NEW warnings have been given about the danger of swimming in the deep water in Tytherington Quarry after hundreds of youngsters were caught trespassing last summer.
Security has been stepped up at the disused North Face quarry, with extra perimeter fencing erected, warning signs put up and security patrols with dogs introduced.
There have already been several recent incidents of trespass by people wanting to swim in the water.
But they have been reminded that as well as being on private land illegally, they also face the risk of injury or drowning.
FCC Environment, the recycling and waste management company that owns North Face quarry, has urged parents to warn their children about the dangers of swimming in unsupervised waters such as quarries, rivers, lakes and reservoirs, as well as the risk involved in tombstoning, the hazardous activity of leaping from a height into water.
Mark Cheetham national closed site manager for FCC Environment, said: “We understand the temptation to swim while the weather is warm. But we would like to emphasise that swimming at unsupervised sites like this is very dangerous as the water is still exceptionally cold and hidden rocks lie just beneath the surface.
"Sadly there are a number of tragic drowning accidents in the UK every summer."
He said after similar incidents last year, the company had taken action to try and keep people away.
He said: "Trespassing onto private land is against the law. We will continue to work with the police on this issue and anyone seen intruding on our site will be photographed and any vehicle details recorded with a view to prosecution.”
The action taken comes just weeks before schools break up for the summer holidays.
Last year, nearly 50 young people sneaked in on one day, with the police called out during another weekend after a group of 40 were discovered swimming and having picnics.
The depth in the middle of the water is 30ft and exceptionally cold. Among concerns are swimmers getting cramp and not being able to get out or be rescued, going into shock and drowning.