IWRM modeling aims at representing interactions between humans and their environment (Badham et al. 2019), which can involve hydrological, surface-hydraulic, and groundwater models. Semi-distributed models implementing a simplified hydraulic propagation between sub-catchments are often used as IWRM model (Ficchi et al. 2014, Dorchies et al. 2016) because of the good trade-off they offer between simplification and result relevancy. The R-package airGR (Coron et al., 2017, 2020) is widely used in the R language hydrology community and its recent development with semi-distributive (see Abstract EGU21-1371) capabilities allows to use it for IWRM modeling. The R-package airGRiwrm has been developed for multiple purposes linked to IWRM. First, it proposes a simplified network description for building semi-distributed models containing several sub-basins with diverse connections, which greatly simplifies the calibration and modeling steps. Then, it allows to easily integrate predefined flows (feedforward control) into the model, namely local flow injections or withdrawals. Finally, it integrates controllers that apply user-defined decision algorithms given model outputs during simulation (feedback control). The controllers allows for example to apply withdrawal restriction in case of drought, or to simulate a reservoir behaviour with complex management rules. In this presentation, we will introduce the airGRiwrm possibilities and we will demonstrate its use on the case of the Seine River basin in France.