Determinación de escorrentía superficial y calidad de agua en la cuenca de abastecimiento de la parroquia de Aloasí

Abstract

This research was developed in the Rio Negro watershed that belongs to the parish of Aloasí in the canton of Mejía, located in the province of Pichincha. The experimental design consists of presenting the general parameters of the basin: dissolved oxygen, pH, temperature, turbidity, BOD5, COD, phosphates, nitrates, dissolved solids and fecal coliforms, as well as identifying the water quality indexes in the upper, half and lower zones of the Rio Negro basin. A socioeconomic study was conducted by means of surveys; it was observed that the communities of Barrios Umbría and San Roque lack knowledge about water management in the sector according to the questions asked in the survey. For the water quality analysis, several physical, chemical and biological parameters were taken into account, resulting in a water quality index range of 74,4 a 75,93 units, indicating good water quality for this parish. The ArcGIS 10.5 program was used to calculate the area, perimeter, length of the watershed, length of the main channel, length and width of the watershed, maximum height, minimum height and altitudinal gradient. A model was generated to obtain water drainage. The shape parameters, relief parameters and hypsometric curve showed that this basin is in an intermediate stage, i.e. in the equilibrium phase between maturity and youth, parameters of the drainage network in which the water network corresponding to the basin was determined to be of order three, and the drainage density is 0.32 Km/Km². According to the calculations, the magnitude of surface runoff in the study basin yielded a value of 618.09 mm per year, which is due to the fact that its runoff coefficient is around 0.5 mm and represents an average water retention rate for this basin.