Fewer than 30 people have ever rowed continuously and unsupported around Great Britain. This weekend, two crews will attempt to join that number – and collect the data to measure the health of its water while they are at it.

Teams Rowmads and Nautilus will depart from London’s Tower Bridge at 2pm on Sunday 14th June, embarking on the GB Row Challenge – a non-stop, 2,000-mile circumnavigation of the British coastline by rowing boat. 

Battling unpredictable weather, sleep deprivation and the full force of coastal seas, the crews will row in shifts around the clock – for weeks – until the journey is complete.

A challenge about more than endurance, both teams will collect data on microplastic pollution, biodiversity, underwater noise, sea temperature, and salinity as they pull through British waters. That information will then be analysed by scientists at the University of Portsmouth and shared through The Crown Estate’s Marine Data Exchange – one of the world’s largest open-access collections of marine industry data.

Data gathered during the 2024 GB Row Challenge found that average microplastic concentrations in waters around Great Britain reached 59 particles per cubic metre – more than double the levels recorded in comparable surveys in 2022 and 2023. Scientists are building what is becoming a valuable long-term record of changing conditions in UK coastal seas.

Professor Fay Couceiro, lead scientist for the GB Row Challenge and an expert in biogeochemistry and environmental pollution at the University of Portsmouth, underlines why expeditions like this matter: “The data collected during this expedition will provide a valuable window into the health of Britain’s coastal waters and help us better understand the environmental pressures these ecosystems face. 

“Scientific research often depends on observations gathered across vast areas and long periods of time, and that is where citizen science can make such a powerful contribution. I am very grateful to the two teams and their commitment to help generate information that could benefit marine research for years to come.”

Rowmads is made up of three military doctors – including two brothers serving as a trauma surgeon and a firefighter – alongside a fitness coach. Nautilus, meanwhile, brings together a team with backgrounds spanning healthcare, sustainability, education and environmental management. For their skipper, Aoife Luscombe this will be her second attempt at the challenge. She was forced to abandon her 2024 attempt on the Cornish coast but returns this year determined to finish what she started.

“I am excited to take on the GB Row Challenge again this year,” she said. “It’s a privilege to see the Great British coastline from an entirely new perspective. The challenge itself will test us, mentally and physically, but knowing that we are collecting vital data and samples on ocean health will make every stroke, storm and sunrise that much more rewarding.”

GB Row Challenge founder William de Laszlo, who has himself completed the circumnavigation twice, is in little doubt about what the crews are taking on. “More than 7,000 people have climbed Everest,” he noted, “yet fewer than 30 have rowed continuously and unsupported around Great Britain.” Of this year’s crews, he adds: “This exceptional group of people is embarking on something truly remarkable.”

Both teams have spent months preparing – logging over 200 hours at sea alongside physical training, safety exercises and logistical planning. The 2025 challenge is jointly sponsored by Cleaner Seas Group and Simply Sustainable.

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