Over £2,000 worth of destruction has been caused at Lake Wood.
The Woodland Trust, the charity looking after Lake Wood, are now facing the bill.
The Trust says the harm has been caused by campers leaving litter and broken glass.
Lake Wood is a celebrated beauty spot, with ancient woodland, rock outcrops and a lake providing homes for local wildlife.
However, there has been an increase in summer parties and camping at the site.
The conservation charity believe this led to the rise in litter and vandalism.
They say many visitors have been throwing rubbish over the 20ft cliff and into the lake the below.
A boat has been hired previously to fish the debris from its depths.
The lake overflow pipe has also suffered extensive damage, and meant water levels have dropped.
The charity say the resulting emergency work will potentially add another £1,000 onto this summer’s bill.
Damaged safety fencing also needs to be completely replaced, totalling a further £1,500.
Campfires have caused particular alarm with The Trust, as they not only scorch the soil, but could catch and spread in drier weather.
David Bonsall, site manager for the Woodland Trust said:
“Lake Wood is a stunning location, and is a precious habitat that we at the Trust have worked hard to safeguard and restore.
“We don’t want to see it ruined by mindless individuals.
“I’d urge anyone who sees damage being done to contact ourselves and local police.
“Any help people can offer by litter picking during their walks is very much appreciated.”
Lake Wood is a 19 acre site.
It is home to dormice and almost 60 species of bird, including kingfisher and heron.
Camping, fishing and barbecues are not allowed at Lake Wood.
The local police can be contacted by phoning 101.
Reports regarding the site can also be sent to [email protected] .