LANZHOU, Dec. 9 (Xinhua) -- Northwest China's Gansu Province has upgraded the drinking water supply for more than 12.51 million residents, including 1.66 million living in poverty, since 2016, local authorities said.

In the past five years, Gansu has invested a total of 10.55 billion yuan (around 1.62 billion U.S. dollars) to provide clean and safe drinking water for residents, especially those in rural areas, said Wang Jianghai, an official with the provincial water resources department.

The funds were mainly employed in the upgrading of 50,561 water supply projects, the renovation of 8,281 km of frozen pipes, and the installation of 39,900 sets of water purification equipment in the province, Wang noted.

The centralized water supply coverage and the penetration rate of tap water in rural areas in Gansu have reached 91 percent and 88 percent, respectively, both higher than the national average, Wang added.

Gansu has hired more than 20,000 rural residents and set up a 24-hour provincial-level supervision and complaint hotline to strengthen rural water supply management.