Barcelona's Duplicate Image Problem: The Numbers Driving a City-Wide Data Cleanup

Barcelona's Ajuntament is sitting on a digital archive problem that has quietly ballooned alongside the city's short-term rental enforcement push. Internal records management specialists working across the city's housing and urban planning departments have identified tens of thousands of duplicate image files — photographs of properties, inspection reports, and permit documentation — stored redundantly across at least three separate municipal data platforms. The scale of the duplication is now measurable, and the figures are uncomfortable.

The timing matters because Mayor Jaume Collboni's administration has staked significant political capital on the short-term rental crackdown. Since the city announced in 2023 that it would not renew any of the roughly 10,000 active tourist apartment licences upon their expiry, enforcement officers have been photographing properties across the Eixample, Gràcia, and Sant Martí districts at a pace the underlying IT infrastructure was never designed to handle. Every inspection generates multiple images. Many of those images are uploaded more than once.

What the Data Actually Shows

Duplicate image files in large municipal archives are not a Barcelona-specific quirk — Amsterdam and Lisbon have faced similar clean-up operations as housing enforcement digitised rapidly after 2020. But the Barcelona case has a particular shape. According to publicly available procurement documents posted on the Perfil del Contractant platform, the city's Àrea de Drets Socials, Justícia Global, Feminismes i LGTBI put out a contract in late 2025 for digital asset management services covering urban inspections. The documentation referenced storage inefficiencies across legacy systems, one of which dates to a 2014 integration of the old Habitatge database.

Specialists in municipal data architecture estimate — though no official city figure has been published — that duplication rates in unmanaged government image repositories typically run between 18 and 35 percent of total stored files. Applied conservatively to a housing enforcement archive that has grown sharply since 2023, the redundant storage costs are not trivial. Cloud and on-premise storage in public-sector environments across the EU ran at roughly €0.02 to €0.05 per gigabyte per month through 2025, according to published European Commission procurement benchmarks. High-resolution inspection photographs average between 3MB and 8MB each. At scale, the arithmetic adds up fast.

The practical consequence is slower case processing. When an inspector in the Poblenou neighbourhood files documentation on a disputed Airbnb-style rental, and that file duplicates imagery already logged by a colleague two weeks earlier, case officers at the Oficina de l'Habitatge on Carrer de Llull must manually reconcile the records before a licence penalty can proceed. Duplicate data does not just waste storage — it introduces legal risk into enforcement actions that landlords' lawyers are already contesting aggressively.

The Clean-Up Operation Now Under Way

The Institut Municipal d'Informàtica, the city body responsible for Barcelona's technology infrastructure, has begun a phased deduplication programme as part of the broader Barcelona Digital City strategy. The first phase targets property-related image archives and is expected to run through the end of 2026. No official completion date for the full project has been published.

Barcelona-based civic technology organisation Localret, which advises Catalan municipalities on digital infrastructure, has been vocal in wider forums about the costs of deferred data hygiene in local government — though it has not commented publicly on the specific Ajuntament project. The problem is not unique to image files: permit PDFs, cadastral maps, and inspection videos face the same redundancy issue.

For residents and landlords with active cases before the housing office, the practical advice is straightforward: when submitting documentation through the city's Seu Electrònica portal, reference all previous submission dates and case numbers in the covering note. This reduces the likelihood that inspectors working from duplicated files will reopen matters already resolved. The city has also published guidance — available at ajuntament.barcelona.cat — asking applicants to avoid re-uploading documents already on record. It is a workaround, not a solution. The real fix is in the server rooms, and Barcelona's data teams know it.