Applications of Life-Cycle Cost Analysis in Water and Wastewater Projects: Lessons from European Experience - Governing the Nexus: Water, Soil and Waste Resources Considering Global Change - page 137

the technical term for it, and the related research investigates the effects of urban
form on public costs induced by investment, operation and maintenance of net-
work-related technical infrastructures (such as water and energy supply, sewage
disposal and roads). Several research projects as well as implementation projects
have been dealing with this topic for more than a decade (Burchell et al. 1998 ).
Long-term cost effects, which are to be expected for different paths of settlement
development, are in the foreground of these considerations and were mainly dis-
cussed under growth conditions. In light of stagnating and shrinking populations,
this topic has been receiving increasing attention in practical settlement develop-
ment in Europe and Germany, in particular (e.g. Schiller and Siedentop 2005 ;
Siedentop and Fina 2008 ). This takes into account a distinct and often empirically
con c infrastructure costs per user.

The higher the density is, the lower the per capita length of water distribution lines
or sewer collection lines, roads, etc. is (see Fig. 10 ). This is true for most types of
settlements found in developed countries. Exceptions from this rule can occur in
metropolises with extremely high densities. Due to multifaceted overlaps of usage,
additional infrastructures are necessary (e.g. in underground or vertical develop-
ment through high-rise buildings). In sparsely populated rural regions, the infra-
structural standards frequently do not meet those of urban settlements, so that the
dependency between infrastructure costs and density does not apply that strictly.
The principles of an approach for infrastructure cost calculation to support
regional planning are shown in Fig. 11 . First, the physical model is compiled taking
into account the physical parameters of settlement structures, variations of infra-
structure-equipment and settlement development. Second,

rmed correlation between urban density speci

the cost model is

developed based on these physical parameters. It incorporates speci c capital costs,

Fig. 10 Correlation between density and infrastructure costs. Source I Ö R