Abstract
Historically, populations have generally sought to settle around water sources such as rivers, lakes, and wetlands, among others. These populations and population growth also bring as a consequence a greater requirement of water for their activities; however, at the same time, wastewater also originates, which is discharged mainly into these same bodies of water, which over time generates a negative impact on flora and fauna. The objective of the research was to make a dynamic model with the Stella software to carry out a prospective study of the water quality around the physicochemical and microbiological parameters of the Patarcocha lagoon, before the dumping of residual water by the surrounding population. As a result of the model, in a period of 20 years from 2010 to 2030, the population of human settlements around the Patarcocha lagoon will grow (to 35 000), generating an increase in residual water discharge from 8.97 L/s to 9.9 L/s; This brings as a consequence that the parameters of the water of the lagoon in the same period vary such as: nitrate will increase up to 3.2 mg/L, the phosphorus will fluctuate between 78 mg/L to 81 mg/L, the dissolved oxygen will increase, the BOD5 will increase (to 125 mg/L), the pH will increase (up to 7.5) and Temperature ( to 10.5 °C), this would cause alterations in the water quality of the lagoon. This research allows decision makers to assume management measures in order to protect water resources that are very important for life.