A dynamic approach for evaluating the sustainability performance of infrastructure projects

Abstract

Implementation for sustainable development principles has been attracting increasing attention across various sectors including the construction industry since the evolution of the concept in the publication of Brundtland Commission Report in 1987. In line with this development, implementation of infrastructure construction projects has been given particular attention as they have more significant impacts on the environment, society and economy. It is considered that proper development and operation of infrastructure construction projects can contribute significantly to the mission of sustainable development. However, it appears that there is no method developed for evaluating the sustainability performance of infrastructure projects, which concerns the performance across economic, social and environmental aspects. There are various traditional methods for project evaluation, typically including economic appraisal, environmental impact assessment, social impact assessment, and life cycle analysis. However, these methods are usually applied to assess the performance of construction projects from the perspectives of economic, social and environmental dimensions respectively. The absence of an integrative approach has been leading to the lack of consideration on the balance between economic, social and environmental performance from implementing an infrastructure project. In recent developments, several studies have been contributed in developing methodologies to incorporate project performance across economic, social and environmental dimensions collectively. One major weakness however in applying these methods is that they do not consider the impacts of dynamic interactions between various factors on project performance. In fact, it is essential to appreciate the dynamic impacts of various factors on project performance during the process of implementing projects. This appreciation is particularly important for those large-scale infrastructure projects, which engage in extensive investments and long period of construction and operation time. It is therefore the aim of this study to investigate a dynamic project assessment approach which can not only consider project performance collectively across economic, social and environmental dimensions, but also take into account the impacts of the dynamic interactions of various factors on the project performance. The focus of this study will be given to highway projects during construction and operation stages to illustrate the application of a dynamic approach for evaluating sustainability performance of infrastructure projects. The research objectives include the identification and selection of the indicators for evaluating the sustainability performance of highway projects; the development of a dynamic model for evaluating the sustainability performance of highway projects during construction and operation stages; and the demonstration of applying the dynamic evaluation model by using a practical case. Data employed in this study were collected from multiple sources including critical literature reviews, examination on official guidelines/policy papers, interview discussions, and surveys. Research methods include statistical analysis, and system dynamics modeling principles. The major contribution of this study is the introduction of a new methodology for evaluating the sustainability performance of highway projects, that considers collectively the project economic, social and environmental contributions. It provides an alternative which mitigates the weakness of static and isolated evaluation built in traditional evaluation approaches. Other key results from this research include the identification of the key performance indicators for evaluating the sustainability performance of highway project. The dynamic approach introduced also captures a holistic view on a system being assessed. It provides a simple and applicable tool to assist project decision makers in assessing the feasibility of implementing a highway project from the perspective of sustainability performance. The application of the tool can help identifying the poor performance areas, thus corrective methods can be taken to make improvement. The dynamic approach supports the analysis on the impact of dynamic interactions between various factors on project sustainability performance. An understanding on this impact allows project decision-makers to know how a particular level of project sustainability performance is attributed. Improvements in sustainability performance can therefore be made if the performance level is not up to satisfactory level by the adjustments of certain dynamic factors.