"It's always frustrated me that we can't compost here - even though I get why. Tower blocks just aren't built for it," said Alexandra, a 42-year-old Tower Hamlets resident, living on the ninth floor. She gestures toward the tall buildings in her neighbourhood. Her frustration is shared by many, where food waste collection from blocks of flats remains a challenge.

Tower Hamlets in east London is England's most densely populated borough, with more than 15,000 people per square kilometre. More than 81% of its residents live in high-rise flats, and 30% of its rubbish is food waste.

For residents like Alexandra, the lack of options is disappointing. "When I first moved here, I looked into food waste disposal, but there weren't many options for people in flats," she says. Unfortunately, her experience reflects a wider problem.

According to the UK waste charity Wrap, nearly a quarter of the UK's food production is wasted each year - that's over 6.4 million tonnes of edible food worth Pound 21 billion, enough to feed the country for nearly three months. Households contribute approximately 60% of this waste, which not only costs money but also fuels climate change.

London authorities have introduced reduction and recycling plans (RRPs) to tackle food waste and increase recycling. These efforts align with the mayor's London-wide strategy to halve food waste by 2030. While these targets are ambitious, their implementation in high-rise boroughs such as Tower Hamlets remains a challenge.

For many residents, food waste is both an environmental issue and a logistical nightmare. "We tried compost bins in our building, but rats and foxes loved them more than we did," laughed Aisha, a resident I interviewed at a community centre in March 2023.

Limited space makes traditional composting methods such as wormeries (small-scale systems where worms break down organic waste into compost) unfeasible. The people I interviewed explained that community-led schemes often struggle due to limited participation in the first place, contamination from improper waste disposal and pest control issues including attracting rats and foxes.

In my work as a sustainability marketing researcher, I'm investigating alternatives and researching how best to maintain sustainable consumer behaviour.

Co-creation - in this case, designing solutions with the residents trying to tackle food waste - is so important, but often overlooked. By talking directly to the people involved, a plan will end up being much more effective because people trust it more and engage with it more willingly.

In 2023, I led a six-month behaviour change research project with East London Garden Society, a community-driven initiative focused on promoting gardening and environmental sustainability in east London. I interviewed 15 Tower Hamlets residents, listened to numerous community meetings and analysed community discussions to uncover the real barriers to food waste reduction.

My findings were clear: residents don't just want tips - they want a voice.

As 64-year-old Maryam put it: "I really appreciate that you're taking a resident-first approach, gathering feedback and understanding experiences. That's how you'll find what truly works."

By placing residents at the centre, we can ensure that solutions are built to last. But co-creation alone is not enough - residents need systematic changes, such as better infrastructure.

A 2024 study shows how technology is reshaping the food system from production to consumption. Apps such as Olio help consumers share surplus food and reduce waste.

Some composting machines or food waste processors are compact enough for household kitchens, requiring no garden. Residents can use the resulting compost to grow small plants on their balconies or add it to their green waste bin - this process is made easier by the reduction in volume.

Larger compost machines can turn organic food waste into nutrient-rich soil in just 24 hours, reducing its volume by up to 80% - while these can handle organic waste from multiple high-rise buildings, they need to be installed in a bigger shared community space.

In Tower Hamlets, where space is limited, compact technology offers a convenient solution. But, as we found in our research, it's not without its challenges.

As Frank, a man who lives on a top-floor flat, explained: "This machine is much quicker than traditional composting, but what about the cost and the electricity it uses?" While smart technologies offer convenience, some Tower Hamlets residents raised concerns about energy consumption and costs - so there is a trade-off between ease and energy efficiency.

Read more: Most food waste happens at home - new research reveals the best ways to reduce it

Surprisingly, composting technology, often seen as the eco-friendly solution, may be worsening the food waste crisis. As a marketing expert, I spoke directly with many consumers at Tower Hamlets.

One told me that composting makes them feel "less guilty" about throwing out food. When composting serves as a licence to waste, it can increase the amount of food that is discarded.

Making composting easy diverts waste from landfills, but that doesn't address root causes including simply buying too much food in the first place. To reduce food waste, technology must promote behavioural change such as better meal planning and waste monitoring. Knowing how much food waste they produce, compared to their neighbours, can encourage people to change their behaviour.

So many cities face the same problems, with densely populated communities living in flats without gardens. Without co-creating practical solutions with residents, achieving waste reduction goals will be tough.

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