AbstractThe objective of this study was to investigate the economic and environmental appeal of the world’s largest glass fiber–reinforced polymer (GFRP) RC flood mitigation channel, which was built in Jazan (Saudi Arabia). The Jazan flood mitigation channel (JFMC) is a 21.3-km-long channel completed recently in the southwest area of Saudi Arabia on the outskirts of the new Jazan Economic City (JEC), which is an advanced industrial zone and encompasses an important network of high-end facilities. A deterministic approach is applied to a comparative life-cycle cost (LCC) analysis, and sensitivity analyses are used to predict the impact of uncertain factors, such as discount rate and maintenance periods, on the LCC analysis of JFMC. Additionally, the environmental credentials of the GFRP-RC channel are investigated through a life-cycle assessment (LCA) analysis. The LCA analysis is performed from cradle to gate and from cradle to grave, specifically from product stage (or resource extraction) to end of life (EoL). The JFMC is designed for a 100-year service life, and the LCC and LCA analysis performed are in compliance with the international standards ISO 15686-5, ISO 14040:2006, and ISO 14044:2006. The obtained economic and environmental results are compared to the results obtained from an epoxy-coated steel (ECS)-RC channel alternative that was originally designed. The results show the significant life-cycle benefits of the preferred GFRP-RC alternative from both an economic and environmental perspective, advancing the body of knowledge available for LCC and LCA of flood control and mitigation concrete channels reinforced with FRP materials.