The Replacement & Rehabilitation Programme of Water Mains will be completed in 2015, Secretary for Development Carrie Lam says, adding 460km of water mains have already been finished with 890km in progress.

She told the Legislative Council today the four-staged programme will replace and rehabilitate 3,000km of aged mains to enhance water supply, and reduce wastage, nuisance and economic loss due to pipe bursts.

The programme launched in 2000 and works for the first two stages have started while the remaining two will start later this year and in 2011.

Mrs Lam said the works must be done progressively to avoid serious traffic disruptions and public inconvenience.

There were 3,890 incidents of fresh- and salt-water cuts caused by aging mains or components in the last three years.

The Water Supplies Department has formed guidelines to examine each supply suspension or serious traffic disruption due to pipe bursts or component failure.