Abstract. In the last decade, agent-based modelling (ABM) became a popular modelling technique in social sciences, medicine, biology and ecology. ABM was designed to simulate systems that are highly dynamic and sensitive to small variations in their composition and their state. As hydrological systems, and natural systems in general, often show dynamic and nonlinear behaviour, ABM can be an appropriate way to model these systems. Nevertheless, only few studies have utilized ABM method for process-based modelling in hydrology. The percolation of water through the unsaturated soil is highly responsive to the current state of the soil system, small variations in composition lead to major changes in the transport system. Hence, we present a new approach for modelling the movement of water through a soil column: autonomous water agents that transport water through the soil while interacting with their environment as well as with other agents under physical laws.