ISTANBUL, TURKEY
Vulnerability map
Istanbul is a city of invaluable cultural heritage, and yet significant portions of it have repeatedly been destroyed. Its location near the North Anatolian fault line has resulted in a long history of earthquakes, recorded as far back as 358. The dome of the Hagia Sophia partially collapsed in 553, 557, 989, and 1436 due to earthquakes. While this particular building has since been largely stabilized, other parts of the city have continued to experience repeated damage from earthquakes. Istanbul engineers expect a 7+ quake in the coming years and have been working to assess the city’s vulnerability to this event. Istanbul’s seismic culture is one of awareness and inquiry, but economics, political upheaval, and the sheer scale of the problem make any action challenging.
Dr. Eser Cakti of Bogazici University describes the vulnerability in terms of direct and indirect losses. The direct losses of building damage and lives lost after an earthquake are catastrophic enough, but the indirect losses of businesses, tourism, and productivity can cascade out for years on a national scale. She states:
“Earthquake vulnerability and loss is a very broad problem, and Istanbul, I would say, is vulnerable in all these clusters of issues.”
Like Seattle, Istanbul has many masonry buildings. Unlike Seattle, these structures span a phenomenal period of time, some well over a thousand years old. Some of these buildings are monumental—mosques or other cultural centers of internationally recognized significance. Istanbul’s monumental structures receive resources and careful oversight to make sure the retrofitting process is true to the architectural character of the building. If Japan excels in technological seismic solutions, Istanbul succeeds in preserving historic character. However, buildings that are not recognized as monumental do not receive the same treatment, and are gradually disappearing, while also posing public safety risks.
Istanbul’s greatest vulnerability is the sheer number and density of buildings that are from before current seismic standards. Approximately sixty to seventy percent of the 1.2 million buildings in Istanbul fall into this category.
