The emerald-green water in Bristol’s floating harbour shimmers invitingly in the warm morning sunshine. A group of seven swimmers check for signs of the harbour master, then for the third time this summer slip quickly into its cool, refreshing embrace, with delighted gasps and gentle splashes. “It’s so nice. I’m not usually a morning person, but this is like a shot of coffee,” calls Lindsey Cole, 38, before turning and flicking her mermaid tail to break the mirror-flat surface. Cole and others are not there just for pleasure though: they are deliberately flouting bylaws that prohibit swimming in the docks as part of a mild-mannered civil disobedience campaign aimed at securing public access to urban waterways in the city. “The people of Bristol should have the right to use their harbour as an amenity, so wild swimming is available to everyone in the city rather than being an exclusive pastime,” says Johnny Palmer, founder of the Swim Bristol Harbour campaign and owner, since 2018, of Bath’s Warleigh Weir wild swimming spot. The group would like to see a designated swimming area in the Cumberland basin section of the harbour, where the water quality frequently exceeds the Environment Agency’s “excellent” standard for bathing water. Urban bathing spots are the norm in many European cities. In Copenhagen, citizens can swim in four harbour baths in the city’s redeveloped docks. “The ultimate aim,” Palmer says, “is to have a floating lido filled with harbour water like in Copenhagen, but for now we could have lines marked out and better access to the water.” Since the group’s first protest swim last month, Bristol city council has announced that it is considering how to allow safe swimming in parts of the harbour, which was built in the 1800s to allow cargo ships to stay afloat permanently rather than rise and fall on the tidal waters of the Avon. But for now, it is opposing illicit dips, worried that inexperienced swimmers could get into difficulties in the deep, cold water. Growing enthusiasm for swimming in natural water is putting pressure on councils to increase access to waterways. Longstanding proposals for a floating pool on the Thames are progressing. Architecture practice Studio Octopi is about to carry out a feasibility study for one west London borough. Four other potential sites within the M25 include a 15-metre barge pool and a 50-metre pontoon pool. The firm is also working on proposals for floating pools in Liverpool and Belfast, as well as putting in bids to develop schemes in Ireland and Scotland. Founder Chris Romer-Lee believes there is scope to develop urban waterways: “Ten years ago, people would have recoiled at swimming in urban water; now they leap at the chance.” Bristol’s water safety partnership, led by Avon Fire and Rescue, is concerned Palmer’s campaign could encourage inexperienced or intoxicated swimmers into the harbour, where they could suffer cold-water shock and drown. “It sets the scene for people taking a dip after a few drinks,” says group manager Harry Awramenko. “It’s a working harbour, with boats coming and going. The water quality is variable. There is a risk of cold-water shock.” Over the past two years, Avon Fire and Rescue has dealt with more than 70 water related incidents, 26 resulting in serious injury or death. These include suicides and accidental falls. Awramenko accepts that a designated area, with lifeguards and emergency service access, could be safe: “We would discourage swimming in the harbour until measures are in place.” At the harbour, there is widespread support for the campaign. Alison Curtis, 51, says her husband learned to swim in the docks as a child, and her 72-year-old father competes in the harbour triathlon every year. “I think it would be great,” she says. Ian Jennings, 41, who is in the harbour to repair the hull of his boat, where he lives, is keen too. “As long as there is a clear channel for boats to come through, I don’t see why not.” Others disagree: boatyard owner Mark Rolt thinks swimming is too risky and a Copenhagen-style pool unaffordable. “I wouldn’t swim in the harbour,” he says, as he repairs a mast. “I think it’s dangerous.” The rebel swimmers are determined to keep going despite the threat of £1,000 fines. They concede that there are risks but believe a harbour baths could actually teach people to respect cold water – and offer physical and mental health benefits. “The way to keep people safe is not by saying, ‘don’t go near the water’,” says Kim Graves, 31, as she dries off in the sunshine. “There needs to be education.” She is pleased with the impact they’ve had: “There have been calls [to allow swimming in the harbour] for a long time – and we have got further than most in a few weeks.”