The maintenance of water/ gas distribution and sewer networks remains a permanent task due to the extent of necessary measures and the linked budget demands and therefore requires future-oriented strategies. The essential challenge of developing sustainable strategies consists in finding a way, which represents a long-term compromise between the requested service level and the costs. An important foundation for steering the development of costs (and within costs the issue of fees and tariffs) and the condition is the knowledge about the actual constructional state and the future aging of the network. Generally, pipe based infrastructure networks are more or less subject to a continuous aging process. Here the aging pattern may vary clearly depending on the pipeline-specific characteristics, respectively the combination of characteristics (age, actual constructional state, DN etc.). Against the background, that the infrastructure networks extant today have been created in steps and in periods of different execution variations and laying qualities it can be assumed that the future demand for rehabilitation will strongly vary. A maintenance planning, in which the net-specific deterioration of condition occurring in the future is not realistically analyzed, inevitably leads to a misinterpretation of the demand for rehabilitation and financial means. In order to guarantee a long-term security in planning, it is therefore indispensable to analyze the characteristics of the local net aging and to include them on the scope of creating a strategy.