Bagaevsky Hydroelectric Complex Construction Overview

Spillway Dam Reinforcement

In the Rostov Region, Stroytransgaz Group is proceeding with construction of the Bagaevsky Hydroelectric Complex, one of the largest transport infrastructure facilities in the South of Russia. This project, ensuring, among other things, the required navigable waterway dimensions, is considered to be a reliable solution to the navigation issues in the Lower Don River that will allow for enhancement of the waterway capacity after its execution.

The activities being performed at the construction site include the works in the spillway dam pit, fish bypass and spawning channel, as well as on Arpachinsky Island which is to feature a shipping lock, approach channels with mooring and guiding structures and a central control room.

Head Control Gate

All the concrete blinding arrangement activities have been completed in the spillway dam pit 427.5 thous. m² in area, to ensure waterproofing and to protect the foundation against ground water. Over 3 thous. cubic metres of cement mixture have already been laid.

The spillway dam comprising 12 sections with overall length of 307 metres is now being reinforced. The dam will feature a concrete spillway with a wide threshold, a flat lifting and lowering gate, and is designed to ensure the required flood discharge and control the navigational water flow. The Larssen sheet pile driving operations to build the cut-off wall in the spillway dam foundation are still in progress.

‘The dam construction and erection works, including the foundation plate reinforcement, concrete placement, driving of cut-off piles into the tail race, are underway at the site. The lock construction operations include pit excavation and driving of sheet piles into the channel guiding structures. The concrete works being underway along the fish bypass and spawning channel include construction of the control gate piers, slope forming and reinforcement of the channel bed with stone’, – says Denis Akhaev, Deputy Director General of Rostransmodernizatsiya Federal State Unitary Enterprise.

Construction of channel guiding structures of similar design in the head and tail races is underway to ensure safe passage of ships in the area of the hydroelectric complex.

The mooring structure along the left side of the navigation pass is adjacent to the bank and consists of an anchored bulwark and a mooring structure including a thin vertical wall and anchor facilities. The distance between the axes of the front sheet pile wall and anchor slabs is 20 m. The front sheet pile wall is 100 % complete, 862 pcs. of Larssen sheet piles have been driven. The front sheet pile wall will be anchored on inverted T-shaped cast reinforced concrete anchor plates. Concreting of the anchor wall is 90 % complete. The crushed stone wedge consisting of crushed stones and two layers of Dornit geotextile is made to prevent soil leakage through the holes in the sheet pile wall at the anchor rod fastening points. Construction of the drainage wedge at minus 2 m level is complete.

The waling is being constructed, including fabrication and laying of about 40 linear meters, to ensure additional reinforcement and stability of the sheet piling.

In order to fix the anchor rods, 40 holes 115 mm in diameter, 700 holes 66 mm in diameter have been made in the front and anchor walls, and 1,200 holes 34 mm in diameter have been made in the waling for further bolting.

The entirety of the mooring structure along the right side of the navigation pass is located offshore. The front and end walls are made from Larssen sheet piles, with 700 pcs. having already been driven. Construction of the first-level drainage wedge is in progress.

The mooring structure end sections have curvilinear shape. These sections are anchored on the pile foundation frame (the top part of the pile foundation that distributes the load from the load-bearing components). Driving of inclined piles of both foundation frames is complete; reinforcement activities along the left side are underway.

The Larssen sheet pile driving is 89 % completed, the inclined piles are fully driven, the construction of the first-level drainage wedge is underway along the right side of the lower approach channel with mooring and guiding structures.

The mooring structure along the left side of the navigation pass is made by Larssen sheet pile driving; the construction of anchor slabs is 70 % complete. Driving of inclined piles of the foundation frame is 60 % complete.

Works are under way along the following sections of the fish bypass and spawning channel: head control gate (a hydraulic structure consisting of an inlet section, a flood bed part and an outlet section), channel line and spawning grounds.

‘All five flood bed slabs and three bases of retaining walls have been completed at the head control gate of the fish bypass and spawning channel. Reinforcement of vertical elements of retaining walls is in progress. Next week we will proceed to concreting of the fourth base. The channel line development is in progress, the excavation is underway. The works are underway at the inlet control gate of the first spawning ground and at the control gate of the fifth spawning ground’, says Levany Khumarashvily, the Director for Bagaevsky Hydroelectric Complex Construction Management at Stroytransgaz.

Rostransmodernizatsiya Federal State Unitary Enterprise is the state customer of the project.

For reference:

Race is the area where the water surface comes into contact with hydraulic structure. The head race is upstream, while the tail race is downstream.

Project background:

The Bagayevsky Hydroelectric Complex is the most important infrastructure project not only for the Rostov region, but also for the whole country. The hydroelectric complex under construction will be composed of a shipping lock with a central control room, upper and lower approach channels with mooring-guiding structures, a spillway and earth fill dams, a meandering fish bypass and spawning channel and a fish passage lock, industrial, service, engineering and auxiliary facilities, and housing for operating personnel. To ensure the navigation safety, channel-regulating dams are being constructed, as well as bank protection dams that will prevent bank erosion processes (washout and collapse), protect from the impact of ship waves and reduce the negative impact of waters on the population living in these areas. In order to ensure guaranteed waterway dimensions (depth — 4 m, width — 80 m, bending radius — 500 m) in the section from the Kochetovsky Hydroelectric Complex site at the 3,004.5 kilometre mark of the waterway of the Integrated Deep Water System (IDWS) to the Bagaevsky Hydroelectric Complex site at the 3,089 kilometre mark of the IDWS waterway, dredging and river cut-off are envisaged.