Kajian Nilai Koefisien Kekasaran Saluran Irigasi Tersier Dengan Metode Chezy dan Manning pada Daerah Irigasi Serbangan Kecamatan Rawang Panca Arga Kabupaten Asahan

Abstract

This tertiary irrigation channel is located in the Serbangan Irrigation Area, Rawang Panca Arga District, Asahan Regency. Water distribution efficiency is influenced by water flow velocity and channel conditions, both of which can be manifested through roughness values or channel constants. This study aims to determine the Manning roughness values and Chezy constants in five tertiary channels with vegetation and channels that have been pruned. The roughness values for the concrete channels are 0.139, 0.145, and 0.14. The roughness values for the earthen channels before vegetation pruning are 0.137 and 0.147. The roughness values for the earthen channels after vegetation pruning are 0.128 and 0.136. The Chezy constant values for the concrete channel are 4.47, 4.5, and 4.48. The Chezy constant values for the earthen channel before vegetation was pruned are 4.88 and 4.56. The Chezy constant values for the earthen channel after vegetation was pruned are 5.22 and 4.95.