Irrigation System Case Study

CHAPTER 1

Introduction

1.1 General

Irrigation is a method to reach the sustainable agriculture as it supplies deficit water to the crops where rainfall cannot fulfil the crop water requirement. An irrigation system facilitates by supplying required amount of water at desirable head at proper time and duration to the agriculture fields through a network of canals. And the design, operation and management of these irrigation system play a vital role in keeping the system achieve its aim for sustainable agriculture. Moreover, this can only be achieved when there is adequate, equitable, reliable and efficient irrigation system, however, due to various reasons like sedimentation, it has greatly affect the performance of the irrigation systems.

Under bi-lateral agreement between Nepal and India in 1954, the system was designed and constructed by Government of India from 1964 to 1973 was handed over to Nepal in 1975 after two years of trial operation(Paudel, 2010). The water is withdrawn through a side intake from the left bank of the Koshi River. Koshi is known to be heavy sediment laden river, according to Hooning, 2011, the river carries 59 million m3 of sand

Moreover, the irrigation systems are designed considering steady and uniform flow however, these can barely find in irrigation systems nowadays. The irrigation systems have become more demand driven with frequent change in flow requiring frequent operation of flow control structures. This canal operation leads to unsteady and non-uniform flow which opposes the assumptions made thus these schemes require high maintenance cost because of the unwanted erosion or sedimentation in the