Perth Agencies Scramble to Fix Duplicate Image Problem Swamping Property and Government Listings

Duplicate images have become a live operational headache for Perth businesses and government agencies this week, with real estate portals, local government websites and defence procurement platforms all reporting catalogues bloated by redundant photographs that slow load times, confuse users and, in some cases, breach tender compliance rules.

The problem is not new, but it has sharpened considerably in 2026. The twin pressures of a housing demand surge — driven partly by immigration linked to AUKUS construction activity at HMAS Stirling on Garden Island — and a Metronet-fuelled suburban expansion have pushed the volume of property listing images on platforms such as REIWA.com.au to record levels. More photos being uploaded faster means more duplicates slipping through without a human reviewer catching them.

What Happened This Week

On Tuesday, the City of Stirling updated its online development application portal, which covers suburbs from Scarborough to Balcatta, after internal auditors flagged that several hundred planning submission images had been filed twice across different application numbers during the June quarter. The duplication was traced to a batch-upload tool used by multiple drafting firms operating along the Wanneroo Road corridor. The city did not specify a dollar cost to remediation, but the fix required two full days of IT staff time to triage and remove the redundant files.

Separately, a Leederville-based digital marketing agency confirmed to industry newsletter PerthTech Roundup this week that it had deployed a perceptual hashing library — a type of software that assigns each image a fingerprint and flags near-identical matches — across client accounts managing listings for residential developments in Ellenbrook and Alkimos. The agency said the tool cut duplicate image instances by roughly 70 per cent in its first month of testing, though that figure applies only to that firm's own client portfolio and has not been independently audited.

The timing matters because the WA State Government's current budget cycle has emphasised digital-service efficiency across all agency platforms. The Department of Planning, Lands and Heritage, which manages the online DAP (Development Assessment Panel) submission system used for major projects from Perth CBD to Fremantle's Victoria Quay, updated its file-submission guidelines in May 2026 to explicitly warn that duplicate images within a single submission package could trigger a compliance review and delay determination by up to 10 business days.

Why It's Harder to Solve Than It Looks

The technical fix — perceptual hashing, reverse-image lookup, or simple MD5 checksum comparison — exists and is relatively cheap to deploy. The harder part is workflow. In real estate, photographers shooting properties in growth corridors like Brabham or Piara Waters often supply the same hero shot in multiple resolutions for different platform specifications. Each version registers as a unique file by name but is visually identical, and automated tools need to be tuned carefully or they flag intentional multi-resolution sets as duplicates.

REIWA, the peak body for WA's real estate industry, updated its agent portal terms in January 2026 to require that listing photo sets contain no more than 50 images per property, a rule partly aimed at reducing database bloat. The 50-image cap replaced a previous limit of 40, meaning the ceiling went up even as the duplicate problem persisted — a tension the industry is still working through.

For government and defence-adjacent procurement, the stakes are higher. Tender documents submitted to the WA Government's Tenders WA portal for projects connected to the Indian Ocean Strategy or AUKUS supply-chain work must meet strict file-integrity standards. A duplicate image inside a 500-page PDF submission can, in some cases, trigger an automated rejection before a human ever reads it.

Agencies and businesses dealing with the issue have a clear short-term path: adopt perceptual hashing tools before the next major upload cycle, audit existing libraries for near-duplicate clusters, and update internal style guides to flag multi-resolution delivery as a separate category exempt from duplication rules. The City of Stirling has indicated it will publish updated submission guidance for its planning portal before the end of July. Other councils in the northern suburbs growth corridor are expected to follow.