Morphometric Characterization Of The Upper Watershed Of The Sauce Grande River, Buenos Aires, Argentina

The upper watershed of the Sauce Grande river supplies water to the hydraulic complex of the dike Paso de las Piedras, which is a precious environmental service for water consumption in Bahia Blanca city. A system of payment for environmental services as a basic strategy for territorial management and local development should be based on the water supply generated by the watershed. Analyzing morphometric and functional characteristics of a watershed through parameters of shape, relief, and drainage is basic for hydrologic modeling in order to establish the movement and capture of rainwater. The aim of this work was to make a morphometric characterization of the upper watershed of Sauce Grande river. The methodology was based on the establishment and analysis of morphometric parameters obtained from digital terrain model and satellite imageries, using a Geographic Information System and spreadsheets. The area of the watershed is of 1502.6 km(2), the axial longitude of 41.6 km, with a mean width of 36.1 km. The shape factor of 0.87 indicates an elongated shape. The Gravellius coefficient of 2.8 indicates an oblong rectangular shape. The river length is 58.34 km with a mean slope of 0.48 %. The drainage density is 0.27 km. km(-2) with a sinuosity coefficient of 1.42. The concentration time is 11.8 hs. The adimensional hypsometric curve corresponds to a watershed with a high level of development. All these parameters contribute to water flow quantification in the watershed.