Chapra has organized this user-friendly text in a lecture format to engage students who want to assimilate information in manageable units. Comical examples and literary quotes interspersed throughout the text motivate readers to view the material in the proper context. Coverage includes the necessary issues of surface water modeling, such as reaction kinetics, mixed versus nonmixed systems, and a variety of possible contaminants and indicators; environments commonly encountered in water-quality modeling; model calibration, verification, and sensitivity analysis; and major water-quality-modeling problems.
Most formulations and techniques are accompanied by an explanation of their origin and/or theoretical basis. Although the book points toward numerical, computer-oriented applications, strong use is made of analytical solutions. In addition, the text includes extensive worked examples that relate theory to applications and illustrate the mechanics and subtleties of the computations.
Advection, dispersion and concentrated sources or sinks of contaminants lead to the formulation of the fundamental differential equation of pollutant transport. Its integration, according to appropriate initial and boundary conditions and with the knowledge of the velocity field, allows for pollutant behaviour to be assessed in the entire water body. An analytical integration is convenient only in one-dimensional approach with considerable simplification. Integration in the numerical field is useful for taking into account particular aspects of water body and pollutants.
To ensure their reliability, the models require accurate calibration and validation, based on proper data, taken from direct measurements. In addition, sensitivity and uncertainty analysis are also of utmost importance.
All the above items are discussed in detail in the 21 chapters of the book, which is written in a didactic form for professionals and students.