Motivation
Based on the key product Alternative Regional Water Production and Transfer Strategies, this Key Product provides decision support by assessing these strategies according to the preferences of decision-makers and stakeholders. Due to the long temporal scope and inherent complexity of the decision problem, multiple possible consequences must be considered simultaneously. Adequate decision support thus should seek to understand the decision problem in its entirety and include objective and subjective information. Therefore, the assessment is conducted via selected methods of Multi-Criteria Analysis (MCA). The objective of this key product is to structure the decision problem and elicit the preferences and criteria of the decision makers and stakeholders to identify the most preferred Regional Water Production and Transfer Strategy. Factors responsible for a positive or negative evaluation of a particular strategy are identified and highlighted. The results provide the basis for strategy implementation or support consensus building.
Methodology
We collaborated with project partners, decision-makers and stakeholder to perform a MCA. The evaluation of the SALAM strategies with a planning horizon until 2050 is a highly complex decision problem with multiple conflicting criteria. The MCA method shows which factors drive the choice for a certain strategy. In particular, we evaluate the performance and consequences of alternative water strategies in Palestine and Jordan based on technical, economic, ecological, social, and political criteria. We apply the PROMETHEE method, which is an outranking method based on pairwise comparisons of the performance scores of different alternatives. An assessment is possible without defining uniform units of measurements and scales for all criteria. Additionally, outranking methods elicit preferences during the decision support process. However, a single decision maker cannot be identified, because many authorities and stakeholders with diverging interests take part in discussions about the management of water resources and infrastructures. Hence, we specifically apply the Multi-Actor Multi-Criteria Analysis (MAMCA) method with PROMETHEE to reveal possible trade-offs and indicate compromise solutions.
State of Works
The following selected Regional Water Production and Transfer Strategies were regarded as most promising and further assessed via the MCA method PROMETHEE:
Regional 1b: Construction of seawater desalination plants near Netanya and Aqaba. Total freshwater deficit of West Bank (323 MCM by 2050) is supplied through production at Netanya. Freshwater deficit of Jordan is supplied by production at Netanya with volumes up to 412 MCM by 2050 and Aqaba (300 MCM by 2050).
Regional 3c: Construction of seawater desalination plants near Haifa and Aqaba. Total freshwater deficit of West Bank (323 MCM by 2050) is supplied through production at Haifa. Freshwater deficit of Jordan is supplied by production at Haifa with volumes up to 412 MCM by 2050 and Aqaba (300 MCM by 2050). The network is routed routed through Lake Tiberias and enters West Bank through the Northern Cluster.
Regional 3d: Construction of seawater desalination plants near Haifa and Aqaba. Total freshwater deficit of West Bank (323 MCM by 2050) is supplied through production at Haifa. Freshwater deficit of Jordan is supplied by production at Haifa with volumes up to 412 MCM by 2050 and Aqaba (300 MCM by 2050). The network is routed routed through Lake Tiberias and enters West Bank through the Northern and Jordan Valley Cluster.
The objectives of the decision-makers, the resulting evaluation criteria and their relative importance, expressed as criteria weights, were elicited with project partners and regional partners from Palestine and Jordan. The results are depicted in Table 1 and Table 2. The criteria weights have been determined according to the SIMOS method.
Calculation of specific water costs and total investments was based on network data and elevation profiles to determine pumping station capacity and quantity. As depicted in Table 3, the water costs for transferring from Aqaba are comparably higher due to less freshwater supply volume, longer transfer networks and higher pumping energy requirements. Approximately 75-80% of specific transfer cost are incurring due to energy demands. Furthermore, implementation of a hydropower plant at Lake Tiberias could decrease the cost of desalination at Haifa through energy proceeds.
Outlook
Once the performance of alternatives has been fully quantified, the subsequent evaluation according to PROMETHEE will yield outranking relations, which show the preference between all pairs of alternatives. These outranking relations are then aggregated over all alternatives, which yields positive and negative outranking flows. These will be used to create a partial ranking of alternatives, where incomparability can be displayed. Aggregating positive and negative outranking flows to the net outranking flow, also called PROMETHEE II, yields a total ranking order of the alternatives to be assessed. A sensitivity analysis will reveal whether inherent uncertainties in the data lead to different rankings.