CHILDREN and adults have been warned not to try to cool off in the hot weather by swimming in the many gravel pits around Canterbury.

Police fear someone may drown if the practice continues. Last week four people died in the UK after jumping into rivers and lakes.

Steve Burke, who rents a nature reserve on the outskirts of Canterbury which has two deep lakes, said it was extremely dangerous to go in to cool off, even for very strong swimmers.

"The problem is that the water in these lakes is very cold all the time and the sudden change in temperature can cause the body to shut down," he said.

"There are also pockets of very cold water which people could swim into with the same result. Even strong swimmers won't stand a chance when that happens and if someone goes in after them the same could happen.

"Another problem in these lakes is weed. It is tough and stringy and difficult to break and a swimmer in difficulties just won't be able to get out of it."

Mr Burke has already seen many youngsters swimming in his lakes and using inflatables and has warned them of the dangers.

"We have a major problem and it is an accident waiting to happen," he said. "It is very worrying, especially as they ignore all the warning signs I have put up.

"Not only are the lakes very deep, with little visibility, one shelves steeply just feet from the shore and the other has 14ft of quicksand in it."

Between 2pm and 11.30pm on last Thursday Mr Burke's water bailiff turned out 30 people from the reserve who were swimming or using inflatables. Some had been drinking before they went in.

Not only do the swimmers ignore the warning signs they also climb over locked gates and fences to reach the water's edge.

"I can't blame people for wanting to cool off but this is not the right place," Mr Burke said. "They should use a swimming pool or go to the beach."

Mr Burke was so worried about the problem that he asked police to visit the reserve.

PC Linda Ritchie, youth intervention officer for Canterbury police's crime reduction department, has spoken to youngsters found at the lakes and sent letters warning of the danger to their parents.

She and her colleagues will patrol the area during the hot weather.

In 2001, according to figures published by Royal Society for the Prevention of Accidents, 276 people drowned in inland waterways in the UK, compared to 88 in the sea.