BEIJING, June 8 -- China will build and upgrade around 770,000 km of urban underground pipelines during the 15th Five-Year Plan period (2026-2030), an official said Monday.

The country currently has some 3.9 million km of such pipelines and around 7,700 km of integrated utility tunnels, Chen Shaopeng, an official with the Ministry of Housing and Urban-Rural Development, told a State Council policy briefing.

According to Chen, the initiative will focus on improving drainage and sewage networks to strengthen flood control, replacing aging water and gas pipelines, and upgrading heating systems to improve safety and efficiency.

Smart monitoring systems will also be installed to enable full-process risk management of urban infrastructure.

Guan Peng, an official with the National Development and Reform Commission (NDRC), said at the briefing that the NDRC and the ministry have actively supported underground pipeline projects through ultra-long special treasury bonds.

A total of 160 billion yuan (about 23.5 billion U.S. dollars) will be earmarked for these projects in 2026, an increase of 25 billion yuan from the previous year, Guan added.