This is one in a series of training manuals on subjects related to irrigation, issued in the period from 1985 to 1993.
The papers are intended for use by field assistants in agricultural extension services and irrigation technicians at the village and district levels who want to increase their ability to deal with farm-level irrigation issues.
The papers contain material that is intended to provide support for irrigation training courses and to facilitate their conduct. Thus, taken together, they do not present a complete course in themselves, but instructors may find it helpful to use those papers or sections that are relevant to the specific irrigation conditions under discussion. The material may also be useful to individual students who want to review a particular subject without a teacher.
Following an introductory discussion of various aspects of irrigation in the first paper, subsequent subjects discussed are:
- topographic surveying
- crop water needs
- irrigation scheduling
- irrigation methods
- scheme irrigation water needs and supply.
In addition, the following four subjects will be discussed in future editions:
- canals
- structures
- drainage
- scheme irrigation management
At this stage, all the papers are marked provisional because experience with the preparation of irrigation material for use at the village level is limited. After a trial period of a few years, once enough time has elapsed to evaluate the information and the methods outlined in the draft papers, a definitive version of the series can be issued.
For further information and any comments you may wish to make please write to:
Water Resources, Development and Management Service
Land and Water Development Division
FAO
Via delle Terme di Caracalla
00100 Rome
Italy
ABOUT THIS PAPER
Scheme irrigation water needs and supply is the sixth in a series of training manuals on irrigation. The manual describes various kinds of water sources for irrigation and discusses, in short, factors affecting the availability of water for irrigation as well as methods of tapping water. This manual also provides information on how to estimate the irrigation need of a scheme. First, an approximate method for a rough determination of the scheme irrigation water need is given. After an introduction of cropping systems, a more accurate method of calculating the scheme irrigation need is explained. How to determine the scheme irrigation need for a rice-based cropping pattern is also discussed. Finally, the manual discusses how to match the calculated scheme irrigation need with the available supply of irrigation water.
ACKNOWLEDGEMENTS
Much appreciation is expressed to the various specialists in irrigation water management for their valuable comments and suggestions: Messrs. W. Genet, M. Jurriëns, M. Kay, M. Smith, J. Sagardoy and P. van Steekelenburg. A special note of gratitude is expressed to Ms. A. Pulver for editing the text, and Ms. C.D. Smith Redfern for typing, correcting and advising on the layout of the manual.
