River systems worldwide are currently impounded to provide societal services such as hydropower,
flood control, and recreation. Hydropower production fundamentally transforms rivers and their
ecosystems by fragmenting channels and altering river flows. The operation of hydropower plants
affect the downstream flow, thermal and sediment transport regimes, which in turn cause alterations
in river morphology, temperature patterns and surface-ground water exchanges. This results in
cascading effects on the ecological integrity of the stream, and of the adjacent aquatic and terrestrial
habitats and ecotones (i.e. backwaters and wetlands, riparian zone, etc.).
The assessment of the impacts related to hydropower production is becoming an increasingly
important topic for management including the restoration of impounded river systems. Such
assessment is also a requirement of the international legislation aiming to preserve the aquatic
ecosystems and to increase the ecological and social benefits they provide. Moreover, the definition
of release management scenarios and mitigation/restoration options in regulated rivers, requires a
comprehensive and detailed knowledge of the existing links between the physical variables and the
biota, which can only be obtained with an interdisciplinary research approach.
It is still difficult to describe, quantify and evaluate the interactions and dynamics of biotic-abiotic
process in regulated rivers, due to their complexity. Thus, this session aims to improve the
understanding of the consequences of hydropower production, with a strong focus on the links
between hydrological, hydraulic, biochemical, solid transport, and ecological processes.
For this session we solicit papers dealing with theoretical and experimental studies, involving also
scientists from fields such as environmental economy and social sciences. The main focus will be
on the following subjects:
1. Hydropeaking;
2. Environmental flows;
3. Experimental releases and flushing floods (water and sediment releases);
4. Mitigation measures.