The purpose of this paper is to use a viability-based approach for giving an operational view of the Institutional Analysis and Development (IAD) framework. The IAD framework was broadly studied by scholars for highlighting the strengths and weaknesses of institutional arrangements in the case of the management of socio-ecological systems (based on natural infrastructure) and of coupled infrastructure systems (based on human-made infrastructure). By nesting this IAD framework within a viability approach, we assess operational tools for policy-makers for helping them in their decision-making process. We illustrate our approach inthe case of an irrigation system for highlighting both the genericity of the current approach and the diversity of the assessed outcomes.
The purpose here is to apply our approach to an irrigation model in Nepal already studied [Cifdaloz, 2010] with an IAD-based framework . For the irrigation model in Nepal, the system is composed of an infrastructure that provide water from the river to the farmer for paddy rice crop. The aim is to keep a sufficient height of water in the field while avoiding flood. As explained in [Cifdaloz, 2010] , the first stage (transplant stage that lasts 9 days) is the most crucial stage and the most sensitive stage to variations in water levels.