Relationship Between Microbiological and Physicochemical Parameters in Water Bodies in Urabá, Colombia

The presence of pathogens, toxic substances, and excess nutrients in rivers is due to the combination of industrial, agricultural, and livestock farming activities, as well as the absence of wastewater treatment plants and sewerage networks. River degradation is the result of these factors. The results from four monitoring campaigns of water quality, carried out between November 2023 and August 2024, in the rivers of northern Urabá, Colombia, are presented in this paper, and the relationships between physicochemical and microbiological parameters are assessed. Water samples from 16 sites, upstream, downstream, and within urban centers, as well as at the mouths of the Hobo, Zapata, and Damaquiel rivers, and two water bodies flowing into the coastal lagoon of Bahía El Uno are presented. Five water quality factors were analyzed at using Spearman’s correlation analysis (p = 0.005). The results revealed negative correlations between dissolved oxygen (DO) and coliforms (−0.49), and positive correlations between temperature and total dissolved solids (TDS) (0.365). The elevated content coliforms exceeding permissible Colombian standards to total coliforms (˂200 MPN/mL) and thermotolerance (1000 MPN/mL) reached 8,400,000 and 24,000,000 MPN/mL, respectively, indicating that urban discharges increase microbial loads and induce degradation of conditions in the study area.