Most of the landscape and hydrological modelling are undertaken for unregulated catchments. For water resources planning and management, it is important to understand and model the regulated rivers, where hydrology is heavily influenced by water infrastructures and management rules (reservoirs, weirs, water withdrawal for irrigation and urban water use) instead of climate and catchment physical characteristics alone. This session focusses on development and applications of river system models for water accounting, planning, management and forecasting including any innovative modelling approaches in process representation, calibration, integration with landscape and landcover models.