Operational forecasting model of the prevention and accumulation river basin Modrac

The Modrac Reservoir is a reservoir located mostly in the municipality of Lukavac, although it also touches the outskirts of the cities of Tuzla and Živinica. The Modrac Dam was built in 1964 on the Spreča River, which simultaneously formed the reservoir of the same name, with the main purpose of securing the necessary quantities of water for production processes of industrial capacities in the area of ​​the municipalities of Lukavac and Tuzla.

Multi-purpose reservoir Modrac is a key water management facility of special importance for the life of the population, industry and tourism of the Tuzla Canton and as such for the entire Tuzla Canton but also BiH represents an inestimable value that requires special treatment, permanent investment and quality maintenance and management. By applying modern technologies used for operation and management of multi-purpose reservoirs and associated hydroelectric power plants, it is possible today to manage such water management systems in the most efficient way, to the benefit of all participating factors. Along with water supply and tourism, one of the key purposes and functions of the Modrac reservoir is flood protection in downstream areas.

This paper will present an operational prognostic local model of the Spreča River, which includes the Spreča River basin from its source to the Karanovac hydrological station. The developed local hydrological prognostic model of the river Spreča was created with a total of 6 sub-basins, the total size of the modeled basin is about 1,900 km².

In the subject hydrodynamic model, a total of more than 180 km of watercourses were modeled as 13 river sections, 2 Q2D branches and 8 connecting channels within the Q2D sections. The geometry of the modeled sections is defined with approximately 230 cross-sections.

The subject paper will present the calibration of the hydrological and hydrodynamic model of the Spreča River for the associated catchment up to HS Karanovac, for water levels and flows, and was carried out for the period 2020-2023. Based on the prognostic model, a prognostic system for predicting floods in real time was created, which will also be presented in this paper.

The local operating system of the Spreča River, as well as other systems managed by the Agency for the Sava River Water Area, are compatible with the prognostic system developed in Croatia, which enables a simple exchange of input data.   

Keywords: Modrac reservoir, Spreča river, hydrological-hydrodynamic model, prognostic model, operational system, flood forecasting