Determination of Conveyance Loss through Earthen Channel by Cutthroat Flume

摘要

The conveyance efficiency in irrigation projects is poor due to seepage, percolation, cracking, and damaging of the earth channel. Seepage loss in irrigation water conveyance system is very significant, as it forms the major portion of the water loss in the irrigation system. The purpose of this study was to determine the conveyance losses of irrigation water through earthen channel. A 50ft long and straight earthen channel was selected for this purpose. It was modified by excavation and compaction and also by maintaining suitable bed slope and side slopes. In this experiment discharge was measured by Inflow-Outflow method using cut-throat flumes. It can be seen from the results that conveyance losses were found to be 40.01%, 35.42%, 32.81% and 4% under natural condition, compacting the sides and bottom, using lining material of cow dung and rice husk mixture ratio 1:1 and polythene sheet, respectively. The results also indicated that lining material reduced conveyance loss to a great extent followed by compaction and natural conditions. It may be inferred that the mixture of cow dung and rice husk could be used as lining material because it is easily available, low cost and even unskilled labor can make it. Finally it could be used for reducing water losses through earthen channel.