The Harbour Area Treatment Scheme is an overall sewage collection and
treatment scheme for areas on both sides of Victoria Harbour.
Construction of this world-class sewage treatment infrastructure is being
carried out in several stages.
Completion of Stage 1 was a major achievement and rising pollution levels
from sewage entering Victoria Harbour have been arrested for now. In fact,
water quality in the Harbour substantially improved when Stage 1 was fully
commissioned at the end of 2001.
Stage 1 of HATS involved the construction of a 23.6 km-long system of
tunnels deep underground, each day carrying 1.4 million tonnes of sewage
from Kowloon and the northeastern part of Hong Kong Island to a chemically
enhanced primary sewage treatment plant at Stonecutters Island.
The opening of Stonecutters Island Sewage Treatment Works, in 1997, was
a major achievement in itself. One of the largest and most efficient plants
of its type in the world, it has recorded outstanding results since its
These sewage treatment milestones have bought us some time by treating
75% of the Harbour sewage, but much more needs to be done to restore the
Harbour to a more natural, healthier, condition.
This is where the next
stage of HATS comes in. The Government has developed a two-phase programme which will provide additional facilities to convey
all sewage from the Harbour area to Stonecutters Island for chemical treatment
and disinfection, and subsequent biological treatment.