Istanbul's Duplicate Image Crisis: The Key Decisions That Will Shape the City's Visual Archive

Istanbul's municipal digital archive holds a problem that has been quietly growing for years: tens of thousands of duplicate photographs, scanned documents and heritage imagery clogging the servers of public institutions across the city, from the Istanbul Metropolitan Municipality's records offices in Saraçhane to the digitisation labs operated by the Istanbul Archaeological Museums near Sultanahmet. Now, with storage costs rising alongside Turkey's persistent inflation and a coordinated push to modernise municipal data infrastructure before the end of 2026, officials must decide which copies survive — and which vanish.

The timing matters. Istanbul's broader digital infrastructure overhaul, partly tied to the municipality's Smart City Action Plan first adopted in 2023, has accelerated since the Kahramanmaraş earthquakes exposed catastrophic gaps in municipal record-keeping across Turkey. Institutions that once treated digital duplication as a minor housekeeping issue now understand that redundant, poorly catalogued image files can mask missing originals. When a building collapses or a neighbourhood floods, the right photograph — not the fourteenth copy of the same scan — can be the difference between a successful insurance claim and a dispute that drags on for years in civil court.

What the Duplicate Problem Actually Looks Like on the Ground

Walk into the Atatürk Library in Taksim and staff will tell you the cataloguing backlog is real, even if precise figures remain internal. Across the Bosphorus, the Kadıköy Municipality's cultural heritage unit has been attempting since early 2025 to reconcile its photographic holdings with those uploaded centrally by the Istanbul Metropolitan Municipality — a process slowed by incompatible metadata standards and, crucially, by images that appear multiple times under different file names. The Istanbul Archaeological Museums alone digitalised over 1.2 million object photographs as of their last publicly reported milestone, a scale at which duplication rates of even five percent represent tens of thousands of redundant files.

The core technical decision is deduplication methodology: pixel-level matching catches exact copies but misses near-duplicates — the same Galata Tower photograph taken seconds apart, or two scans of the same Ottoman cadastral map at slightly different resolutions. Perceptual hashing algorithms catch more, but they require human review at the margin, and human review costs money. With the Turkish lira's purchasing power still pressured by inflation that ran above 60 percent annually through much of 2024 and into 2025, hiring additional archivists on fixed contracts is not straightforward for any municipality operating under tight budget ceilings set by the Finance Ministry in Ankara.

The Decisions Ahead — and Who Makes Them

Three choices now sit on desks at Saraçhane headquarters. First: does the municipality adopt a centralised deletion protocol, or allow each district unit — Beyoğlu, Fatih, Beşiktaş and the rest — to manage its own image libraries independently? Centralisation is faster and cheaper to audit, but it concentrates decision-making power in ways that are politically sensitive given the ongoing tension between the CHP-run metropolitan municipality and Ankara-aligned district governors in certain neighbourhoods.

Second: what gets backed up before anything is deleted? The Bosphorus waterfront development controversy has already demonstrated how quickly heritage photographs become legal evidence; images of the Karaköy shoreline taken during planning consultations for the Galataport project have appeared in administrative court submissions. Deleting the wrong file now could compromise proceedings that run for years.

Third: does Istanbul follow the model piloted in Barcelona's municipal archive, which in 2023 published a public-facing duplicate-flagging tool allowing researchers and citizens to contest proposed deletions before they happen? That kind of transparency costs time but builds legitimacy — something especially valuable for a municipality that frames itself as a democratic counterweight to central government.

A working group drawn from the municipality's Digital Transformation Directorate and representatives from Istanbul University's information management faculty is expected to present preliminary recommendations by September 2026. What comes out of those meetings will determine not just which images survive, but whether Istanbul enters its next phase of urban development with a coherent visual record — or a patchwork of gaps no algorithm will ever be able to fill.