A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development

Thesis (M.Eng.) - Asian Institute of Technology, 1989

A study has been made to evaluate the effect of spatial variability of soil properties o n the design of level b order method of irrigation. Variabilities of Infiltration characteristics and bulk density have been expressed by statistical approach u sing normal and lognormal frequency distributions . Th e study describes a procedure for designing level border irrigation method, using Soil Conservation Service, USDA approach . Water front advance rate predicted by SCS volume balance model for minimum, mean, and maximum infiltration has been compared with the observed advance rate curve. Opportunity time for level border has been plotted for four different stream sizes and compared with the observed opportunity time. Effect of observed variable Infiltration an d bulk density h as been evaluated on application efficiency a nd depth of water infiltrated . The variability of infiltration has been incorporated to calculate the mean and variance of depth infiltrated using variance technique for the evaluation of level border irrigation.