The picturesque seaside city in northern China's Shandong province had been embarrassed by the unsightly algae that left swathes of offshore waters green and disrupted training for a number of Olympic sailing teams ahead of next month's Games.
"The sailing event, which will be held in more than 20 days, will not be threatened by the algae," the official Xinhua news agency quoted Wang Wei, vice president of the Qingdao Sailing Committee, as saying.
Qingdao had set itself a deadline of July 15 to clear algae from the sailing competition area, prompting a massive deployment of ships and troops to scoop the green muck off beaches and offshore. Sailing events are scheduled to start on August 9.
More than 1,400 boats and 10,000 troops and volunteers were dispatched to help clean-up efforts at one stage, and 1 million tonnes of algae had been cleared, Xinhua added.
Two barriers have been installed to keep algae from the sailing venues and ships will also monitor the area, Xinhua said.
The amount of algae on local beaches had visibly shrunk, residents reported, and sailors, who late last month were tacking to avoid large clumps of floating weed, said the algae was no longer a problem in training areas.
"There's so little algae out there now that I really don't think it'll be a problem," said Morgan Reeser, a coach with the British sailing team.
Qingdao authorities warned officials not to be complacent, however, and to be ready to attack further outbreaks.
"We cannot slack off for even a second. We must strive for victory and keep clear-headed at this time," a notice on the city government's website (www.qingdao.gov.cn) said.
Algae blooms regularly blight the shores of Qingdao, where Chinese tourists flock in their millions, but local residents say the current bloom is the biggest they have ever seen.
Officials have been at pains to cast the algae bloom as a harmless natural phenomenon, but local residents and scientists have expressed skepticism, blaming industrial pollutants and agricultural run-off for feeding the bloom.
(Reporting by Ben Blanchard and Ian Ransom; Editing by Ken Wills)
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