Istanbul, February 18 – The occupancy rates of dams supplying water to Istanbul have surpassed 40%, a significant increase attributed to recent precipitation. This marks a 23.68% rise in water levels over the past two months, providing relief after a period of low reserves.
Rainfall Boosts Dam Levels
According to data from the Istanbul Water and Sewerage Administration (İSKİ), the dam occupancy rate, which had fallen to 17.12% on December 7, 2025, has steadily increased due to consistent rainfall. Since the beginning of the year, 207.36 millimeters of precipitation have fallen in the dam basins.
The last 14 days alone saw a 6.75% increase in dam levels. As of today, February 18, 2026, the overall occupancy rate for dams supplying the city stands at 40.48%.
Individual Dam Levels:
- Ömerli: 56.64%
- Darlık: 58.75%
- Elmalı: 89.46%
- Terkos: 25.84%
- Alibey: 34.23%
- Büyükçekmece: 29.19%
- Sazlıdere: 25.44%
- Istrancalar: 74.42%
- Kazandere: 39.42%
- Pabuçdere: 23.42%
Total Water Storage and Supply
Istanbul’s dams and ponds have a total storage capacity of 868.683 million cubic meters. Currently, the stored water volume is recorded at 351.32 million cubic meters.
In addition to the dams, Istanbul has received 136.38 million cubic meters of water this year from external sources: 94.57 million cubic meters from Melen and 41.81 million cubic meters from Yeşilçay. Yesterday, Istanbul consumed 2.996 million cubic meters of water, with all of it supplied from the Melen and Yeşilçay regulators.
Historical Context and Future Outlook
Despite the recent increase, the current dam occupancy rate of 40.48% for February 18, 2026, is the second lowest for this period in the last decade, according to İSKİ statistics. For comparison, historical rates on February 18 were:
- 2016: 86.74%
- 2017: 85.65%
- 2018: 79.51%
- 2019: 91.59%
- 2020: 61.8%
- 2021: 48.67%
- 2022: 80.25%
- 2023: 33.94%
- 2024: 75.56%
- 2025: 66.01%
While the recent rainfall has provided a much-needed boost, the comparison with previous years highlights the ongoing importance of water conservation and careful management of resources for Istanbul’s growing population.
Source: Anadolu Agency, Istanbul Water and Sewerage Administration (İSKİ)
