Two or three nights each week, the smell descends. Residents of villages on the rural outskirts of Istanbul don\u2019t know what the smell is, but they have been plagued by it for years: a smell so bad they have to sleep with their windows closed even during hot summer nights. They know the source, too: the huge Silivri municipal waste dump a few miles away that is belching out stinking gases as food and other organic waste rots.<\/p>\n
\u201cThe smell is not subtle. It suffocates you,\u201d said Kemalettin \u00d6zen\u00e7, sitting outside a tea shop in the village of Yol\u00e7at\u0131. \u201cIt\u2019s worse when the air is still: sometimes families linger until midnight out here. Even when you go inside it\u2019s inescapable.\u201d<\/p>\n
These gases are more than a local problem. They include methane, a potent climate-heating gas, pouring out of the site in such vast quantities that the plume is visible from space. Satellite surveillance shows that the Silivri landfill is Turkey\u2019s worst super-emitting waste site<\/a>.<\/p>\n A methane-capture power station near Seymen waste dump, another Istanbul landfill near Silivri, also run by \u0130sta\u00e7. Photograph: Bradley Secker\/The Guardian<\/p>\n In fact, its average emission rate of 7.4 tonnes an hour makes it one of the worst identified anywhere in the world by a team of expert researchers at the University of California (UCLA). The planet-warming impact of this single leak is equivalent to 1.5m gas-guzzling SUVs gunning their engines and there are more super-emitting dumps across Turkey<\/a>. They stretch from \u0130zmir in the west, to Ankara in the centre and Antalya in the south, many with \u201cmind bogglingly large\u201d leaks, the UCLA researchers said.<\/p>\n The revelation that Turkey has some of the world\u2019s worst landfill methane leaks comes at an awkward time: in November, the country will host the next UN global climate summit, Cop31, and has put cutting methane emissions at the top of the action agenda<\/a> it wants all nations to agree on. Turkey\u2019s first lady, Emine Erdo\u011fan, has been a prominent campaigner for zero waste and methane cuts on the global stage \u2013 despite the super-plumes now revealed at home \u2013 and the president, Recep Tayyip Erdo\u011fan, said<\/a> waste management was a priority in a speech he made in June.<\/p>\n Kemalettin \u00d6zen\u00e7 is among those seeking an end to the smell caused by the Silivri landfill site. Photograph: Bradley Secker\/The Guardian\u2018They have the power\u2019<\/p>\n On the ground, the problem has festered for some time. \u00d6zen\u00e7 and a growing crowd of disgruntled people in his town and others around the Silivri landfill have spent years looking for someone to intervene, but the notion of contacting the Istanbul municipality who operate the facility did not cross their minds. Some took to the internet to leave outraged messages about the smell underneath the dump\u2019s listing on Google maps, while \u00d6zen\u00e7 tried to rally people to sign a petition intended for the forestries ministry which oversees several nearby mines.<\/p>\n But in the end, too many were afraid to sign. \u201cThey have the power and can say whatever they want,\u201d he said, in a sweeping reference to the authorities. Turkey\u2019s most notorious maximum security prison looms 30 minutes from Yol\u00e7at\u0131: the mayor of Istanbul, Ekrem \u0130mamo\u011flu, was accused of corruption and detained there in 2025. \u00d6zen\u00e7 and others in the community feared what might happen to them if they were seen to complain too publicly.<\/p>\n Staff from the Istanbul metropolitan municipality\u2019s waste management division, \u0130sta\u00e7, at the site in Silivri appeared surprised when shown satellite images of the massive gas leak emanating from a spot visible from their office windows. Methane, also known as natural or fossil gas, is transparent, and so the plume coming from the site is invisible to the naked eye.<\/p>\n Fatih Arslan of \u0130sta\u00e7 cleared his throat while staring intently at the satellite images presented to him by the Guardian. \u201cWell there\u2019s not much to say,\u201d he said, initially blaming the emissions on areas of the waste site not yet covered with clay after the dumping process. \u201cIt\u2019s inevitable that this is happening \u2026 of course we have to make improvements,\u201d he ventured.<\/p>\n A major plume of methane detected by the Tanager satellite at the Menemen landfill site on 23 December 2025. Photograph: Carbon Mapper<\/p>\n Their priority, he explained, was to cover exposed areas of the dump as quickly as possible and trap the methane produced by the rubbish for use as fuel. An on-site facility extracts 6,000 cubic metres of methane an hour from the landfill to burn for energy: letting methane leak into the atmosphere, he said, is therefore a waste.<\/p>\n For the head of the facility, Ebu Bekir Ikinci, the current situation is actually a vast improvement on the past. He showed newspaper headlines from Istanbul in the 1990s, when the streets were piled high with rubbish and, in 1993, methane trapped at a dump exploded, killing 39 people. A year later, Erdo\u011fan became the mayor of the city with a promise to bring in better waste management.<\/p>\n \u201cThe baseline scenario we use for emissions from waste is what would happen if the waste was not stored at all,\u201d said Arslan, pointing to the deadly scenario from the 1990s. \u201cCompared to that, the emissions now are way better. This is actually very good.\u201d<\/p>\n Engineers monitor energy production at the power plant near the Seymen site. Photograph: Bradley Secker\/The Guardian\u2018Mind-bogglingly large\u2019 rates<\/p>\n Silivri is the largest landfill in Turkey, processing 10,000 tonnes of waste every day. Another waste dump in outer Istanbul, on the other side of the capital in \u015eile<\/a>, is also a source of huge methane leaks, pouring 4 tonnes of methane into the atmosphere every hour, the global heating equivalent of about 800,000 SUVs. The UCLA team used satellite data from the Carbon Mapper portal to identify the 10 highest-emitting landfill sites across Turkey.<\/p>\n \u201cMany of these sites have mind-bogglingly large methane emission rates, even in a global context,\u201d said Cara Horowitz, who leads the UCLA Stop Methane project<\/a>, which carried out the analysis<\/a>, and is executive director at the Emmett Institute on Climate Change and the Environment. \u201cThese are huge leaks, some of the largest single manmade sources of methane emissions in the world,\u201d she added.<\/p>\n Landfills map<\/a><\/p>\n Methane emissions cause a quarter of all global heating and there has been a \u201cscary<\/a>\u201d surge since 2007 that risks triggering catastrophic climate tipping points, scientists have said. However, cutting methane emissions<\/a> is often relatively easy to do and has a rapid impact because the gas is naturally removed from the atmosphere far faster than carbon dioxide. Some experts call cutting methane the climate \u201cemergency brake\u201d.<\/p>\n Turkey says that as the Cop31 host, zero waste and methane reduction are the highest priority<\/a> on its action agenda. Murat Kurum, Turkey\u2019s environment minister and the Cop31 president-designate, wrote to the 196 nations<\/a> due to attend the summit in Antalya, saying: \u201cReducing methane emissions is among the fastest and most effective strategies for slowing near-term temperature rise. The waste sector therefore represents a critical opportunity for delivering immediate climate benefits.\u201d<\/p>\n However, Turkey\u2019s environment ministry declined to comment when contacted by the Guardian about the nation\u2019s methane super-emitters. The Istanbul municipality also declined to answer questions about the methane emissions at Silivri and refused permission to photograph the site.<\/p>\n Reducing emissions from waste disposal has also been described as the \u201cpersonal project<\/a>\u201d of Emine Erdo\u011fan, who is the honorary president of Turkey\u2019s Zero Waste Foundation<\/a> and chair of the UN Advisory Board on Zero Waste<\/a>. While opening a \u201czero waste forum\u201d in June, she noted that some landfills in the world were filled with discarded food while people went hungry, and that food waste causes enormous methane emissions<\/a>. However, Turkey is not among the 159 countries to have signed the Global Methane Pledge<\/a> to achieve a 30% reduction in these emissions by 2030.<\/p>\n \u00d6zen\u00e7 studies a map showing methane pollution over Yol\u00e7at\u0131. Photograph: Bradley Secker\/The GuardianWaste opportunity<\/p>\n Turkey could become a global leader in cutting methane emissions, Horowitz said, if it managed to clean up its many polluting landfill sites. A suite of tried-and-tested solutions exists across the world, ready for adoption, which start with being aware of the leaks. \u201cLandfills are a significant proportion of the top global methane super-emitters, so just making sure we\u2019re accurately understanding the scale of these emissions is an important first step,\u201d she said.<\/p>\n The official record of greenhouse gas emissions submitted to the UN by Turkey acknowledges<\/a> that a major contributor to its emissions from the waste sector \u201cis the uncontrolled release of methane gas from landfills into the atmosphere\u201d, and that such gases are meant to be monitored by the environment ministry<\/a>. However, legislation enacted last August<\/a> \u2013 intended to launch a monitoring mechanism for emissions from select Turkish private interests \u2013 only monitors carbon dioxide emissions, and excludes any facilities \u201cusing biomass\u201d like landfill.<\/p>\n Methane gas coming off landfills can be captured and used as fuel, as at Silivri. However, Dr Tia Scarpelli, waste sector lead at Carbon Mapper, said: \u201cNot all sites that have gas collection are created equal. It does come down to the design and efficiency of the system and day-to day management practices.\u201d Causes of major leaks can include poor maintenance, failure to keep flares alight when burning off excess methane, or collecting only good quality gas and venting the rest.<\/p>\n Though methane can be captured relatively easily, it can still leak from facilities unless they are properly maintained. Photograph: Bradley Secker\/The Guardian<\/p>\n