Perth Leads Australia on Duplicate Image Replacement — But Global Cities Are Moving Faster

Perth's major public agencies have cleared roughly 60 percent of flagged duplicate images from their citizen-facing digital platforms since a statewide audit began in March 2025, according to figures tabled at a WA Digital Government directorate briefing last month. The work sounds unglamorous. The consequences of ignoring it are not.

Duplicate imagery — photographs, diagrams and maps that appear multiple times across government websites, transport apps and planning portals — slows page-load times, inflates storage costs and, more critically, creates legal exposure when an outdated image contradicts current policy or misrepresents a development site. The issue has sharpened in Perth as Metronet rail construction has reshaped suburbs from Forrestfield to Yanchep, leaving planning portals littered with pre-construction photography that no longer matches ground truth.

What Perth Is Actually Doing

The City of Perth and the Department of Planning, Lands and Heritage are the two agencies furthest along. The City of Perth's digital team began a structured deduplication pass across its property and event image libraries in October 2024, prioritising the Northbridge precinct and the Perth Cultural Centre on James Street — both areas where construction hoardings, temporary art installations and streetscape changes had generated hundreds of near-identical but technically distinct image files over a five-year period. The department's GIS portal, which planners and developers use daily, had accumulated duplicate aerial tiles going back to the 2019 cadastral resurvey.

Transperth's journey planner app is a separate and slower story. Photographs of stations on the new Forrestfield-Airport Link, which opened in stages from 2022, still pulled legacy thumbnails sourced from concept renders in some interface states as recently as April 2026, according to a review published by the WA Auditor General's office. The agency has set an internal deadline of September 30, 2026 to reconcile all station imagery against current photography.

The practical machinery involves perceptual hashing — an automated technique that assigns a fingerprint to each image and flags near-matches for human review — combined with manual triage by contracted digital asset managers. The City of Stirling, which manages one of Perth's largest local government websites, brought that work in-house in January 2026 after outsourcing it since 2022, citing cost savings it estimates at around $180,000 annually. The suburb of Scarborough, heavily photographed during its foreshore redevelopment, generated the highest single volume of flagged duplicates in the City of Stirling audit.

How Perth Compares Globally

The honest comparison is uncomfortable. Singapore's Government Technology Agency completed a whole-of-government image deduplication program across 94 ministry websites in 2024, finishing eight months ahead of its original schedule. Amsterdam's municipality, which restructured its digital asset management under a single content delivery network in late 2023, reports less than two percent image duplication across its public portals as of June 2026.

Vancouver and Toronto — cities often benchmarked against Perth for population growth trajectory and resource-economy parallels — sit closer to Perth's position. Vancouver's city portal audit, begun in 2024, is running approximately six months behind its own targets, partly due to contractor shortfalls. Toronto's equivalent program stalled after a procurement dispute in late 2025.

Auckland is the most instructive comparison for Perth specifically. Both cities are managing digital infrastructure against a backdrop of rapid suburban expansion and major transit construction. Auckland Council completed its first full deduplication cycle in May 2026, covering 1.4 million image assets across 18 department websites. Perth's comparable asset count, across state and major local government systems combined, is estimated at just over 900,000 — suggesting the task here is proportionally smaller but the progress slower relative to the timeline Auckland set.

For residents and developers, the immediate practical advice is straightforward: if you are accessing planning imagery or site photography through any WA government portal for a development application or property purchase decision, cross-reference against the Landgate portal's most recent aerial update, dated February 2026, rather than relying on embedded site photography which may predate recent Metronet or urban infill works. The Department of Planning has flagged its imagery refresh for Ellenbrook, Alkimos and Yanchep as the next priority tranche, with updates scheduled to begin loading from August 2026.