Ecosystem services review of water projects

Abstract

Water projects are typically evaluated using benefit cost analysis. Ecosystem services are the direct and indirect benefits that people obtain from ecosystems. Many of these benefits are ignored in benefit cost analysis, because of the absence of markets and the limited information or understanding of how the benefits from ecosystem services are produced. This paper reports the methods used to assess the impact of a water storage dam on the flow of ecosystem services in a river system. We review the range of ecosystem services that are available in a river system and examine how the flow of ecosystem services can be altered by water storage and flow augmentation through the construction of a dam. In order to list and quantify ecosystem services an attempt is made to determine a suitable site specific set of ecosystem service indicators for the Opuha‐Opihi river system case. We draw inferences about shifts in the value of ecosystem services that might arise from water projects in other contexts.