Overview

The Yantan Dam is a gravity dam located on the Hongshui River in Dahua County, Guangxi, China. As a key component of the region's hydroelectric infrastructure, the structure serves primarily for hydroelectric power production. The facility is operated by the Guangxi Electric Power Bureau and has been operational since its commissioning in 1992. The dam's design leverages the natural head of the Hongshui River to drive its associated power station, contributing to the energy grid of southern China.

The hydroelectric power station integrated with the Yantan Dam has an installed capacity of 1210 MW. This generating capacity is derived from four Francis turbine-generators, each with a rated output of 302.5 MW. Francis turbines are a common choice for medium-head hydroelectric projects, offering high efficiency and reliability for continuous power generation. The configuration of four units allows for flexible operation, enabling the plant to adjust output based on river flow variations and grid demand.

Located in Dahua County within the Guangxi Zhuang Autonomous Region, the Yantan Dam is part of the broader development of the Hongshui River basin, which is one of China's most significant hydroelectric corridors. The gravity dam structure relies on its own weight to resist the horizontal force of the water, providing stability and durability for long-term operation. The primary purpose of the dam remains hydroelectric power production, although such structures often provide secondary benefits such as flood control and water storage, though specific details on these auxiliary functions are not explicitly detailed in the primary operational data.

The commissioning of the Yantan Dam in 1992 marked a significant milestone in the energy infrastructure of Guangxi. The facility continues to operate under the management of the Guangxi Electric Power Bureau, contributing to the regional energy mix. The use of Francis turbines and the gravity dam design reflect engineering choices optimized for the specific hydraulic conditions of the Hongshui River at this location. The plant's operational status remains active, with the four turbine-generators providing a consistent power output of 1210 MW to the grid.

History

The development of the Yantan Dam was formally recognized when the project was placed on the state key project list in 1984. This designation marked the beginning of the formal planning phase for the gravity dam on the Hongshui River. Construction activities commenced in March 1985, initiating the physical transformation of the site near Dahua County in Guangxi. The engineering team executed the river diversion in November 1987, a critical milestone that allowed for the main structure to be built in a relatively dry riverbed. The reservoir was subsequently impounded in March 1992, establishing the water head necessary for power generation. The project involved significant human displacement, with 43176 people relocated to accommodate the new reservoir and infrastructure.

Commissioning of Generators

The power station, operated by the Guangxi Electric Power Bureau, features a total capacity of 1210 MW. This output is generated by 4 x 302.5 MW Francis turbine-generators. The commissioning process for these units spanned nearly three years, starting with the first generator coming online on September 16, 1992. The final unit was commissioned in June 1995, completing the installation of the four Francis turbines. The plant has remained operational since its initial commissioning, serving as a key hydroelectric asset in the region. The construction timeline from the start in 1985 to the final commissioning in 1995 reflects the scale of the gravity dam project.

Engineering Design and Specifications

Dam Structure

The Yantan Dam is constructed as a gravity dam, a structural design that relies on its own weight to resist the horizontal force of the water. The structure stands 110 m high and extends 525 m in length along the crest. This configuration is situated on the Hongshui River, providing the necessary hydraulic head for the associated power station. The dam's gravity design ensures stability through the interplay of hydrostatic pressure and the concrete mass, a common engineering approach for large-scale hydroelectric projects in the region.

Reservoir Characteristics

The reservoir formed by the Yantan Dam plays a critical role in regulating the flow of the Hongshui River for both power generation and downstream water management. The storage capacities are defined by specific volume metrics that dictate operational flexibility. The normal reservoir capacity is 2612000000 m3, representing the standard operating level for consistent power output. The maximum reservoir capacity reaches 3432000000 m3, allowing for additional storage during periods of high inflow or flood control needs. The active storage volume, which is the portion of the reservoir most frequently cycled for power generation, is 1572000000 m3. These volumes enable the plant to maintain a steady water supply to the Francis turbines, optimizing energy production across varying seasonal flows.

Parameter Value
Dam Height 110 m
Dam Length 525 m
Normal Reservoir Capacity 2612000000 m3
Maximum Reservoir Capacity 3432000000 m3
Active Storage Volume 1572000000 m3

Spillway System

The spillway system is essential for managing excess water and preventing overtopping of the dam structure during peak flow events. The Yantan Dam features a spillway equipped with seven radial steel gates. These gates allow for precise control over the discharge rate, ensuring that water levels remain within safe operational limits. The total discharge capacity of the spillway is 33400 m3/s, providing significant flood relief capability for the Hongshui River basin. The use of radial gates is a standard engineering choice for large dams, offering a balance of structural efficiency and hydraulic performance. This discharge capacity ensures that the dam can handle substantial inflows, protecting both the infrastructure and downstream communities from potential flooding.

Power Station Infrastructure

The Yantan Dam's power generation infrastructure is located at the right toe of the gravity dam structure. The powerhouse building is a substantial concrete structure measuring 200 meters in length, 60 meters in width, and 72 meters in height. This facility houses the primary electromechanical equipment responsible for converting the hydraulic energy of the Hongshui River into electrical output.

Water is directed into the power station through four distinct intakes. From these intakes, the flow is channeled through penstocks that feed the turbine-generators. After passing through the runners, the water is discharged into the tailrace channels, completing the hydrological cycle for power production. The design utilizes Francis turbine-generators, which are well-suited for the head and flow characteristics of the Hongshui River at this location.

Installed Capacity and Equipment

The station contains four identical generating units. Each unit is equipped with a Francis turbine coupled to a generator with a rated output of 302.5 MW. The total installed capacity of the power station is 1,210 MW. This capacity is achieved through the summation of the four 302.5 MW units. The firm capacity of the plant, representing the minimum output expected under normal operating conditions, is 242 MW.

Specification Value
Powerhouse Dimensions 200 m (L) x 60 m (W) x 72 m (H)
Number of Units 4
Turbine Type Francis
Unit Capacity 302.5 MW
Total Installed Capacity 1,210 MW
Firm Capacity 242 MW
Intakes 4

The operational status of the Yantan Dam power station is operational. The facility has been in service since its commissioning in 1992. The Guangxi Electric Power Bureau serves as the operator of the hydroelectric powerplant. The infrastructure supports the broader energy grid in Guangxi, China, utilizing the water resource of the Hongshui River for continuous power generation.

What is the function of the Yantan Ship Lift?

The Yantan Dam infrastructure on the Hongshui River serves a dual purpose, combining significant hydroelectric generation with critical navigational improvements for inland water transport in Guangxi. While the primary function of the facility is power production, the integration of the Yantan Ship Lift addresses the challenge of maintaining river connectivity for commercial barges despite the elevation changes created by the gravity dam structure. This multipurpose design ensures that the Hongshui River remains a viable artery for regional logistics, allowing vessels to bypass the reservoir’s headwater levels efficiently.

Vertical Lift Mechanism and Capacity

The Yantan Ship Lift is engineered as a vertical lift type system, a technology specifically chosen to manage the substantial height difference between the upstream and downstream water levels of the dam. Unlike inclined plane lifts or canal locks, a vertical lift utilizes a hoisting mechanism to raise and lower a boat carrier or caisson directly up and down the dam’s face or adjacent tower structure. This method is often more water-efficient and faster for vessels of specific size ranges, reducing transit time for commercial traffic.

According to the technical specifications of the infrastructure, the ship lift is designed to accommodate a maximum vessel weight of 250 tons. This capacity allows standard inland barges used in the Guangxi region to traverse the dam without requiring extensive transshipment of cargo. The 250-ton rating reflects the typical load-bearing requirements for the Hongshui River’s commercial fleet, ensuring that the lift can handle fully loaded freighters common to the local waterway economy. The design prioritizes reliability and throughput, essential for maintaining the flow of goods such as agricultural products, minerals, and manufactured items along the river corridor.

Integration with Hydroelectric Operations

The presence of the ship lift complements the dam’s primary role as a 1,210 MW hydroelectric power station. The power station consists of four Francis turbine-generators, each with a capacity of 302.5 MW, which regulate the river’s flow to generate electricity. The navigation infrastructure must operate in harmony with these hydrological controls. The vertical lift system is integrated into the overall dam design to minimize interference with water intake for the turbines and to maintain structural stability of the gravity dam. This coordination ensures that power generation schedules and vessel transit times are optimized, reducing downtime for both energy output and riverine transport. The multipurpose nature of the Yantan Dam thus exemplifies modern hydraulic engineering, where energy production and navigational efficiency are balanced to maximize regional economic benefit.

Why it matters

The Yantan Dam stands as a pivotal infrastructure asset in the development of Guangxi’s hydroelectric capacity, specifically along the Hongshui River near Dahua County. As a gravity dam, it serves primarily for hydroelectric power production, housing an associated power station with a total installed capacity of 1210 MW. The plant’s technical configuration includes four Francis turbine-generators, each rated at 302.5 MW, contributing significantly to the regional energy mix and grid stability in southern China.

Strategic Importance and State Recognition

The project was designated as a state key project, underscoring its strategic importance to the national and regional energy infrastructure of China. Its development reflects the broader efforts to harness the hydraulic potential of the Hongshui River, a major waterway in the Guangxi Zhuang Autonomous Region. The scale of the Yantan Dam project highlights the engineering ambitions of the early 1990s, aiming to balance power generation efficiency with the geographical constraints of the river basin. As an operational hydroelectric powerplant, it continues to play a crucial role in supplying renewable energy to the region, supporting industrial growth and residential demand in Guangxi.

Engineering and Construction

The design and construction of the Yantan Dam involved specialized local expertise. The project was designed by the Guangxi Electricpower Investigation and Design Institute, which tailored the gravity dam structure to the specific hydrological and geological conditions of the Hongshui River. Construction was executed by the Guangxi Yantan Hydropower Project Construction Corporation, ensuring that the engineering standards met the requirements for a state key project. The successful integration of four 302.5 MW Francis turbine-generators demonstrates the technical precision achieved during the build phase, resulting in a reliable 1210 MW power output that has sustained operations since 1992.

Socio-Economic Impact and Relocation

The development of the Yantan Dam had a profound socio-economic impact on the local population, particularly in Dahua County. The scale of the project necessitated the relocation of 43176 people, reflecting the significant human cost and community restructuring involved in large-scale hydroelectric development. This mass relocation underscores the extensive planning required to manage displacement, infrastructure development, and economic integration for the affected residents. The project’s legacy includes not only the physical infrastructure of the dam and power station but also the transformed demographic and economic landscape of the surrounding areas in Guangxi.

How does Yantan Dam compare to other hydro projects in Guangxi?

The Yantan Dam serves as a critical node within the hydroelectric infrastructure of Guangxi, situated on the Hongshui River near Dahua County. As a gravity dam, its structural design relies on mass and weight to resist the horizontal force of the water, a common and robust engineering choice for the region’s topography. Its primary function is hydroelectric power production, contributing to the energy mix of the province through a dedicated power station.

The power station associated with the Yantan Dam has a total installed capacity of 1,210 MW. This capacity is generated by four Francis turbine-generators, each rated at 302.5 MW. The Francis turbine is a widely used type of water turbine, known for its efficiency across a wide range of flow rates and heads, making it suitable for the conditions found on the Hongshui River. The specific configuration of four units allows for modular operation and maintenance, ensuring consistent power output to the regional grid.

While the Yantan Dam is a significant contributor to Guangxi’s hydroelectric output, specific comparative data with other dams in the region is not detailed in the available sources. The Hongshui River basin is known for hosting multiple hydroelectric projects, each contributing to the overall energy security of the area. The Yantan Dam’s 1,210 MW capacity places it among the notable facilities in the basin, though exact rankings relative to other projects require additional data not present in the current grounding. The gravity dam design and the use of Francis turbines reflect standard engineering practices for large-scale hydroelectric projects in China during the period of its construction.

The operational status of the Yantan Dam remains active, indicating its continued relevance in the energy infrastructure of Guangxi. The dam’s location near Dahua County also suggests a role in local water management, although the primary purpose cited is power production. The Guangxi Electric Power Bureau’s operation of the facility ensures that it is integrated into the broader provincial energy strategy, contributing to the stability and reliability of the power supply in the region.

See also