The geometry and hydrological response of a watershed is determined by a combination of precipitation, plant cover and soil resistance to erosion, with rock type being a determining variable. Hydrological studies demand important computational resources, in time and personnel that limit its development. However, for basins with similar geology, whether igneous, metamorphic or sedimentary, it is possible to express the morphometry from mathematical relations that depend on simple metrics such as the length of the riverbed and allow establishing the area, perimeter, shape factor and slope of the basin.