If it is not possible to construct permanent protection to the required level, a reliable flood
forecasting and warning system exists, local and legal issues are favourable and a reliable
organisation to manage the system exists, then the use of temporary or demountable protection
systems should be further considered.
Having decided on the use of a temporary or demountable system, the next two sections
describe the categorisation of the available systems and the process of choosing appropriate
systems for various conditions and requirements.