Water is the best example of circularity in nature. Everybody remembers clearly the charts showing the water cycle on biology textbooks in high schools. Snow, rain, tributaries, lakes, seas, evaporation, plant nutrition, source of life for animals, basic resource for man’s social and economic development. In a continuous cycle of changes of state and ontological mutations. A perfect cycle with a complex geography, crossing a global scale (water is a supranational resource circulating incessantly) and a regional and non-territorial scale (water basins do not stop at administrative or national borders). Nowadays, water as an essential resource for mankind, is faced with a geographical issue.     Political geography often clashes with physical geography, without dov...