The scheme to get construction companies to pay for their waste is already paying off, the Secretary for Environment, Transport & Works Sarah Liao says.

Noting that Hong Kong's landfill will be full in less than 10 years, and the Government has made waste reduction one of its key strategies, Ms Liao told ATV's Newsline programme that construction companies will now be more active in recycling and reusing construction waste.

On the use of Hong Kong construction waste as landfill on the Mainland, she said: "We have a memorandum of understanding. If they have reclamation to do on the other side of the border, they should use the waste we generate rather than opening up some mountains and destroying the environment further."

Referring to the $20 billion sewage treatment scheme to clean up the Victoria Harbour, which is currently under public consultation, she said for Hong Kong to be a world class city the waste water pumping into the harbour must be treated.

She also said the two local electricity companies have agreed to build commercial scale windmills to test the viability of this energy source in Hong Kong.