The research assessed water quality in three rural communities in the province of Cotopaxi: La Calera, Tomailoma, and Toahilin. The objective was to determine its suitability for human consumption according to the regulations of the Unified Text of Secondary Environmental Legislation (TULSMA). Physical, chemical, and microbiological parameters were analyzed using standardized methodologies (HACH, QUICK, and Standard Methods). The results showed that the community of La Calera met most of the parameters, with the exception of fecal coliform levels exceeding the regulatory limit. Toahilin, on the other hand, had high arsenic content, representing a health risk. In Tomailoma, the parameters remained at or below the permitted limits. The Water Quality Index (WQI), according to the National Sanitation Foundation (NSF), indicated WQI values of 47.22, 38.28, and 29.86 for the communities, respectively, resulting in a classification of "Poor." Concluding that, regardless of the fact that most parameters comply with regulations, biological contamination and the presence of arsenic significantly affect water quality, it is recommended to strengthen drinking water systems with adequate treatment and community monitoring to guarantee the sustainability of the water resource.