China is reported to be close to giving the go-ahead to a controversial scheme to pump huge amounts of water from its flood-prone south to the drought-afflicted north.

Consensus has been reached on all aspects of the project

Zhang Jiyao

An official newspaper said workers were waiting for a green light from the central government to start the scheme, described as the most ambitious water diversion project in China's history.

Critics have raised concerns about the project, which is even more expensive than the controversial Three Gorges Dam.

The project was first proposed in 1958, but it has taken engineers and planners over 40 years to decide how to build channels needed to carry 48 billion cubic metres of water per year from north to south.

Three channels, each over 1,000 kilometres long, will be built connecting the Yangtze with the Hai, Huai and Yellow Rivers in northern China.

The eastern channel, the easiest technically and the cheapest with a projected cost of around $7bn, will largely use existing watercourses including the old imperial Grand Canal.

Water shortage

The central and western routes will require the construction of vast lengths of canals, aqueducts and tunnels, including a tunnel under the Yellow River to carry water further north.

The vice minister of water resources, Zhang Jiyao, said consensus had now been reached on all aspects of the plan.

A senior official at one of the companies involved in the project ruled out suggestions that the transfer could leave areas along the way with not enough water.

That is only one of the issues that have been raised surrounding this plan.

It is even more expensive than the Three Gorges dam being built further west on the Yangtze river, which has already displaced hundreds of thousands of people from their homes.

Critics have expressed concern about work starting on the new project when such problems as cracks in the dam and toxic waste at the Three Gorges site have yet to be resolved.

And some Chinese politicians have been reported as complaining about a lack of debate over the water transfer scheme in the country's parliament, the National People's Congress.

But the time for that may now be past.

The official China Daily newspaper said on Monday that workers were now waiting for the signal from the central government to break ground on the project.