Fulfilling both "Water and soil conservation" and "Integrated rural development" objectives, hillside reservoirsare very popular components of water and/or rural management strategies. In Central Tunisia, more than 800reservoirs have been built since the 1950s. These have been the subject of an abundant literature by both socialand physical scientists. However, this literature, which is highly segmented and often centred on the technicaland economic assessment of development programs, does not help understand the different logics at work in theappropriation of these technical objects by the different actors involved.To achieve this goal, our research based on a "sociohydrological negotiation", articulates the methods andresearch questions of hydrology and anthropology on a same case study in Central Tunisia. An initial survey ofwater use and management practices around hillside reservoirs in the Merguellil Catchment revealed the widevariety of the infrastructures and the multiple functions they fulfil. These initial observations underpinned theprocess of negotiating an interdisciplinary framework to analyze the social, physical and technical dimensions ofhillside reservoirs.To trace the history of watershed development policies implemented in the Merguellil Catchment, we firstexamined the multiple embedded logics underlying Tunisian hillside reservoir planning. This led to the production of "sociohydrological narratives" for four hillside reservoirs that both combined and enabled us toanalyze the inhabitants' own accounts of their reservoir history. This ethnographical material was then examinedthrough the lense of a "esource making process". Considering the way in which hydraulic objects function in alandscape that is both socio-political and hydrological enabled us to analyze the different aspects of this resourcemaking process, from water valuation to the production of "hydraulic localities".