Investor: HPP “Dabar” Ltd, Trebinje
Value of works: 67 m EUR (131 m BAM)
Broader context of the Project:
The design of using of hydro system Trebišnjica is based on the construction of several hydro technical structures (dams, accumulations, open channels, tunnels and hydro power plants) with which water from karst fields of East Herzegovina is used for irrigation, control of floods and production of electricity. The construction of 7 hydro power plants and 6 accumulation basins in the system is planned to be constructed for production of electricity.
Four hydro power plants, which use water from “Bileća” accumulation basin are constructed up to now: HPP Trebinje I, HPP Trebinje II, HPP Dubrovnik and HPP Čapljina. They were successively commissioned from 1965 (HPP Dubrovnik) to 1981 (HPP Trebinje II).
Remaining 3 hydro power plants belong to subsystem “Gornji horizonti” and as it follows: HPP Nevesinje (61 MW), HPP Dabar (160 MW) and HPP Bileća (30 MW).
The subsystem “Gornji horizonti” includes using of water on section of the Gatačko field – the Zalomka river – the Nevesinje field – the Dabar field – the Fatnica field – the Bileća accumulation. Some water from north-west part of Nevesinje field will be used in this system in the final phase.
HPP Dabar is the first hydro power plant which will be constructed in area of Gornji horizonti.
The water from Pošćenje accumulation to HPP Dabar is carried through headrace tunnel of length of 12.1 km. The headrace tunnel passes through two different geological zones. The inlet structure is located near riverbed of the Zavidolska river and it is far from Pošćenje dam about 3.5 km. The grid and gate for tunnel closure for needs of control and maintenance are designed to be constructed. Two access tunnels (Straževica in length of 830 m and Vodostan in length of 295 m) are designed to be constructed for work execution.
Contracted are works as follows:
A. INTAKE STRUCTURE, WORKING PLATEAU, CONTROL ROOM AND ACCESS ROAD
Intake structure, working plateau P=336.10m2 paved (AB11s and BNS32 d=5+10cm) on th embankment, steel railing around the plateau h=1.12m, hydrant network l= 290.00m DN100; Control room; Access road l=279.00m w=5.00m, road base d=45cm and pavement structure d=15cm; equipment-hydro-mechanical equipment for water intake structure; electrical equipment.
B. HEADRACE TUNNEL length l= 12,125.00m of longitudinal slope i=2.139‰; circular clearance of diameter D = 4.6m length 7,853.00m and horse-shoe cross-section l= 4,272.00m length of excavation 5.20m; construction technology: New Austrian Tunnel Method.
C. ADVANCE HEADINGS – Straževica tunnel and Vodostan tunnel
- Straževica tunnel: straight-line tunnel l=651.57m, excavation slope i=7.54%, horse-shoe cross section height 5.5m;
- Vodostan tunnel: staright-line tunnel l=91.00m, excavation slope i=2.139‰, circular cross-section diameter 5.2m.
D. TECHNICAL OBSERVATION
E. EXPLORATION WORKS AND DESIGN DEVELOPMENT during construction.