The next ferry is due to leave the Saint Malo ferry terminal in an hour. Passport checks are being carried out slowly, just before embarcation. The Channel crossing begins here in a relaxed atmosphere, with the sound of seagulls in the background. The sea will then carry the ferry on its slow journey to the opposite shore in England, and it is almost hard to believe that in the middle, somewhere between one wave and the next, it will cross a border.

In a few dozen kilometres, however, France’s territorial waters will give way to British. This reality, that no-one paid much attention to any more, has become a huge cause for concern on Brittany’s coast in the last few months.

Will Brexit build a wall across the Channel?

In this corner of western France, several businesses and communities risk suffering the consequences of the referendum of 23 June 2016, beginning with the sector most dependent on the Atlantic currents.

Brittany is France’s leading fishing region, but half of its fishing vessels work in British waters. At the Lorient port (the country’s biggest in terms of the value of the catch), the situation is particularly alarming. The deep-sea fishing companies – such as Scapêche, the biggest, which employs 250 sailors and officers – are dependent for 80 per cent of their activity on the United Kingdom’s Exclusive Economic Zone (EEZ).

They are so dependent that “to move their deep-sea fishing away from the English zones is just inconceivable,” said Sylvain Provost, president of Scapêche, in an interview with the daily paper Les Echos.

But although trawlers have been allowed to navigate British waters so far, thanks to the Common Fisheries Policy (CFP), one of the European Union’s (EU) most successful policies, the question now on the table is what will happen when London signs off on its official departure from the EU?

“In the negotiations that will be taking place in Brussels, our seafarers have the most to lose,” says Olivier Le Nezet, president of the Regional Committee of Maritime Fisheries and Marine Livestock (CNPMEM), speaking in Rennes.

Brittany, with its 22 ports, 5,000 seafarers and 600 enterprises in the sector, fears its fishing zones will be greatly restricted. Several boats will be forced into French waters, without there necessarily being any room for them.

But being banned from accessing British waters is not the only possible risk arising from Brexit.

“The 27 member states are going to negotiate together with the United Kingdom, but after that, will there be negotiations within the EU? The Spanish have always considered the fishing quotas set by the CFP too favourable to France,” says Le Nezet, a former fisherman who had to leave his boat after 24 years in the business.

“If it hadn’t been for cancer, I would still be out at sea, and not here, dressed like a penguin!” he says, before getting into his car to head off to his next meeting.

The Bretons say that despite this crisis they still have a few cards up their sleeve: the European Commission’s negotiator for Brexit is a French man, Michel Barnier, former Minister of Agriculture and Fishing, but above all the president of the Brittany region and former mayor of Lorient, Jean-Yves Le Drian, has just been appointed by President Macron as the Minister for European and Foreign Affairs.

The new head of state went to Lorient at the beginning of June, accompanied by Mr. Le Drian, to meet Brittany’s fishermen. On board the trawler Breizh, Macron promised to respond “with action”to the seafarers’ demands, notably during the Brexit negotiations.

Concern among France’s British community

Fishers are counting therefore on the authorities in Brussels and Paris to make their voices heard, but that is not the case for the 13,000 British residents of Brittany, who are not hopeful.

Like their compatriots living elsewhere on the European continent, these expatriates from the United Kingdom were fearful when they learnt the result of the referendum. If the freedom of movement that is currently one of the pillars of the EU is up for negotiation, they may have to leave the little villages of Kreiz Breizh (Central Brittany), where so many of them came to live from 2000 onwards and where they represent up to a third of the population.

For over 15 years Maggie Fee has lived on the outskirts of Gouarec where there are less than 900 inhabitants. “We don’t know what the outcome of the negotiations will be,” she says, shrugging her shoulders. Then, distraught, she continues “Personally, I have applied for French nationality, but since it is a long procedure, I have also had to ask for a residence permit.”

This woman with long blond hair is a member of the Kreiz Breizh Integration Association (AIKB, founded in 2003), which helps new arrivals to learn French and deal with local bureaucracy.

“Several members of the AIKB sold everything they had in the UK before coming here. They would not be able to enjoy the same quality of life if they went back,” says Maggie. She left the UK to “change my life” and “get out of the rat race”.

If the British community were to leave these isolated villages today, the local authorities would face the risk of depopulation, with a direct impact on the local economy.

Furthermore according to a study by the Economic, Social and Environmental Council of Rennes (CESER) commissioned by the Brittany region and published in December 2016 “Brexit and the departure of residents could have an indirect effect on public services in Central Brittany”. Not only will these small districts lose some of their local tax income and their General Operating Grant (DGF) linked to the population, but also some schools may have to close some classes.

Brittany has about 10,000 second homes belonging to British nationals who head south of the Channel for their holidays. Hence the fall in the value of the pound is another source of worry for the Rennes authorities.

Since June 2016, the British currency has fallen by 15 per cent compared to the euro, resulting in a loss of purchasing power for those who receive their salary or pension in pounds, and for tourists from the UK, who are the largest group of foreign visitors.

Jean-Marc Roué, CEO of the cross-channel ferry company Brittany Ferries has followed this issue very closely. Based in Roscoff, off the northern coast of Brittany, his enterprise earns 80 per cent of its income in pounds, but pays 80 per cent of its costs in euros.

“I don’t have a strategy at the moment. All I can do is wait and see what the Brexit terms will be,” he explains, adding that “new tariff barriers will very probably have an impact on freight,” while “a further fall in the pound could reduce the number of British passengers”.

The ferries that sail from the ports of northern France risk suffering from this, while the island they are sailing to is becoming more distant.

“What I see so far is that Europe is losing a major country, that was at the heart of European industrial development, which fought against Nazism, which in short is at the root of the creation of Europe,” says Jean-Marc Roué, who describes himself above all as “a European citizen and entrepreneur” who hopes that after the UK leaves the EU “will not close in on itself like an oyster” but “will find the strength to re-launch the European project”.

A political godsend?

The Brittany Ferries boss is not the only one to hope that Brexit will in the end have some positive outcomes. The Breton Democratic Union (UDB), the local independence party, hopes to take advantage of the moment to forge closer ties with its European partners, notably with the Scottish National Party (SNP) and with Plaid Cymru in Wales, to political parties disappointed at the outcome of the referendum.

This summer, Scotland will be the guest of honour at the Lorient Inter-Celtic Festival (which attracts over 700,000 people to the town every August). A source close to the organisers has let it be known that the speakers will include Alex Salmond, former First Minister of Scotland and former leader of the SNP.

“He will come to talk politics,” says the source, enthusiastically. Wales, meanwhile, sent a delegation from Cardiff representing its First Minister in March for talks with the Rennes authorities, and test out the ground with a view to possible post-Brexit agreements.

CESER president Jean Hamond, who attended the meeting with the Welsh delegation, confirms that “there is a wish for region to region links” and that the Cardiff authorities “naturally turn to their Celtic neighbours”.

The White Paper, published at the beginning of the year by the Welsh government and Plaid Cymru, seems to confirm this scenario, arguing for a “four nation approach” to Brexit, namely negotiations in which “the three devolved legislatures and administrations participate on equal terms with the UK Government, representing the interests of England”. In which case, the “Celtic neighbour” across the Channel could well have a role to play.

That would satisfy Jen-Yves Le Drian who, in 2015, talked about wanting to “develop Breton diplomacy and its attractiveness within Europe”.

Even if Brittany does get its voice heard in Brussels and defend its interests in the negotiations, the departure of the UK from the EU will nonetheless widen the gap between the two shores of the Channel.

The ferry journey across this stretch of sea that has seen several crucial moments in the history of Europe and is the cradle of one of its founding myths, that of King Arthur and the Knights of the Round Table, will not take any longer after Brexit, but that border in the middle of the waves could be a lot more visible.