Environmental Impact Assessment of Transport Infrastructure Transformation Projects: A Case Study of the Utrecht Science Park

Abstract

Keeping urban areas accessible and attractive under the stress of population growth, while also facilitating the mitigation of climate change and achieving climate goals, is an urgent and complicated challenge. The Utrecht Science Park (USP) currently faces this challenge, having made plans to transform its transport infrastructure. Consequentially, this study aims to develop a model that can assess the environmental impact of the USP transport infrastructure transformation project and that provides an evaluation of possible mitigation measures. Following the methodological steps of environmental impact assessment, the Transport Infrastructure Project Environmental Assessment (TIPEA) model was developed. The TIPEA model uses life cycle assessment as a supportive tool to provide a holistic environmental assessment. The TIPEA model has three transformation phases incorporated: the construction, use and demolition phase. In addition to most studies, the use phase includes passenger displacement. Furthermore, the TIPEA model has the ability to compare the environmental impact of two system boundaries. The system boundaries examined are passenger displacement on USP grounds (B1) and commute displacement (B2). The application of the TIPEA model to the USP transformation project has led to two important conclusions. First, the original plans have the ability to reduce the environmental impact of the USP. Depending on the chosen system boundary, the embodied environmental impact of the transformation on the global warming potential is paid back within 9.5 years (B1) or 13.3 years (B2). However, this is not in time to facilitate the aim of the Utrecht University to reach climate neutrality in 2030. Therefore, the environmental impact must be reduced further to reach this aim. Second, as the use phase contributes to up to 67.5% (B1) or even up to 99% (B2) of the global warming potential, it has a significant effect on the environmental impact of the project and a high mitigation potential. To reduce the environmental impact of the USP transformation project, the effect of three mitigation measures has been studied: inducing a modal shift in passenger displacement, using alternative asphalt road surface layers and constructing an alternative type of parking garages. All three possible mitigation measures have the potential to mitigate the environmental impact of the project. However, the extent to which these measures mitigate the environmental impact varies significantly between the measures and is greatly dependent on the chosen system boundary. Thereby, the results highlight the importance of setting proper system boundary conditions and climate goals in order to effectively mitigate climate change.