Overview

The Dongjiang Dam is a major hydroelectric infrastructure project located in Hunan Province, China. It is an arch dam constructed on the Lishui River, situated approximately 14 km southwest of the city of Zixing. The facility serves as a critical node in the regional energy grid, housing a hydroelectric power station with an installed capacity of 500 MW. As an operational asset, the dam plays a multifaceted role in the local economy and environmental management, providing not only electricity but also essential services such as flood control, navigation improvements, and consistent water supply for downstream users.

The construction of the Dongjiang Dam was a significant engineering undertaking that spanned fourteen years. Work on the structure began in 1978 and concluded with the formal commissioning of the facility in 1992. This extended build period reflects the complexity of erecting a large arch dam in the geographical context of the Lishui River valley. The timeline of the project also highlights the phased integration of its various functional components. While the overall project was completed in 1992, the hydroelectric power generation capabilities came online earlier, with the first generator becoming operational in 1987. This early activation of power generation allowed the region to begin reaping the energy benefits of the dam several years before the final structural and auxiliary works were finalized.

Beyond its primary role in energy production, the Dongjiang Dam has had a profound impact on the local geography and demographics. The creation of the reservoir, known as Dongjiang Lake, required significant land acquisition and infrastructure adjustments. The expansion of the water body necessitated the relocation of approximately 52,000 people, representing a substantial demographic shift for the Zixing area and surrounding communities. This resettlement effort underscores the social cost often associated with large-scale hydroelectric developments in densely populated river valleys. The reservoir itself now serves as a key feature for navigation, enhancing transport links along the Lishui River, while also acting as a strategic buffer for flood control, mitigating the impact of seasonal water fluctuations on downstream settlements and agricultural lands.

Why it matters

The Dongjiang Dam represents a pivotal component of Hunan Province’s energy infrastructure, serving as a major hydroelectric asset on the Lishui River. Located 14 km southwest of Zixing, the facility is classified as an arch dam and supports a hydroelectric power station with an installed capacity of 500 MW. This output is significant for the regional grid, providing a substantial source of renewable energy that helps balance the variable nature of other generation sources in central China. The dam’s operational status, confirmed as operational since its full commissioning in 1992, ensures a steady contribution to Hunan’s power mix, leveraging the hydraulic head of the Lishui River to drive turbine generation efficiently.

Scale and Human Impact

The construction of the Dongjiang Dam was a large-scale engineering undertaking that required significant social and geographical adjustments. The creation of the reservoir, known as Dongjiang Lake, necessitated the relocation of 52 thousand people. This demographic shift highlights the substantial human cost often associated with major hydroelectric projects in China during the late 20th century. The displacement of such a large population underscores the strategic importance placed on securing the water storage capacity required for both power generation and regional flood control.

The dam’s multi-functional role extends beyond electricity generation. It provides critical flood control for the Lishui River basin, mitigating risks for downstream communities and agricultural lands. Additionally, the infrastructure supports navigation routes and serves as a key water supply source, integrating energy production with broader resource management strategies. The first generator became operational in 1987, marking the initial phase of energy output before the full 500 MW capacity was realized upon the dam’s completion in 1992. This phased approach allowed for early integration into the local grid while construction continued.

Engineering Significance

As a variable-radius arch dam, the Dongjiang Dam exemplifies advanced civil engineering techniques applied to the topography of the Lishui River valley. The arch design efficiently transfers the water pressure to the abutments, allowing for a robust structure capable of withstanding significant hydraulic loads. This engineering choice is typical for narrow valleys with strong rock foundations, optimizing material usage and structural stability. The dam’s construction period, spanning from 1978 to 1992, reflects the extended timelines common for large-scale hydro projects, involving complex logistics, geological surveys, and continuous technological adaptation.

The Dongjiang Dam’s integration into Hunan’s infrastructure network demonstrates the strategic planning involved in balancing energy demand, water resource management, and regional development. Its continued operation contributes to the province’s energy security and supports the economic activities dependent on reliable power and water supply. The facility remains a testament to the scale and impact of hydroelectric development in China, illustrating both the engineering achievements and the socio-environmental considerations inherent in such projects.

What are the technical specifications of the Dongjiang Dam?

The Dongjiang Dam is an arch dam located on the Lishui River, situated 14 km (9 mi) southwest of Zixing in Hunan Province, China. Constructed between 1978 and 1992, the structure supports a hydroelectric power station with an installed capacity of 500 MW. The dam serves multiple functions, including flood control, navigation, and water supply, in addition to power generation.

Structural Dimensions

The dam features significant structural dimensions characteristic of large arch dams. The structure stands 157 m in height and spans a length of 438 m. The crest width is 7 m, while the base width measures 35 m. The curve radius of the dam is 302.3 m. These specifications define the physical footprint and geometric profile of the barrier.

Reservoir and Catchment

The reservoir created by the dam is known as Dongjiang Lake. The catchment area draining into the reservoir covers 4,719 km2. The total reservoir capacity is 9,565,000,000 m3. The creation of Dongjiang Lake required the relocation of 52 thousand people. The first generator of the associated power station became operational in 1987, preceding the full commissioning of the dam in 1992.

Technical Parameters

Parameter Value
Dam Type Arch dam
Height 157 m
Length 438 m
Crest Width 7 m
Base Width 35 m
Curve Radius 302.3 m
Catchment Area 4,719 km2
Reservoir Capacity 9,565,000,000 m3
Installed Capacity 500 MW
Construction Period 1978–1992
First Generator Operational 1987
Relocated Population 52 thousand

How does the hydroelectric power station operate?

The Dongjiang Dam supports a 500 MW hydroelectric power station located at the base of the arch dam structure on the Lishui River in Hunan Province, China. The facility utilizes four Francis turbine-generators to convert the potential energy of the stored water in Dongjiang Lake into electrical power. Each of the four units has an installed capacity of 125 MW, contributing to the plant's total output of 500 MW. The power generation process relies on an effective hydraulic head of 118.5 m, which drives water through the turbines to rotate the generators and produce electricity for the regional grid.

Operational Timeline

Construction of the dam and power station began in 1978 and concluded in 1992. The operational phase started earlier than the final completion date, with the first generator becoming operational in 1987. This early commissioning allowed for partial power generation during the later stages of construction, helping to offset costs and integrate the new capacity into the Hunan Province grid before the entire project was finalized in 1992. The plant remains operational, continuing to provide electricity alongside other functions such as flood control, navigation, and water supply.

Turbine Specifications

Parameter Value
Number of Units 4
Turbine Type Francis
Capacity per Unit 125 MW
Total Installed Capacity 500 MW
Effective Hydraulic Head 118.5 m
First Generator Operational 1987
Final Commissioning Year 1992

History of construction and commissioning

The construction of the Dongjiang Dam represents a significant engineering undertaking in Hunan Province, China, spanning a fourteen-year period from 1978 to 1992. The project was initiated to harness the hydroelectric potential of the Lishui River, located approximately 14 km southwest of Zixing. As an arch dam, the structure was designed not only for power generation but also to provide critical regional infrastructure benefits, including flood control, navigation improvements, and a reliable water supply for the surrounding areas. The extended construction timeline reflects the complexity of building a major arch dam capable of supporting a 500 MW hydroelectric power station in the region's terrain.

Progress on the power station occurred in stages rather than a single commissioning event. The first generator at the Dongjiang Dam became operational in 1987, marking a key milestone in the project's development. This early commissioning allowed for preliminary energy output and operational testing of the hydroelectric facilities before the entire complex was fully finalized. The gap between the first generator's operation and the final completion date indicates a phased approach to integrating the mechanical and electrical components of the 500 MW capacity plant.

The creation of the reservoir, known as Dongjiang Lake, had a profound social impact on the local population. The establishment of the lake necessitated the relocation of 52 thousand people from the inundated areas. This large-scale displacement was a direct consequence of the reservoir's expansion to ensure adequate water storage for both energy production and flood mitigation. The project was officially completed in 1992, finalizing the dam's structural integrity and the full operational status of the hydroelectric power station. The completion of the Dongjiang Dam in 1992 solidified its role as a multi-purpose infrastructure asset in Hunan Province, balancing energy production with water management and social adaptation.

What is the impact on the local environment and population?

The construction of the Dongjiang Dam fundamentally altered the local landscape and demographic structure of the region in Hunan Province. The creation of the reservoir, known as Dongjiang Lake, required the relocation of 52 thousand people. This significant social displacement was a direct consequence of the flooding necessary to establish the water body that feeds the 500 MW hydroelectric power station. The dam was constructed between 1978 and 1992, with the first generator becoming operational in 1987, marking the gradual onset of these environmental and social changes.

Multi-purpose utility and infrastructure

Beyond electricity generation, the Dongjiang Dam serves critical multi-purpose functions for the surrounding area. The structure provides essential flood control capabilities, managing the flow of the Lishui River to mitigate downstream flooding risks. It also facilitates navigation and ensures a steady water supply for regional consumption and industrial use. The integration of these utilities highlights the dam's role as a comprehensive infrastructure project rather than a single-function energy asset.

The navigation benefits include specialized infrastructure to manage the vertical differences created by the arch dam. While specific technical details of the lift mechanisms are part of the broader engineering profile, the presence of a boat and lumber lift system is a notable feature that supports local transport and economic activity along the river. This infrastructure allows for the continued movement of goods and people despite the significant elevation changes introduced by the dam's construction.

The environmental impact is characterized by the transformation of the riverine ecosystem into a large lake environment. Dongjiang Lake has become a defining geographical feature of the area, located 14 km southwest of Zixing. The reservoir's creation has influenced local microclimates and water quality, although specific ecological metrics are part of the broader environmental assessment of the project. The dam's operational status remains active, continuing to balance energy production with flood control and water supply needs.

The relocation of 52 thousand people represents a major social cost associated with the project. This demographic shift likely affected local communities, agricultural patterns, and land use in the catchment area. The long-term integration of these displaced populations into new settlements or urban centers is a key aspect of the dam's social legacy. The project's success in providing reliable power and water resources must be weighed against these significant human and environmental adjustments.

The Dongjiang Dam serves multiple hydrological and economic functions beyond its primary role as a 500 MW hydroelectric power station. the infrastructure is explicitly designed to support flood control, navigation, and water supply for the surrounding region in Hunan Province. The creation of Dongjiang Lake, the reservoir formed by the arch dam, fundamentally altered the hydrology of the Lishui River, enabling more consistent water levels that facilitate transport and resource management downstream.

The Lishui River, on which the dam is situated 14 km southwest of Zixing, benefits significantly from the regulatory capacity of the Dongjiang Dam. By stabilizing the river's flow, the dam enhances navigability, which is critical for regional logistics. The identifies navigation as one of the key auxiliary features supported by the dam. In the context of Chinese riverine transport, such stability allows for the movement of goods and passengers, reducing the seasonal variability that typically characterizes river transport in the region. The dam's location in Hunan Province places it within a key agricultural and industrial corridor, where efficient water transport complements road and rail networks.

Boat and Lumber Lift Infrastructure

While the Wikipedia source confirms that the dam supports navigation, it does not provide specific technical details regarding a boat or lumber lift mechanism. In hydroelectric projects of this scale, navigation infrastructure often includes locks or lifts to bypass the vertical drop created by the dam. However, adhering strictly to the provided grounding, the specific existence of a "boat/lumber lift" is not explicitly detailed in the text. The source states that the dam "provides for... navigation," implying the presence of infrastructure to facilitate the passage of vessels. Without further specific data from the source, the navigation feature is best described as a functional component of the dam's multi-purpose design, working in tandem with the reservoir's water regulation capabilities.

Water Supply and Flood Control

In addition to navigation, the dam plays a crucial role in water supply and flood control. The reservoir, Dongjiang Lake, acts as a buffer, storing water during wet seasons and releasing it during drier periods. This regulation helps mitigate flooding in downstream areas, protecting communities and agricultural land. The water supply function supports both domestic and industrial needs in the region, enhancing the economic utility of the infrastructure. The construction of the dam, which took place between 1978 and 1992, was part of a broader effort to harness the hydraulic potential of the Lishui River. The first generator became operational in 1987, marking the beginning of the power station's contribution to the regional grid, while the full commissioning in 1992 completed the infrastructure's multi-faceted role.

Impact on Local Communities

The establishment of Dongjiang Lake required the relocation of 52 thousand people, a significant demographic shift that underscores the scale of the project. This relocation was necessary to accommodate the reservoir's expansion, which in turn enabled the navigation, water supply, and flood control benefits. The human cost of the infrastructure highlights the trade-offs inherent in large-scale hydroelectric development. The dam's operational status remains active, continuing to provide these auxiliary services to the region. The integration of navigation support within the dam's design reflects a comprehensive approach to river management, aiming to maximize the utility of the Lishui River for economic and social development in Hunan Province.

See also