We present a real-time method to simulate and render the turbulent flow and splash of stream water over irregular terrain and with dynamic rigid objects. In order to achieve real-time frame rates, we adopt a GPU-based particle system to perform the simulation, which can simulate interaction between water and dynamic rigid object in real time. We use 2D metaballs with billboards to represent the 3D water surface. Our billboard rendering method does not possess the traditional clipping artifact. Although our proposed method is not a direct physical simulation, the results are empirically plausible and efficient, and especially suitable for interactive graphics application such as computer games.