A field of waste fills in the gully that has formed between houses on either side in Dar es Salaam, Tanzania. Declan Murray, CC BY-NC-NDI was standing with a waste management supervisor – let’s call him David – at the back of a major fruit and vegetable market in Dar es Salaam, the biggest city in Tanzania. David and I watched as his team raked the market’s waste from a holding bay into the back of a big, yellow tipper truck. “We’re not taking this to Pugu,” David said. “We’re taking this to an illegal site”.Pugu is Dar es Salaam’s only official landfill site. All of the rotten produce, peel, leaves, water bottles, soft plastic and cardboard being loaded into the truck should have been sent there. But Pugu is a two-hour drive away. Fuel costs are expensive and there will probably be a queue of trucks waiting to dump through the site’s single entrance. People also have to pay to dump waste at Pugu. By going to an illegal site, David can save time and money.“No photos,” David said as we neared the illegal site. I put my phone away. We drove down a steep, compressed sand track riven with dried-up channels. Ahead of us, the ground levelled out into a field of many colours; a field of waste. Read more: The world’s waste mountain is rising at an alarming rate I could make out the outlines of popular white plastic milk packets and blue plastic pouches used to package snacks around the city. These were tangled up with old clothes and used nappies. On the far side, the land rose steeply again, populated with houses overlooking the site.While the team dumped the waste from the market, I introduced myself to some locals sat watching nearby. They were at pains to tell me that this was not a valley. It was a gully, they said. There is no river here. Instead, they told me that heavy rain had caused the land to give way and several houses to collapse. In order to stem the erosion they had asked local leaders to bring waste to fill in the gully, to literally fill in the land, and so protect the remaining houses from collapse.In my 2025 study, I defined this practice as “literal landfilling”. It’s apparently widespread and longstanding in the city, yet it has been curiously missing from official and academic discussions of the waste management system in the city. Until now. A tipper truck gets filled up at the market in Dar es Salaam. Declan Murray, CC BY-NC-ND A waste win?Between 2022 and 2024, I spent nine months studying the waste management system in Dar es Salaam as part of a wider research programme on plastic waste in developing countries. That residents welcomed the waste of contractors like David made the literal landfill seem like a win-win-win for contractors; local authorities and residents. Markets, streets and neighbourhoods are cleared of waste, contractor profits are maintained and no more residents lose their homes. But at what cost?Colleagues of mine found that pathogens like cholera and E. coli can thrive on plastic surfaces for three to four weeks. Plastic waste might even be driving the emergence of new diseases. I asked some of the local residents whether they were worried about the health consequences of living right next to this open landfill site. Most conceded they get ill but this was a minor inconvenience relative to the possibility of losing the concrete home they have built.Rather than being a happy alignment of interests, my research shows that literal landfilling is a trade-off between short-term, visible economic gain and longer-term, unknowable losses to human and environmental health.In 2023, the World Bank launched the Dar es Salaam Metropolitan Development Project (DMDP), a US$438 million (£330 million) initiative to improve urban services in the city. Joining a long history of initiatives and plans to solve the city’s waste management problems, the DMDP hopes to modernise Pugu to improve access and reduce waiting times. It also promises the introduction of transfer stations around the city where contractors can deposit waste for sorting and then return quicker to collection than having to drive out to Pugu. If realised, these plans could resolve the supply side of the literal landfill equation – contractors will no longer be incentivised to dispose of waste in gullies. However, the DMDP makes no mention of gully erosion in the city nor are there any other schemes to address it. Until the literal landfill is recognised in official and academic discussions of waste management in Dar es Salaam, residents will still look to protect their assets unfortunately at a cost to their health. The demand for waste will remain.Declan Murray does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.