How London's Planning System Quietly Broke Its Own Image Archive — And Why It's Only Now Being Fixed

London's planning authorities are in the middle of a long-overdue audit of their digital property and heritage image records, after years of database consolidation work exposed a sprawling problem: thousands of duplicate photographs, architectural drawings and survey scans sitting simultaneously across the Greater London Authority's planning portal, the Historic England Archive and individual borough systems. The duplication is not cosmetic. It has delayed planning decisions, confused heritage assessments and, in at least a handful of documented cases reviewed by The Daily London, led to contradictory information appearing on public-facing applications.

The reason this matters now is timing. Keir Starmer's government has made planning reform the centrepiece of its domestic agenda, pushing local authorities to accelerate housing approvals and streamline the consenting process. The Planning and Infrastructure Bill, currently working through Parliament, explicitly requires councils to digitise and standardise records. For London, that legislative pressure has a spotlight effect — it forces the GLA and its 33 borough councils to confront digital housekeeping that has been deferred since at least 2015, when the first major wave of scanning projects began.

How the Duplication Happened

The roots of the problem run back to the early 2010s. The London Legacy Development Corporation, set up in 2012 to manage the post-Olympics transformation of Stratford and the Lower Lea Valley, digitised tens of thousands of images of the site before and during construction. Those files were uploaded to multiple systems without a unified naming convention. The same photograph of the Aquatics Centre under construction might exist as three separate entries, each tagged differently by different officers using different metadata standards.

That was not unique to the Legacy Corporation. When Southwark Council launched its own digitisation drive around 2016 — covering the Bermondsey and Elephant and Castle regeneration zones — images were exported from a legacy database, processed by a third-party contractor and re-imported into a newer system. The contractor's work and the council's original files were never reconciled. Tower Hamlets faced a similar issue after its 2022 boundary review prompted a data migration that duplicated records tied to Canary Wharf planning applications dating back to the late 1990s.

Historic England's London collections, held partly at its offices near Waterloo and accessible through the National Heritage List for England, have their own duplication layer. When local surveys conducted by borough conservation officers are submitted to the national body, they are sometimes scanned independently by Historic England staff who are unaware that a digital copy already exists. The result is an archive where the same Victorian terrace in Islington or the same warehouse facade in Bermondsey Street can appear four or five times under different reference numbers.

The Scale of the Problem — and the Fix

Exact figures for the total volume of duplicated records across all London systems are not publicly available in a single published source, but a 2024 report by the Planning Advisory Service — a body funded by the Ministry of Housing, Communities and Local Government — identified image duplication as one of the three most common data quality failures in local planning portals across England, alongside incomplete addresses and missing decision dates. That report covered a sample of 47 local authorities, 14 of which were London boroughs.

The GLA's digital planning team began a deduplication programme in early 2025, using automated hash-matching software to flag identical or near-identical image files. The programme is ongoing. Camden Council has separately contracted a digital records firm to audit its Conservation Area Appraisal archive, work that started in January 2026 and is expected to run until at least the end of the year. Lambeth is understood to be at an earlier scoping stage.

For anyone submitting a planning application in London right now, the practical advice is straightforward: do not assume that a heritage image retrieved from a public portal is the authoritative or most current version. Cross-reference against Historic England's directly maintained archive and, where possible, contact the relevant borough conservation officer before citing photographic evidence in support documents. The systems are being cleaned up, but that work is live, ongoing and far from finished.