Istanbul's Digital Archive Push Hits a Wall: Duplicate Image Problem Slows Municipal Record Overhaul

The Istanbul Metropolitan Municipality's digitisation drive, running since January 2025 under the Dijital İstanbul initiative, ran into a concrete obstacle this week: tens of thousands of duplicate image files embedded in the city's centralised archive servers are blocking the next phase of the project, according to municipal documents reviewed by The Daily Istanbul. The problem surfaced after contractors flagged processing errors during a routine upload batch on June 30.

The timing matters. The municipality had planned to open a public-facing portal — allowing residents, researchers and urban planners to search historical maps, construction permits and neighbourhood survey photographs — by September 1, 2026. That deadline is now under pressure. With roughly 1.4 million scanned files already uploaded to the central repository hosted at the Atatürk Library on Millet Caddesi in Beyazıt, administrators say duplicate entries may account for as many as 15 to 20 percent of the total — a figure that, if accurate, would represent a significant data management failure at the project's midpoint.

How the Duplicates Accumulated

The root cause, according to internal notes circulated among the project's technical teams, traces back to a coordination gap between three separate scanning units operating simultaneously: one based at the Istanbul Metropolitan Municipality's main headquarters in Saraçhane, one at the Atatürk Library itself, and a third contracted to a private firm working through the Fatih district archive depot on Fevzi Paşa Caddesi. All three were scanning overlapping sets of physical records without a shared deduplication protocol in place.

Physical archives in cities like Istanbul are notoriously layered. Decades of administrative reorganisations — including the 2012 merger that folded 16 smaller municipalities into the metropolitan structure — left documents scattered across dozens of storage sites. When scanning began, teams at different locations frequently processed the same photograph or permit document independently, assuming the other site had not yet covered it. The result was a cascade of identical files assigned different metadata tags, making automated deduplication software less effective.

The Dijital İstanbul programme had a stated budget allocation of 47 million Turkish lira for the 2025–2026 fiscal period, a figure cited in the municipality's published budget documents from November 2024. A portion of that — exact figures were not specified in reviewed documents — was earmarked specifically for data quality management. Contractors now say additional resources will be needed to run a full deduplication sweep before the portal launch can proceed.

What Happens Next for the Archive Project

The municipality's technical directorate is expected to present a revised timeline to the city council's culture and digital affairs subcommittee no later than July 14. The most likely short-term fix involves deploying hash-based image matching software to identify pixel-identical files, a process that can run largely automatically but still requires human review for near-duplicate images — photographs taken seconds apart or documents scanned at slightly different resolutions.

For Istanbul residents with a stake in the archive, the practical impact is a delay in access to records that have direct relevance today. Urban researchers at Istanbul Technical University in Maslak have been waiting on construction photographs from the 1950s Adnan Menderes demolitions in Eminönü — images critical to ongoing debates about heritage protection along the Bosphorus waterfront. Historians studying the Syrian refugee community's settlement patterns in districts like Bağcılar and Esenyurt have also flagged the archive as a key primary source for longitudinal demographic work.

The September deadline, while tight before this week's developments, has not been officially abandoned. If the deduplication sweep can be completed by late July, the remaining upload and indexing work could theoretically still fit within the window. The alternative — a phased launch beginning with pre-cleaned record sets — is also on the table, which would allow researchers to access a partial archive while cleaning continues in the background.

Anyone currently using the municipality's interim archival request system can still submit document requests through the e-Belediye portal, where a processing time of up to 15 working days applies. The physical reading room at the Atatürk Library remains open Monday through Friday, 9 a.m. to 5 p.m.