But their complaints are flicked from one department to another. In some cases, they wait up to two years to get the problems fixed.

The four authorities handling the complaints are the Building Department, the Food and Environmental Hygiene Department (FEHD), the Water Supplies Department and the Home Affairs Department. Each authority only deals with the complaints when they fall into their area.

For example, the Buildings Department takes up a case when the water leakage causes structural safety problems, while the Water Supplies Department will take action when the seepage results in serious wastage. The Home Affairs Department sometimes takes part in inter-departmental liaison.

Last year, the Buildings Department alone received 6,400 complaints about water leakage, while 1,680 were filed to the Water Supplies Department.

The FEHD after receiving a complaint, puts dye in the drainage system to find the source.

But of 798 complaints the FEHD's Central and Western district office received from May last year and April this year, 766 tests failed to identify the source of the problem. Only 32 cases were traced back to damaged water pipes.

Yeung Wai-foon, Central and Western district councillor, said many residents, especially those living in old buildings, suffer water leakage from upstairs.

'Water pipes in old buildings are ageing, which causes water dripping into flats,' he said.

The Central and Western District Council has called for streamlined processing of complaints.

Mr Yeung said the departments failed to consider a flat owner's point of view making it difficult to handle complaints. 'The complaints are being thrown from one government department to another department,' said Mr Yeung. He said the most difficult task was to resolve conflict among the residents. 'They [residents whose flats leak] refuse to let people ... inspect the defects because they are afraid this will get them into trouble,' he said.

He said high legal costs also deterred cases being taken to court.

Johnny Chan Wah-tim, of the Home Affairs Department, told the District Council last week that the Building Department and the FEHD will 'actively study' the plan for a new one-stop office this year.

But Mr Yeung was pessimistic about the plan. 'I don't think the government has the resources to do it now,' he said.

Wtaer torture

How government departments deal with leakage cases

Home Affairs Department

It transfers complaints to the Food and Environment Department

Food and Environmental Hygiene Department

If it can't find the source of the leak, it transfers the complaint to the Building Department and Water Supplies Department. If the leak affects hygiene, it will issue a notice requesting repairs. Parties can be prosecuted and fined up to $10,000

Building Department

It has a performance pledge to screen and inspect the site within 50 days. If the flat owner does not act, the department can take legal action

Water Supplies Department

If the leak leads to serious wastage, and the owner refuses to make repairs, it can cut the water supply