Hainan Grids Tunnel Project Boosts Haikou Power Supply

As urban development expands across rivers, Hainan Power Grid has demonstrated how to safely and efficiently extend critical electricity infrastructure. On September 4, the 220 kV Binjiang (Guoxing) power transmission and transformation project - a key energy channel connecting Haikou's Jiangdong New Area with the city center - achieved full tunnel penetration across the river, completing the milestone 15 days ahead of schedule.

This pioneering engineering feat represents Hainan's first electricity tunnel crossing beneath a river and currently stands as the province's largest and most technically challenging power tunnel project. With total investment reaching 134 million yuan, the 1,050-meter-long tunnel will significantly enhance Haikou's power grid capacity.

Since entering the pipe jacking construction phase on June 16, the project team overcame multiple technical challenges including high water pressure in deep shafts and complex quicksand geology. Engineers employed innovative solutions featuring full-stratum informatized hard rock pipe jacking machines and real-time attitude monitoring systems to ensure tunneling precision and safety.

The final tunnel axis error was maintained within an impressive 50-millimeter tolerance , demonstrating Hainan Power Grid's advanced capabilities in constructing complex underground power infrastructure under challenging geological conditions.

"This breakthrough establishes important new benchmarks for ultra-long-distance pipe jacking construction and complex geological power projects," said Xiao Zhiqiang, General Manager of Hainan Power Grid Construction Branch under China Southern Power Grid.

Scheduled for completion by December 2023, the tunnel will substantially improve power supply capacity and reliability for Haikou's central urban area and regions west of the Nandu River. The infrastructure project represents both a technical achievement and a commitment to supporting regional economic development through reliable electricity supply.