GCRF_NF332 Ongoing impacts from the surge in sand mining during COVID-19: Enhanced river bank erosion hazard and risk in Vietnam's Mekong delta

点击翻译按钮获取中文摘要

SE Asia's CV19 economic recovery plan is heavily reliant on an expanded construction industry, creating high demand for sand across the region. Sand is routinely mined from large rivers and is normally subject to regulation because, if it is removed more rapidly than it is replaced by river flows, it can trigger adverse socio-environmental impacts that hinder development. These include bank erosion - threatening homes and infrastructure - while over-deepened delta channels are also prone to saltwater intrusion. The Mekong delta is already experiencing these problems, but the issue highlighted here is that the CV19 'lockdown' - and potentially the recovery - has led to an upsurge in unregulated sand mining due to limitations in governance capacity. This proposal will spatially quantify this activity and predict the extent to which it will further stimulate bank erosion in the forthcoming monsoon season (when banks become saturated) and subsequent dry season (bank collapse is usually triggered during flow recession). Changes in exposed population as a result of internal migration pre- and post lockdown will also be estimated using expert knowledge verified with traffic volume changes, along with an assessment of exposed socio-economic assets (e.g., roads, schools), to establish changing spatial patterns of hazard, vulnerability and risk. This work is urgent because of concerns that CV19 related mining has primed the system for severe erosion during the impending flood season. The results will guide remediation efforts and aid efforts to promote stronger regulation of sand mining, both post CV19 and for any future disrupting events (including, but not limited to, pandemics) that could potentially stimulate an upsurge in illegal mining.