Zurich's Digital Archives Are Full of Duplicate Images — and Experts Say the Cost of Ignoring It Is Rising

Zurich has an image problem — literally. Across municipal databases, university repositories, and government digital archives, duplicate photographs and scanned documents have quietly accumulated into a storage burden that technology specialists and cantonal officials are no longer willing to dismiss as a housekeeping nuisance. The issue has moved up the agenda this summer as several institutions prepare budget submissions for 2027, forcing a frank conversation about what it actually costs to leave redundant data untouched.

The timing matters for practical reasons. The Canton of Zurich is midway through a multi-year digitalisation programme covering civil registry files, planning records, and historical photographic collections held at the Staatsarchiv on Winterthurerstrasse. At the same time, ETH Zurich's research data infrastructure — which supports image-heavy disciplines from materials science to urban planning — has been scaling up following the university's sustained position near the top of global rankings. Both institutions are reaching a point where unmanaged duplication is no longer a theoretical inefficiency; it is a measurable budget line.

What the Specialists Are Saying

Technology and records-management professionals working in the Swiss public sector describe duplicate-image accumulation as a structural consequence of how large organisations digitised their holdings quickly, without enforcing deduplication protocols at the point of upload. The problem is compounded when multiple departments independently scan the same source material — a pattern that archivists say was common during pandemic-era remote-working adaptations in 2020 and 2021, when coordination between teams at different sites broke down.

Industry guidance from the Swiss Federal Archives, which sets interoperability standards for cantonal institutions, recommends hash-based deduplication tools as a baseline measure. These tools generate a unique digital fingerprint for each image file; if two fingerprints match, one copy is flagged for removal or consolidation. The approach is well-established in private-sector data management, but public-sector adoption in Switzerland has lagged, partly because procurement rules and legacy system constraints slow technology rollouts. Specialists in the field point to the City of Geneva's 2023 archive modernisation project as a reference case that Zurich administrators have studied, though Zurich's holdings are considerably larger.

Storage costs in enterprise-grade Swiss data centres currently run at roughly CHF 0.02 to CHF 0.05 per gigabyte per month for cold archive tiers, according to published rate cards from domestic providers. For an institution holding tens of terabytes of image data — a realistic figure for a large research university or a cantonal archive — duplicates inflating storage by even 15 to 20 percent translate into tens of thousands of francs annually in avoidable expenditure. That figure rises sharply when factoring in backup cycles, which multiply storage consumption further.

Local Institutions Weighing Their Options

At ETH Zurich's main campus on Rämistrasse, the university's scientific IT department has been piloting automated deduplication workflows within select research group repositories since early 2026, according to information published in the institution's internal IT newsletter. The Zentralbibliothek Zürich, which holds one of the largest photographic collections in the German-speaking world and is based on Zähringerplatz, is separately assessing whether its digitisation pipeline for historical glass-plate negatives needs a deduplication checkpoint before files are committed to long-term storage.

Officials at the Stadtarchiv Zürich, located on Neumarkt, have indicated in published planning documents that a data-quality review — encompassing duplicate detection alongside metadata standardisation — is scheduled as part of the archive's rolling five-year development plan. No completion date has been set publicly for that review.

For organisations and businesses outside the public sector that are managing their own image libraries — a category that includes Zurich's substantial pharmaceutical and financial services industries, both of which maintain extensive document archives — specialists recommend auditing repositories before the end of the calendar year, when IT budget cycles typically close. Free and commercial deduplication tools are available, and the Federal Data Protection and Information Commissioner's office has published guidance on data minimisation principles that applies directly to redundant-file management. The practical first step, according to records-management professionals, is establishing exactly how large the duplicate footprint is before committing to any particular technical solution.