Twenty-five years of research in hydro-ecology at the EDF research and development division

Hydro-ecology (or aquatic ecology) is the study of aquatic systems in their interacting aspects: physical, chemical and biological. The creation in 1974 of the Environment Department at EDF Research and Development Division marked the start in France of quantitative hydro-ecology applied to power generation installations. The studies developed around several main themes, determined both the expansion of the nuclear programme and by changes in French environmental regulations, in particular the 1976 law on impact studies, the 1984 fishing and hydro-biology law and the 1992 water law. In this framework, he effect of artificial warming of rivers, eutrophication of continental and marine waters, transfers of mineral micro-pollutants and radionuclides in rivers, and problems specific to hydropower installations such as guaranteed in stream flow or fish pass design, have been studies. This work, conducted in collaboration with many other laboratories, has led to the development of original quantitative approaches, notably in the field of numerical modelling. The paper selects several of the tools developed whose scope of application is wider than the environment and management of thermal or hydropower plants. Two major applications grouping the experience acquired in hydro-ecology are presented: the AGIRE software and the global environment study of the Singrauli area in India. (author)