"Construction waste" means any substance, matter or thing which is generated as a result of construction work and abandoned whether or not it has been processed or stockpiled before being abandoned. It is a mixture of surplus materials arising from site clearance, excavation, construction, refurbishment, renovation, demolition and road works.

Over 80% of construction waste are inert and are known as public fill. Public fill includes debris, rubble, earth and concrete which is suitable for land reclamation and site formation. When properly sorted, materials such as concrete and asphalt can be recycled for use in construction.

The remaining non-inert substances in construction waste include bamboo, timber, vegetation, packaging waste and other organic materials. In contrast to public fill, non-inert waste is not suitable for land reclamation and subject to recovery of reusable/ recyclable items, is disposed of at landfills.

The Problem

Disposal of public fill at public filling areas and mixed construction waste at sorting facilities or landfills has been the major approach for construction waste management. For sustainable development, we can no longer rely solely on reclamation to accept most of the inert construction waste. As such, the government is examining ways to reduce and also to promote the reuse and recycling of construction waste. Nevertheless, there will still be a substantial amount of materials that require disposal, either at public fill reception facilities or at landfills.

Today, we are running out of both reclamation sites and landfill space. With the current trend, our landfills will be full in early to mid-2010s, and public fill capacity will be depleted in the near future. In 2008, the mixed construction waste accounts for about 20% of the total waste intake at the three existing landfills. If there are insufficient public fill capacity and waste reduction measures being implemented, more public fill would probably be diverted to landfills and the landfill life will be further shortened.

(a) Construction waste generated in 2008.
(b) Composition of waste disposed of at landfills in 2008.