GENERATING RATING CURVE AND RATING TABLE OF GOLARCHI MINOR

Abstract

Hydrologists must have huge theoretical and practical knowledge of irrigation networks such as rivers, canals, streams, channels, and minors. Because whole irrigation system relies on a gauge and discharges relationship which is essential for controlling floods, water resource management, and hydrologic modeling. The true and consistent figures of flow rate in the irrigation system are important for irrigation water efficiency. Mostly, Hydrologic modeling activities like hydraulic structures, designs, and management of surplus water in canals are subjected to the flow of irrigation water which is derived from the rating curve (RC). The managing of irrigation water in the system must be essential for crop water requirements and estimation of seepage losses. Thus, to fulfill the objectives, field activities (discharge measurement) were conducted in Golarchi minor of the Left-bank area water board. The main target was to calculate real discharge at different gauge levels and to develop a rating curve and rating table for the accurate distribution of irrigation water in the command area. Hence, the discharge was measured with a current meter and the area velocity method was employed for flowing water. The discharge was taken at three different gauges i.e., 1.2ft, 1.34ft, and 1.55ft with the discharge of 51.921cusecs, 55.021cusecs, and 58.197cusecs. Then collected data was exported to MS Excel for manipulation and for developing rating curves. The power equation was developed for Golarchi minor for confirming the different discharges on different gauge heights. The results of the study calculated as 1.1ft gauge to 1.7ft gave discharge 50.383cusecs to 61.009cusecs. It is concluded that the present study suggested that there should have an automatic gauging station to know the real demand for irrigation water in the command area and di-siltation should be done.