Major concerns have been raised about the effects of a grey, sludge-like substance being discharged into Cornelian Bay.
The problem, which appears to be getting worse, is believed to be coming from a broken Yorkshire Water pipe which carries waste from the McCain factory out to sea.
Scarborough fishermen are worried about the lack of fish between Scarborough and Filey, labelling the stretch of water “barren”.
And the issue has also set alarm bells ringing with dog walkers, such as Peter Snow, of Folkton, who recorded these shocking images.
He said: “There’s no limpets on the rocks and no seaweed. A year ago it was crystal clear, but six months ago the kelp started dying.
“There were only stalks left, but now they’ve withered and gone. The rocks are covered in a white slime and it stinks. There must be thousands of gallons of that stuff going out there.”
Mr Snow has also seen water bubbling up among the rocks and when he felt the temperature of the water, it was warm.
He filmed a video of the scene, which shows the full scale of the problem and can be viewed at www.thescarboroughnews.co.uk
Scarborough and Filey Fishermen Society have contacted a number of agencies about the issue, including Yorkshire Water and McCain.
Spokesman Bob Roberts said: “McCain are fully recognisant of the fishermen’s concerns and have offered to fund an independent study by Cardiff University, possibly supported by Hull University on the local campus of the effect of the discharges over a prolonged period into the sea and how its dispersed along the coastline also its effect on marine life, along with water quality and seabed conditions.
“This was welcomed by the fishermen as a major step forward into allaying any fears on the impact of the discharges since they commenced from the long outfall pipeline in 1998.”
Mr Roberts said the group had been campaigning since 2009 to have some kind of say in what is being pumped out into the sea.
Bill Bartlett, corporate affairs director at McCain, said: “During the meeting the fishermen outlined their perspective and we were also able to explain and demonstrate how we use water and then clean it and how our strict monitoring regime ensures we operate in full compliance with our Environment Agency consent and all other regulations.
“We’ve been in Scarborough a long time and always sought to work with the community as a responsible employer and neighbour. So as part of this commitment, following our discussions with the fishermen, we are collating data from previous scientific studies and looking at options for obtaining more through research undertaken in co-operation with them.”
A spokesman for Yorkshire Water said: “We are aware of a leak on one of our outfalls that discharges organic waste into the sea. It does not pose a risk to public health. While the majority of the organic waste – predominantly starchy water – is discharging from the end of the outfall as it normally would, some is escaping closer to the shoreline and not dispersing as quickly as we would hope.
“We have informed the council and are working with the Marine Maritime Organisations to obtain the necessary licences to carry out a repair, after which we will be appointing an accredited specialist company to assist with cleaning the foreshore area.” He added that repair work would begin as soon as a public consultation had been carried out by the Marine Management Organisation.
Yorkshire Water said: “We would like to reassure local residents that we are working as fast as we can to remedy the situation.”
Both Cornelian Bay and Knipe Point as classed as Sites of Special Scientific Interest (SSSIs).
The law prohibits certain activities in SSSIs and lays out duties on how they should be managed and protected.
It is an offence to intentionally or recklessly damage, disturb or destroy land known to be an SSSI or intentionally or recklessly disturb the wildlife.
A spokesman from the Environment Agency said it was their understanding that work was currently being done on the long outflow pipe from McCain, so the visible discharge could be down to the short pipe being used instead. The spokesman said they did not believe the matter to be a dangerous pollutant, but that they would be speaking to Yorkshire Water and looking more closely at what is happening in the Cornelian Bay area.