This work presents questions related to the viability and the requirements for the implementation of a National Policy of Water Resources in Brazil, and identifies the means to bring about active participation by the population in the management of water resources. While social inequalities may be an impediment to the implementation of full participation, it is argued that facing the problems related to participatory management of water resources is to be dealt with in the field of rationality, and mediation has been chosen as the central theoretical construct to guide the process of environmental education and empowerment through action research. Examples of formal and non-formal environmental education activities are brought from actions developed closely with the Commission for Water Basin Committee of High Maranhao River, Central Brazil. (Contains 2 figures.)