ENG-2007 — Page 327

The Environment | 275

Intruder Alarm and Neighbourhood Noise

The Police handles complaints about intruder alarms and neighbourhood noise from domestic premises and public places. In 2007, the police dealt with some 1 800 complaints.

Water Quality and Sewerage

Water pollution has increased with urban development and population growth, and Hong Kong now produces about 2.8 million cubic metres of sewage every day. In the past, the lack of proper treatment for most of the sewage from older urban areas around Victoria Harbour resulted in poor water quality there but, after the first stage of the Harbour Area Treatment Scheme (HATS) went into operation at the end of 2001, there has been a marked improvement. The Government is taking steps to implement the second stage of the scheme soon, to ensure that the improvement is sustained.

In addition, pollution control at source has yielded positive results, and river quality has also improved. The percentage of rivers in the 'good' and 'excellent' categories increased from 34 per cent in 1986 to 81 per cent in 2007, and the percentage in the 'bad' and 'very bad' categories fell from 45 per cent in 1986 to 10 per cent in 2007.

Sewage Treatment and Disposal

At present, the public sewerage system serves 93 per cent of the population and collects about 2.6 million cubic metres of waste water every day. About 70 per cent of the collected sewage receives chemical or higher levels of treatment before being discharged.

During the first stage of the HATS, sewage was collected from the urban areas of Kowloon, Tsuen Wan, Kwai Tsing, Tseung Kwan O and the northeastern part of Hong Kong Island and transported through a network of deep tunnels to Stonecutters Island for treatment.

The Government will implement the second stage in two phases. The first phase (HATS Stage 2A) involves extending the deep tunnel system to take the untreated sewage from the remaining parts of Hong Kong Island to the Stonecutters Island Sewage Treatment Works. The treatment plant is to be expanded to provide centralised chemical treatment for all sewage from the whole of the HATS catchment with fast-track provision of part of the disinfection facilities in 2009. The design works for the HATS Stage 2A are now well under way and the target year for completion of this phase is 2014. Under the second phase (HATS Stage 2B), new biological treatment facilities on a site adjacent to the existing Stonecutters Island Sewage Treatment Works will be built. The timing for this will be decided based on the results of a review in 2010-11 of water quality trends as well as the population and sewage flow build-up.

More details of the HATS are available on the 'A Clean Harbour for Hong Kong' website, www.cleanharbour.gov.hk.