The Use of AHP (the Analytic Hierarchy Process) Method for Irrigation Water Allocation in a Small River basin (Case Study in Tampo River Basin in West Sumatra, Indonesia)

Abstract

"This paper presents that the water management outcomes in a small river basin are the results of the interaction between the social aspects of water users and the physical aspects of the water resources. The analysis using a cultural ecology perspective to assess the relationship between these two aspects has provided a reasonable rationale to affirm that many social aspects of water users cannot be ignored when deciding or implementing a physical program that may influence the water resources system. Previous experiences have shown that any physical projects in the Tampo basin, West Sumatra, Indonesia have increased the withdraw water at the upstream part and reduce the opportunity for downstream part. As a result, changes in the demand and supply pattern in the basin have created conflict between water users along the river. It is thus clear that an integrated approach in designing and implementing a water resource development and management strategy for the Tampo basin must be used. In this regard, this study has combined the socio-institutional and physical assessment of water resource management in this basin with the AHP method to obtain the most acceptable alternative of irrigation water allocation for all water users along the river course. Since the purpose of this method is to involve the stakeholders in the decision making process, the AHP method has shown its capability to allow the stakeholders to participate in expressing their preferences to compare alternatives. The process of obtaining their preferences is done after the presentation of and discussion about the impact analysis of their proposed alternatives. Besides having the final conclusion of the acceptable water allocation pattern, this study has also collected such comments and suggestions from the spoke-persons in using the AHP. One important constraint in using the AHP is a time consuming process for ordinary small farmers in the case site. Some tricks and shortcut methods are then used to create the process of discussion and value judgments as effective as possible."