As in the case of demountable systems, a temporary system is only functional when the barrier
is fully erected before the water rises to the lowest safe permanent protection level. The
temporary flood protection system therefore includes the barrier which includes the temporary
elements, the seals and joints within the structure, the interaction between the structure and the
surface or bedding layer, the end connections and fixing details. The temporary flood
protection system also includes the operational procedures required to install the system such
as mobilisation, installation and closure processes.
It should be noted that while the foundations for permanent and demountable systems would
be designed as part of the installation of the permanent parts, temporary systems by their
nature would be placed on whatever surface or existing foundation is available. The bedding
surface therefore needs to be along a prepared and designated alignment. The need to ensure
suitability of various locations, terrain or underlying soil is therefore a requirement for
temporary systems. As a result of this, the ability of temporary systems to prevent
groundwater seepage and uplift pressures on it is normally dependent on that of the existing
subsoil or structure onto which they are erected.
The performance of a fully erected temporary system is dependent on its barrier as well as its
interaction with its subsoil and its end joints and details. The type of terrain, formation layer
and sub-soil suitable for use with a particular form of temporary barrier as well as the seepage
characteristics of the sub-soil is critical to the ability of temporary barriers to provide flood
protection.
Typical elements of a temporary protection system are shown in Figure 2.3.