the strongest swimmers can find themselves at risk from the sudden change between air and water temperature and hidden hazards beneath the surface.

Victoria Wilson, Staffordshire County Council's Cabinet member for Communities and Culture, said: "Now that everyone is out and about again and the weather is getting hotter I understand people wanting to cool off by going for a swim.

"But plunging into open water is completely different to swimming in a safe, controlled pool and can be very dangerous, even for experienced swimmers.

"Not matter how warm the day, large bodies of water stay very cold, with temperatures around 2O Celsius, and that can cause cold water shock, which can lead to a sudden loss of consciousness."

Swimmers in lakes and reservoirs are also at risk from becoming entangled in underwater weeds and dumped rubbish, or being caught out by unseen currents and other dangers.

For instance the floor of some reservoirs can shelve deeply and suddenly in places, while there can also be an undertow towards the pipe network carrying water away.

Victoria Wilson added: "We would urge people to use common sense: no matter how appealing a stretch of water looks 'no swimming' signs are there for a reason, please stay safe."