Poor urban planning blamed for Istanbul flood damage

ISTANBUL

Experts have attributed extensive flood damage in Türkiye’s largest city to poor urban planning, saying construction along creek beds and concrete surfaces blocking rainwater from reaching the soil have increased the city’s vulnerability.

Former Environment Ministry Undersecretary Mustafa Öztürk said narrowing and covering waterways leaves surrounding buildings exposed to floods. “Rainwater always finds its way,” he said.

He called for wider creek protection zones, mandatory rainwater harvesting, roadside green spaces that collect runoff and rain gardens that let water soak into the soil. He urged checks on flooded buildings’ load-bearing systems, as water corrodes internal steel over time.

Landscape architect Hülya Dinç said 100-meter creek protection strips became 10-meter maintenance strips in 2013. She called for protection zones tailored to each creek’s basin, slope, geology and flood behavior.

“Urban planning decisions cannot be made without considering the integrity of creek systems,” she said.

Istanbul Water and Sewerage Administration (ISKI) 2023 data lists 2,772 creeks totaling 3,919 kilometers. Dinç’s research, based on 2007 maps, found 108 of 168 main creeks outside drinking water basins had lost their natural structure. Only 60 remained intact, while 33 of the 168 lay outside residential areas.

Dinç noted 31 percent of creeks flowing into the Golden Horn are encased in concrete. Waterways such as Ihlamur in Beşiktaş and Fulya in Şişli now lie beneath roads, as does Bayrampaşa beneath Fatih’s Vatan Avenue.

Urbanization accelerated after 1950, spreading to valley floors in the 1980s. Former industrial land along the Cendere creek gave way to housing, offices and malls.