Water consumption in Istanbul at historic peak

Istanbul saw its highest level of water usage to date in 2025. According to data from the Istanbul Water and Sewerage Administration (İSKİ), the total annual water consumption across the city reached 1 billion 173 million 331 thousand 21 cubic meters. This amount corresponds to approximately five times the capacity of the Ömerli Dam, one of Istanbul's largest water sources.

SERVICE PROVIDED TO OVER 7 MILLION SUBSCRIBERS

As of last year, water service was provided to 7 million 6 thousand 823 subscribers in the city. The growing population and increased water usage in daily life were influential in the consumption figures breaking records.

EUROPEAN SIDE RANKS FIRST

The majority of water consumption took place on the European Side. While 767 million 655 thousand 586 cubic meters of water were used on the European Side, consumption on the Anatolian Side was recorded at 405 million 675 thousand 435 cubic meters. Accordingly, 65.43 percent of total usage occurred on the European Side, while 34.57 percent occurred on the Anatolian Side.

DISTRIBUTION OF WATER SOURCES

A significant portion of the water used was supplied from external sources and dams. According to the data, 470 million 214 thousand 817 cubic meters of water were provided from the Melen System, 97 million 300 thousand 839 cubic meters from Yeşilçay, and 456 million 88 thousand 581 cubic meters from dams. Streams in the Istrancalar region and various wells also met the remaining demand.

RECORD IN DAILY CONSUMPTION IN JULY

In 2025, the highest daily water consumption was measured on July 24 at 3 million 750 thousand 829 cubic meters. The lowest daily consumption was 2 million 652 thousand 128 cubic meters on March 31. Throughout the year, Istanbul's average daily water usage was at the level of 3 million 214 thousand 606 cubic meters.

DAM OCCUPANCY AND PRECIPITATION DATA

The occupancy rate in the dams supplying water to Istanbul showed significant fluctuations throughout the year. The lowest occupancy was measured at 17.12 percent on December 7, while the highest rate was recorded at 82.36 percent on April 15. The total amount of precipitation that fell on the dam basins across the city throughout 2025 was 619.95 millimeters.

News Source: 12punto