In Singapore, construction-phase monitoring tests marine EIA predictions at full scale. This paper shows how its outcomes refine assumptions, scenarios and tolerance limits in future EIAs.
Singapore has undertaken and continues to undertake multiple major reclamation and port developments, including Tuas View Extension, Tuas Port and Long Island. The EIAs for these rely heavily on numerical models: hydrodynamic, sediment plume, morphology and water quality models predict impacts on corals, seagrass, intakes and other receptors (including cross-border receptors), and underpin project-specific Environmental Quality Objectives (EQOs). Yet the reliability of each prediction depends on assumptions about sediment properties, spill rates, construction methods and receptor sensitivity. Environmental Monitoring and Management Plans (EMMPs) combining hindcast modelling and detailed monitoring test these assumptions at full scale during construction. Drawing on more than two decades of DHI EIA and EMMP experience in Singapore, this paper examines how EMMP outcomes are fed forward to improve subsequent EIAs. Examples include using measured sediment characteristics and plume behaviour to develop and refine EIA sediment spill rate assumptions; developing more realistic scenarios based on lessons from actual construction methods and sequencing used in previous projects; and using habitat surveys, online sensor records and hindcast model results to validate or revise tolerance limits. The paper discusses what has improved in successive EIAs, what remains uncertain, which elements can transfer to other countries, and the data sharing and regulatory conditions needed to close the 'ultimate feedback loop' from prediction to performance and back to better prediction.
Matt Jury is Project Director, Marine & Coastal at DHI Singapore, with 30+ years in environmental consulting, leading marine EIAs/EMMPs across Southeast Asia, Australia and the Middle East.