Java, l'île principale de l'archipel indonésien a vu la construction, depuis les années 1960, de nombreux grands barrages. Leurs rôles sont multiples, passant du contrôle des flux liquides (écrêtage des crues et soutien des étiages) à l'approvisionnement en eau des grandes agglomérations urbaines et des terres agricoles. Ils jouent également le rôle important de fournisseur d'énergie. Depuis leur mise en eau, on assiste à un comblement rapide des réservoirs liés à des taux d'érosion qui figurent parmi les plus élevés du monde. La diminution importante de leur efficacité entraîne par conséquent de nombreuses répercussions néfastes sur le milieu et les sociétés. Les objectifs de cette recherche sont ainsi de déterminer, avec des approches multiples (SIG, télédétection, base de données hydro-climatiques, sondages lacustres...), les taux et les rythmes de remplissage de ces réservoirs, agissant comme indicateurs de l'érosion dans leur bassins-versants respectifs. Il s'agira de mettre en évidence les facteurs principaux influant sur cette forte sédimentation et de mettre en place des outils permettant de venir en aide aux organismes chargés de la gestion des bassins-versants javanais. / Since the Sixties, a large number of dams have been built in the Indonesian archipelago's main island, Java. Their rôle are multiple, going from liquid flows control (flood – peak shaving and low flow support) to water supply of great urban areas and agricultural lands. They also are an important energy supplier. After their watering, a fast filling of the tanks related to rates of erosion that appear among the highest in the world, has been observed. This significant efficiency decrease involves multiple negative impacts on environment and utilities. Through a multiple approach (GIS, remote sensing, hydroclimatic databases, lake surveys...), the objectives of this research are to determine the sedimentary transfer rates and pace within the studied basins, which act as erosion indicators in their respective basins. The key determinants affecting this high sedimentation will be highlighted and a software will be developed with the aim to provide Javanese river basins authorities with new tools.

Between 1961 and 1976 Häi Hung province -- present day Häi Duong and Hung Yên -- lost the equivalent of two entire districts of agricultural land. How could so much land be abandoned under a collectivised agriculture system? And what role did poor water control infrastructure play in creating such a situation?¶ I answer these questions by examining the historical patterns of hydraulic development in northern Vietnam from the beginning of the 19th century until the introduction of the Production Contract system in 1981. Underlying both the French colonial and communist visions of modernity and economic development was a belief that improving agricultural productivity, of which large-scale hydraulic infrastructure was an important component, could catalyse growth in the rural economy, which could then finance industrialisation. I argue throughout this thesis that developing large-scale hydraulic infrastructure in the Red River delta has relied upon the creation of a hydraulic bargain between the state and water users. This is in contrast to Wittfogel's theory of the hydraulic state, insofar as developing hydraulic infrastructure has depended upon the active political and economic participation and support of water users, and not the absolute power of the state. The political economic history of the hydraulic bargain highlights the relative power of peasants to influence the direction of large-scale hydraulic development and, as such, the shape of the Red River delta's wet-rice economy.