One of the primary responsibilities of Local Government is to maintain a complete register of its assets – road networks and infrastructure, sewerage schemes and so forth. As assets can often be best managed by a spatially oriented system Atherton Shire Council like many other Councils around Australia sought a GIS solution.
In 1995, Atherton Shire decided to undertake a project replacing in its entirety the existing Digital Cadastral Database (DCDB) with a spatially accurate cadastral database.
A small rural shire in North Queensland, Atherton had found the existing DCDB, compiled by the Department of Natural Resources, Queensland, had spatial inaccuracies of between two metres and 200 metres.
Council aimed to develop a database that would be accurate to approximately five centimetres in urban areas and 30 centimetres in rural areas.
The cadastral database is the administrative base layer of the Shire’s Geographic Information System (GIS), providing a full register of assets and environmental information.
A project such as this presented enormous challenges. As such, this type of database had largely been the domain of the State Government, for its creation, maintenance and accuracy.
As far as Atherton Shire Council is aware, this type of project has not been attempted by any other rural Shire in Queensland or Australia.
Methodologies used for data input, problem solving, field survey requirements, and adjustment of data required improvisation and innovation. Over 100 primary control stations were established across the Shire.
A series of traverse networks were run between primary control stations that made sufficient cadastral connections to property corners. All bearings and distances from original plans of survey were entered into ArcInfo.
An affine transformation was performed on the information. The data was then given a polygon topology and stitched together to form one completed layer. Finally rigorous checks proved the integrity of the data.
The project was very cost effective with the bulk of the work completed in house.
For further information please contact Sandro Condurso, telephone (07) 4091 0727.
