Istanbul is one of the world's biggest cities, growing larger still every year. Its rapid expansion is putting enormous stress on its water supplies.

Jodie Harburt often talks about the buzzard. In the wetlands of Şile, the town she lives in – absorbed many years ago into greater Istanbul – Harburt used to see a buzzard alight on the marshes beside the river, a small predatory wonder among the rich variety of birds and bugs and wildlife that called the river home.

The buzzard left, like an omen, when the municipality began to line the river with concrete.

"This area is supposed to be spongy, because that's where the water is supposed to stay. It's a huge water depot," says Harburt. "If you want to avoid drought situations, you have to keep the water in the soil, and you can't do that if you've lined the whole river with concrete."

The problems of one small river in Şile is a ripple out from the large problem that threatens to splash down on Istanbul: what happens if the city runs out of water?

In January 2021, the residents of Istanbul slowly, and then quickly, became inundated with ominous headlines: Istanbul could run out of water in 45 days. With reservoirs at shocking lows and little forthcoming winter rain, it was within the realm of possibility that a city of more than 15 million people might soon have no drinking water. Under the instruction of the Diyanet, Turkey's Directorate of Religious Affairs, Friday services at Istanbul's mosques included prayers for rain and water.

It wasn't the first time this has happened. Similar headlines bubble up in Istanbul's news outlets every few years. For four days in 2014, the Kadikoy neighbourhood of Istanbul had no water. At first, it was an inconvenience. In a city as large as Istanbul, water cuts occasionally happen, and residents grumble but get on and wait for the water to come back. But as the water cut extended to two days, and then three, the neighbourhood began to smell and people looked more and more frantic. By day four, there were full-blown protests as people demanded that the local government restore their water.

Now, the warning bells are ringing again. As recently as 4 October 2024, the reservoir levels were very low, at only 37.4% capacity. In December 2023, Agriculture and Forestry Minister İbrahim Yumaklı announced that Turkey was at risk of experiencing extreme water scarcity by 2030, and that much of the population might feel the effect of water shortages in the next six years.

Kucukcekmece Lake, an important source of water in Istanbul, is at risk of becoming polluted and running dry. Drought is at the doorstep. Day Zero, when the water runs out, is a slow-arriving disaster that is an easy one to ignore – until it arrives.

"Istanbul is already facing significant water scarcity, and we're approaching ecological limits," says Akgün İlhan, a lecturer who specialises in urban water management and its intersection with climate change at Boğaziçi University. "We need to face this reality, or we can continue to ignore it and face the consequences."

Istanbul is a city of water, hemmed in by it on all sides: the Black Sea to the north, the Sea of Marmara to the south, and the Bosphorus Strait bisecting the centre of the city itself – all salt water bodies, with no river to provide freshwater. As its status as a city of local and global importance has grown, the city has stretched out, swallowed its suburbs, and become very, very thirsty.

Always a major city, Istanbul is now a megacity, with its population ballooning in the second half of the 20th Century. In the 1950's, Istanbul had a million residents; by the 1980s, there were five million. Now, there are roughly 17 million. As the population rises, so does the demand for water; as residential areas develop on Istanbul's water basins, less water is available within the city itself.

In reaction, İSKİ, the city's water authority, has built dam infrastructure designed to bring water from villages hundreds of kilometres outside of the city into Istanbul. But when this infrastructure drains the water reservoir of these villages and damages agriculture, the residents........

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