Efforts will be intensified to promote water conservation as well as the sustainable use of the precious resource, and the task will be a multi-trillion yuan national priority, a central policy document said.

The country will invest 4 trillion yuan ($608 billion) into projects during the next decade to improve water conservation, Chen Xiwen, director of the office for the Communist Party of China (CPC) Central Committee's Leading Group on Rural Work, said on Sunday.

He made the remarks at a news conference held by the State Council Information Office on Sunday, a day after the CPC central authorities issued their first document of the year on Saturday.

The country aims to double its average annual spending on water conservation over the next 10 years compared to the 200 billion yuan investment in 2010, according to the document, also known as the No 1 document.

The government will also encourage loans to, and private investment in, the water sector to ensure funding for conservation, it said.

The CPC Central Committee and the State Council regularly release the No 1 document at the beginning of each year to address government priorities.

This is the eighth consecutive year that the No 1 document has addressed rural issues, but it is the first to focus on water conservation.

"Floods and drought in recent years have exposed weaknesses in water conservancy infrastructures," the document said, citing severe drought in Southwest China as well as severe flooding and mud-rock flows in many regions last year.

The document also said more efforts would be made to improve water quality and farmland irrigation, such as increasing areas under irrigation by 2.7 million hectares over the next five years.

Consequently, up to 10 percent of local land transaction fees should go to farmland irrigation projects, the document said.

Based on last year's total land transaction fees, this figure is expected to be about 60 to 80 billion yuan, Chen Lei, Minister of Water Resources, told the news conference on Sunday.

Li Maosong, a researcher who specializes in disaster-reduction work at the Chinese Academy of Agriculture Science, said the development of water conservation is a long-term goal.

He said the primary task is to fully assess farmland in the country to identify specific irrigation needs.

Other points addressed in the document include:

The country aims to build effective flood control and drought relief systems by the end of 2020.

The harnessing of major medium- and small-sized rivers will be completed during the 12th Five-Year Plan (2011-2015).

The country aims to maintain annual water consumption at below 670 billion cubic meters in the next five years.

The central government will subsidize the maintenance of public benefit water projects in western regions and poverty-stricken areas.

The problem of water not safe to drink in rural areas will be eradicated by the end of 2015.