Expert Opinion for Acquiring-Prolonging Water Permit for “Višegrad” HPP for Period 2021-2026
MH Power Utility of RS, ZP “Hidroelektrane na Drini”(HPPs on Drina) Višegrad
In period from December 2021 till February 2022, Zavod has developed “Expert opinion for acquiring – extension of water permit for Višegrad HPP’s operation in period 2021-2026” including additional hydrological analyses (development of the new hydrological time series) for Visegrad HPP’s partition profile, for the needs of Associated Company Hidroelektrane na Drini Ltd., Višegrad.
Basic standing point for development of the Expert opinion which is necessary for issuing water license for constructed objects and Višegrad HPP operation is Decision on issuing water permit no. 01/3-BA.1-1255-5/16 of 05.07.2016, and checking if the conditions from this water permit are met.
Based on the working meetings held with Višegrad HPP representatives, and insight in documentation submitted by the Visegrad HPP’s expert team and detailed terrain prospection, it was concluded if and in what extent the conditions from the previous water permit have been met.
Part of this contract was also development of additional hydrological analyses (development of the new representative hydrological time series) for HPP Visegrad partition profile, after that updating of existing documentation was performed, namely, of „Study on assessment of environmental flow“ in 2013, taking into consideration of possibly changed hydrological conditions on the river basin compared to period of almost 10 years ago.
Analyses were performed on several hydrological time series of observed mean annual flows on the Drina river on Visegrad HPP’s dam profile. Results were compared and representative sample was selected and mean annual flows of various probabilities of occurrence were identified. Statistical analyses of both daily and monthly low water was implemented, for acquiring entrance parameters for identification of environmental flow. EF was determined based on the regulations in force as well as on recommended methods.
After reviewing the specification of realistic and necessary obligations, Expert team concluded that conditions from the previous water permit have been met and issued proposal for possible improvements in the field of preserving the quality of watercourses, and performing monitoring of watercourses quality (of the Drina river downstream of Višegrad HPP and Višegrad reservoir), water regime regulations and watercourses regulations, control of water management systems, and recommendations for strengthening data bases and bases on status of key objects of the system and information capacities of Drina HPP as well as recommendation in the field of hydro-morphology and erosion.