The study evaluated the quality of water intended for human consumption in the canton Quevedo, province of Los Rios, Ecuador. Physical, chemical and microbiological parameters of water in nine EPMAPAQ pumping stations were evaluated, in rainy and dry seasons. The results obtained with the reference values set out in the regulations (Ministerial Agreement No. 097 Standard INEN 1108, TULSMA, EPA and WHO) under the quality criterion for water intended for human consumption and domestic use was compared. The Water Quality Index (ICA) and the statistical correlation between parameters were determined using the test "t" of Student, with a statistical significance of p = 0.05 between the two periods. Parameters: nitrites, nitrates, turbidity, total dissolved solids, pH, total hardness, color and iron are in the range of acceptability environmental quality. Values, manganese, dissolved oxygen exceed the maximum permissible limits for the TULSMA, like fecal coliform in the rainy season. Most parameters showed significant differences ("t" 5%) between the two periods. Quevedo Canton water is slightly contaminated and requires purification treatment before consumption.
