At 5.30pm in Manchester’s Piccadilly Gardens, three police officers are gathered around a wheelchair parked in front of a gold postbox commemorating Team GB’s Olympic cycling success. Sitting in the chair, bent double, is a tiny woman with one leg. “Can you sit up, love?” the officers ask, coaxing her gently upright. They know her name. “We just wanted to check you were OK.” She mumbles that she’s fine. As they head off towards the statue of Queen Victoria, the woman immediately slumps forward again.

On a bench near the tram tracks, another drug casualty is frozen – a different kind of statue. He is holding a rolled-up cigarette, long extinguished in the evening drizzle. In a doorway by a branch of Greggs, three men with sleeping bags are sharing some pasties. In front of them, a preacher with a megaphone is telling commuters to repent or burn in hell. Outside Boots, two charity fundraisers working for Shelter flirt with commuters on their way up to Piccadilly station.

Welcome to the civic square that makes the news for all the wrong reasons. On Thursday night, a 19-year-old man was taken to hospital after being assaulted in Piccadilly Gardens by a man with a broken bottle. This came a few days after four homeless people were stabbed in a fight at the Market Street end, and six days after a 15-year-old was stabbed.

Piccadilly Gardens’ benches and grassy areas have become a magnet for homeless people and all-day drinkers. Photograph: Christopher Thomond/The Guardian

Now, 18 years after councillors took the postwar “sunken” gardens out of Piccadilly Gardens and flattened them to make a chaotic, hybrid no-man’s land, Manchester city council (MCC) has vowed to restore the area and make it a source of civic pride. Earlier this week, it announced the appointment of architects to lead on the revamp, which it said would “help deter anti-social behaviour” and create a more “family-friendly” space. With that, it set up a test case for a vital question in modern cities: can you drive behaviour by changing public spaces – or merely get distracted from the underlying problems?

LDA Design will produce several plans that will go out for public comment in the spring, with the hope that the new and improved Piccadilly Gardens will be finished by the end of 2022.

LDA’s director, Mark Graham, knows the huge task must prioritise public safety. “It’s about taking opportunities away for unsafe things to happen,” he said. “Simple things like lighting and taking certain hiding places out, by which I mean the higher walls and corners and edges that don’t necessarily need to be there and which provide spaces for antisocial behaviour.”

One particular wall in Piccadilly Gardens has become notorious among Mancunians. When the square was last overhauled, in 2002, it received the controversial addition of a concrete pavilion designed by the Japanese architect Tadao Ando – his only UK work. The pavilion, housing a restaurant, is less contentious than its accompanying slab of concrete, dubbed Manchester’s Berlin Wall by its many critics, which not only provides shade on rare sunny days but also, many say, sanctuary for antisocial behaviour.

How it used to look: LS Lowry’s depiction of the demolished gardens, ‘Piccadilly Gardens, 1954’. Photograph: Manchester Art Gallery

Richard Leese, the council leader since 1996, is a fan of the pavilion but accepts he is a minority voice and that the wall will probably go. He is less keen to accept the area’s reputation as a no-go zone. “I just don’t get it. I’m a 68-year-old bloke, I’m the sort of person who is supposed to be petrified of spaces like that and I just am not,” he said.

Leese wants to move the bus station but is loath to remove the grass, despite it being a regular topic of despair in the Manchester Evening News. Get rid of it, argues Eddy Rhead, co-founder of the Manchester Modernist Society: “I can think of no other world-class public square in the world that has grass and yet MCC continue to replace the grass, only for it be destroyed by people, heaven forbid, actually using the square for recreation or – as was the case this winter – with the woeful Christmas markets.”

Rhead believes the architecture is a convenient scapegoat: “The biggest and hardest problem, and the one civic leaders seem unable to face up to, is to solve the wider social issues that currently make Piccadilly Gardens an unattractive space. Stop blaming the architecture … for wider social ills.”

The architect Liza Fior – whose practice, muf, won the 2008 European prize for public space for a town square in Barking, east London – says changing longstanding behaviour is difficult. Getting rid of what she calls the “stains of use” is not easy: she notes how Charles Booth’s Victorian poverty map of London “describes pockets of crime some of which persist until now, eg there is a little triangle off Old Street where there is a lot of street robbery and it was always thus.”

Manchester’s ‘Berlin Wall’. Photograph: Christopher Thomond/The Guardian

Kate MacDonald, MCC’s city centre strategic lead, is leading on the social side of the revamp. She works with Manchester’s street community – she knows the one-legged woman in the wheelchair “very well” – and wants to make sure they are not simply shunted elsewhere and forgotten about.It’s a complex picture, she says, backdropped by cuts to police and social services.

“But we do get people congregating in Piccadilly Gardens who make other people feel uncomfortable,” she acknowledges. She hopes to complement the new architecture with a team of friendly “hosts” who will welcome visitors and be trained to help rough sleepers and drug addicts.

She has already sanctioned the removal of some benches near the gold postbox after observing that they were never used by older shoppers but by drinkers (who now rest their cans on a huge new bin). When redesigning Gillett Square in Dalston, east London, Fior was unable to banish the street drinkers but worked to outnumber them. “We introduced a mirrored box of ‘loose parts play’ which is opened up for play sessions three days a week, so that instead of the street drinkers dominating, they become are a smaller percentage of activity,” she says, noting that the presence of children makes “a huge difference”.

Macdonald is keen to introduce more regular activities into Piccadilly Gardens, such as a community choir, and her dream is that by 2023 the square will be on every tourist’s itinerary. “Architecture on its own can’t change everything, but it can support a new use of the space and a much clearer identity for it,” she says. “At the moment, nobody coming to Manchester would say: ‘Oh, we must go and get a selfie in front of whatever in Piccadilly Gardens’. We can change that.”

Other notable city squares

Times Square, New York: In 2017, a six-year overhaul of this Big Apple landmark was completed, turning the once-congested tourist trap into a people-friendly piazza. The famous screens remain but pedestrians now have twice the space they used to. Architects Snøhetta installed five different benches throughout the space, each encouraging a range of sitting postures. Critics said an amphitheatre in the middle of the road would encourage vagrancy and prostitution but their fears were unfounded and Times Square has become a vastly more welcoming place.

Bradford City Park: Considered one of the UK’s most successful public realm revamps, this large public square in front of the Grade I-listed City Hall has become truly beloved of Bradfordians. In the summer, families picnic by the Mirror pool, while children splash in the water, darting in and out of more than 100 fountains, the largest of which, “the Bradford Blast”, rises to 30 metres. Plumbing problems meant the pool ran dry in 2019, proving the importance of a decent maintenance budget.

Alexanderplatz, Berlin: A vast concrete piazza in the heart of former East Berlin dominated by an invincible branch of C&A and the futuristic Fernsehturm (TV tower), Alexanderplatz has been under construction pretty much since reunification. In 1993, the architect Hans Kollhoff won a competition to redesign the square as part of an American-style city centre, but the 10 high-rise buildings in his plan have never materialised and the perennially broke city senate has never found a way to make the cold grey space more welcoming.