Istanbul Reservoir Levels Drop Below 60% Amid Heat Wave

On July 28‑29 2026 the Istanbul Water and Sewerage Administration (İSKİ) reported a rapid decline in the city’s reservoir water levels as soaring temperatures and low rainfall intensified water consumption. By July 28 the average fill rate of Istanbul’s ten reservoirs fell below 60%, with Terkos at 46.41% and Ömerli at 79.15%, while Elmali remained relatively high at 88.37%.

The next day, July 29, the average had slipped further to 55.49%. Elmali stayed the fullest at 87.71%, whereas Pabuçdere recorded the lowest level at 25.19%. Other reservoirs showed varied rates: Alibey 54.97%, Büyükçekmece 39.29%, Darlık 73.2%, Istrancalar 31.31%, Kazandere 29.76%, Sazlıdere 32.41% and Terkos 46.08%. İSKİ warned that the continued heat, rising humidity and lack of rain could threaten Istanbul’s water supply if the trend persists.