Timeliness and operational convenience For Ranbir canal command area

Abstract

Water distribution systems often have to satisfy many objectives. The canal systems distributing the water through net works of major and minor systems have different design capacities, command areas and lengths requiring different duration of operation. Irrigation scheduling under these conditions especially for rotational water distribution becomes a complex process. The present study based on location and timeliness criteria of canal network emerging from Ratian head works of gravity flow Ranbir canal system of Jammu has been studied. The canal network receive irrigation water from head works on 14 days rotation basis with 7 days turn for D-10 and D-10A. The canal network has 13 branches having command area of 13375 ha of farmers land within famous basmati bowl of Jammu province. The results in the study area related to timeliness criteria for all the 13 canals of the study area for rice crop indicate that during nursery period for 23 days there are 1000 to 1500% times excess water, during field bed preparation for 7 days there is 50 to 80% times deficit water, during planting to pinnacle initiation for 70 days there is 20 to 40% times excess water, during pinnacle initiation to flowering for 22 days there is 60 to 80% times deficit water and followed by flowering to maturity stage there is marginal excess water to the extent of 10 to 20% within command areas of both distributary canal. This clearly indicates that two stages of water demand during field bed preparation and pinnacle initiation to flowering periods are critical deficit periods within the command areas of the study area. On, the contrary rest of the periods have excess supplies, which need to be restricted by sluice gate operation to save water and the command area from drainage problems. The two deficit water periods indicated above may be responsible for stagnant productivity levels of basmati – rice ranging between 19-20 qtls /ha within the study area, despite application of recommended quality seed, fertilizer application dose and desired farm power energy level in the study area.