Haidong Tunnel Breakthrough Marks Key Milestone for Central‑Yunnan Water Diversion Scheme

According to Xinhua News Agency, Haidong Tunnel, the fifth‑longest tunnel of the Central‑Yunnan Water Diversion Project constructed by China Railway No.5 Engineering Group under China Railway, has achieved full breakthrough after eight years of arduous underground construction work.

Stretching for 25.313 kilometres, Haidong Tunnel sits within the geologically active zone to the east of the Cangshan‑Erhai region. It ranks among the most challenging tunnel sections across the whole water‑transfer scheme, with exceptionally high construction risks. 

The tunnel’s alignment cuts through eleven fractured fault zones together with one active fault belt. Class‑V surrounding rock accounts for as much as 60 per‑cent of its total length, bringing a formidable combination of unfavourable underground geological conditions for the building teams. 

Site crews established a complete risk‑management framework integrating advanced geological detection, graded hazard control and dynamic adjustment of working procedures. 

Fresh construction techniques and revised execution plans were adopted throughout the works, delivering a series of important technical advances for long‑distance mountain tunnelling.

The Central‑Yunnan Water Diversion Project forms one of 172 major national water conservancy schemes confirmed by the State Council. It represents the largest‑scale and highest‑investment water‑resource redistribution initiative across south‑west China, and it remains the biggest in‑construction water diversion undertaking nationwide. The main water conveyance channel runs 664 kilometres in total. 

Once fully completed, the infrastructure will serve thirty‑four water‑receiving zones spread across six prefectures and cities, bringing benefits to roughly 11.12 million local residents. This strategic water project carries vital significance for livelihood improvement and ecological protection across Yunnan province.

The recent breakthrough at Haidong Tunnel opens up the principal water‑transport corridor for the Dali section of the wider scheme. It addresses existing weak points within the regional water‑supply network and offers robust engineering safeguards for urban‑rural water provision as well as ecological replenishment for river basins along the route. 

Subsequent construction phases for the cross‑provincial water‑transfer infrastructure will now move forward on this newly secured foundation.