Management of surface water systems, including rivers, reservoirs, lakes, wetlands, and estuaries, requires technical tools that must be based on physical, chemical, biological, and social sciences. Some of these tools entail numerical hydrodynamic and water quality models, made possible these days by ever-increasing computing prowess. This book attempts to describe physical, chemical, and biological concepts underlying these models. To that end, the book aims at providing an integrated treatment of hydrodynamics, sediment transport and processes, toxic fate and transport, water quality, and eutrophication in surface water systems. The emphasis in the book is on principles, basic processes, mathematical descriptions, and practical applications via case studies. Justifiably, it avoids long mathematical derivations. The book also presents case studies to illustrate the implementation of basic concepts and theories and technical approaches based thereon into mathematical models, as well as application of these models to address practical environmental and water resources problems.
The subject matter of the book is logically divided into 10 chapters and three appendices. Chapter 1 provides an overview and develops the context for the material to be described in the book. Chapter 2 provides basic concepts and principles of hydrodynamics. Starting with a description of hydrodynamic processes, it goes on to discuss governing equations and their approximations in one-dimensional, two-dimensional and three-dimensional Cartesian coordinates. Equations in curvilinear coordinates are presented next, followed by a discussion of initial and boundary conditions. Then temperature and heat fluxes are presented. This discussion is integrated in the following section on hydrodynamic modeling, with case studies of Lake Ockeechobee and the St. Lucie Estuary and Indian River Lagoon. These case studies are very helpful to understand hydrodynamics and its practical application.
Sediment transport is discussed in Chapter 3. Providing an overview, including sediment properties, problems associated with sediment, and sediment processes, it discusses sediment transport equations for both cohesive and noncohesive sediments, as well as wind waves and their impact on sediment transport. The chapter presents two case studies one on wind wave modeling and the other on sediment transport modeling in Lake Ockeechobee. The third case study is on sediment transport modeling for Blackstone River. These case studies clearly show how to set up a model, define initial and boundary conditions, prepare data for model calibration and validation, and describe difficulties that may be encountered in running the model. The chapter is a comprehensive summary of sedimentation engineering and its application in the real world.
Chapter 4 deals with pathogens and toxics—a very important topic, especially in light of the way we have been treating natural systems. It discusses pathogens (bacteria, viruses, and protozoa), pathogen indicators, and the processes affecting pathogens. Then, toxic substances and their fate and transport processes are discussed. The chapter is concluded with a discussion of contaminant modeling, illustrated with a case study of the St. Lucie Estuary and Indian River Lagoon, as well as a case study of Rockford Lake.
Water quality and eutrophication constitute the subject matter of Chapter 5. It is a comprehensive chapter. Beginning with an overview of eutrophication, algae, nutrients, dissolved oxygen, and governing equations for water quality processes, it discusses algae-related processes, organic carbon, phosphorus, nitrogen, dissolved oxygen, sediment fluxes, and submerged vegetation. The chapter concludes with a treatment of water quality modeling, illustrated with a case study of Lake Ockeechobee and another case study of the St. Lucie Estuary and Indian River Lagoon. Both case studies are highly informative and useful.
Chapter 6 deals with external sources and TMDL—a topic of great current interest these days. Beginning with a discussion of point and nonpoint sources of pollution, it provides a coverage of atmospheric deposition, wetlands and groundwater, and watershed processes and TMDL development. Mathematical modeling and statistical analyses are presented in Chapter 7. The discussion of mathematical models includes numerical models, model selection, and spatial and temporal resolution. Statistical analyses include statistics for model performance evaluation, correlation and regression, spectral analysis, empirical orthogonal function, and an EOF study. The chapter is concluded with a discussion of model calibration and verification.
Rivers are dealt with in Chapter 8. River characteristics, hydrodynamic processes, and sediment and water quality processes constitute the subject matter of the chapter. River modeling, illustrated by two case studies—one on Blackstone River and the other on Susquehanna River—concludes this chapter. Chapter 9 discusses characteristics of lakes and reservoirs, hydrodynamic processes, and sediment and water quality processes in lakes. The chapter is concluded with a discussion of two case studies—one on Lake Tenkiller and the other on Lake Okeechobee. Chapter 10, the last chapter, treats estuaries and coastal waters. It discusses tidal processes, hydrodynamic processes in estuaries, and sediment and water quality processes in estuaries. Two case studies dealing with estuarine and coastal modeling—one on Morro Bay and the other on the St. Lucie Estuary and Indian River Lagoon—conclude the chapter. The book is appended with environmental fluid dynamic code in Appendix A, conversion factors in Appendix B, and contents and electronic files in Appendix C.
One of the major strengths of the book is the incorporation of case studies in each chapter, which integrate concepts and principles discussed in the chapter and illustrate their application in the real world. This is extremely useful for teaching a course on water quality modeling. The book would be well suited for a senior undergraduate course or a beginning graduate course on water quality modeling, except that there are no solved examples or end-of-chapter problems, which are extremely helpful to both the student and the instructor. Although part of Chapter 7 deals with statistical analysis, statistical concepts are not clearly integrated with other chapters. On the whole, the topics are well organized, the prose is easy to read and understand, the style is lucid, and there is a wealth of information reflecting the knowledge and experience of the author. The book will also be useful to practicing water and environmental engineers.