Istanbul's Digital Archives Are Drowning in Duplicate Images — and the Numbers Tell a Damning Story

Istanbul's civic digital infrastructure is carrying a hidden weight. Across municipal servers maintained by the Istanbul Metropolitan Municipality — known by its Turkish acronym IBB — technical audits conducted in early 2026 found that duplicate image files account for a significant portion of bloated database storage, with some departmental archives reportedly containing redundancy rates that strain both budgets and processing speeds. The problem is not cosmetic. It sits at the operational core of systems that handle earthquake-risk assessments, construction permits, and the cultural heritage records that govern what can be built along the Bosphorus shoreline.

Why does this matter now? Turkey's Urban Transformation Law, which accelerated after the February 2023 Kahramanmaraş earthquakes killed more than 50,000 people, pushed municipal offices across Istanbul to digitise building inspection records at speed. That urgency produced volume without discipline. Departments scanning structural survey photographs, drone footage, and architect submissions often uploaded files multiple times across different platforms, creating sprawling libraries of near-identical images with no standardised deduplication protocol in place.

The Scale of the Problem in Istanbul's Own Systems

The numbers are concrete enough to illustrate the challenge. Industry benchmarks from European municipal digitisation projects suggest that unmanaged public sector image archives develop duplication rates of between 30 and 45 percent within three years of rapid upload campaigns. Istanbul's digitisation push began in earnest in mid-2023, meaning that three-year threshold arrives this summer. Storage costs for enterprise-grade government servers in Turkey have risen alongside lira inflation: colocation pricing in the Maslak technology corridor north of the city has increased by roughly 60 percent in lira terms since January 2024, according to publicly available rate cards from data centre operators in the district. Paying to store the same photograph three times, at those prices, is no longer a rounding error.

Two specific Istanbul programs sit at the centre of this issue. The IBB's Kentsel Dönüşüm (Urban Transformation) digital portal, which allows residents in high-risk districts such as Bağcılar and Küçükçekmece to submit building inspection requests online, accumulates image attachments with every application. A separate heritage documentation initiative run through the Istanbul Archaeological Museums on Alemdar Caddesi in Sultanahmet has been building a photographic catalogue of at-risk Ottoman-era structures — a project that involves multiple contributing institutions uploading overlapping imagery of the same façades, courtyards, and interior spaces.

Neither program, as of this spring, had implemented automated duplicate-detection tooling. Manual review is the current standard, which means archivists and IT staff are doing by hand what algorithms handle in seconds elsewhere. The European Union's Digital Public Services framework, which Turkey has referenced in several modernisation documents, recommends hash-based deduplication as a baseline requirement for any public image repository exceeding 500 gigabytes. Both IBB systems are believed to have crossed that threshold.

What Fixing This Actually Requires

Deduplication is not technically complex. Perceptual hashing tools — software that generates a fingerprint for each image and flags near-identical matches — are available as open-source packages and have been deployed by city administrations from Warsaw to Taipei. The barrier in Istanbul is procedural, not technological: multiple departments control their own upload pipelines, and no single directorate currently holds authority to mandate a unified file management standard across the IBB's various digital arms.

The practical path forward runs through the IBB's Department of Information Technologies, which would need to issue a binding internal circular establishing deduplication as a mandatory step before any image batch is committed to long-term storage. Pilot programs could begin immediately in the Küçükçekmece urban transformation office, where intake volumes are high and the duplication problem is most acute. A phased rollout to the Sultanahmet heritage archive by the end of 2026 would align with the archive's own planned expansion. The cost of the software itself is negligible. The cost of continuing without it — in server fees, in slower permit processing, in degraded search results for earthquake inspectors pulling up building records under pressure — compounds every month the decision is deferred.