The quest to stay cool in a heatwave can entice many to water.

With schools out for the summer, the general warning to keep youngsters safe and highlight the dangers of playing in reservoirs comes into practice once again.

Swimming in the local baths is by far the safest option – not in places which, for swimmers, are out of bounds due to the potential dangers that lurk there.

Yet, it seems, people are still prepared to take the risk by swimming in open water such as reservoirs.

According to Matt Thompson, from Yorkshire Water which operates 120 reservoirs across the region, 15 people were recently caught swimming in one of their local reservoirs. “Basically it is a hard line, but it is true, if people continue to swim in our reservoirs it is a matter of time before somebody dies.”

Matt explains that while the water may appear calm and still, there is an underwater pipe siphoning off water to the treatment works producing a slight current. He says the water is also colder than expected which can massively impact on the body’s vital organs.

He says it doesn’t matter about being a good swimmer – often people drown because the water, which can be between 15 and 22m deep in some reservoirs, is so cold.

“You have no chance really. It is incredibly dangerous and I would add in to the fact that we know, because we have caught people drinking, that alcohol comes into it as well and it is just dicing with death,” says Matt.

A concerned passer-by recently sent an image to the T&A of a group of youngsters in a paddling pool floating in the middle of Chellow Dene reservoir – the same location where 22-year-old Aamir Ahmed of Heaton drowned just over three years ago.

The image lays bare the reality that people are ignoring the warnings and are still putting their lives at risk.

Ian Bitcon, senior fire safety officer with West Yorkshire Fire Service, says: “We know year in, year out, people will go into reservoirs and our advice is the water will be colder and even the strongest swimmers will become very tired.

“We know that happens, likewise it doesn’t matter what the surface looks like, they have no idea what is under the surface.

“We attend incidents where people dive into the water, hit something or get entangled on something which leads to them drowning.

He also warns of the potential dangers of rescuing pets. “People occasionally go into the water to rescue pets. If a dog is in trouble in the water, you can guarantee as soon as you go in, you will be in trouble as well.

“Just don’t go into the water. You don’t know what is there. You don’t know the temperature and you could end up getting in trouble very quickly.”

Paul Mudd, acting director of Operations at Yorkshire Ambulance Service NHS Trust, says: “The county’s many waterways are popular destinations for people during the summer months, which can make them dangerous places for those who take risks.

“It may be very appealing to jump into the water to cool off on a warm summer’s day, but people need to be aware of how dangerous it really is. Water can look calm on the surface, but contain unseen debris and, rivers in particular, can have treacherous undercurrents.

“Although it is banned, people are also often tempted to swim in reservoirs without realising that there is automatic equipment located under the surface which can operate without warning and cause dangerous hidden currents.

“Furthermore, the temperature of deep water is much colder than people would expect and, even on a hot summer’s day, rarely getting above freezing. This is cold enough to take your breath away, which is the body’s natural reaction and cannot be controlled, possibly leading to panic and drowning. Cold can also make your arms and legs numb which means you can’t control them to swim and can also lead to hypothermia – a serious reduction in body temperature -– which can cause heart failure.

“Several lives have already been lost this year across the UK and we don’t want to see anyone else hurt or injured, so the message is simple – enjoy the summer, stay out of open water and stay safe!”