Overview

The Dahuashui Dam is a significant hydroelectric infrastructure project located on the Qingshuihe River in Kaiyang County, Guizhou Province, China. Structurally, it is an arch dam designed to serve the dual purposes of hydroelectric power production and flood control for the surrounding region near Pingzhai. The facility creates a substantial reservoir with a storage capacity of 276,500,000 m3 (224,162 acre⋅ft), which is critical for regulating water flow and generating electricity. The power station associated with the dam contains two generators, each with a capacity of 200 MW, contributing to the regional energy grid.

Construction of the Dahuashui Dam began in December 2003. The project initially faced scheduling challenges, with completion originally expected in May 2007. However, a lack of funding delayed the project, pushing the date of initial operation to January 20, 2008. The dam was constructed using roller-compacted concrete, a technique that offers durability and efficiency for large-scale hydroelectric structures. Since its commissioning, the dam has remained operational, continuing to provide both energy and flood mitigation benefits to Guizhou Province.

Engineering and Construction

The structure serves dual purposes: hydroelectric power production and flood control. The dam creates a reservoir with a capacity of 276,500,000 m3 (224,162 acre⋅ft), which supplies water to the associated power station containing two 200 MW generators. The entire facility is currently operational.

The project was initially expected to be completed in May 2007. However, a lack of funding delayed the project completion. Initial operation finally commenced on January 20, 2008. The dam was constructed using roller-compacted concrete (RCC), a method that offers specific engineering advantages for large-scale arch dams in the region.

Construction Timeline

Phase / Event Date Details
Construction Start December 2003 Initial groundbreaking and commencement of works on the Qingshuihe River.
Expected Completion May 2007 Original projected end date before funding delays impacted the schedule.
Initial Operation January 20, 2008 Official commissioning and start of hydroelectric power production.

The use of roller-compacted concrete was a critical engineering decision for the Dahuashui Dam. RCC involves placing thin layers of low-slump concrete and compacting them with heavy rollers, similar to earth-fill dam construction. This method allows for faster placement rates and reduced heat of hydration compared to conventional cast-in-place concrete, which is particularly beneficial for arch dams where temperature control is essential for structural integrity. The arch design itself transfers the water load laterally to the abutments of the Qingshuihe River valley, optimizing material usage and structural strength.

The funding delays that pushed the completion date from May 2007 to January 2008 highlight common challenges in large-scale infrastructure projects in Guizhou Province. Despite these delays, the dam was successfully commissioned and has since contributed to the regional energy grid with its two 200 MW generators. The reservoir also plays a significant role in flood control for the downstream areas near Pingzhai.

Technical Specifications

Dam Structure and Materials

The Dahuashui Dam is classified as an arch dam, a design choice that leverages the topography of the Qingshuihe River valley near Pingzhai in Kaiyang County, Guizhou Province, China. The structure was constructed using roller-compacted concrete (RCC), a method that allows for efficient placement and compaction of concrete layers, often reducing construction time and cost compared to traditional cast-in-place concrete methods. This construction technique contributes to the dam's stability and its dual purpose of hydroelectric power production and flood control.

Reservoir Characteristics

The dam creates a reservoir with a total volume of 276,500,000 m3 (224,162 acre⋅ft). This storage capacity is critical for regulating the flow of the Qingshuihe River, ensuring a consistent water supply for power generation while also mitigating flood risks for downstream areas in Kaiyang County. The reservoir's size supports the operational flexibility of the hydroelectric plant, allowing for adjustments in water release based on seasonal demand and inflow variations.

Power Station and Generation Capacity

This configuration provides a total installed capacity of 400 MW, although the individual unit rating is 200 MW per generator. The plant began initial operation on January 20, 2008, following a construction period that started in December 2003. The project faced delays due to funding shortages, pushing the completion date from the initially expected May 2007 to January 2008.

Parameter Value
Dam Type Arch dam
Construction Material Roller-compacted concrete
Reservoir Volume 276,500,000 m3 (224,162 acre⋅ft)
Number of Generators 2
Capacity per Generator 200 MW
Location Qingshuihe River, Pingzhai, Kaiyang County, Guizhou Province, China
Initial Operation Date January 20, 2008

What caused the delay in completion?

The construction timeline for the Dahuashui Dam experienced a notable deviation from its initial schedule, primarily driven by financial constraints. Construction on the arch dam officially began in December 2003, establishing a baseline for the project's progression. The original projection anticipated that the facility would reach completion by May 2007. This initial timeline suggested a construction period of approximately three and a half years, which is a relatively standard duration for a hydroelectric project of this scale, particularly one utilizing roller-compacted concrete technology.

However, the project did not adhere to this initial forecast. The primary factor cited for the delay was a lack of funding. Financial shortfalls are a common challenge in large-scale infrastructure development, often leading to phased construction, temporary work stoppages, or the staggered commissioning of units. In the case of the Dahuashui Dam, these funding issues extended the construction phase significantly beyond the May 2007 target date.

The delay resulted in a gap of approximately eight months between the expected completion and the actual start of operations. Instead of being fully operational in mid-2007, the dam achieved initial operation on January 20, 2008. This date marks the point at which the hydroelectric power station, containing two 200 MW generators, began supplying power from the reservoir, which has a total capacity of 276,500,000 m3 (224,162 acre⋅ft). The delay, while notable, did not ultimately prevent the dam from fulfilling its dual purpose of hydroelectric power production and flood control for the region near Pingzhai in Kaiyang County, Guizhou Province, China.

The reliance on roller-compacted concrete for the dam's construction may have influenced the funding dynamics, as this method often allows for cost efficiencies and faster pouring rates compared to traditional concrete methods. Despite the financial hurdles that pushed the completion date into early 2008, the project was successfully realized, demonstrating the resilience of the construction planning in the face of economic variables. The initial operation date of January 20, 2008, stands as the definitive milestone for the dam's entry into service, superseding the earlier May 2007 projection.

Significance

The Dahuashui Dam serves as a critical node in the energy infrastructure of Guizhou Province, China, providing both hydroelectric power generation and essential flood control capabilities for the region. Located on the Qingshuihe River near Pingzhai in Kaiyang County, the facility is designed as an arch dam constructed with roller-compacted concrete, a technology choice that supports structural integrity and efficient water management in the local topography.

Hydroelectric Power Contribution

The plant became operational on January 20, 2008, marking a key milestone in the regional energy mix after construction began in December 2003. The project faced delays due to funding constraints, with initial completion expected in May 2007, but the eventual commissioning in 2008 ensured a steady supply of hydroelectric power to the provincial grid. This capacity supports the growing energy demands of Guizhou, leveraging the water resources of the Qingshuihe River to provide a renewable energy source that complements other power generation methods in the area.

Flood Control and Regional Impact

Beyond energy production, the Dahuashui Dam plays a vital role in flood control on the Qingshuihe River. The reservoir's ability to store 276,500,000 m3 of water allows for effective management of seasonal water flows, reducing the frequency and severity of flooding in Pingzhai and surrounding areas in Kaiyang County. This dual-purpose design enhances the resilience of local infrastructure and supports agricultural stability by regulating water availability throughout the year. The dam's operational status remains active, continuing to provide these critical services to the region and demonstrating the integrated approach to water resource management in China's hydroelectric development strategies.

Geographic Context

The Dahuashui Dam is situated in the southwestern Chinese province of Guizhou, specifically within Kaiyang County. The facility is located near the town of Pingzhai, placing it in a region characterized by the complex topography typical of the Guizhou highlands. The dam is constructed directly on the Qingshuihe River, which serves as the primary water source for the hydroelectric power generation and flood control functions of the project. This geographic positioning allows the dam to harness the flow of the Qingshuihe River to create a significant reservoir, essential for the operation of the power station.

Guizhou Province provides a distinct geographic setting for the Dahuashui Dam. The province is known for its mountainous terrain and extensive karst landscapes, which influence the hydrological characteristics of rivers such as the Qingshuihe. The location near Pingzhai in Kaiyang County places the dam in an area where water management is critical for both energy production and local flood mitigation. The reservoir created by the dam has a capacity of 276,500,000 m3 (224,162 acre⋅ft), a volume that reflects the specific catchment area and topographic constraints of the Qingshuihe River valley in this part of Guizhou.

The choice of location on the Qingshuihe River was integral to the dam's design as an arch dam. Arch dams are particularly suited to narrow, steep-sided valleys, which are common in the mountainous regions of Guizhou Province. The geographic constraints of the site near Pingzhai influenced the construction methods, leading to the use of roller-compacted concrete for the dam structure. This construction technique is often employed in regions where the topography and material availability favor efficient, layered concrete placement. The geographic context of Kaiyang County thus directly impacted the engineering decisions made during the project's development, from the initial construction start in December 2003 to its completion in January 2008.

Operational History

The Dahuashui Dam has maintained a continuous operational status since its initial operation commenced on January 20, 2008. This hydroelectric facility, located on the Qingshuihe River near Pingzhai in Kaiyang County, Guizhou Province, China, serves a dual purpose of hydroelectric power production and flood control for the surrounding region. The plant remains active as a key infrastructure asset in the local energy grid, leveraging the water resources of the Qingshuihe River to generate electricity.

The power station is equipped with two generators, each with a capacity of 200 MW, providing a combined installed capacity of 200 MW as specified in the project parameters. These units draw water from the dam's reservoir, which holds a volume of 276,500,000 m3 (224,162 acre⋅ft). The consistent operation of these generators ensures a steady output of hydroelectric power, contributing to the energy needs of Guizhou Province. The roller-compacted concrete construction of the dam, completed after funding delays that pushed the timeline from an expected May 2007 to January 2008, has proven durable for ongoing operations.

Since 2008, the dam has continued to fulfill its designed functions without major reported disruptions to its core hydroelectric output. The reservoir's capacity allows for effective water management, supporting both power generation and flood mitigation strategies in the Kaiyang County area. The operational history reflects the project's successful transition from construction challenges to stable long-term utility, maintaining its role in the regional energy infrastructure. The facility's ongoing operation underscores the importance of hydroelectric resources in China's energy mix, particularly in the mountainous terrain of Guizhou Province.

See also