Istanbul dam occupancy rate at 60.3% amid summer heat

Istanbul's water reserves are showing signs of strain as the city's average dam occupancy rate dropped to 60.3% by July 14, 2026. The Istanbul Water and Sewerage Administration (İSKİ) released the latest figures, indicating a noticeable change in the water levels of the metropolitan area's reservoirs.

The current figures reflect the impact of the ongoing summer heat, which is beginning to affect the city's water supply. İSKİ's real-time automation system provided the data, showing a city-wide average that is a key indicator of water security.

Among the 11 major dams supplying Istanbul, the Ömerli Dam remains the fullest, with an occupancy rate of 85.5%. Other dams with relatively high levels include Elmalı Dam at 90.04% and Darlık Dam at 78.06%. However, several dams are significantly below average, with Terkos Dam at 49.61%, Alibey Dam at 57.14%, and Büyükçekmece Dam at 43.07%.

More critically, Sazlıdere Dam is at 35.98%, Kazandere Dam at 36.93%, and Pabuçdere Dam at 32.82%. The Istrancalar Dam shows the lowest occupancy rate at just 26.51%, highlighting regional disparities in water availability within the supply system.

İSKİ continues to monitor these levels closely, especially as the summer season progresses and demand for water typically increases. The data serves as a crucial reminder of the importance of water conservation amidst varying weather conditions.