Multitemporal Total Coliforms and Escherichia coli Analysis in the Middle Bogotá River Basin, 2007–2019

Currently, one of the main environmental problems that need to be addressed is the pollution inflicted upon different ecosystems by anthropic activities. One example of this problem can be seen in the Bogotá River, a major river in the Cundinamarca department of Columbia and the main water source supplying the Bogotá savannah, which reaches the Colombian capital city. The Bogotá River is highly affected by effluents and wastewater of domestic and industrial origin, among others. These pollutants are generated and accumulated throughout the entire basin, without ever receiving any type of treatment. The pollution levels to which the Bogotá River is subjected can be determined with the calculation of environmental indices, including microbiological contamination indicators such as total coliforms (TC) and fecal coliforms, which include Escherichia coli , Enterobacter, Klebsiella, Serratia, Edwardsiella , and Citrobacter bacteria, living as independent saprophytes. This paper assesses the quality of the water in the Bogotá River, using microbiological indicators and data provided by the Regional Autonomous Corporation (CAR) of Cundinamarca to assess water samples, extracted based on the climatic bimodality exhibited in the basin in dry and wet seasons. The scope of this study was limited to the 35 monitoring Regional Autonomous Corporation of Cundinamarca (CAR) stations located throughout the middle basin. For these purposes, a multitemporal analysis of the TC and Escherichia coli variables was conducted for the 2007–2019 period, which evidenced the contamination levels in this section of the water body. In broad terms, the current state of the middle section of the Bogotá River basin is unacceptable, due to the different activities occurring within its riparian buffer zone, such as uncontrolled domestic, industrial, and/or commercial wastewater discharges. To optimize water treatability, the continuous improvement of existing treatment plants is expected, as well as the implementation of new sustainable treatment alternatives aimed at improving water quality.