Dynamic Simulation for Sustainable Construction and Demolition Waste in Island Regions

Construction and Demolition waste (C&D waste) in island regions is predicted to rise with infrastructure development, but its management is challenged by limited landfill capacity, inadequate treatment facilities, and inter-island transport barriers. The purpose of this study is to develop a System Dynamics (SD) model for estimating C&D waste generation and evaluating engineering scenarios for more sustainable waste management in island contexts. The analysis was based on field surveys, waste generation records, infrastructure project statistics, document evaluation, and expert interviews used to validate contextual assumptions. The model was developed using Causal Loop Diagrams and Stock & Flow Diagrams, and it was expanded with two policy scenarios, namely on-site sorting policy and transportation optimization, both individually and in combination. The findings show that the base model projects a continuous rise in C&D waste through 2034. Scenario testing indicates that on-site sorting can reduce waste growth by up to 41.5%, transportation optimization by up to 44.2%, and the combined scenario by up to 74.8%, while also producing narrower uncertainty bands in sensitivity analysis. The novelty of this study lies in integrating dynamic simulation with island-specific logistical constraints to provide a robust and adaptable decision-support framework for evidence-based C&D waste management and sustainable infrastructure planning in island regions.