Physicochemical and Microbiological Characterization of Drinking Water from the Luz de América parish, Ecuador: Statistical Approach

The present research was performed in the community of Luz de America, Santo Domingo de los Tsáchilas, Ecuador, during March-April (rainy season) and October (dry season) of 2022. The study assessed the quality of the drinking water consumed in the parish by collecting 176 samples in each season, as there have been no studies on water quality in the area. Physicochemical and microbiological parameters were analyzed according to the NTE INEN 1108 standard. The percentage of compliance with the standard was determined on the basis of the water source (well, user’s tap) and the municipalities under evaluation. The highest levels of non-compliance were found for residual chlorine and total coliforms in both seasons, while turbidity showed low compliance only in the rainy season. To determine the influence of seasonality, the Wilcoxon-Pratt Signed-Rank test was applied to the variables analyzed, all of which presented a p-value < 0.05, meaning that the medians of the difference between the two seasons for each variable were different, except for total coliforms (p-value = 0.092). Kendall’s correlation matrix was used to analyze the correlation between physicochemical and microbiological variables, showing 14 significant correlations in each climatic season, of which Turbidity-Colour was the highest for both rainy and dry seasons. Finally, a website was created for the stakeholders and the public, presenting the geo-referenced results obtained in the laboratory, ensuring compliance with the main water quality parameters for the benefit of the community.