Optimal Crop Water Requirement and Irrigation scheduling For The Command Area Under Srisailam Leet Bank Canal (SLBC), A.P. Using Cropwat Software/ M. L. Padmaja Joshi & K. Ramamohan Reddy

In the planning, design and operation of irrigation systems, accurate information on crop water requirements, soil water balances and incidence of rainfall are required in addition to the information on the availability of water, crops and crop areas. It enables to draw water from source according to the needs from time to time for its optimal use. Unfortunately rigorous exercise on the inventory of resource and demands is not made either due to paucity of relevant information or due to the fact that the routine procedures that are in use do not incorporate these details. Thus, the approach more or less remains adhoc resulting in sub-optimal use of available resources. Although advanced methods of farm irrigation scheduling are available in practice, these are not developed based on the soil, crop and climatic factors to guide the project operations for optimal benefits. In the present study, an attempt is made, to use a scientific technique of farm irrigation scheduling to demonstrate its efficacy in predicting the timing and amount of irrigation water at the farm level, which in turn, could guide the releases from the irrigation system to meet these demands and improve its performance. In the present study, crop water requirement of Srisailam Left Bank Canal(SLBC) of A.P and irrigation scheduling calculations are done by using cropwat software. The results of the study focus light on important aspect of irrigation scheduling such as the time of irrigation to utilize the maximum amount of rainfall and draw only the balance quantities of water from the irrigation system at the rates commensurate with the system capacity