Review of Fluvial Processes by M. Selim Yalin and A. M. Ferreira da Silva

The importance of fluvial processes has increased in recent years as ever-growing numbers of humans attempt to interact harmoniously with their natural environment. Traditional concerns such as flooding and erosion continue to remind us of nature’s power. More contemporary concerns such as contaminated sediment remind us of our responsibility of stewardship. A book illuminating fluvial processes, such as the one under review, is therefore welcomed to aid us in our understanding of the problems and, perhaps, to inspire us to solutions. As stated in the preface ‘‘This monograph concerns the understanding and quantitative formulation of fluvial processes and the associated alluvial forms. It is designed for researchers and graduate students of hydraulic engineering, water resources, and the related branches of earth sciences. However, it may have some appeal to practicing professionals as well.’’ It thus requires some background knowledge of mathematics, fluid mechanics, hydraulics, and sediment transport prior to indulging into its depths, although the first chapter reviews, in a somewhat cursory manner, the topics of sediment transport and turbulent flow. As to scope, the work addresses those channels of a practical nature, i.e., turbulent, subcritical, steady flow in wide channels with cohesionless material. The chapter on the geometry and mechanics of meandering streams is for the simplified conditions of regular sinusoidal wave-like patterns and with rigid banks. The topics covered are few, but focused. Of the wide variety of topics in fluvial processes the authors focus on bed forms, resistance, regime theory, channel geometry, meandering, and braiding. Fig. 1 shows an example of one of these topics, namely, bedforms. The book is for the graduate level. The equations are developed and formulated with some rigor. The work of others is cited, but the authors’ use of the approach of comparing the scales of turbulence to the scales of sediment forms is highlighted throughout. A heavy dependence on dimensional analysis is also evident throughout the work. The text contains a thorough treatment of regime theory, which the authors state may derive from the minimization of the energy principle. In addition, there is an extensive chapter on why regime theory works, with postulates about which physical processes influence the river in approaching some equilibrium state. Much of the present work appears similar to the senior author’s previous work entitled River Mechanics. There are a few additional subjects addressed, such as the formation of regime channels and meandering-related computations, but not many. In that respect, perhaps a more appropriate title for the present work could have been River Mechanics, 2nd edition. Several other features of the text are commendable. Algorithms are suggested for some computations and a CD-ROM containing software for the computation of resistance is included. In addition, there are examples in the text, although very few. The examples do use units in the given quantities and in the final answers but not in the intermediate steps. Perhaps at a graduate level it may be expected that the student should be able to navigate around this barrier, but its inclusion would be helpful. It is also helpful that the references for each chapter are included at the chapter’s conclusion and handily divided into those of general interest to the chapter and then also into specific subject categories of that chapter. As far as problems to be worked out by the reader, there are a fair number. These are helpful in and of themselves but the problems use real data and, therefore, are even more valuable for the reader to get a feel for ranges of parameter values often encountered. In addition, there is a solution manual available for an additional Euro 30. There are, however, some constructive suggestions that can be made. These include the need for captions on the figures. No captions are given on any of the figures throughout the text, and, although the figures are referred to in the text, it would be very helpful to know what you are looking at and its significance to the discussion at hand. In addition, there is very little on the very important fluvial processes of open-channel flow, sediment properties, scour, river training, or mixing. An inclusion of these topics intertwined with the existing topics would have made this text more complete. Without any mention of how the fluvial processes treated in the text can be used to aid in our living with the river in a sustainable fashion, the text is less practical. The text is a useful one that should be included in any library on fluvial hydraulics.