hydrology and river mechanics. The physical modeling of rivers followed by prototype
verification, mathematical modeling of river response followed by field verification,
mathematical modeling of water and sediment yield from small watersheds, and studies of
unsteady sediment transport are areas in which significant advances can be made.
A primary research need is the collection of field data on the flow variables and depth of scour
at bridges, embankments and at river control structures. Studies are needed to better define
the planform of rivers and their response to changing flow conditions. In addition, laboratory
and field studies are needed to improve the equations for estimating total scour at piers and
Operational research on decision making, considering cost and risk criteria to determine the
hydrologic and hydraulic design of highway structures and project alternatives, is another
pressing research area. Insufficient data is frequently a problem of river mechanics analysis.
A comprehensive study on information theory is needed to cope with such difficulties.
Finally the results of these efforts must be presented in such a form that it can be easily taught
and easily put to practical use.
As pointed out in Section 1.6.1, engineering training is often inadequate in relation to
understanding the dynamics of rivers. Better ways to train engineers and to disseminate
existing knowledge in this important area need to be considered. The curriculum of university
education made available to engineers should be improved, particularly at the undergraduate
level. At the very minimum, such a curriculum should strive to introduce concepts of fluvial
geomorphology, river hydraulics, erosion and sedimentation, environmental considerations and
Formal training should be supported with field trips and laboratory demonstrations. Laboratory
demonstrations are an inexpensive method of quickly and effectively teaching the
fundamentals of river mechanics and illustrating the behavior of structures. These
demonstrations should be followed by field trips to illustrate similarities and differences
between phenomena in the laboratory and in the field.
1.7 OVERVIEW OF MANUAL CONTENTS
In the following sections a brief overview of each chapter will be given.
1.7.1 Chapter 2 - Open Channel Flow
This chapter describes the fundamentals of rigid boundary open channel flow. In open
channel flow, the water surface is not confined; surface configuration, flow pattern and
pressure distribution within the flow depend on gravity. In rigid boundary open channel flow,
no deformation of the bed and banks is considered. Mobile boundary hydraulics refers to
flow, which can generate deformation of the boundary through scour and fill. Mobile