ABSTRACT

The operating conditions of hydropower plants in Sweden are expected to change in the coming decades with potentially many hydropeaking events every day. It is therefor important to understand how inherent damping properties in rivers can be used to mitigate potential negative influences on fluvial ecosystems. The effect of the upstream dam closing time and the Manning number distribution in the reach on the transient behavior of the downstream water level and wetted area is investigated. In the study reach the shallow-water equations are solved using the open-source solver Delft3D. The simulations show that the transient change in water level is mainly dependent on the upstream dam closing time. The dynamics of the wetted area is considerably affected by the closing time of the dam. The Manning number has a negligible effect on the transient behavior for the wetted area and the water level. The results in this study can be used for future ecohydraulical applications such as identifying potential stranding zones.