In the district of Belén, Iquitos, the Lupunilla and Masana streams are important sources of water, however, they present significant levels of contamination due to anthropogenic activities. The research, carried out in 2023, evaluated the physicochemical and microbiological properties of the water in both streams to compare them with the environmental quality standards (ECA) of Peru. The physicochemical properties of the waters analyzed revealed the following: The pH varies between 6.22 and 7.04; the electrical conductivity is between 65.8 and 97.2 μS/cm; Total dissolved solids reach values of up to 48.8 mg/L. A total hardness of up to 542.5 mg/L was found in the growing season. Regarding alkalinity, it varies between 0.6 and 1.25 mg/L of CaCO3, while chlorides have values between 4.87 and 10.64 mg/L. Turbidity and color also showed significant variations, with a maximum of 687.5 neph...