Evaluación de sostenibilidad de la microcuenca de Tona mediante la cuantificación de su huella hídrica

Abstract

Sustainability in water use has become in one of the main priorities in water management for the territorial entities. This is why Arjen Hoekstra [1] defined the water footprint methodology to calculate the amount of water consumed in a given area, as well as the sustainability of said consumption. In turn, the Tona River micro-basin is one of the main water sources that supplies the city of Bucaramanga and its metropolitan area, as well as agricultural production areas. Due to the above, the present investigation evaluated the sustainability of the Tona micro-basin from the measurement of the Water Footprint indicators on the agricultural sector. According to this purpose, two years of study were established, being 2017 and 2020 classified as dry and humid respectively to analyze the variation of water consumption in different climatic conditions. From these years, the monthly water balance indicator was first determined, establishing that the area presents stability and excess during most of the year. Subsequently, a rainfall runoff model was built to estimate the water supply of the study years. Then, using the Hoekstra methodology, the blue, green and gray water footprint and the consumption per ton and at the monthly level of agricultural activities were calculated, finding that the products with the highest consumption were avocado, onion, potato and coffee at the agricultural level. With the water footprint data, consumption was compared with supply to find the hotspots at a temporal level, defining that the summer seasons or those with less rainfall are those that presented a lower degree of sustainability. Finally, with the analysis of the results of water supply and consumption, as well as the identification of environmental hotspots, it was possible to determine the sustainability of the studied area.