The LTSER Zone Atelier Seine belongs to LTER-France network and is located in Seine River Basin. The ZA Seine general aim is the study of a whole region. How its inhabitants construct the aquatic environment, as well as the quality of surface- and ground-waters may be seen as the dominant scientific question. The question is posed at various scales in space (from sub-catchments to the whole basin), and in time (from historical analysis starting in the Middle-Age to prospective studies for the next century).