This paper begins to identify the impact of dryland salinity on the performance and longevity of the road asset, and highlights a need to increase awareness amongst road managers about the extent of dryland salinity and the potential for accelerated impacts in the future. Some insight into how high watertables and salinity are currently affecting road assets in Australia is presented, along with an explanation of the apparent mechanisms associated with groundwater entering road formations. These impacts may require changes to the way roads are designed, constructed and maintained, to ensure that an acceptable service life is achieved. The National Land and Water Resources Audit (undertaken in 2000) provides an indication of the extent of road infrastructure potentially at risk from dryland salinity in each state. Projections to the year 2050 indicate that the total length of roads affected will increase by more than a factor of three. Annual salinity damage cost estimates for 'high risk' roads only range between $50 million and $100 million in 2000, increasing to $158-380 million by the year 2050. (a).
Abstract