A model to solve the hydraulics of trickle irrigation units is developed in this study.
This model is based on utilizing Newton Raphson technique. The model converts laterals into
equivalent outlets through utilizing a simple power relation between inlet lateral discharge and
hydraulic head. This relation is obtained through least squares analysis between inlet lateral
discharge and hydraulic head. This study showed that this relation with only two coefficients
is sufficient to describe the relation between inlet lateral discharge and hydraulic head. Based
on this relation, the model converts manifold lines into equivalent laterals and solves their
hydraulics by Newton Raphson technique. After that solution, the model evaluates trickle ir-
rigation units by estimating statistical uniformity and Christiansen uniformity coefficients and
checks the solution obtained through forward step method for each lateral. Several numerical
examples for utilizing the model are presented in this paper.