Task 4.1   Choice of scenarios

Long-term rehabilitation scenarios must be designed for local networks in a systematic way and specified for different options of rehabilitation to show the expected development for selected performance indicators in a 10-20 years perspective. This will serve as an important support for strategic decisions. Reference scenarios have been designed on the basis of the expected use of the scenario manager according to the selected PIs (Task 1.3).

Task 4.2   Impact functions on technical-economic predictable PI

The scenario manager shows the expected financial needs for network rehabilitation programmes and their impacts on burst and leakage rates, maintenance cost, service reliability, residual lifetimes of pipes, asset values and external costs. The scenario manager includes several modules. Among those are:

• Expected network survival (i.e. pipe burst or leakage prediction model)
• Expected service reliability (i.e. water supply service reliability model)
• General cost of rehabilitation measures
• Effect of various measures on relevant and predictable PI
• Routine for investment calculations
• Routine for social impact estimation

Task 4.3   Multi-criteria evaluation of rehabilitation programmes

The procedure has been developed for selecting the rehabilitation programme, which is the most appropriate out of a multitude of candidates. This procedure has been included in the CARE-W prototype (WP5).