Floods can cause some damage in urban, industrial and agricultural areas along rivers. In order to prevent flood damage, some structures are built along many rivers. For desing of these structures, it is very important to estimate floods as well as the effects of stream channels on floods. Flood routing methods can be used to calculate floods. In this study, the simplified dynamic model has been applied for flood in a open channel. The solution of these equations has been done by using implicit four-point scheme. The results obtained by the solutions are discussed.