Dagan’s method as well as Kirkham’s one belong to the group of methods for drain spacing determination in steady state water flow conditions. Both methods are based on the assumption that drainage spacing (L) is linear function of water table depth and drainage discharge (h/q). The only difference can be distinguished in the values of coefficients. To dry out eugley type of soil, drain spacing is better determined by Dagan’s method in all treatments, as compared with Kirkham’s one. Advantage of this method is especially marked on the drainage system with narrower drain spacing.