Seaweed threat to British sailors' Olympic medal chances

The green algae, covering areas of sea larger than football pitches, is set to make conditions unpredictable in August's Olympic regattas, held off the coast of Qingdao.

Now local fishermen have been ordered to help clear the carpets of seaweed which sailing experts believe would have to be treated as an obstruction during races and would put some crews at a disadvantage.

Blanket: Fishing vessels attempt to clear the green algae

The seaweed is making life hard for those training for the Games, wrapping around keels and stopping boats from getting up to speed.

Britain relies heavily on sailing for Olympic medals and the British Olympic Association's stated target of eight in the medal table would be under threat if sailing events were disrupted.

Iain Percy, a gold medal winner in the 2000 Sydney Olympics, said he was worried by the seaweed's presence, only six weeks from the Games.

He said: "It appeared in patches the size of football pitches which are impossible to sail through.

"How the organisers are going to be able to set a mile-long sailing course is a real cause for concern."

Going green: Workers bag up the seaweed but there's plenty more to do

One theory on the origin of the problematic phenomenon is it is a result of  high levels of pollution.

China's economic boom has resulted in increasing levels of pesticides and fertilizer entering the country's waterways, providing a food source for the algae.

Recent flooding caused by typhoons has also been blamed but Chinese officials have denied pollution is behind the problem.

Big problem: The seaweed is causing a headache for officials in Qingdao, East China