The thesis focuses on problems that do not only affect the river Tržiška Bistrica, but are also common to other parts of Slovenia. The biggest problem lies in the poor condition of the dams, which has various negative consequences. The most problematic among them is the hindered passage of river organisms over the dams as the fishways are, just like the dams themselves, also in poor condition or even non-existent. This causes habitat fragmentation, harming organisms in and along the rivers. The second big problem is related to dry riverbeds, a major culprit for killing off several species of organisms living in or near the rivers. To counter the excessive levels of water abstraction, the government issued the Decree on criteria for determination and on the mode of monitoring and reporting of ecologically acceptable flow, which prevents owners of smaller hydroelectric plants from abstracting too much water.
The main goals of the decree are to ease the passage of river organisms as well as to enable ecologically sustainable river discharge levels while increasing the number of peak hours of hydroelectric plants. Based on the chosen goals and conditions, the thesis proposes a solution for the reconstruction of the dam providing water for the small hydroelectric plant Zvirče, which is one of several dams on the Tržiška Bistrica. The proposed solutions are part of a preliminary design including all the necessary calculations and technical drawings. The proposal is based on the theoretical framework as well as on examples pertaining to other working dams and older projects that were left unfinished for various reasons.