1. Awards & Honors

2021 POWERCHINA Science and Technology Progress Award — First Prize

Award-winning achievement: Key Technologies for High-Quality and Efficient Roller-Compacted Concrete Dam Construction at the Kafue Gorge Lower Hydropower Project, a Model Belt and Road Project.

The achievement developed a systematic set of technical solutions covering roller-compacted concrete dam structural optimization, material and mix design, interlayer construction quality control, construction efficiency, and temperature control and crack prevention.

2021 Science and Technology Award of the Chinese Society for Rock Mechanics & Engineering — Second Prize

Award-winning achievement: Key Technologies for Rock Mass Utilization in Confined Spaces at the Kafue Gorge Lower Hydropower Project, a Model Belt and Road Project.

The achievement was jointly completed by Sinohydro Bureau 11 Co., Ltd., POWERCHINA Northwest Engineering Corporation Limited, Tsinghua University and other participating organizations.

During construction, the project also generated multiple patents, construction methods and software copyrights, while developing a series of technological innovations in roller-compacted concrete dam construction, rock mass utilization in confined spaces, intelligent monitoring and complex underground hydraulic structures.

2. Project Background / Project Background

The Kafue Gorge Lower Hydropower Station (KGL) is located on the Kafue River in Zambia’s Southern Province, approximately 90 km southeast of Lusaka, the national capital.

The hydropower station has a total installed capacity of 750 MW, consisting of five 150 MW Francis turbine-generator units. The main dam is a roller-compacted concrete gravity dam with a height of 130.5 m, a crest length of 374.5 m, and a total concrete volume of approximately 1.3 million m³.

From the perspective of Zambia’s national energy system, the Kafue Gorge Lower Hydropower Station is one of the country’s most significant large-scale infrastructure projects in more than four decades and an important part of Zambia’s long-term hydropower development strategy. ZESCO positions the project as a key component of the cascade hydropower development system along the Kafue River, enabling more efficient utilization of the river’s hydropower resources in coordination with upstream facilities.

The project contract was signed in November 2015, after which the project moved into the construction phase. On June 6, 2018, the first placement of roller-compacted concrete for the dam was completed. Reservoir impoundment began in November 2020. The first generating unit entered operation on July 1, 2021, and on March 24, 2023, the fifth unit was commissioned, marking the full operation of all five units.

From the perspective of international cooperation, the Kafue Gorge Lower Hydropower Station is one of the flagship projects of high-quality Belt and Road cooperation between China and Zambia. A joint venture formed by Sinohydro Bureau 11 and POWERCHINA Northwest Engineering Corporation undertook major construction works, with Sinohydro Bureau 5 also participating in project implementation.

3. Engineering Challenges

3.1 130.5 m Roller-Compacted Concrete Gravity Dam with High Temperature-Control Requirements

The Kafue Gorge Lower Hydropower Station features a 130.5 m-high roller-compacted concrete gravity dam with a crest length of 374.5 m and approximately 1.3 million m³ of concrete.

For such large-volume concrete construction, cement hydration generates substantial internal heat. Excessive differences between internal temperature rise, surface heat dissipation and ambient temperature can create thermal stresses.

Therefore, hydration heat control, placement temperature, interlayer bonding, curing and construction sequencing were all critical factors in dam quality control.

The project carried out dedicated technical research on the RCC material system, interlayer construction quality and rapid dam construction, resulting in the development of key technologies for high-quality and efficient RCC dam construction.

3.2 Continuous Large-Volume RCC Construction Requiring Both Efficiency and Quality

RCC dam construction requires a highly continuous system covering mixing, transportation, spreading, compaction and interlayer treatment.

The project needed to improve concrete placement and spreading efficiency while strictly controlling compaction quality, interlayer bonding and construction organization on the dam surface.

Systematic research was conducted on full-section RCC placement, high-volume fly ash utilization, cement grout treatment between layers and refined construction of grout-enriched vibrated RCC zones, supporting efficient large-scale dam construction.

3.3 Complex Underground Hydraulic Structures and Rock Mass Construction in Confined Spaces

In addition to the dam, the project includes a water conveyance system, surge system, underground caverns and powerhouse-related hydraulic structures.

Underground construction had to address confined working spaces, complex rock mass stability and coordination among multiple hydraulic structures.

The project developed a green construction approach characterized by “strong protection, light excavation and minimal disturbance.”

Through precise investigation, dynamic design and refined construction, the project improved the safety and efficiency of complex underground rock engineering works.

3.4 Complex “Seven Tunnels and One Shaft” Large-Diameter Surge Structure

The project features an innovative large-diameter special-shaped surge structure characterized by “seven tunnels and one shaft.”

The integrated arrangement of multiple underground tunnels and a large surge shaft placed high requirements on excavation sequencing, rock stability, structural design, construction coordination and safety management.

POWERCHINA has described this structure as the “world’s first surge shaft of its kind,” and it has become one of the project’s representative technical innovations.

3.5 Complex Installation and Integrated Commissioning of Five Large Hydropower Units

The power station is equipped with five 150 MW Francis turbine-generator units, providing a total installed capacity of 750 MW.

From reservoir impoundment to the water conveyance system, unit installation, electrical equipment, control and protection systems, substations and transmission facilities, the project required coordinated commissioning across multiple systems.

After the first unit entered operation, the remaining units were progressively installed and commissioned, with all five units fully operational by March 2023.

4. Houde Products Applied

For large hydropower projects similar to the Kafue Gorge Lower Hydropower Station, Houde product solutions are mainly suited to four core requirements: water reduction, retarding and workability control for mass hydraulic concrete; hydration heat and long-term durability control; crack resistance, seepage control and waterstopping for hydraulic structures; and high-strength grouting for turbine-generator units and equipment foundations.

For roller-compacted concrete gravity dams and other mass hydraulic concrete structures requiring stable construction performance, temperature control and long-term durability, Houde Polycarboxylate High-Performance Water Reducer (Retarding Type) and Houde High-Performance Mineral Admixture can be applied to improve concrete workability, increase density and optimize long-term durability.

For crack resistance and dimensional stability of hydraulic concrete, Houde Expansive Agent for Hydraulic Concrete can be applied.

For construction joints, movement joints and seepage-control applications in hydraulic structures, Houde Polymer Waterstop can be used.

For turbine-generator units, equipment foundations and structural connection points requiring high-strength grouting, Houde High-Strength Non-Shrink Grout can be applied.

5. Technical Solution

The Kafue Gorge Lower Hydropower Station is centered on a large roller-compacted concrete gravity dam and integrates water-retaining structures, water conveyance systems, surge facilities, a powerhouse, electromechanical equipment and power transmission facilities into a complete hydropower engineering system.

5.1 Roller-Compacted Concrete Gravity Dam Technology

The project adopts a roller-compacted concrete gravity dam with a height of 130.5 m and a crest length of 374.5 m.

RCC technology improves the construction efficiency of mass concrete through mechanical spreading and compaction, while also placing strict requirements on concrete material performance, VC value control, interlayer bonding, construction organization and construction continuity.

The project optimized full-section quasi-three-graded RCC, high-volume fly ash utilization and interlayer construction technologies, enabling more efficient dam construction and generating a series of engineering technology achievements.

5.2 Dam Temperature Control, Crack Prevention and Long-Term Durability

For a 100 m-class mass concrete dam, controlling hydration heat, internal temperature rise and temperature gradients is a key part of construction quality management.

The project applied systematic control measures involving concrete mix design, placement temperature, material systems, interlayer bonding and curing to reduce the risk of thermal cracking in mass concrete.

These technologies were ultimately incorporated into the project’s key technologies for high-quality and efficient RCC dam construction, which received the First Prize of the POWERCHINA Science and Technology Progress Award.

5.3 Green Construction Technology for Complex Rock Masses

For confined construction spaces and complex underground structures, the project adopted the “strong protection, light excavation and minimal disturbance” technical approach.

By reducing disturbance to the original rock mass, strengthening construction-stage protection and dynamically adjusting construction solutions, the project improved the stability and safety of complex underground hydraulic works.

The project’s Key Technologies for Rock Mass Utilization in Confined Spaces received the Second Prize of the 2021 Science and Technology Award of the Chinese Society for Rock Mechanics & Engineering.

5.4 “Seven Tunnels and One Shaft” Surge System

The project developed an innovative large-diameter special-shaped surge structure featuring “seven tunnels and one shaft.”

Through coordinated operation of the surge shaft and multiple underground tunnels, the system regulates hydraulic pressure fluctuations in the water conveyance and turbine system.

It is one of the most representative underground hydraulic engineering innovations of the Kafue Gorge Lower Hydropower Station.

5.5 Intelligent Construction and Safety Monitoring

The project adopted a laser-controlled automatic mechanical leveling system and the DAMS-IV intelligent distributed engineering safety monitoring system.

Mechanical automation, digital technologies and engineering safety monitoring were integrated to provide continuous control over construction quality and structural conditions, supporting both dam construction and long-term safe operation.

5.6 Coordinated Operation of Five Francis Turbine-Generator Units

The station is equipped with five 150 MW Francis turbine-generator units, with a total installed capacity of 750 MW.

By utilizing the hydropower resources of the Kafue River cascade system, the project increases Zambia’s domestic power supply while also strengthening grid peaking, frequency regulation and regional power exchange capabilities.

6. Project Outcomes

The Kafue Gorge Lower Hydropower Station achieved full operation of all five generating units on March 24, 2023, establishing a total hydropower capacity of 750 MW.

6.1 Addition of 750 MW of Large-Scale Clean Energy Capacity

The Kafue Gorge Lower Hydropower Station is equipped with five 150 MW generating units, bringing the total installed capacity to 750 MW.

Following full commissioning, the project significantly increased Zambia’s national installed generation and power supply capability.

According to ZESCO, the project increased Zambia’s installed electricity generation capacity by approximately 38%.

6.2 Cumulative Power Generation Exceeding 10.5 Billion kWh

As the five generating units progressively entered operation, the Kafue Gorge Lower Hydropower Station continuously supplied electricity to Zambia’s national grid.

By the end of December 2024, cumulative electricity generation had exceeded 10.5 billion kWh, making the station an important hydropower source for Zambia and the wider Southern African power system.

6.3 Improved National Power Supply Capacity

The commissioning of the Kafue Gorge Lower Hydropower Station increased available hydropower capacity in Zambia’s national grid.

The project supports mining, manufacturing, agriculture, commercial activity and household electricity consumption while also contributing to grid peaking and frequency regulation.

6.4 Creation of Approximately 15,000 Local Jobs

During the construction period, the project created approximately 15,000 local employment opportunities.

Project construction also stimulated local industries including building materials, trade, transportation and mining, extending the economic and employment benefits beyond the hydropower station itself.

6.5 Development of Local Skilled Professionals

A Sinohydro training school was established at the project site to provide professional training in surveying, welding, mechanical maintenance and other engineering skills.

Public project information indicates that the training program developed more than 300 local skilled workers, supporting both project construction and the long-term development of Zambia’s infrastructure workforce.

6.6 Strengthening Regional Power Connectivity

The Kafue Gorge Lower Hydropower Station serves Zambia’s domestic power system while also supporting the country’s participation in regional electricity exchanges through the Southern African power network.

When all units were commissioned, the Zambian side stated that, after meeting domestic demand, the additional generation capacity could further strengthen electricity cooperation with neighboring countries including Malawi, Zimbabwe, South Africa and Namibia.

7. Key Figures

8. Value to China & Zambia

8.1 Value to Zambia

For Zambia, the Kafue Gorge Lower Hydropower Station is first and foremost a major clean-energy infrastructure project that strengthens the country’s power supply capability.

The project added 750 MW of hydropower capacity and increased Zambia’s installed electricity generation capacity by approximately 38%.

For mining, manufacturing, agriculture, commercial activity and residential electricity consumption, a more stable power supply provides essential support for economic activity and industrial development.

Second, the Kafue Gorge Lower Hydropower Station improves the utilization efficiency of the Kafue River cascade hydropower system.

Located downstream of the existing upstream hydropower facilities, the project further utilizes the hydropower potential of the same river basin and increases the total generation capability of the Kafue River hydropower system.

Third, the project continues to deliver substantial electricity output.

By the end of December 2024, cumulative electricity generation had exceeded 10.5 billion kWh, providing a sustained supply of clean electricity to Zambia and the wider Southern African power system.

Fourth, the project contributed to local employment and skills development.

Approximately 15,000 construction-period jobs and the training of more than 300 skilled workers extended the project’s value beyond electricity generation to employment, professional development and local industrial growth.

8.2 Value to China

For China, the Kafue Gorge Lower Hydropower Station is a representative overseas project demonstrating Chinese capabilities in the design, construction, equipment integration and organization of large-scale hydropower infrastructure.

The project integrates a 100 m-class roller-compacted concrete gravity dam, large-scale hydraulic concrete works, complex underground caverns, the “seven tunnels and one shaft” surge structure, electromechanical installation and intelligent engineering monitoring.

Together, these elements demonstrate the comprehensive implementation capabilities of Chinese enterprises in major overseas hydropower projects.

Second, the project generated hydropower engineering technologies with strong replication and application value.

The Key Technologies for High-Quality and Efficient RCC Dam Construction and Key Technologies for Rock Mass Utilization in Confined Spaces received the First Prize of the POWERCHINA Science and Technology Progress Award and the Second Prize of the Science and Technology Award of the Chinese Society for Rock Mechanics & Engineering respectively.

Third, from a Houde brand communication perspective, the Kafue Gorge Lower Hydropower Station is a representative engineering scenario for overseas large-scale hydropower material solutions.

The project features a 750 MW hydropower installation, a 130.5 m RCC gravity dam, approximately 1.3 million m³ of concrete, mass concrete temperature control and crack prevention, hydraulic structure seepage control and waterstopping, and equipment foundation grouting.

For similar large hydropower projects, Houde can provide material solutions including Polycarboxylate High-Performance Water Reducer (Retarding Type), High-Performance Mineral Admixture, Expansive Agent for Hydraulic Concrete, Polymer Waterstop and High-Strength Non-Shrink Grout, supporting hydraulic concrete workability, long-term durability, crack resistance, seepage control and electromechanical equipment installation.

Zambia Kafue Gorge Lower Hydropower Station Key Figures

Project Name: Zambia Kafue Gorge Lower Hydropower Station / Kafue Gorge Lower Hydropower Station

Country: Zambia

River: Kafue River

Distance from Lusaka: Approx. 90 km

Project Type: Large-scale hydropower station

Total Installed Capacity: 750 MW

Unit Configuration: 5 × 150 MW Francis turbine-generator units

Dam Type: Roller-Compacted Concrete Gravity Dam

Dam Height: 130.5 m

Dam Crest Length: 374.5 m

Total Concrete Volume: Approx. 1.3 million m³

Maximum Impoundment Height: 129 m

Maximum Reservoir Capacity: Approx. 84 million m³

Contract Signing: November 2015

First RCC Placement: June 6, 2018

Reservoir Impoundment: November 2020

First Unit Commissioned: July 1, 2021

Full Commissioning: March 24, 2023

Cumulative Power Generation: Over 10.5 billion kWh as of the end of December 2024

Increase in National Installed Generation Capacity: Approx. 38%

Local Employment During Construction: Approx. 15,000 jobs

Main Contractor: POWERCHINA / SINOHYDRO

Representative Honors: 2021 POWERCHINA Science and Technology Progress Award — First Prize; 2021 Science and Technology Award of the Chinese Society for Rock Mechanics & Engineering — Second Prize

Recommended Material Solutions: Polycarboxylate High-Performance Water Reducer (Retarding Type), High-Performance Mineral Admixture, Expansive Agent for Hydraulic Concrete, Polymer Waterstop, High-Strength Non-Shrink Grout

FAQ

Q1: What is the Kafue Gorge Lower Hydropower Station?

The Kafue Gorge Lower Hydropower Station (KGL) is a large hydropower project located on the Kafue River in Zambia, approximately 90 km southeast of Lusaka.

The project has a total installed capacity of 750 MW and consists of five 150 MW Francis turbine-generator units.

Q2: What is the installed capacity of the Kafue Gorge Lower Hydropower Station?

The Kafue Gorge Lower Hydropower Station has a total installed capacity of 750 MW, comprising five 150 MW Francis turbine-generator units.

All five units were fully operational by March 24, 2023.

Q3: How high is the dam of the Kafue Gorge Lower Hydropower Station?

The project features a roller-compacted concrete gravity dam with a height of 130.5 m and a crest length of 374.5 m.

The total concrete volume of the project is approximately 1.3 million m³.

Q4: When did the Kafue Gorge Lower Hydropower Station enter operation?

The first generating unit entered operation on July 1, 2021.

On March 24, 2023, the fifth unit was commissioned, marking the full operation of all five generating units.

Q5: How much electricity has the Kafue Gorge Lower Hydropower Station generated?

By the end of December 2024, cumulative electricity generation from the Kafue Gorge Lower Hydropower Station had exceeded 10.5 billion kWh.

The power station continues to provide clean electricity to Zambia and the wider Southern African power system.

Q6: What were the main engineering challenges of the Kafue Gorge Lower Hydropower Station?

The project faced several major engineering challenges, including temperature control for a 100 m-class RCC gravity dam, large-scale continuous concrete placement, complex underground rock construction, the “seven tunnels and one shaft” surge structure, and the installation and commissioning of five large turbine-generator units.

Q7: What technical awards has the Kafue Gorge Lower Hydropower Station received?

The project achievement Key Technologies for High-Quality and Efficient Roller-Compacted Concrete Dam Construction at the Kafue Gorge Lower Hydropower Project received the First Prize of the 2021 POWERCHINA Science and Technology Progress Award.

The project achievement Key Technologies for Rock Mass Utilization in Confined Spaces at the Kafue Gorge Lower Hydropower Project received the Second Prize of the 2021 Science and Technology Award of the Chinese Society for Rock Mechanics & Engineering.

Q8: What outcomes has the Kafue Gorge Lower Hydropower Station achieved?

The project added 750 MW of hydropower capacity and significantly increased Zambia’s national electricity generation capability.

By the end of December 2024, cumulative electricity generation had exceeded 10.5 billion kWh.

During construction, the project also created approximately 15,000 local jobs and trained more than 300 local skilled workers.

Q9: Which Houde products are suitable for similar large hydropower projects?

For large hydropower projects similar to the Kafue Gorge Lower Hydropower Station, Houde can recommend Polycarboxylate High-Performance Water Reducer (Retarding Type), High-Performance Mineral Admixture, Expansive Agent for Hydraulic Concrete, Polymer Waterstop and High-Strength Non-Shrink Grout according to different structural and construction requirements.

Polycarboxylate high-performance water reducers and high-performance mineral admixtures are suitable for workability and long-term durability control of mass hydraulic concrete.

Expansive agents for hydraulic concrete are suitable for crack resistance and dimensional stability.

Polymer waterstops are suitable for seepage control and waterstopping at structural joints.

High-strength non-shrink grout is suitable for turbine-generator units, equipment foundations and other high-strength grouting applications.

Q10: Why is the Kafue Gorge Lower Hydropower Station a representative case for hydropower material solutions?

The Kafue Gorge Lower Hydropower Station combines a 750 MW hydropower installation, a 130.5 m roller-compacted concrete gravity dam, approximately 1.3 million m³ of concrete, mass concrete temperature control and crack prevention, hydraulic structure seepage control, complex underground structures and equipment foundation grouting.

These engineering scenarios cover multiple application areas including concrete admixtures, mineral admixtures, crack-control materials, waterstopping materials and special grouting materials, making the project highly representative of material solution requirements for large hydropower engineering.