Istanbul's Duplicate Image Problem: How the City Stacks Up Against Cairo, Berlin and Seoul

Istanbul's municipal digital infrastructure is carrying a hidden weight. Across the servers maintained by the Istanbul Metropolitan Municipality — known by its Turkish acronym IBB — technical staff have been grappling for the better part of two years with a problem common to fast-growing city administrations: duplicate images clogging planning databases, heritage documentation archives, and the public-facing urban portal at ibb.istanbul. The redundancy is not merely an aesthetic irritant. Storage costs, retrieval failures, and data integrity gaps during disaster-risk assessments have turned what sounds like a housekeeping issue into a material operational problem.

The timing matters. Istanbul sits on active fault lines, and since the February 2023 Kahramanmaraş earthquakes killed more than 50,000 people across southern Turkey, municipal authorities have accelerated the digitisation of structural survey records across the city's 39 districts. Districts like Kadıköy, Fatih, and Avcılar — where seismic vulnerability mapping is most urgent — have seen tens of thousands of building facade photographs, aerial drone captures, and satellite-derived images ingested into IBB's urban resilience platform. Without systematic deduplication, the same damaged wall can appear 40 times in a dataset, distorting risk scores and slowing engineer review cycles.

What Istanbul Is Doing — And What It Has Not Yet Done

IBB's Digital Transformation Directorate launched a pilot deduplication project in the first quarter of 2025, targeting the Bosphorus coastline documentation library maintained by the Istanbul Planning Agency, known as İPA. The coastline archive — used in ongoing disputes over Bosphorus development rights — reportedly contained image duplication rates that technical reviewers estimated had inflated storage consumption significantly, though IBB has not published official figures. The pilot applied perceptual hashing algorithms, a technique that identifies visually near-identical images even when file names or metadata differ.

That pilot remains limited to İPA's coastal holdings. The broader IBB image estate, which includes records from the Istanbul Metropolitan Police coordination system, the tourism-facing digital catalogue of sites like the Sultanahmet Archaeological Park and the Grand Bazaar district, and the disaster preparedness unit's field survey database, has not yet been brought under a unified deduplication regime. Staff at the Beyoğlu district planning office, which manages one of the city's densest heritage documentation loads, are still operating largely on manual review protocols as of mid-2026.

Berlin, Cairo, and Seoul Set the Benchmark

Other cities with comparable archival challenges have moved faster. Berlin's Senate Department for Urban Development completed a citywide image deduplication overhaul in 2024, consolidating records from 12 district administrations onto a single federated platform with automated duplicate flagging. The project, tendered publicly, cost approximately €4.2 million and reduced active storage load by 34 percent according to the Senate's published procurement records.

Cairo's Greater Cairo Region development authority partnered with the United Nations Human Settlements Programme in 2023 to apply similar deduplication tooling to informal settlement documentation in areas like Ain Shams and Manshiyat Naser — archives that had ballooned during rapid drone-survey campaigns. Seoul, whose Smart City Data Hub went live in its current form in late 2022, embedded real-time deduplication at the point of image ingestion, meaning duplicates are rejected before they enter the archive rather than cleaned up retroactively. That upstream approach is now considered best practice by urban data specialists.

Istanbul's position is not hopeless. The IBB Digital Transformation Directorate has scheduled a procurement notice for a citywide image governance platform for the third quarter of 2026, according to the municipality's published tender pipeline on the ekap.gov.tr public procurement portal. If that timeline holds, contract award could come before the end of the year, with implementation running through 2027. For the Syrian refugee community concentrated in districts like Bağcılar and Esenyurt — whose housing documentation often passes through IBB's social affairs image databases — a cleaner, faster-retrieval system would have practical consequences beyond bureaucratic efficiency. Faster document processing means faster access to municipal services. That is the argument IBB's own digital team has been making internally to secure budget approval. Whether the tender attracts competitive bids, and whether the winning solution matches Seoul's upstream model or Berlin's retrospective clean-up approach, will determine how quickly Istanbul closes the gap.