Anti-SARS drainage improvement designs for URA projects
The Urban Renewal Authority (URA) and its joint venture partners
will adopt improved drainage system designs at four residential
projects under construction as a hygiene precaution against
SARS.
Chairman of URA's Planning, Development and Conservation Committee,
Professor David Lung, told a press conference today (Tuesday) that
the URA and its private sector partners, have decided to adopt two
alternative improvement designs known as U-trap Refilling Design
and Pipes Separation Design.
Either one of the designs will be adopted for the four residential
projects which consist of about 4,300 flats in total. The
additional cost for the new designs is estimated at about $2
million.
"This represents only a small fraction of the total development
costs that run into billions of dollars but it goes a long way in
upgrading the hygiene standard of the drainage systems,
particularly for the purpose of SARS prevention," Professor Lung
said.
Earlier, a Government investigation report has revealed that SARS
transmission might be related to the reflux of contaminated air
from the soil stack (connected to water closets) through the
bathroom floor drain. It was suspected that the reflux has occurred
as a result of the drying out of the water seal in the U-trap of
the floor drain.
The U-trap Refilling Design is to connect the discharge pipe of the
water basin to the U-trap of the floor drain so that each time the
water basin is used, the water discharged automatically refills the
U-trap and forms a water seal.
The Pipes Separation Design is to separate the floor drain pipework
from the soil stack so that the contaminated air in the soil stack
will have no chance of flowing across to the floor drain.
The reason that there are two alternative designs is that the
U-trap Refilling Design, which is cheaper at about $150 each, is
compatible only with a certain type of drainage system. On the
other hand, the Pipes Separation Design, which costs about $500
each, is compatible with most drainage systems.
"Both designs are conceptually and technically effective. It is
just a matter of drainage system compatibility when choosing
between the two," Professor Lung explained.
URA's District Development Director, Mr. Stephen Lam, said the URA
would adopt the new designs for all four residential projects under
construction with joint venture partners. They include the Tsuen
Wan Town Centre project, Kennedy Town New Praya project, Waterloo
Road/Yunnam Lane project and Wan Chai Road/Tai Yuen Street
project.
"We intend to adopt these or other drainage improvement designs
also for all future projects to come and we will continue to watch
out for new technology to further upgrade the hygiene standards and
features in our new buildings," he added.