Abstract

The article describes the physicochemical and microbiological characteristics of both the existing drinking water supply system in the Las Brisas district located in the canton of Zarcero, and the surface water of the Jilguero River that crosses said community. The negative impact of human activities on water resources during the years 2019-2021 is assessed to determine its vulnerability based on the analysis of 45 freshwater samples. The most important results are: 1- There are levels of ammonium and phosphate in the aqueduct water that, during the rainy season, run off and leach into the springs, coming from the expansive agricultural development. 2- The pH and free chlorine are two parameters that need to be improved in the Las Brisas aqueduct, to reduce risks and ensure the potability of the water throughout the distribution network. 3- The contamination of the Jilguero River is classified between moderate and severe according to national regulations, a situation motivated by the intense agricultural activity in the area, as well as the disrespect for the river's protection zones.

Key words: water quality; hydric health; environmental chemistry; drinking water; surface water