To negotiate parts of the Cardiff Bay trail by bike on a sunny day is, if not an art, then at least a good test of spatial awareness. Among those on foot and two wheels are families with pushchairs, older people on bikes, kids running, and kids on go-karts and scooters. It’s a picture postcard of the pent-up demand for safe walking and cycling routes away from motor traffic.

While many of us know our towns and cities could look like this – more people-centric and less car-centric – in reality, a lack of political will and consistent funding often puts that out of reach. Here in Wales, a piece of legislation which places people friendly streets is within grasp – if people speak up and tell politicians what to do.

The Active Travel (Wales) Act requires Welsh councils to map their existing walking and cycling routes, and then set about improving and linking them up. The initial mapping stage now complete, people are being asked to say where they want new routes and, crucially, politicians will have a legal obligation to consult anyone who expresses an interest in shaping this process.

It can be as simple as: “I want a safe route to walk, cycle or scoot from my neighbourhood to my child’s school.”

Cycling UK and Sustrans Cymru say it’s key that people get involved, as the act’s success is far from guaranteed, and have created a simple web form to help people show politicians that this matters to them.

As Cycling UK’s chief executive, Paul Tuohy, puts it: “We have this act, which means [politicians] have to respond to public consultation, but like a lot of really good ideas, even if they do there’s no guarantee anything will be done.”

Already there have been signs of unravelling. Many Welsh councils submitted route maps that were a fraction of the real – if flawed – cycle network. I’m told that’s because they don’t meet the new Welsh cycle infrastructure standards. Rather than include all of the network, with the disclaimer some parts weren’t up to scratch, the bad bits were simply left off the map.

Sustrans Cymru’s head of external affairs, Chris Roberts, a former special advisor to the Welsh Government, calls the first mapping stage a “dry run”, the important bit, he says, being what happens next. Every route people suggest to local authorities – so long as it has some utility value, taking people to work, to shops, or schools – should be mapped, and once it’s there, councils have an obligation to keep building cycling and walking routes within that map. The more people propose routes now, the more routes could be built.

People want the Act to work. It started life as a petition from schoolchildren to the Welsh Assembly, before entering Welsh Labour’s party manifesto and becoming law. It seems fitting people get to shape its future.

Government should want it, too. Health is the Welsh Government’s biggest single spend, 48% of its total budget, so there’s an incentive to take more active travel seriously.

It’s no coincidence Assembly member Rebecca Evans, Welsh minister for social services and public health, has the Act among her specific ministerial responsibilities, able, she says, to “devote a significant amount of effort to promoting active travel”.

“I know how excited people are about this Act and the change that it can make if we get it right,” she says.

“This is about supporting local authorities now, to be able to discharge their new duties under the Act fully, so we’re aiming to give local authorities the utmost support that they need in order to do that.”

Although Evans insists Welsh local authorities are on-board, and “the spirit is there”, whether that is the case remains to be seen. A traffic regulation currently bans cycling between 11am-5pm on 11 streets in Newport City Centre.

Nonetheless there’s the legal duty for those still unconvinced about cycling and walking not to drag their feet, both under the Active Travel Act and the Wellbeing of Future Generations (Wales) Act.

One thing that’s not there, though, is the money. There’s just £14m, to be spent among 22 Welsh Local Authorities – a pittance in infrastructure terms, especially when propped up alongside the UK government’s £15bn roads fund. However, as Tuohy points out, the funds are out there.

He says: “Politicians are spending a lot of money on transport, it’s just a question of priorities and percentages.”

“You get sick of spouting Amsterdam and Copenhagen [as examples of cities good with active travel], which are genuinely amazing, but you need political champions to really believe in it, because you can change Cardiff, you can change London, but you have to have the vision.”

He hopes if routes are carefully chosen and well executed, they will make the case for more of the same.

“In terms of pound for pound, boy is it going to pay itself back,” he says. “When you think of the money it takes to build just one mile of motorway, how many miles of cycle routes and walkways you can get for that, it’s just a no brainer, so what on earth are our politicians thinking when they do this stuff? So let’s wake the public up a bit to say: ‘no, we want it to change’. They are our politicians, we vote them in, and we can vote them out.”

And if Wales can do it, we should be asking ourselves, why can’t the rest of the UK?