How Adelaide's property and planning records ended up full of duplicate images — and what it took to get here

South Australia's Land Services SA holds millions of scanned documents covering every titled parcel of land in the state, from the sandstone terraces of North Adelaide to the new housing estates pushing out past Angle Vale. A significant share of those records, according to a Land Services SA internal process review circulated to agency stakeholders earlier this year, contain duplicate image files — the same scanned page stored twice, sometimes three times, under different document reference numbers. The problem did not arrive overnight.

The duplication issue matters now because the state government is mid-stream on two major digital infrastructure projects that depend on clean, reliable land records. The first is the Lot Fourteen precinct on North Terrace, where technology firms and space-sector tenants are building data pipelines that pull on SA government open-data feeds, including cadastral records. The second is the broader AUKUS-related defence infrastructure buildout, which requires rapid, accurate title searches across parcels in the LeFevre Peninsula and north of Osborne where Commonwealth acquisitions are in progress. Dirty data slows both.

Three systems, one mess

The duplication problem has its roots in the early 2000s. SA's land title office ran on a legacy LOTS (Land and Other Titles System) platform for decades. When Land Services SA was privatised in 2017 — the state government sold a 40-year concession to a consortium led by First State Super and Macquarie Infrastructure for approximately $1.6 billion — the new operator inherited LOTS, a partially migrated interim database, and a backlog of physical documents that had been batch-scanned by an external contractor between 2009 and 2014. Each of those three sources used different naming conventions for image files. The migration scripts written at privatisation were not designed to detect cross-source duplicates, only within-source ones.

By 2020, the volume of affected records had grown large enough that conveyancers on Grenfell Street were occasionally pulling up the same instrument image twice when running title searches, with no obvious flag in the interface. The Law Society of South Australia raised the issue with Land Services SA formally in 2021, and the two organisations agreed on a joint working group. Progress was slow. The Covid-19 period pushed the working group's timeline out by at least 18 months, according to correspondence published under Freedom of Information requests by this masthead last year.

Why the fix is harder than it sounds

Removing a duplicate image from a land title record is not as simple as deleting a file. Every stored image is linked to an audit chain that must remain intact for legal reasons under the Real Property Act 1886 (SA). Any deletion requires a parallel entry in the audit log confirming the removed file was a true duplicate and not a distinct version of a document. For a database running into the tens of millions of records, that is an enormous manual and semi-automated task.

Land Services SA contracted Adelaide-based data management firm NEC Australia in late 2024 to build an automated deduplication pipeline. The contract, listed on the SA Government's ICT procurement register, was valued at just under $4.8 million over 18 months. The pipeline uses perceptual hashing — a technique that generates a short fingerprint from image content rather than file metadata — to flag likely duplicates for human review. As of the most recent quarterly report to the Department for Housing and Urban Development, the pipeline had processed roughly 40 per cent of the pre-2015 backlog.

For everyday property buyers and sellers, the practical impact is already visible in slightly faster title search turnaround times through the SAILIS online portal. Conveyancing firms on King William Street report that the incidence of double-image returns in search results has dropped noticeably since the NEC pipeline went live in January 2025, though a full resolution of the backlog is not expected before mid-2027. Anyone with a pending settlement or a development application dependent on accurate title history should confirm with their conveyancer or solicitor whether their specific certificate of title falls within the portion of the database already cleaned — and follow up with Land Services SA directly if records look inconsistent.