The Role of Estuarine Antecedent Geology in Shaping Marine Geohazards and Storm Surge Infrastructure: A Comparison of the Dutch Maeslant Barrier and the Proposed Bolivar Gate System in Galveston Bay (USA)

This study examines how antecedent geology influences soil mechanics and consolidation in estuarine subsurface deposits, highlighting its potential as a marine geohazard in the context of large infrastructure projects. The Bolivar Roads Gate System is a proposed surge barrier extending across Bolivar Road, which is the mouth of Galveston Bay, to mitigate risks associated with increased storm surges and rising sea levels under a changing climate. Inspired by the Dutch Maeslant Barrier, this study investigates subsurface responses to such large structures, focusing on settlement and consolidation dynamics using existing borehole data and simplified one-dimensional soil calculations. Findings reveal that the saturated clays and cohesive soils at the Bolivar Roads site are prone to settlement rates exceeding those at the Dutch site by over 100-fold, driven by differences in geotechnical properties. Such elevated subsidence could disrupt the stability and operational integrity of the proposed Bolivar Roads navigational structure, potentially affecting land-sea interactions and storm surge protection efficacy. These changes underscore the need for adaptive management strategies, to mitigate differential settlement and ensure long-term functionality. This study contributes to understanding how engineered coastal management solutions interact with dynamic coastal processes, providing insights into sustainable infrastructure in the Anthropocene.