QINGDAO -- Troops, fishermen and volunteers continued to clean up the seawater at the Olympic sailing venue in Qingdao on Tuesday as the density of the green weed shrank to 1.37 percent from 32 percent over the past 10 days.

As of Monday afternoon, the coverage of algae in the 49.48-square-kilometer Olympic sailing venue was reduced to 0.679 square kilometers, according to the North China Sea Branch of the State Oceanic Administration.

Ten days ago, on June 28, 15.86 sq km of the guarded sea area was covered by algae.

"As the algae bloom has subsided, most cleaners are still 'searching' for algae," said Wang Yiqiu, an official with the Qingdao oceanic and fishery bureau.

In the past two weeks, more than 130,000 soldiers and volunteers worked furiously at the site, removing more than 50 tonnes of algae from the water.

Wang himself works at least 10 hours a day, patrolling on the beach and shouting into his walkie-talkie to despatch some 500 fishing boats within his jurisdiction to clean up newly detected algae bloom in the Olympic waters.

Altogether 2,085 vessels were at work on Monday, searching and removing algae. Fishermen who had been seasonally laid off by the summer fishing ban were now to be paid by the government for their new job, said Wang.

"Most of these vessels will be standing by throughout the sailing event for potential algae blooms during the Games," he said.

The sailing competitions are scheduled for August 9-23.

On Tuesday, workers are set to complete a 32,000-meter enclosure in the sea to keep algae out of the venue. About half of the enclosure was completed as of midday on Monday.

The Qingdao government has vowed to clear up the sailing event venue before July 15.

VOLUNTEERS AT WORK

Zhao Shumei, 81, is probably the oldest algae-cleaning volunteer in Qingdao.