Photo by Liam McGrath
Environmental campaigners are warning of a potential “catastrophic disaster” as plans emerge to dump 850,000 tonnes of contaminated sediment at sea as part of a £150 million redevelopment of Cornwall’s Falmouth Docks.
£150 million development at environmental cost
Falmouth Docks and Engineering Company and A&P Falmouth have applied for planning permission and marine licenses to modernise the historic docks, promising to accommodate larger cruise ships and support floating offshore wind development. The project could bring 200,000 passengers annually by 2030, boosting the local economy by £13 million and creating 350 jobs.
But the scheme requires dredging around existing wharfs to allow massive cruise vessels to dock alongside – a process that would disturb decades of accumulated toxic contamination from anti-fouling paints and industrial activities.
Toxic legacy threatens marine life
Environmental campaigner Sophie Miller warns that the dredging will release “plumes of noxious fine sediment” containing copper, mercury, and arsenic that were used as anti-fouling biocides on boats. “The dredging from the docks contains decades of toxic contaminants and will release plumes of noxious fine sediment that will likely contain copper, mercury and arsenic that were used as anti-fouling biocides on boats,” she said.
The dredged material would be dumped in Gerrans Bay, raising alarm among marine conservationists about the impact on the area’s unique ecosystem.
Rare maerl beds under threat
The dredging site sits on the edge of the legally protected Fal & Helford Special Area of Conservation, home to rare maerl beds – fragile coral-like algae that grows just one millimeter per year and provides critical habitat for marine species.
“Maerl grows at just one millimetre per year. Once buried by silt, it dies,” Miller explained. Critics say the developers have relied on outdated surveys from over a decade ago rather than conducting modern underwater assessments for a project of this scale.
Previous dredging proposals in Falmouth have been halted specifically due to concerns about maerl bed damage, with the Marine Management Organisation emphasising the need to protect these “ancient and rare” non-renewable resources.
Fishermen fear ‘catastrophic disaster’
Local oyster fisherman Chris Ranger, whose family has worked the Fal Estuary for generations, describes the threat to what may be among the last significant native oyster populations globally. “There is great concern for unique marine habitat within the Fal Estuary, including probably the last natural native oyster biomass forming a significant part of the 5-15% left globally,” he said.
Ranger warns that no amount of precautionary measures can prevent suspended sediment from spreading throughout the estuary: “No amount of precautionary measures will ever stop the suspended sediment from heading up and down the estuary, and they still want to dump it in Gerrans Bay, another catastrophic disaster for marine life.”
The concerns echo previous opposition from Cornish fishermen, who have cited examples of other fisheries completely wiped out by nearby dredging operations.
‘Green washing’ allegations
Environmental groups accuse developers of using floating offshore wind development as “green wash” to justify dredging primarily designed for cruise ships. Miller argues there’s no evidence that offshore wind infrastructure requires deeper harbors, noting that “offshore wind components can and are transported on vessels with shallower drafts than the ultra-deep cruise liners the dredge is actually designed to accommodate.”
She points out the environmental contradiction: “One cruise ship ticking over has the same emissions as a million cars” and would increase air pollution and sewage discharge in local waters.
Developers promise consultation
A&P Falmouth’s director of port development, Drystan Jones, says the company has been conducting public consultations and working with Natural England and Cornwall Council, which contributed nearly £1 million for environmental impact assessments completed in early 2025.
Previous contaminated dredging in Falmouth has required specialised treatment due to petroleum hydrocarbon contamination, with materials classified as hazardous waste under EU regulations.
The Marine Management Organisation is currently reviewing the marine license application (MLA/2025/00157), with public comments accepted until September 4. The controversy highlights the growing tension between economic development and marine conservation as Cornwall balances tourism growth with protection of its unique coastal ecosystems.