Pfft! Just-opened bypass air system breaks downTop News | Charlotte Luo 10 Apr 2019
Part of a HK$250 million air-purification system installed in the Central-Wan Chai Bypass has broken down just a month after it opened, says the Highways Department.
The system is to purify the tunnel exhaust before discharge via the three ventilation buildings. It is the first air-cleaning tunnel system in Hong Kong.
The air-purification system facility in the east ventilation building has been closed since the end of February after seven out of its 15 fans were found with damaged blade edges or broken and loosened bolts.
"The department preliminary suspected that the failure of the mounting bolts was due to problems in the re-installation of bolts when the contractor carried out adjustments to the fan blades," a spokesman said.
"The edges of some fan blades were also damaged as a consequence of some loosened bolts."
Its contractor is a joint venture of Leighton Contractor (Asia).
Leighton is the main contractor at the center of a controversy over the Sha Tin-Central Rail Link construction.
Luk Wai-hung, project manager for the department's major works project management office, described the incident as "rare."
The two other air-purification system facilities - for the middle ventilation building and the west ventilation building - as well as the tunnel smoke extraction and ventilation system, are operating normally.
He said the air quality inside the tunnel is not affected.
The consultant of the bypass project, AECOM, has been monitoring the air quality outside the eastern portal and in the vicinity.
"The air quality monitoring results show no abnormalities in the recent air quality within the tunnel and in the vicinity of the eastern portal," the department said.
The fan components for replacement were shipped from overseas and have arrived in Hong Kong.
The repair is expected to be completed by the end of the month.
Samples of the damaged bolts and blades will be tested by a local laboratory and also the overseas fan manufacturer.
Luk estimated the investigation will take about two months.
The department has submitted a report to the Environmental Protection Department.
The loosened and damaged bolts and blades were spotted by the contractor during an efficiency test of the air-purification system at the end of February. The Highways Department was notified on March 5, but the discovery was not announced until yesterday.
Luk said it takes time for the department to examine the fans and find out the cause, admitting there is room to improve notification.
Civic Party lawmaker Jeremy Tam Man-ho condemned the Highways Department for hiding the incident for this long. Tam said staff working at the bypass or motorists may inhale the exhaust, which could be dangerous and even cause accidents.
Wan Chai District Councillor Jennifer Chow Kit-bing said residents near the exhaust vent from the bypass worry the air quality will deteriorate.
She asked the government to offer more evidence to show the air quality is not affected.
The HK$36 billion bypass, which took almost a decade to build, partially opened on January 20 before fully launching on February 24.