By the Numbers: The Hidden Cost of Duplicate Images Swamping Central Coast Council's Digital Records

Central Coast Council is sitting on a digital storage problem it can barely quantify. Across the organisation's document management systems, planning portals and community engagement platforms, duplicate image files — the same photograph or scan saved multiple times under different file names — now account for an estimated 30 to 40 percent of total storage consumption at mid-sized Australian local governments, according to figures published by the Australian Local Government Association in its 2025 digital infrastructure review. For a council still rebuilding its financial systems after emerging from state administration in 2021, the waste is more than a housekeeping issue.

The problem has sharpened in 2026 because of two converging pressures. First, the council's Gosford CBD renewal program has generated thousands of planning images, heritage photos and community consultation documents since the Gosford Activation Precinct framework launched. Second, the NSW Government's push to digitise development applications — mandatory for all councils under the state's Planning Portal since March 2024 — has flooded local servers with submissions that frequently contain the same site photographs attached to multiple lodgement forms.

What the Data Actually Shows

Storage costs are not abstract. Commercial cloud storage for government-grade data in Australia typically runs between $80 and $120 per terabyte per month when security and compliance requirements are factored in, based on pricing schedules published by Services NSW for whole-of-government procurement panels. A council that trims 10 terabytes of duplicate files from its active storage can save close to $14,400 a year at those rates — before counting the staff time spent navigating cluttered file directories.

The problem is measurable at the local level. The Central Coast Regional Library network, which operates branches including Gosford Library on Donnison Street and Wyong Library on Margaret Street, migrated its digital catalogue and community archive to a new content management system in late 2024. During that migration, the library service identified that roughly one-in-three image files in its local history collection were duplicates — either exact copies or near-identical scans made at different resolutions. The deduplication process, carried out over three months, reduced the collection's raw file count by more than 28 percent.

Community organisations face the same arithmetic. The Central Coast Community News, which maintains a photographic archive of regional events stretching back to the early 2000s, has noted that automated uploads from contributors frequently generate multiple copies of identical images. Managing that backlog manually costs volunteer hours that small community publishers can ill afford.

Why Automated Detection Hasn't Solved It

Software tools for detecting and removing duplicate images have existed for years, but uptake among NSW local councils has been uneven. Perceptual hashing — a technique that identifies visually similar images even when file names or sizes differ — is now standard in enterprise-grade document management platforms, but many councils, including Central Coast, are still running legacy systems that predate those capabilities. The council's own IT renewal roadmap, tabled at the March 2026 ordinary meeting, listed document management modernisation as a priority for the 2026–27 financial year, with a budget allocation to be confirmed in the upcoming annual operational plan.

The NSW Department of Planning's e-Planning team has flagged the duplicate-submission issue to local government stakeholders, though no mandatory deduplication standard has been gazetted as of July 2026. Until one arrives, the burden falls on individual councils and their IT staff.

For ratepayers on the Central Coast — where the median house price in Gosford sat at approximately $830,000 in the June 2026 quarter according to CoreLogic's monthly hedonic index — the connection between efficient council IT spending and service delivery is direct. Every dollar absorbed by redundant storage infrastructure is a dollar not spent on roads, drainage or the flood resilience works that communities from Tuggerah to Toukley are waiting on. Residents wanting to understand how their council manages digital assets can request the relevant section of the IT renewal roadmap under the Government Information (Public Access) Act 2009, commonly known as a GIPA application, through the council's Wyong Road headquarters.