The calculation of surface runoff in distributed models may be carried out by the kinematic wave equation (complemented with an infiltration equation). When analyzing an element the use of this equation requires knowledge of the input coming from the neighboring upstream element(s). For this reason, an ordered list termed `kinematic cascade' here, which meets the condition that for any element in it, its upstream neighbors precede that element, should be defined prior to runoff calculations. The procedures needed to find the kinematic cascade, as well as the data structures defining the watershed model, are described. New algorithms to find this cascade for triangular irregular networks (TIN), as well as for regular grid networks (RGN), have been developed. Computer codes were written and tested for both types of watershed models. The main advantage of the proposed new algorithm, as compared to those in use, is that the resulting computer code is very simple, short and easy to implement in any computer language. Also a new way to treat a RGN model as a special case of TIN model is presented. This allows transferring the experience obtained in TIN to RGN models.