People swimming at Ely’s picturesque Roswell Pits are ruining the area by leaving behind bag fulls of rubbish and intimidating other users.

A dog walker, who uses the area but wants to remain anonymous, claims he has felt initmated because of the large number of teenagers who use foul language and are “generally disruptve”.

He claims to have witnessed rocks and stones being hurled at dinghys belongong to Ely Sailing Club and said they are causing damage in a neighbouring farmer’s field by riding their motorcyles across it.

Gary Ungless, Ely Sailing Club’s commodore, admitted there had been problems with teenagers congregating around the pit but said the rubbish they leave behind is the biggest issue for the club.

“We were concerned about them jumping and diving off our pontoon into the water so we have removed that, because people have been dumping stuff like cycles into the pit and we didn’t want anyone getting hurt.

“The pit is relatively safe as far as swimming goes because it is relatively shallow and a clay pit so doesn’t have the weed problem associated with gravel pits.

“But because people have dumped things in the water you just don’t know what is down there. Fishermen have reported their lines snagging on things that haven’t been there before.

“The young people have caused a nuisance to the fishermen, but once it was pointed out to them they agreed a compromise and kept away from where people were fishing. They were also swimming out to one of the islands where birds were nesting, but again when they were asked to stop doing that they have.

“The real issue has been the rubbish they are leaving strewn everywhere. We have had a couple of clean ups and have collected sack fulls of cans and other rubbish - but no evidence of drug taking (thankfully).”

Mr Ungless added: “The reason people come here is because it is a beautiful area and you can swim. But it won’t stay beautiful for long if people dump rubbish everywhere.”

The dog walker added that while the problem of littering continues he will be forced to go elsewhere.

He added: “It is a lovely nature walk, but the environment has been spoilt. I counted hundreds of items when I was last there - all in the space of a couple of days.”