EDP-supported development of economically optimized line renewal strategies by damage analyses

The criterion for the replacement of lines in many water supply enterprises is still their age. Economically aligned strategies of the network renewal do still not exist in many places. In the context of a federal research project at the ESWE Supply PLC in Wiesbaden, a software for economical rehabilitation planning as well as the appropriate database are created. From damage data and the use of economical algorithms this program sets up damage prognoses for individual line sections of the supply network. By inclusion costs of renewal and sanitation measures the expected costs in the future can be calculated on the basis of these damage prognoses. The line sections can be sorted according to different criteria in the program. Thereby, the network planner has the possibility to quickly and efficiently finding the exact line sections of the network which must be renewed or sanitized. In parallel to the software development, investigations into the causes of damage like aggressive soils or earth movements were executed. They supply further important information for the specification of the decisions of the network planner. This information was integrated into the resource information system and can be recalled for planning purposes. Thus the combination of an economical rehabilitation program and resource information system, provides an optimal package for decision making to aid the network planner.