BEIJING,Dec. 16,2024 -- A report from China Daily

Drone footage of the Danjiangkou Reservoir. Danjiangkou strengthens the construction of information technology for reservoir water quality security,establishing a protection system in all aspects of "sky,land,space,and water". Photo provided to China Daily

The Danjiangkou Reservoir in Central China's Hubei province is the water source for the middle route of the country's South-to-North Water Diversion Project.

Over the past 10 years,the reservoir has delivered about 68 billion cubic meters of clean water,benefiting more than 100 million people in 26 cities across the country.

Specifically,it has supplied more than 20 billion cu m of water to Hebei and Henan provinces,and about 10 billion cu m to Beijing and Tianjin. To date,Tianjin has full coverage of southern water,while 11 provincial cities in Henan and more than 90 counties in Hebei have switched to the southern water source.

Zhang Shuguang,deputy chief of the water resources and water conservation department of Langfang in Hebei,said that following the completion of the middle route of the South-to-North Water Diversion Project,the city has shut down more than 12,000 water wells,replacing water sources and replenishing groundwater. As a result,its rivers and lakes have become vibrant.

Currently,seven counties and districts in the southern part of Langfang have started using southern water,and water supply projects now under construction in Sanhe city,Xianghe county and Dachang Hui autonomous county are expected to be completed and operating by the end of 2025.

In Hanying village,Dengzhou city,Henan province,76-year-old villager Han Qingzhou finishes his farm work and goes to the village committee carrying a teapot.

At the committee's public hot water dispenser,Han adds a small amount of tea leaves to the pot,pours in boiling water,and the fragrance of tea fills the air. "Since 2014,after using water from the Danjiangkou Reservoir,water purifiers have become obsolete," Han said.

For many years,the village relied on well water,which was hard and had a high mineral content. Every household in the village used water purifiers,costing around 4,000-5,000 yuan ($550-690) per set. In 2014,a drinking water plant was built in the village. Now when taps are turned on,water from Danjiangkou flows out. The brewed tea tastes sweet and refreshing,rendering water purifiers unnecessary.

Built in the early 1980s,the Ya'an Dongli community of Jialingdao Street in Nankai district,Tianjin,has 2,018 households and 688 residents,many of whom are elderly or disabled.

The residents,Qiu Heyi and Zhang Limin,feel grateful for the benefits brought by the southern water. "We've been using this kettle for nearly 10 years and there's no mineral buildup," Zhang said.

Due to the aging infrastructure in the community,with many pipes corroded and water quality issues,residents had a substandard living experience. To improve the water supply conditions for the residents,Tianjin conducted free household pipeline renovations in 2012. In 2015,local residents began using the southern water from the Danjiangkou Reservoir in Hubei.

"After the switch,everyone felt much better. The rice cooked with this water tastes amazing," Qiu said.

In recent years,Baiquan Lake,with a history of more than 3,000 years,has become a popular spot for tourists in Huixian,Henan.

The lake is named after the 400-plus springs gushing from its bottom. With the decline in groundwater levels,Baiquan Lake began intermittently drying up in the 1970s and 1980s. After a brief resurgence in 2003,the springs ceased to flow. Consequently,the lake's bottom was used for acrobatic and equestrian performances.

Following the arrival of southern water,residents now have secure access to water. Local authorities have also implemented plans to reduce groundwater extraction,leading to a rise in groundwater levels. In 2021,after an absence of 18 years,Baiquan Lake once again exhibits the stunning sight of gushing springs.

Local photography enthusiast Han Xiuping said now there are fish in the spring water and birds foraging on the lake and wetlands.

According to water authorities,since 2018,groundwater levels in Huixian have risen by 4.6 meters,gradually restoring the ecological functions of rivers and lakes.

Rising groundwater levels

Groundwater is an invisible yet valuable resource,possessing ecological attributes. The rise in groundwater levels not only enriches water reserves but also mitigates subsidence issues,preventing potential ground sinking and promoting economic and social development.

Cities along the route have utilized the southern water,reducing or halting groundwater extraction,facilitating groundwater replacement and optimizing the water resource allocation pattern.

For example,Puyang in Henan is situated in the largest groundwater funnel area in North China,where over-extraction of groundwater covers 88 percent of the total area. In 2021,Puyang became the first in the country to establish an integrated urban-rural water supply network,providing the city's 3.7 million residents with the same high-quality water from the south. By 2023,groundwater levels in Puyang rose by 1.53 meters compared to 2022,maintaining an upward trend for 25 months.

In 2022,the water replacement project for water sources in rural areas in Dingzhou city,Hebei,was initiated. It converted 402 villages,922,600 residents,and 537 enterprises to southern water from groundwater. After the project's implementation,415 rural groundwater wells were closed in the city,reducing groundwater extraction by 26.77 million cu m annually.

In Beijing,the arrival of southern water has reversed the 16-year trend of declining groundwater levels. According to the latest data from the city's water bureau,as of Oct 28,the average burial depth of groundwater in the plain areas of the city is 12.41 meters,marking the ninth consecutive year of rising groundwater levels.