Real-time flood forecasting in the middle and lower reaches of the Yangtze River

Using the flood control system in the middle and lower reaches of the Yangtze River as study objects, a numerical model for real-time flood forecasting in the reaches is presented. The model is a further development of the flow and bed-load transport module that is part of a complex flood control system and able to provide information for flood control planning. To accommodate the needs of quickly and accurately forecasting floods and operating control structures in real-time, we propose an iterative scrolling algorithm and calibration techniques based on hydrodynamics. Coupling the numerical model with real-time calibration of hydrological parameters can thus be achieved. A trial operation of the numerical model is conducted during the Yangtze River flooding seasons. The result shows that the numerical model is able to effectively address key issues that arise from executing the real-time calibration of hydrological parameters and from real-time flood forecasting after Yangtze River embankment breached. The result provides the technical support for flood control planning and real-time flood operations. Our results have been used in flood operations for the middle and lower reaches of the Yangtze River.