Overview of Construction of Bagaevsky Hydroelectric Complex (May 2023)

Spillway dam

By order of the Russian President, Stroytransgaz Group of Companies continues constructing the Bagaevsky Hydroelectric Complex, the most important infrastructure project not only for the Rostov Region, but for the whole country. This project will ensure dimensions of the waterway necessary for navigation on the Lower Don, a part of the all-Russian deep-water system.

Cushion laying

At the construction site, the company continues arranging 427.5 thousand square meters pit for the spillway dam. This dam will release floodwaters from the natural reservoir formed by closing the Don River by the hydroelectric complex. As of today, the pit has reached its design depth of minus 7.2 meters. At the location of the apron and safety bucket, dewatering with needle filter units and earthworks are underway. Concrete blinding arrangement is commenced. A concrete blinding or, as they often say, a cushion is a thin layer of concrete used to cover a pit before laying the foundation. A concrete blinding not only creates a waterproofing layer, but also provides for a flat surface for the intermediate concrete base and protects the foundation from groundwater. 66 thousand cubic meters of concrete are planned to be poured on the spillway dam by the end of the year. While works are in progress in the pit, water is pumped out continuously.

Front and back sides of the left approach wall in the head race. 

- Construction of channel guide structures in the head and tail races is underway to ensure the safe passage of ships in the area of the hydroelectric complex. Excavation of the Fish Bypass and Spawning Channel is completed. Laying geotextile and reinforcing the the channel bed and slopes with crushed stone is underway. The construction of the estuary regulator of the spawning area is in progress. At this point 110 pieces of equipment and over 500 workers are involved in the project," said Denis Akhayev, Deputy General Director of Rostransmodernizatsiya.

Structurally, the walls of the guide structures (approach walls) on the front side are made of L5-UM Larssen sheet piles. On the back side there is an anchoring wall, which serves as an anchor for the front one. The face walls of the berthing facilities are a continuation of the face walls of the gateway. Foundation frame (horizontally located element of the pile foundation) is built to ensure the strength of the anchor wall. Before pouring concrete, the piles are driven and an impervious wedge is arranged.

Anchor wall coating with bitumen mastic for waterproofing

In the head race, 95% of the Larssen sheet piles of the left approach wall and 30% of the right approach wall are driven. The foundation frame inclined piles on both sides are 100% complete. Anchor slabs of the left approach wall is 10% complete and of drainage wedge is 5% complete. As for the tall race, Larssen sheet piles of the right approach wall are 45% complete and anchor slabs of the left approach wall is 30% complete.

Reinforcing of the flood bed slab of the head control gate 

Besides, the head control gate of fish passage and spawning channel, which is a hydraulic structure consisting of an inlet section, a flood bed part (an artificial bed for water stream flow) and an outlet section. In the future, the main head regulator will function to maintain the optimal water flow in the fishway/spawning channel. To date, three of the five flood bed slabs have been concreted. At the same time, installation of reinforcement is underway on two more flood bed slabs.

- In June, concreting of the foundation slab and retaining wall of the head regulator of the fish bypass and spawning canal is planned. Larsen sheet piles will continue to be driven and anchor walls will be concreted for the approach channel construction. Filling the bottom and slopes of the canal bed with crushed stone will be continued in section 11. We continue laying the concrete bedding of the spillway dam flood bed and reinforcing the flood bed sections," said Levani Khumarashvili, Director for Construction Organization of Bagaevsky hydroelectric complex of Stroytransgaz JSC.  

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


Background:
Apron is a platform in the downstream of a hydraulic structure strengthening the watercourse bottom, protecting it from erosion, balancing pulsations, and dampening the energy of water discharged into the waterway.
Safety Bucket is an end device after the apron designed to prevent washing out of the main fastening elements in the downstream of spillway dams and acting as a cushioning pool to dampen the energy of waterflow.
Race is an area where the water surface adjoins the hydraulic structure. The head race is upstream the river, 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 berthing channels with mooring assistance structures, a spillway and an earth fill dams, a meandering fishway and spawning channel and a fish passage lock, as well as 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 shore protection dams that will prevent the development of 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 3004.5 kilometre mark of the waterway of the Integrated Deep Water System (IDWS) to the Bagaevsky hydroelectric complex site at the 3089 kilometre mark of the IDWS waterway, dredging and river cut-off are envisaged.