Coventry's Digital Archives Are Full of Duplicate Images — And It's Costing More Than You'd Think

Thousands of duplicate images are clogging Coventry City Council's digital infrastructure, inflating storage costs and slowing public access to records ranging from planning applications to the Herbert Art Gallery and Museum's digitised collection. The problem, long treated as a housekeeping irritant, has emerged as a measurable drain on public resources — and local institutions are now being pushed to act.

The issue matters now because the council is mid-way through a £2.3 million digital transformation programme launched in March 2025, intended to consolidate legacy systems and migrate public-facing services onto a single integrated platform by the end of 2027. Data auditors brought in as part of that programme identified image duplication as one of the top three sources of unnecessary storage expenditure across council departments. Redundant files — identical or near-identical image files stored multiple times across different servers — are not just a tidiness problem. At current commercial cloud-storage rates, every terabyte of avoidable data carries a recurring annual cost, and Coventry's audit reportedly flagged hundreds of gigabytes of duplicate image content in planning and heritage systems alone.

What the Numbers Actually Show

Across the council's planning portal — which serves residents submitting and tracking applications across areas including Earlsdon, Foleshill and the city centre — internal assessments identified that roughly 30 to 40 percent of uploaded image files in active case records were duplicates, typically generated when applicants resubmitted documents or officers re-uploaded supporting photos during case reviews. That level of redundancy is consistent with patterns identified in digital asset audits conducted by local authorities across the English Midlands in recent years, where average duplication rates in public-sector image repositories have been measured between 25 and 45 percent of total file volume.

The Herbert Art Gallery and Museum on Jordan Well, which holds more than 250,000 objects in its physical collection and has been digitising records since the early 2010s, faces a related challenge. The museum's digital asset management system contains tens of thousands of image records, and staff have identified significant numbers of near-duplicate files created when older cataloguing software failed to flag previously uploaded versions. The Coventry Cultural Partnership, which coordinates digital access across the Herbert, Coventry Transport Museum on Millennium Place, and several archive collections, has flagged the duplication backlog as a priority for the 2026-27 financial year.

Storage alone is not the only cost. Staff time spent manually reviewing, tagging and resolving duplicate records represents a hidden labour overhead. A 2024 survey by the Local Government Association found that digital records management consumed an average of 1.8 full-time-equivalent staff hours per week in mid-sized English councils solely on file deduplication and quality checks — a figure that rises sharply when image-heavy departments like planning and heritage are included in the count.

What Comes Next for Coventry

The council's digital transformation programme is piloting automated deduplication software across two council departments this autumn, with a view to rolling the tooling out to the planning portal and cultural heritage databases by spring 2027. The software uses perceptual hashing — a technique that identifies visually similar images even when file names or metadata differ — to flag candidates for removal before a human reviewer makes a final call. Early results from a pilot in Birmingham City Council's planning division, which completed a similar exercise in 2024, suggested storage savings of around 18 percent on image-heavy repositories after a single deduplication pass.

For residents and businesses using Coventry's planning portal — accessible via the council's main website and used by thousands of applicants each year across the CV1 to CV6 postcode areas — the practical upshot should be faster load times and more reliable document retrieval. Heritage researchers accessing the Herbert's online catalogue, which has seen steady growth in remote access requests since pandemic-era gallery closures in 2020, may also find records easier to navigate once duplicate entries are resolved and metadata is standardised.

The council has indicated that progress against the deduplication targets will be reported as part of its quarterly digital transformation updates to the scrutiny board, with the next session scheduled for September 2026.