Improvement on the Performance of Canal Network and Method of on-Farm Water Application Systems
This paper presents the required improvement on the performance of canal network and method of on-farm water application systems at Tunga-Kawo irrigation scheme, Wushishi, Niger state. The problems of poor delivery of water to the farmland were identified to include erosion of canal embarkment, lack of water regulating structures along the secondary canals and some parts of the irrigable farmland are not leveled thereby making the farmland higher than the canal full supply level. The suggested solution include the alignment of the affected part of the secondary canal, the use of check gates structures for controlling the water level, modification of the longitudinal slope(s) of the main canal and that of the secondary canals to increase the canal conveyance capacity. The use of siphon tubes is also suggested for lifting water from the distributary channels to the irrigating farmland to minimize water loss to percolation. The uncontrolled flooding method of irrigation in use, leads to wastage of water. The pounding basin irrigation method is suggested for rice cultivation on the farm and the irrigation schedule was established to be six days.
JARD Vol. 3 2004: pp. 7-20