The Road Formation is the surface of finished earthworks on which a road pavement is constructed. It includes the earthworks, the general shaping of the road and basic drainage, but excluding stormwater infrastructure.
The Glossary of Austroads Terms defines the "formation" as "the surface of finished earthworks, excluding cut or fill batters."
The financial reporting standards require that major parts (significant components) of assets be separately identified and depreciated. This has been interpreted to mean that the road formation should be separately valued & depreciated.
Depreciation of Road Formations
Road formations are typically depreciated over a very long period, but Interpretation 1055 Accounting for Road Earthworks suggests that some but not all road earthworks do not have a limited useful life, and don't need to be depreciated.
The useful life of a road formation will vary considerably due to a wide range of environmental factors.
The table below shows the useful life for road formations adopted by Councils or published elsewhere. At the moment a useful life of about 150 years seems to be typical. Please feel free to add your Councils information below.