Abstract In this work we model and simulate water quality parameters in a hydrological network by using a methodology based on network theory and differential equations. We build the Quindío river hydrological network based on network theory using the Gephi software, the maps from “Instituto Geográfico de Colombia Agustin Codazzi” and data reported from “Coorporacion Autónoma Regional del Quindío”. Then, we modelled three water quality parameters using differential equations at each node of the network, these are total coliforms, biochemical oxygen demand, and dissolved oxygen. As a result of the simulations, we found high levels of pollution in the area where there is a presence of human settlements and the local industry. Finally, results also showed a possible relationship between the three parameters studied, mainly due to the high concentrations in the same area of the basin.