Currently there are many environmental problems caused about difference reasons, one of them is pollution by pesticides and heavy metals. Being one of the most worrying factors of the national and international present time and given the consequences for the environment and the living beings as the plants, animals and the human beings, it is necessary to achieve with regular processes of monitoring and different studies, in order to be able to take the preventive and corrective measures according to the case. The authors present us with the results of their research, allowing us to observe the way and proportion the factors analyzed in the Repelón irrigation district are distributed; as well as, the analysis of the impact that allows us to identify the way in which the waters and sediments of “The Guájaro” reservoir are being affected.