Geomembrane Anti-Seepage System in Jurong Pumped Storage Power Station: Innovative Application, Construction Practice & Award Analysis by Shandong Jiantong

Introduction

With the continuous advancement of China’s “Dual Carbon” strategy, pumped storage power stations have become a vital component of the modern power system, and their construction standards are becoming increasingly stringent. In Jurong, Jiangsu Province, a world-class pumped storage power station is redefining industry understanding of reservoir anti-seepage systems.

Shandong Jiantong Plastics Technology Co., Ltd., as both the geomembrane supplier and construction contractor for this project, completed the supply and installation of 186,000 square meters of HDPE geomembrane, 450,000 square meters of composite drainage net, and 15,000 square meters of new-type geomembrane. The company also undertook the anchoring construction within the HDPE and TPO geomembrane systems. With its outstanding performance, Jiantong was awarded the First Prize of the 2025 Power Construction Science and Technology Progress Award and the First Prize of the Hydropower Science and Technology Progress Award.

Taking this project as an example, this article analyzes the technical challenges and solutions of geomembrane composite anti-seepage systems under conditions of high water head and large deformation.

Project Background

The State Grid Xinyuan Jiangsu Jurong Pumped Storage Power Station is a key national project under China’s 13th Five-Year Plan, with a total investment of RMB 9.606 billion and an installed capacity of 1.35 million kilowatts. It is recognized as the world’s highest pumped storage dam, the highest asphalt concrete face rockfill dam, and the largest reservoir basin filling project.

Located in a region with complex geological conditions, the project is characterized by frequent and significant water level fluctuations and a massive reservoir basin fill area. These conditions make traditional single-layer anti-seepage solutions insufficient for long-term stable operation. The anti-seepage system must not only withstand high hydraulic pressure differences but also adapt to deformation caused by temperature variations and uneven foundation settlement.

Core Solution

The main structures of the Jurong project include the upper reservoir, lower reservoir, water conveyance system, underground powerhouse, and switchyard. In response to the complex working conditions, Shandong Jiantong Plastics Technology Co., Ltd. developed a new type of geomembrane after extensive technical discussions and validation, successfully overcoming the challenge of reliable welding between HDPE geomembrane and dissimilar materials.

For the upper reservoir, a combined anti-seepage system of asphalt concrete panels and geomembrane was adopted. In excavation areas, 1.5 mm thick HDPE geomembrane was used, covering approximately 194,000 square meters, with a three-dimensional composite drainage net installed beneath it. In fill areas, 1.5 mm and 2.0 mm thick TPO geomembranes were applied, covering about 279,800 square meters, also with composite drainage nets underneath.

The HDPE geomembrane served as the primary anti-seepage layer, offering extremely low permeability, high strength, excellent chemical stability, and long-term aging resistance. The newly developed geomembrane, known as XHDPE, enhanced flexibility and elongation compared to traditional HDPE, significantly improving its adaptability to deformation and low-temperature conditions while extending service life.

In this system, the new geomembrane eliminated the need for anchoring between the geomembrane and drainage gallery, instead forming a welded connection with both HDPE and TPO membranes. Meanwhile, the composite drainage net effectively prevented water and gas accumulation beneath the membrane, reducing uplift pressure risks and providing additional protection.

TPO geomembrane, as a newly introduced material in hydropower anti-seepage applications, was applied for the first time in this project under research led by PowerChina Northwest Engineering Corporation. However, due to variations in formulations among manufacturers and limited long-term performance verification, careful selection is required.

Construction Technology

In the Jurong project, Jiantong was responsible for the anchoring construction of HDPE and TPO geomembranes. Geomembrane installation is a critical process that directly affects the overall anti-seepage performance of the project. Jiantong’s experienced construction team demonstrated strong technical capabilities and adaptability in overcoming multiple on-site challenges.

During construction, difficulties such as encountering reinforcing steel when drilling anchor holes, uneven concrete surfaces affecting installation quality, and excessive rainfall leading to water accumulation in galleries were successfully addressed. Additional issues, including cracking between HK elastic sealant and geomembrane edges and gaps between angle steel and cover plates, were also resolved through advanced welding techniques and strict quality control.

With professional expertise, modern equipment, and extensive field experience, Jiantong ensured the smooth progress and timely completion of the project.

Awards and Technical Strength

As a key participant, Shandong Jiantong Plastics Technology Co., Ltd. played an essential role in both the technological development and engineering application of the Jurong project. The company received the First Prize of the 2025 Power Construction Science and Technology Progress Award and the First Prize of the Hydropower Science and Technology Progress Award.

Through independent research and development, Jiantong successfully introduced new HDPE geomembrane technologies, significantly improving puncture resistance and multi-directional deformation adaptability. These innovations effectively addressed the tearing risks associated with ultra-high fill reservoir conditions.

The application of this technology in the upper reservoir anti-seepage system ensured safe water storage and long-term stable operation by controlling leakage risks caused by uneven settlement. Furthermore, this achievement has filled a technical gap in China’s anti-seepage solutions for ultra-high fill reservoirs and has been incorporated into industry standards, providing a replicable solution for similar projects worldwide.

Conclusion

The successful implementation of the Jurong pumped storage power station demonstrates the reliability and effectiveness of geomembrane anti-seepage systems under complex geological and operational conditions.

For projects in hydropower, solid waste management, and transportation infrastructure, this integrated solution combining anti-seepage, drainage, protection, and anchoring offers significant reference value and practical applicability.