Sustainability Evaluation of a Concrete Gravity Dam: Life Cycle Assessment, Carbon Footprint Analysis, and Life Cycle Costing

Abstract

Exploring the life cycle of infrastructures, like dams, is important for decision-makers since it allows for evaluating its overall sustainability, and identifying ways to balance the benefits and costs of dam development. In this study, the life cycle assessment (LCA) of the existing concrete gravity Pine Flat dam in the stages of construction to destruction, disposal, and recycling is investigated through ReCiPe 2016 methodology and the effect of two approaches of seismic retrofitting and non-retrofitting in the life cycle of the dam is studied. For a comprehensive understanding of the sustainability of the dam's life cycle, carbon footprint analysis (CFA) and life cycle costing (LCC) are also conducted to identify the main sources of greenhouse gas (GHG) emissions and evaluate the economic performance. These demands begin by assessing the dam’s life cycle across three distinct stages, namely, initial construction, seismic retrofitting, and decommissioning, assuming recycling 20% of demolished concrete for the last stage. The outcomes of the evaluation are then presented for four different life cycle scenarios. The findings have underscored the importance of reducing air pollution and emphasize that human health is the most significant environmental concern as compared to the ecosystem and resource indicators. The concrete recycling considered during the decommissioning stage led to a 32% reduction in pollution caused by the dam disposal process. Additionally, the effect of retrofitting dams in decreasing environmental impact indicators such as carbon footprint and human health has been considered when compared to dam disposal. The economic and environmental costs of retrofitting Pine Flat dam were obtained about half of the equivalent expenses for its disposal and recycling stage.