The Water Supplies Department has carried out a pilot project intent on reducing water main breakage and leakage by managing the pressure in pipe in selected older districts.
Results of the preliminary tests aimed at reducing water loss have been called "encouraging", said the department. Water supply pressure was adjusted to reduce pressure in pipes, with no affect on household water supply, while at the same time reducing water wastage. The scheme also has no impact on water tariffs.
According to the service pledge of the Water Supplies Department, the pressure level of potable water ranges from 15 to 30 metres, said Vincent Mak, a senior engineer of the department.
In the event that water pressure reaches as high as 60 to 70 metres, owing to geographical factors, connecting points of the water pipes and valves are in danger of rupture, he said. After installation of special pressure reducing valves, the pressure is adjusted to a lower level.
"When people turn on the water taps, they sometimes find the water running very strongly but that is not necessary," he explained. "If water pressure is adjusted to an appropriate level, it will be good enough for the users and save considerable amount of water."
Since the scheme was launched in 2008, the number of leakage reports has decreased marginally, he disclosed. In the past year, fewer than 1,000 cases were reported. There were no more than 200 cases in the first quarter of this year, resulting in a savings of about two million cubic meters of water.
The Water Supplies Department has targeted 17 old districts for launch of the water pressure management scheme, with seven having already gone through the viability study. The cost for each district is about HK$300,000 - a cost that will not be passed on to users.
Mak also said the water pressure management scheme will be extended to all new developments such as the Kai Tak Development Zone as a way to improve the water pressure of the supply network in those areas.