Hydrological studies are an important step to complete knowledge of river basins, as well as their association with the areas of water resource development and agricultural development projects in the studied basins. These basins lack the stations to measure runoff, so that they depend on the application of mathematical equations calculating precipitation amounts and characteristics of runoff to determine hydrological budget. In addition, one of the most important and common used ways to estimate runoff (SCS-CN) is beveloped by the U.S. Soil Conservation Authority. It is a method that estimates the volume of direct runoff from the rainstorm.