Hanoi to clean up famous Hoan Kiem Lake after sacred turtle's death

Hanoi Vietnamese authorities will dredge Hoan Kiem Lake, one of Hanoi's main tourist attractions, in a bid to clean up severe pollution threatening wildlife.

The dredging will clean 57,400 cubic metres of mud from the lake by the year's end, the online newspaper Vietnam Plus reported on Thursday.

The lake was home to Cu Rua, or Great-Grandfather, which was the last Yangtze giant soft-shell turtle of the rafetus leloii species before it died last year.

Considered a symbol of Vietnam's independence, Cu Rua may have lived for centuries in the lake, although its precise age was unknown.

Turtles have long been linked to Hoan Kiem. Thap Rua, or Turtle Tower, which rises from an island in the middle of a lake, has been linked to the myth of an emperor who used the magic sword of a golden turtle god to lead a revolt against the Chinese.

The lake is one of many in the Vietnamese capital, but is notable for its tree- lined banks as well as the Ngoc Son Temple, or Temple of the Jade Mountain, which sits on an island at its southern end.

Hanoi authorities will spend about 29 billion Vietnamese dong ($A1.7 million) from the city's budget to carry out the work, the report said.

The dredging will take place seven nights per week to avoid disruption. It has been scheduled to finish by the middle of February, 2018.