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Wednesday, January 11, 2017, 09:06

A reflection on pure water

By Willa Wu

Picturesque Wanlyu Lake in Guangdong provides up to 40 percent of Hong Kong’s fresh water supply. It’s a responsibility that has come at considerable cost to nearby Heyuan City. Willa Wu reports.

A reflection on pure water

Heyuan, in northeastern Guangdong province, is tranquil and picturesque, surrounded by an evergreen forest. It is a city of squat buildings and light traffic, with a river running through downtown, giving off pleasant freshness, to the Wanlyu Lake in the rural area.

In sharp contrast to most cities in the province, Heyuan has seen its economy stagnate, passing up lucrative development projects, all in quest of maintaining pure fresh water from the nearby Wanlyu, one of the principle fresh water sources for Hong Kong.

“Protecting the lake is the city’s top priority,” said Gong Zuolin, chairwoman of the Heyuan Municipal Committee of the Chinese People’s Political Consultative Conference (CPPCC). She added that the authority believes “green hills and clear waters are as precious as gold in contributing to the city’s development in the long run.”

Some 3.6 miles from downtown Heyuan, Lai Jinsong sets out in a boat on Wanlyu Lake. Lai is the deputy of the Wanlyu Lake Environmental Supervision Branch. His job is to oversee the lake which supplies nearly 40 percent of Hong Kong’s fresh water.

Lai seldom gets to travel to Hong Kong — but he is the man who plays a hefty role in maintaining the purity of the city’s fresh water supply. “I hope Hong Kong people know how much we have sacrificed and how hard we try to guarantee the water quality,” said Lai.

Wanlyu in Chinese means “evergreen”. The lake earned its name from the surrounding environment and from the water which remains clear all year round. China Daily took a 30-minute boat trip around the lake. In sight, the sun bounced on the lake’s calm. The reflections of the trees at the water’s edge added an aquamarine hue to the water. Even the surrounding air smelled fresh and pleasant in the afternoon breeze.

Also known as Xinfengjiang Reservoir, Wanlyu Lake is the largest man-made lake in Guangdong province with a water storage capacity of 13.9 billion cubic meters.

Wanlyu Lake provides half of the fresh water from the Dongjiang-Shenzhen Water Supply Project. The project has two sources, Wanlyu Lake and the Dongjiang River. The project is the source of the greater part of Hong Kong’s water supply, the SAR’s guarantee of a stable fresh water supply since March 1965. It’s often called Hong Kong’s lifeblood. 

Twice a week, Lai patrols the lake with a team of technicians, collecting water samples all over the lake, then sending them to be checked out in a lab. Once the water samples fail to meet the criteria for Hong Kong’s drinking water, Lai and his team would set out to trace pollutants that may have caused that.

A reflection on pure water

Rigorous monitoring system

Lai described the search as the “only excitement” on his job, which he has been doing for nearly six years. According to him, the “excitement” usually means days of search in surrounding forests and villages, with no advanced research tools, only the native powers of human perception.  

“I take pride in the water we send to Hong Kong. It is of supreme quality,” Lai said. He continued that the general water quality of Wanlyu Lake is at the Class II national standard for drinking water. In some parts of the lake it reaches Class I.

According to China’s drinking water standards, water that reaches Class III is still potable. The top three levels are classified as premium quality drinking water, from first class protected areas or national nature reserves. “Water of Class I can be drunk directly without being processed,” Lai explained.

Craspedacusta, a kind of freshwater jellyfish that’s called “panda in the water”, has been found inhabiting some parts of Wanlyu Lake. The jellyfish, with 550 million years of history, survive only in water that is free of pollution.

The work is done only by Lai and his five team members. There is one big headache, “My team is short of hands,” he said.

“We do more than just sitting on a boat. Water samples are collected five meters and 10 meters from the surface respectively and from different parts of the lake. Back from the patrols, we need to do quality checks on the samples. If the water quality does not meet the Class II criteria, we have to investigate the causes,” Lai said.

The causes of pollution are often related to illegal private mining. Heyuan is a mineral-rich city with 32 kinds of mineral resources. Among them, iron ore deposits take the lead, with the reserve volume reaching 276 million tons, accounting for 39 percent of Guangdong’s total iron ore deposits.

Small mine workshops, usually family-run, without approval from the municipal government, illegally exploit the city’s iron-ore deposits. These operations often hide deep in the forest. It usually takes days, even weeks for Lai’s team to locate them.

A reflection on pure water

Worthy sacrifice

Protecting water quality is a profoundly important project that requires multiple efforts, as well as a great deal of money. Besides allocating Lai’s department an annual funding of 30 million yuan (HK$33.5 million), the city’s municipal government also spends money in ensuring no domestic wastewater goes to the lake. Heyuan CPPCC chairwoman Gong told China Daily that the government has so far invested 30 million yuan to clean up houseboats on the lake, relocating around 1,000 people back to houses on land.

In addition, the city also strives to expand urban green areas. The forest cover reached 74.3 percent in 2015, with 16.8 percent of the city’s land occupied by nature reserves.

“The green areas in the city help to curb acid rain which would seriously contaminate Wanlyu Lake. And the work to remove acid is intensive,” said Lai. Heyuan is the only city in Guangdong that experiences no acid rain throughout the year.

All this effort has come at heavy cost for the city that has turned down 300 investment projects which posed potential pollution threats to the lake. About 4,700 mines were closed in the interests of environmental protection. The cost of those measures to protect the water brought a decrease of 50 billion yuan in the city’s GDP, Gong said.

Data from Heyuan Statistics Information Network show that the city’s GDP in 2015 totaled around 81 billion yuan, accounting for only 8 percent of Guangdong’s provincial GDP. While the annual per capita GDP of Heyuan reached only 26,401 yuan, half of the provincial average.

Gong said despite the economic setback, the city was doing “a right thing”. “In order to send good quality water to Hong Kong people, Heyuan has no complaints or regrets in turning down profitable business,” she added.

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