The need for improved planning and design of natural resources is recognised with respect to sustainability. Water sensitive urban design (WSUD) is an example of improved practices and can

contribute to the sustainability of developments, and the systems in which they are nested. This contribution is dependent upon the objectives of the development and the resources available to the development.

Sustainability is a dynamic characteristic of a system that must be assessed and managed over time. WSUD addresses the sustainability of water resources within a development by improving the reliability of supply in the long term and reducing the risk of failure. WSUD is vital to the sustainability of a development but must be evaluated with respect to the overall sustainability of the development and adjacent systems. For this to occur all resources available to development must be considered and an assessment tool developed that acknowledges the complexity of available resources and the interactions between those resources and adjacent systems.