By Ugwu, Ifeanyi Ella
The economic importance of agricultural produce and the need to be self-sufficient has brought irrigation technology to the forefront in several parts of the world, including Nigeria. Improving surface irrigation methods is of great importance especially in the light of securing better use of water resources. Irrigation performance assessment, in recent times, has been given the highest priority in irrigation research among other research priorities needed to solve the problems of irrigation development and management in Nigeria. This study was centered on the performance evaluation of a surface irrigation project, the Lower Anambra Irrigation Project (LAIP), at Omor in Anambra state. Four fields cultivated with rice were randomly selected for the study. The soil texture was clay loam with aspect ratio ranging from 0.35 to 0.67 while the surface area was between 216 and 504 m2. The mean soil moisture, volumetric moisture, bulk density, field capacity, permanent wilting point and the total available water taken at different depth profiles of 0 - 15, 15 - 30 and 30 - 45 cm were 23.4 %, 28.6 %, 1.28 g/cm3, 35.26 % v/v, 21.77 % v/v, and 2.84 mm/m, respectively. The soil infiltration rate after 160 min was 0.12 mm/min, while the maximum cumulative infiltration was 62 mm at 220 min. The mean flow rate of the irrigation water flowing into the basins was 168.25 cm3/sec. The mean application efficiency, water requirement efficiency and the distribution uniformity were 67.6, 80.6 and 63.0 %, respectively.