Koi fish are released into West Lake to test the water quality in September.—VNA/VNS Photo Thanh Dat

The Japan Environment and Trade Promotion Organisation (JETRO) will undertake the treatment of odour, water and mud in the pool.

The committee asked the organisation to send a dossier of technical standards related to the technology, a certificate of processing technology, accredited by the Government of Japan and several documents to the construction department.

The move came after the Japanese nano-bioreactor technology, applied to a section of Hanoi’s polluted To Lich River and West Lake since May, initially showed positive results.

Results released on October 30 said the noxious odour and level of mud in the To Lich River and West Lake have decreased dramatically since nano-bioreactor technology was applied.

The mud on the riverbed has fallen from 91.3cm to 15cm. In West Lake, the level reached zero. The quality of water where Koi fish have been released has met all 36 Vietnamese standards. The bad odour from the To Lich River and West Lake also sharply reduced.

Based on the results, the committee highly appreciated the proposal of piloting treatment to clean a section of To Lich River and a corner of West Lake using the nano-bioreactor technology.

However, chairman of the People’s Committee Nguyen Duc Chung said during the treatment of water in To Lich River and West Lake, the organisation did not follow requirements of the city. For example, it invited press agencies to report on the treatment process when the final results had yet to be revealed.

Therefore, this time, the committee asked the organisation to strictly follow the city's regulations. Especially, the organisation was required to not disclose information related to the treatment process before authorised agencies evaluated the results of the treatment.

It was told to take samples of air, water and mud before, during and after treatment to test against Vietnamese technical standards.

The organisation had to invite independent units that had enough capability to verify the result of the treatment process, the committee said.

After the treatment process finished, a workshop, with the Japan Embassy in Vietnam, international and domestic experts to assess the results would be organised, the committee said.

Previously, on October 30, Minister of Natural Resources and Environment Tran Hong Ha led the ministry’s experts to visit West Lake to inspect the results of the Japanese water treatment technology.

He said the technology was good because it could treat mud in the lake without having to dredge it. Ha added the ministry was considering adapting the technology for Vietnamese wastewater treatment.

Environment Minister checks on To Lich River cleaning project

Minister of Natural Resources and Environment Tran Hong Ha has visited the site and checked the water treatment project at the To Lich River.

Japanese Koi fish released into Hanoi's To Lich river and West Lake to test for clean water

Both Koi fish and carp fish have been released by Japanese experts and Vietnamese scientists into areas of the To Lich river and West Lake that have been treated for pollution as a demonstration of how clean the water is.

Hanoi debates measures to clean up To Lich River

The use of millions of cubic metres of water from the Red River to supply West Lake and clean the polluted To Lich River has been the cheapest and best way to clean the latter river so far.

VNS