In this third edition, the scope of the book is defined to provide source material in the form of a Text book that would meet all the requirements of the undergraduate course and most of the requirements of a post graduate course in Open channel hydraulics as taught in Indian universities. Certain topics have been elaborated and certain portions deleted, more solved examples thus overall making the content much more suitable to today's requirements. Key Features: Meets all the requirements of the undergraduate course and most of the requirements of a post graduate course in Open Channel Hydraulics as taught in an Indian university. The contents of the book, which cover essentially all the important basic areas of open channel flow, are presented in simple, lucid style. The book incorporates revision, an updation of the text with the inclusion of additional topics and some worked-out examples. This edition has detailed/improved coverage on Flow through culverts Discharge estimation in Compound channels Scour at bridge constrictions Section 10.6 which deals with Negative surges in rapidly varied unsteady flow Section 5.7.4 dealing with Backwater curves in natural channels The book is useful for both undergraduate and postgraduate students taking a course in Flow in Open Channels as well as for students appearing in AMIE examinations. Candidates taking Competitive examinations like Central Engineering Services examinations and Central Civil Services examinations will find this book useful in their preparations related to the topic of Water resources engineering. Practicing engineers in the domain of water resources engineering will find this book a useful reference source.