Paris Confronts Its Duplicate Image Problem: The Key Decisions That Will Shape the City's Visual Future

The numbers are stark. Paris's Direction des Affaires Culturelles, which oversees the city's photographic and archival holdings, has identified a growing backlog of duplicate image files spread across at least three separate municipal databases, a problem that has quietly ballooned since the city began aggressively digitising its built-environment records ahead of the Paris 2024 Olympics. Now, with the Games two years in the past and the legacy-activation phase well underway, administrators face a concrete reckoning: what to do with the redundant visual material, who pays for the cleanup, and which systems ultimately take precedence.

The issue matters now for a specific reason. Grand Paris Express, the €36 billion metro expansion project overseen by Société du Grand Paris, requires high-resolution geo-tagged images of hundreds of surface sites from Saint-Denis to Orly. Engineers and urban planners have flagged that duplicate imagery—some files differing only by timestamp or compression level—is creating data-matching errors in the project's geographic information system. A delay in resolving the problem risks slowing environmental-impact assessments for at least four stations on Line 15 South, where construction phasing decisions are expected before the end of 2026.

Where the Duplication Is Worst—and Who Owns What

The worst affected archives are concentrated in two overlapping domains. First, the city's own Observatoire Photographique du Paysage Parisien, based at the Pavillon de l'Arsenal on Boulevard Morland in the 4th arrondissement, holds tens of thousands of landscape survey images dating back to 2003. Staff there have been quietly deduplicating records since January, but the process is manual and slow. Second, the Paris tourism authority, l'Office du Tourisme et des Congrès de Paris, maintains a separate image library used by hotels, travel platforms and press offices; that library was expanded rapidly between 2023 and 2024 to support Olympics-era promotional campaigns, leaving it riddled with near-duplicate shots of the Seine riverbanks and the Trocadéro esplanade.

The Seine urban regeneration programme adds another layer of complexity. Réaménagement des Berges de la Seine, the multi-year project that transformed the right-bank expressway between the Pont de l'Alma and the Pont d'Iéna into public space, has generated thousands of before-and-after site images commissioned by different contractors at different stages. Many overlap substantially. Legal ownership of those images—contractor copyright versus public-domain status under French law—remains unresolved for an estimated 12,000 files, according to planning documents reviewed by The Daily Paris.

The Decisions That Cannot Be Delayed

Three choices are now on the table, and each carries political as well as technical weight. The first is whether to invest in automated deduplication software. Estimates circulating within the Direction du Numérique de la Ville de Paris suggest a procurement process could cost between €400,000 and €900,000 depending on the vendor and the scope of integration with existing systems. Under current National Assembly budget pressure on municipalities, that is not a trivial line item.

The second decision concerns interoperability. The city must choose whether to migrate its photographic assets onto a single unified platform—potentially hosted by the Bibliothèque nationale de France under an existing framework agreement—or continue managing parallel systems that duplicate not just images but also the administrative overhead of maintaining them. The BnF's Gallica platform already holds millions of digitised items and has the infrastructure; the political question is whether City Hall is willing to cede operational control of contemporary municipal imagery to a national institution.

The third and most urgent call involves Grand Paris Express specifically. Société du Grand Paris has set an internal deadline of October 2026 for resolving the geo-tagged image conflicts affecting Line 15 South station assessments. If the municipal deduplication effort has not produced clean, verified datasets by then, the project's technical teams have indicated they will commission entirely new photographic surveys of the affected sites—an expensive and avoidable duplication of effort in itself.

For residents watching the Grand Paris Express construction sites near Villejuif or Bagneux, this bureaucratic tangle may feel remote. But the practical consequence of delay—slower environmental sign-off, pushed-back construction timelines, higher eventual costs—lands squarely on the suburban commuters the project was designed to serve. The image problem, in short, is not just an archivists' headache. The decisions made at the Pavillon de l'Arsenal and at Grand Paris Express headquarters over the next four months will have consequences measured in years, not pixels.