İSKİ, a subsidiary of the Istanbul Metropolitan Municipality (İBB), supplied a total of 1 billion 117 million cubic meters of water to the city in 2023. Of this amount, 841 million 959 thousand cubic meters were sourced from regulators, while 275 million 104 thousand cubic meters came from dams.
A total of 737 million 938 thousand cubic meters of water were consumed on the European Side, and 440 million 532 thousand cubic meters of water were transferred from the Anatolian Side to meet the demand. The day with the highest water consumption was July 27, 2023, when 3.5 million cubic meters of water were used — marking it as the day with the highest consumption in history.
In 2022, İSKİ served 6,819,930 subscribers; this number increased to 6,891,231 in 2023.
Throughout the year, 737,938,674 cubic meters of water were used on the European Side, and 379,125,442 cubic meters on the Anatolian Side. The European Side accounted for 66.06% of total water consumption, while the Anatolian Side represented 33.94%. A total of 440,532,935 cubic meters of water were transferred from Asia to Europe.
In 2022, Istanbul consumed 1,103,672,069 cubic meters of water, while 2023 became the year with the highest water consumption in history, reaching a total of 1,117,064,116 cubic meters. The average daily consumption in 2023 was 3,060,450 cubic meters.
July 27, 2023, went down as the day with the highest water consumption ever recorded, with 3,568,056 cubic meters used. The lowest daily consumption was recorded on April 23, 2023, at 2,524,736 cubic meters.
Istanbul experienced a dry year, with dam levels dropping from around 40% after spring to 30% and even 20% later in the year. The lowest reservoir level was measured at 16.18% on November 11, 2023, while the highest level was recorded on December 31, 2023, at 52.11%.