This report describes flow-control methods for reducing ice problems in rivers. Objectives include reducing ice interference with winter hydroelectric production and navigation, ice jam flood mitigation, as well as ensuring minimum winter flows for fish and water supply. The winter season is divided into three periods. During early winter, the main objective of flow control is to promote the rapid formation of a smooth, stable ice cover. For the midwinter period, the aim of the river regulation is to maintain an intact ice cover and avoid premature ice breakup. During the final winter period, the goal is to minimize adverse effects of ice breakup. Examples illustrate the methods and objectives, emphasizing innovative approaches. Available flow regulation planning tools are described and valuable research directions identified.

This book exposes practitioners and students to the theory and application of river and lake ice processes to gain a better understanding of these processes for modelling and forecasting. It focuses on the following processes of the surface water ice: freeze-up, ice cover thickening, ice cover breakup and ice jamming. The reader will receive a fundamental understanding of the physical processes of each component and how they are applied in monitoring and modelling ice covers during the winter season and forecasting ice floods. Exercises accompany each component to reinforce the theoretical principles learned. These exercises will also expose the reader to different tools to process data, such a space-borne remote sensing imagery for ice cover classification. A thread supporting numerical modelling of river ice and lake ice processes runs through the book.