Cornwall Wildlife Trust has raised fresh concerns over the proposed £150 million redevelopment of Falmouth Docks, after investigations of environmental data by Trust staff suggested that sediment contamination testing for planned dredging operations could be far too limited to reliably identify sediments unsafe for disposal at sea.  

Data from three quarters of core samples taken across the site suggest contaminant concentrations unsafe for disposal at sea, with heavy metals including mercury, zinc, lead, copper and tributyl tin found at levels up to 176 x higher than safe thresholds. The Trust believes the sampling undertaken for the project lacks the detail needed to reliably distinguish contaminated sediment from material that may be suitable to be disposed of at sea, and therefore that the risk of introducing highly toxic pollutants into the Fal Estuary and Falmouth Bay during dredging remains unacceptable. 

Dan Barrios-O'Neill, Head of Marine Conservation at Cornwall Wildlife Trust, says:  

"We understand that the Docks need redevelopment. The Docks are an important employer and a vital part of Falmouth's history, culture and identity. We do not want to see the Docks decline, but redevelopment must be done carefully, and in a way that protects this extraordinary marine environment for future generations. 

“Sediment sampling carried out in preparation for the project appears inadequate, lacking the resolution needed to reliably determine which areas are dangerously contaminated and which are safe for disposal at sea. 

"Right now, the data simply cannot assure us that the organisations in charge can redevelop the Docks in a safe and sustainable way."  

The Trust warns that if dredging is not undertaken exceptionally carefully, contaminated sediments could be disturbed, allowing toxic chemicals to enter the water column and spread through the estuary, potentially affecting the wider Fal, Falmouth Bay and offshore disposal grounds. 

Dan added: 

"Speeding up decisions must not mean weakening environmental safeguards, particularly in an area like the Fal. The marine ecosystems here are nationally important, supporting irreplaceable maerl beds, seagrass meadows, kelp forests and the Fal’s unique and important sustainable native oyster fishery. 

"If dredging is not done right, the impacts could be far and wide. The incredible wildlife and habitats that led to this area receiving international protection could be damaged, putting at risk both the marine environment and the local livelihoods of many people, from the traditional oyster fishers working in the Carrick Roads, to the trawlers in Falmouth Bay, to wildlife tour operators in Falmouth.” 

The Government has designated the Marine Management Organisation (MMO) as the lead environmental regulator for the project through a fast-tracked process. Cornwall Wildlife Trust says that while it understands the need to improve and secure the future of the Docks, accelerating decisions must not come at the expense of robust environmental scrutiny. 

The Trust says these concerns are shared by many of the people whose livelihoods depend directly on a healthy estuary. Around 130 people attended a recent public meeting organised by the Stop the Dredge campaign, including commercial fishermen, native oyster fishers, local business owners and residents. Many raised concerns that contaminated sediment could be carried by tides through important fishing grounds if dredging is not managed with sufficient care, potentially affecting the Fal's internationally renowned native oyster fishery as well as crab, lobster, scallop and other shellfish fisheries. 

The Fal and Helford Special Area of Conservation is internationally important for biodiversity and blue carbon habitats, including England's largest and best maerl beds and extensive seagrass meadows. It is also home to extensive and dense kelp forests and Europe’s only remaining traditional native oyster fishery. Species protected under the Wildlife and Countryside act 1981 including native oyster, giant goby and the spiny seahorse. The estuary and bay are also home to protected cetaceans such as common dolphin, harbour porpoise, Rissos dolphins, fin whales, many important seabird species and Atlantic grey seals. These species all depend upon the health of the estuary, alongside important commercial fish and shellfish species including lobster, brown crab, scallops, bass, pollack, thornback rays, and many more.  

The area is already under pressure from climate change, declining water quality, agricultural runoff and increasing human activity. Cornwall Wildlife Trust says contaminated sediment released during dredging could place further stress on ecosystems that are already vulnerable. 

Matt Slater, Marine Conservation Officer at Cornwall Wildlife Trust, says: 

"Contaminated material on the seabed isn't neatly separated into clean and dirty layers. Toxins are inconsistently distributed throughout the sediment, making it extremely difficult to distinguish safe material from contaminated material without much more detailed sampling. 

"The area of the dredge is 232,500 meters squared – this is equivalent to 32 football pitches, within this large area only 21 sample cores have been analysed. The huge areas between the samples mean that there could be contamination hotspots that have simply been missed.   

“When disturbing deep sediments like this that have built up over centuries, it is impossible to eliminate the risk of creating plumes of disturbed silt which would be carried with tidal currents, spreading new contamination with a huge impact on marine life."

The Trust is also concerned about the potential impact of approximately 50 weeks of pile driving during construction. It says underwater noise could significantly affect harbour porpoises, dolphins and seals that regularly use the estuary, with more recent acoustic monitoring indicating marine mammal activity is greater than is reflected in the Environmental Statement. 

Cornwall Wildlife Trust has previously submitted a Holding Objection to the Marine Management Organisation (MMO), citing concerns over contaminated sediments, underwater construction noise and the potential impacts on protected habitats and marine wildlife. 

Further environmental analysis is expected in the coming weeks, while Cornwall Council's Strategic Planning Committee is due to make a decision on the shoreside planning application for the scheme on 20 August.  

Although the public consultation is now closed, members of the public can contact the Marine Management Organisation quoting Licence application reference MLA/2025/00157. 

Learn more about the redevelopment plans