Kentleşme Baskısı Altında Havza Alanları: İstanbul İncelemesi

Öz

İstanbul, Türkiye’nin en kalabalık şehri olup anomalik biçimde büyüme göstermektedir. Kent nüfusundaki artış, doğal arazi örtüsü, sulak alanlar vb. diğer doğal, ekolojik alanları doğrudan etkilemektedir. Bu etkilerin başlıcalarından biri kentsel havzalar üzerinde olmaktadır. Küresel iklim değişikliği ve doğal kaynakların sürdürülebilirliğinin kentsel planlama gündeminde yer alması, mega kent için su yönetimi ve havza alanlarının önemini artırmaktadır. Bu çalışmada, İstanbul'daki içme suyu havza alanları üzerindeki kentleşme baskısının mevcut durumu analiz edilerek yakın gelecek için bir tahmin yapılmakta ve mevcut arazi kullanım verileri ile mevcut yasal-idari koşullar birlikte incelenmektedir. Elde edilen bulgulara göre İstanbul’daki içme suyu havzaları içerisinde en büyük yapılaşma baskısının, Terkos üzerinde olduğu tespit edilmiştir. Terkos havza alanı mutlak koruma alanında 1291, kısa mesafe koruma alanında 3635 adet yapı bulunmaktadır. Terkos'taki mutlak koruma alanındaki yapı stokunun tüm havza bölgelerindeki mutlak koruma alanındaki yapı stokuna oranı %31,28'dir. Terkos, hem kısa mesafeli hem de mutlak koruma alanı içinde en fazla yapı bulunan havza alanıdır. Mevcut duruma ek olarak, Kanal İstanbul gibi mega projeler ve yapılaşma trendleri, Terkos'taki yapı yoğunluğunun yakın zamanda artacağını göstermektedir. Su ekosistemlerin sürdürülebilirliği su havzalarına bağlıdır. Bu nedenle havzalar için entegre su kaynakları yönetimi planlarına ihtiyaç duyulmaktadır. Su kaynakları üzerinde yetki sahibi kurumlar arasında düzenlemelerin ve denetim mekanizmasının oluşturulması gerektiği tespit edilmiştir.

Anahtar Kelimeler

• Havza Alanları
• Içme Suyu
• Kentleşme Baskısı
• İstanbul

Watershed Areas under Urbanisation Pressure: The Case of Istanbul

Abstract

Istanbul is the most populous city that is growing anomalistically in Turkey. An increase in urban population, natural land cover, wetlands, etc., directly affect other natural and ecological areas. One of the main effects is on urban watersheds. Global climate change and the sustainability of natural resources are included in the urban planning agenda increasing the importance of water management and watershed areas for the megacity. In this study, by analyzing the current situation of the urbanization pressure on the drinking water basin areas in Istanbul, a prediction is made for the near future and current land use data and current legal-administrative conditions are examined together. According to the findings, the highest building pressure among the drinking water basins in Istanbul is on Terkos. There are 1291 buildings in the strict preservation zone of the Terkos watershed area and 3635 buildings in the short-distance preservation area. The ratio of strictly protected area building stock in Terkos, to the strictly protected area building stock in all watershed areas is 31,28%. Terkos is the watershed area with the highest number of buildings in both short-distance and strictly protected areas. In addition to the current situation, mega projects, and construction trends such as Kanal Istanbul, indicate that the building density on Terkos will increase soon. The sustainability of aquatic ecosystems depends on watersheds. Therefore, integrated water resources management plans are needed for basins. It has been determined that arrangements and control mechanisms should be established between the institutions having authority over water resources.

Keywords

• Watershed Areas
• Drinking Water
• Urbanisation Pressure
• Istanbul

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