How Zurich's Digital Archives Ended Up Full of the Same Image Twice — and What It Cost

Zurich's public institutions are sitting on a problem that nobody wanted to talk about until the invoices started arriving. Duplicate images — identical or near-identical digital files stored redundantly across servers, archives and content management systems — have accumulated quietly inside city departments, hospitals, universities and cultural bodies over roughly two decades of uncoordinated digitisation. The cost of storing, managing and now auditing that redundant data is prompting a reckoning that administrators at the Stadthaus on Stadthausquai can no longer defer.

The issue sounds mundane. It is not. When every department built its own digital workflow after 2005, nobody agreed on a single taxonomy, a shared image library or a deduplication standard. The result, across institutions from the Zentralbibliothek on Zähringerplatz to the city's sprawling health network under Gesundheitsdirektion, is that identical photographs, scans and graphic assets were ingested, renamed and saved in parallel — sometimes dozens of times. A single aerial photograph of the Limmat river corridor, for instance, might live in the urban planning department's server, the tourism board's CMS, the press office's Dropbox successor and three archived hard drives in the Stadtarchiv on Neumarkt, each copy treated as a distinct asset.

How the Duplication Crisis Took Root

The path to this point runs through several distinct phases. Between roughly 2004 and 2012, Swiss public institutions accelerated their shift to digital-first communications. ETH Zurich, ranked consistently among the world's top ten universities for engineering and natural sciences, built its own sophisticated asset management infrastructure relatively early — but most smaller city bodies did not follow suit. They bought storage as it became cheap and copied files as needed, with no centralised governance body to enforce standards.

The UBS-Credit Suisse merger and the subsequent regulatory scrutiny of Swiss financial data governance — a process still generating compliance costs well into 2026 — sharpened thinking about data hygiene in the banking sector. But that discipline was slower to reach municipal image libraries. The Stadtarchiv estimates it holds records stretching back centuries, and the digitisation push of the 2010s added millions of image files in formats ranging from TIFF to low-resolution JPEG, many catalogued inconsistently.

Zurich's housing shortage — the Wohnungsnot that has pushed average asking rents for a three-room flat in Kreis 4 and Kreis 5 above CHF 2,800 per month in recent listings — has an indirect connection to the data problem. As the city's population grew past 450,000 and departments expanded, IT infrastructure scaled to meet headcount without pausing to audit what was already stored. By the time cloud migration became standard practice after 2018, the duplicates migrated too.

Audits, Costs and the Path to Rationalisation

The direct financial exposure is hard to pin down precisely because departments have not historically shared storage invoices in consolidated form. What is clear is that enterprise cloud storage contracts, typically priced per terabyte per month, make redundant data expensive in a way that local hard drives once obscured. Industry benchmarks for Swiss public-sector cloud contracts suggest per-terabyte annual costs in the range of CHF 200 to CHF 500 depending on redundancy tier — meaning that even a modest 50-terabyte duplication problem across city systems represents a recurring six-figure overhead.

The Zurich Stadtrat has tasked the Departement der Industriellen Betriebe with developing a unified digital asset management framework, with a working group expected to report preliminary findings before the end of the third quarter of 2026. ETH Zurich's chair of information management has been named as an advisory partner in that process. The Zentralbibliothek, which completed its own partial deduplication exercise in 2024, is being cited internally as a model for how institutions can reduce storage load without losing archival integrity.

For individual departments facing their own audits, the practical priority is straightforward: begin with high-volume image sources — press photography archives, event documentation, satellite and aerial imagery — because those categories account for the largest share of redundant storage by file size. Standardising on a single master-file protocol and assigning clear custodianship before the next budget cycle begins in autumn will determine whether Zurich's digital housekeeping bill shrinks or keeps growing.