The history of hydrological studies on the Mekong floodplains – from colonial experiments to computational models

Understanding the complex hydrology of the Mekong floodplains, which underlies the region's agricultural productivity and rich fisheries, has historically been a key interest of political authorities, engineers, and local communities, from the earliest day of the Khmer Empire in the 9 th century to international development efforts after the Vietnam War. This paper outlines how the hydrology of the Mekong floodplains has been understood over time, from the detailed reports and projects developed by engineers during the French colonial period in the late 19 th century to the first computational models, written in the 1960s on punch-cards and in Fortran. It also provides an overview of how public works projects developed on the basis of this understanding have shaped the current landscape and hydrology of the Mekong floodplains. In particular, it analyses the motivations behind the historical hydrological studies conducted over the centuries, and how their motivations influenced their methodologies and results.