Abstract : After forty years of environmental public policies, drinking water and municipal waste management changed. For instance, the paradigm of environmental sectors management evolved, the legislation strengthened and the emergence of new environmental issues changed the territorial organizations... Step by step, territorial actors created new forms of organization, in regard to the special issues of their territories. What kind of forms these evolutions can take ? What are the territorial trajectories ? Can we observe some straightness ? Who governs these dynamics and what is the role of territorial public institutions ? The thesis shows the existence of different forms of territorial organizations at the "départemental" level of the French institutions, dealing with public services involved to the drinking water and municipal waste management. With four monographs, the thesis shows the power of advocacy coalitions and urban cities in the trajectories of evolution. These appear also oriented by different regulation's hybridization phenomena. With all these results, the author proposes at last to contribute to the analysis's lexicon of this domain of research.