Sustainable port maintenance: Dredging equipment selection in time-emission trade-offs

• Framework quantifies dredging emissions via energy-use and activity models. • Discrete-event simulation compares TSHD and WID efficiency and emissions. • Event table approach links vessel behavior, scales, and tidal constraints. • Case study at Port of Ramsgate validates emission estimates with real data. • Trade-off analysis reveals a balance between project time and environmental impact. Maintenance dredging in ports and waterways is essential to ensure safe navigation. With increasing regulatory pressure on the maritime sector to reduce exhaust emissions, both dredging contractors and port authorities are seeking effective mitigation strategies. However, accurate emission estimates for maintenance dredging activities are still limited in the literature and often rely on experiential knowledge rather than scientific methodologies. This study suggests a method for estimating emissions and comparing alternative maintenance dredging strategies by quantifying trade-offs between project duration, energy consumption, and emissions. The method integrates vessel characteristics, project specifications, and sediment properties to allow for situation-specific, realistic assessments. A discrete-event simulation is used to evaluate two alternative scenarios, offering insights into the impact of key parameters on vessel selection and overall operational efficiency. The method is demonstrated using a case study of the Port of Ramsgate (UK), where estimated results are compared with real-world data for validation. Finally, the study outlines theoretical and managerial implications and suggests directions for future research.