China's lakes and rivers have seen significant improvement in water quality over the past three years thanks to the promotion of a "river and lake chief" system, officials from the Ministry of Water Resources said on Wednesday.

The innovative water resource management system, established in 2018, assigns government heads to take charge of protecting waterways in their area, with the aim of managing water pollution and improving water quality.

The country has about 300,000 river and lake chiefs at the provincial, city and county levels and they conduct 7 million patrols of rivers and lakes each year, Vice-Minister of Water Resources Wei Shanzhong said.

The system has helped limit the use of water resources in rivers and lakes, with strict regional regulations implemented, he said.

Water consumption per 10,000 yuan ($1,570) of GDP, an indicator of water use efficiency, has dropped from 81 cubic meters in 2018 to 57.2.

The launch of the system has led to significant improvements in water quality in lakes and rivers.

Last year, 83.4 percent of surface water across the country was found to be Grade III or above－relatively good quality－up by 15.6 percentage points from 2016, the ministry said.

Since the system was launched, about 185,000 irregularities, such as arbitrary occupation, mining, dumping and construction, have been addressed, said Chen Dayong, deputy head of the ministry's department of river and lake management.

The system has helped to clear more than 4,000 hectares of illegal construction, some 30,000 kilometers of illegally occupied banks, more than 40 million metric tons of garbage in rivers and over 10,000 km of illegal dikes, Chen said.

"The lakes and rivers' flood diversion and storage functions have been greatly strengthened, and the country's aquatic ecosystem has witnessed sustained improvement," he said.

The system has gained increasing public support over the past three years, with nearly 7 million volunteers across China joining campaigns to safeguard the country's rivers and lakes.

In the next five years, Wei said the ministry will continue to give better play to the role of local government and encourage joint protection measures by different regions and departments.

He encouraged river chiefs and lake chiefs to establish a conference system to tackle environmental problems along the same river or in the same lake.

"Solutions in each section should be made to protect a river or a lake as a whole," he said.

"We will complete related laws and regulations and treat the environmental problems of rivers and lakes with comprehensive plans that consider not only the river or lake as a single part but also their surrounding areas," he said.