Delhi's Duplicate Image Problem: How the Capital Stacks Up Against London, Singapore and São Paulo

Delhi's municipal and heritage agencies are sitting on hundreds of thousands of digital asset records — many containing duplicate, mislabelled or near-identical images — and the effort to clean them up is years behind comparable programs in cities such as London, Singapore and São Paulo. That gap, long invisible to the public, is now forcing a reckoning across the Delhi government's digital estate.

The problem matters because India's capital has accelerated its push toward smart-city governance over the past three years. The Delhi government's e-governance portal, which serves residents across all 11 districts, relies on image databases for everything from heritage documentation in Shahjahanabad to infrastructure planning along the Delhi Metro Phase 4 corridor in Janakpuri and Tughlakabad. When those databases contain duplicates — the same photograph filed under two dozen different accession numbers — automated systems misread the records, inflate project cost estimates and make archival searches unreliable.

What Other Cities Have Done

Singapore's National Heritage Board completed a de-duplication exercise across its civic image repositories in 2023, cutting redundant files by roughly 34 percent. London's Lambeth and Southwark councils jointly ran a digital asset audit in 2024 under the UK Government's Local Digital programme, a Treasury-backed initiative. São Paulo's Secretaria Municipal de Urbanismo e Licenciamento began piloting AI-assisted duplicate detection in late 2024 across its land-use planning databases, with phase one results published in April 2025. Each city used a different technical approach, but all three set formal timelines, allocated ring-fenced budgets and published progress reports — steps Delhi has not yet taken in any formal documented policy.

Delhi's closest institutional analogue is the Archaeological Survey of India, which maintains photographic archives for protected monuments including Humayun's Tomb in Nizamuddin East and the Qutb Minar complex in Mehrauli. The ASI has acknowledged in previous annual reports that its digitisation program, launched in 2018, produced large volumes of unverified duplicate entries. The Delhi Urban Heritage Foundation, a non-governmental organisation that works alongside the ASI on documentation projects in Old Delhi's Walled City, has flagged the problem to planning bodies more than once. Neither organisation has publicly released a de-duplication completion target or budget figure as of the date of this article.

The Cost of Inaction in the Capital

The practical consequences are not abstract. The Delhi Development Authority, which is managing land acquisition and design documentation for Metro Phase 4's 65.1-kilometre network, relies on georeferenced image files to validate site surveys. Duplicate or conflicting images in those records can delay clearance decisions by weeks. In a project of Phase 4's scale — the DDA's own published documents cite a capital cost in excess of Rs 24,948 crore — even minor administrative holdups carry financial weight.

The Indian Institute of Technology Delhi's Centre for Urban Science and Engineering, located in Hauz Khas, has published research on digital record redundancy in Indian municipal systems, noting that the cost of retroactive clean-up typically runs three to five times higher than prevention-stage quality control. That finding aligns with what planning consultants in London and Singapore have reported after completing their own audits.

What happens next depends largely on whether Delhi's agencies treat this as a standalone technical task or embed it in a broader data-governance framework. The Aam Aadmi Party government's Smart City Cell, operating out of the Delhi Secretariat at ITO, is understood to be reviewing proposals for a unified digital asset management protocol, though no formal notification has been issued. Residents and heritage workers who use the city's online planning portals — particularly those submitting documentation for properties in conservation zones around Chandni Chowk — would see direct benefits from cleaner image records: faster approvals, fewer rejected submissions and more accurate historical data to draw on. The cities that have moved quickly on this problem did so not because the technology was complex but because someone decided a deadline mattered.