Diseño de un sistema de humedales artificiales para la recuperación del arroyo Río Puerta Grande CDMX utilizando parámetros hidrológicos, hidrodinámicos, fisicoquímicos, químicos y biológicos
Authors:   , Espejo Montes Fátima de los Ángeles 
Published: January 2025

The environment pollution has caused damage and this has led to problems, such as the degradation of bodies of water, which is the case in the Río Puerta Grande stream located to the south west of Mexico City, which receives residual discharges, so the objective of this project was designing a treatment system with macrophyte plants. To achieve this, several research stages had to be carried out. The first stage consisted in sampling seven sites along the stream, where several physical-chemical and biological parameters were determined to understand the water quality in more detail. Regarding the analytical results, considering the NOM-001-SEMARNAT-2021 standard, parameters such as total suspended solids, fecal coliforms and mainly BOD and COD, did not comply with the regulations. Through in situ and ex situ analyzes of water quality considering the Water Quality Index (WQI's) with the NSF, Montoya and León models, the evaluation of the stream water was respectively "Very contaminated" and "Very bad" in both periods. On the other hand, it was necessary to know the hydrological stream behavior in the Tarango micro-basin to determine the base runoff of sanitary discharges and direct runoff due to rain. From the data obtained of the physical, chemical and biological parameters, they were modeled with ArcGIS software to obtain interpolation maps, in order to interpret the areas with the highest concentration of each parameter in the two seasons, the red color represents the higher concentrations and the blue one the lower ones, this was important mainly for DO, BOD, COD and fecal coliforms, since they are the parameters that will be considered as contaminants in this stream. To calculate direct runoff, the first step consisted of using the Thiessen polygon method; the areas of influence of the neighboring stations were obtained based on those that have records from other years, since the reference Tarango, does not contain complete data for the study. The adjusted rainfall was determined with the Probability Distribution Functions (PDF), where the Log Normal was the one that presented the best fit. In this work it has been important to determine through the Langelier indices (Is) the nature of the water in the two seasons, since this index allows to know if there are greater or lesser cations and anions dissolved or related to the material in suspension. The ratio of dissolved and particulate metal ions was obtained, as well as their partition coefficients for the two seasons, which was necessary for modeling. On the other hand, with the hydrodynamic modeling of the water body through the Iber software and the variables speed, depth, Froude number and also considering the modeling of the water quality of the channel, it was possible to determine the values of the different physical magnitudes, chemical and biological parameters in each of the sites selected along the channel. Regarding the experimental part of the prototype design, is important to conclude that the hydrophyte plant Eichhornia crassipes was the one that gave the best removal, for this reason it is the one that can be considered for use given its adaptive characteristics, since it does not require much maintenance and Its reproduction is for short periods of time, for which it was proposed as the alternative plant that was used in this work for the final design of the wetland treatment system with which it is intended to eliminate BOD and fecal coliforms contaminants.