Delhi Battles Millions of Duplicate Records in Government Databases

Delhi's municipal and state government databases contain tens of thousands of duplicate photographic records — property documents, ration card images, voter ID photographs and heritage site inventories — spread across at least four separate agencies that do not talk to each other. The problem is not new, but pressure to fix it has sharpened in 2026 as the Aam Aadmi Party government pushes a digitalisation drive ahead of the next civic election cycle, and as the Delhi Metro Rail Corporation prepares to onboard commuters onto a unified smart-card system tied to biometric data under Phase 4 expansion work along the Janakpuri West–RK Ashram corridor.

Why does this matter right now? Duplicate image records create real administrative friction: property title disputes in congested colonies like Shahjahanabad in Old Delhi and Uttam Nagar in the west have been delayed for months when land registry offices pull contradictory photographic evidence stored under different file identifiers in the Delhi Revenue Department's legacy system. Welfare disbursements under the Mukhyamantri Mahila Samman Yojana have reportedly stalled in individual cases because of mismatched beneficiary photographs across the Delhi government's JAM — Jan Dhan, Aadhaar, Mobile — verification pipeline, though the government has not published aggregate data on the scale of disruption.

What Other Cities Have Done

The comparison with Mumbai is instructive. The Brihanmumbai Municipal Corporation completed a deduplication audit of its property photograph database in March 2025, contracting the work to the National Informatics Centre at a cost the BMC placed on public record at roughly ₹4.2 crore. London's Government Digital Service published a cross-departmental image deduplication standard in 2022 that required all borough councils to adopt perceptual hashing — a technique that flags visually similar images without storing additional copies — by January 2024. São Paulo's Prefeitura launched a similar programme through its Secretaria Municipal de Inovação e Tecnologia in late 2023, targeting duplicates inside its urban planning cadastre ahead of a major zoning reform.

Delhi has no equivalent published timeline or contracted programme. The Delhi e-Governance Society, which sits under the Department of Information Technology and operates the state data centre on Laxmi Nagar's Vikas Marg, has circulated internal proposals for a deduplication framework since at least 2023, according to procurement notices visible in the public tender portal. None have resulted in a awarded contract as of July 2026. The society did not respond to a request for comment sent Thursday.

The Delhi Urban Heritage Foundation, a non-profit that maintains a photographic archive of monuments in areas including Mehrauli and Nizamuddin, ran its own internal deduplication exercise in 2024 using open-source tools and found that roughly 30 percent of the images in its 80,000-photograph archive were exact or near-exact duplicates consuming unnecessary server storage. The experience illustrated both the scale of the problem and the relative accessibility of off-the-shelf solutions — tools that municipal agencies have been slow to adopt.

The Road Ahead

Three practical steps define what cities that have moved ahead look like. First, they set a single nodal agency — not four competing directorates — to own the deduplication mandate. Second, they publish a data standard so that images ingested from new sources are hash-checked on entry rather than retrospectively cleaned. Third, they attach a budget line and a deadline to the work rather than leaving it inside a broader digitalisation aspiration.

For Delhi, the Phase 4 Metro expansion creates a forcing function. The DMRC has set an internal target of integrating its smart-card customer database with the state's OneDelhi app by the time the Janakpuri West–RK Ashram Marg stretch opens, a date the corporation has indicated falls in late 2027. Duplicate photographs in the identity layer of that integration will cause exactly the kind of card-rejection errors at Rohini sector stations and Dwarka interchange points that erode public trust in the system far more visibly than a slow land registry. Fixing the backend now, before millions of new commuter records are added, costs a fraction of what a post-launch cleanup would require. Mumbai learned that lesson. Delhi still has a narrow window to act before it has to relearn it the hard way.