LegCo Panel on Planning, Lands and Works Meeting on 10 December 1998

Agenda Item VII - Sewerage Works in the North District

1. Introduction

1.1 The North District Sewerage Master Plan Study was completed in September 1994. The project was subsequently handed over to DSD for implementation. The recommended works included improvements to existing sewerage systems, extensions of trunk sewer networks, upgrading of Shek Wu Hui Sewage Treatment Works, provision of village sewerage, and some interim measures.

1.2 These sewerage works are part of an overall strategy to protect the Beas, Indus, Ganges and Sham Chun rivers and Deep Bay as well as the relatively unpolluted waters of Starling Inlet and Mirs Bay. We expect that upon the completion of the sewerage connection works, there would be about 20% reduction in pollution loads entering these waters.

2. Investigation Study

2.1 We initiated the sewerage works in the North District by including in Category B of the Public Works Programme at the end of 1994. We appointed consultants in 1995 to carry out an investigation study into the layout design, environmental review, traffic impacts, works programming, costing and contract strategy associated with the implementation of the sewerage works.

2.2 The investigation study involved consultation with the North District Board and the villagers. Extensive site investigation works and other surveys were also conducted. The investigation study was concluded in early 1997 and a copy of Drawing No. DCM 1411A showing the layout of the North District Sewerage is enclosed. The works involve the construction of approximately 13.7km. of trunk sewers, village sewerage to 74 villages, 32 pumping stations, and seven village type sewage treatment works (STW). The total construction cost is $700 Million which will be spent over the project period of seven years from 1999 to 2005.


2.3 The implementation programme is as shown in Appendix I. We shall divide the sewerage works into three packages for implementation, namely, Stage 1 Phase 1, Stage 1 Phase 2 and Stage 2. The programme by itself is very compact after taking into consideration the land availability dates, the volume of works and consultation involved, the sequential development of the sewerage network and the efforts to minimise disturbances to the public. In particular, the length of works programme is dominated by the time required to resume land for the village sewerage works. Of the 74 villages to be sewered, we need to resume land in 51 villages by means of the Water Pollution Control (Sewerage) Regulation. This will normally take six months to process the gazetting procedures and another six to nine months to resolve objections received. After objections are resolved, Lands Department will take about another nine months to clear the land before it can be handed over for works implementation.

2.4 Stage 1 Phase 1 works will cover the western trunk sewer together with the village sewerage for the seven villages within the trunk sewer's catchment. Design and construction supervision will be carried out by Drainage Services Department's (DSD) staff. The estimated cost for Stage 1 Phase 1 is around $190 Million . The recent funding application for the North District Sewerage Stage 1 Phase 1A works discussed at the Public Works Subcommittee meeting on 11 November 1998 is the first part of this package. We have already completed the design for this part. The construction of the western trunk sewer will commence in early 1999 for completion in 2002. The second part of this package (Stage 1 Phase 1B) covers the village sewerage. The works will commence in 2000 and will be completed in 2002 at the same time when the western trunk sewer is commissioned. We shall discharge the sewage collected in this phase to Shek Wu Hui STW through the existing sewerage networks.

2.5 Stage 1 Phase 2 covers the eastern trunk sewer and the village sewerage to 31 villages within its catchment. The estimated cost for Stage 1 Phase 2 is $252 Million. DSD will employ consultants to carry out design and construction supervision of the works. We are in the process of appointing consultants and design will start in early 1999. Construction is programmed to commence at the end of 2000 and to complete by 2004 under five separate contracts. Similar to the case of Stage 1 Phase 1, we shall discharge the collected sewage to Shek Wu Hui STW.

2.6 Stage 2 covers the Pak Hok Lam trunk sewer, the southern trunk sewer, seven village type STWs and village sewerage to 36 villages. The estimated cost is in order of $258 Million. We shall appoint consultants in 2000 to design and to supervise construction of the stage 2 works. Construction will commence in 2003 and will complete in 2005 under four separate contracts. We shall discharge sewage collected from the villages along the southern trunk sewer to Shek Wu Hui STW. Sewage collected from the villages along the Pak Hok Lam trunk sewer will be discharged into Sha Tau Kok STW. For the 17 villages in Ma Tso Lung, Luk Keng and Tsui Keng areas, they are too remote to be connected to the existing sewerage network. We shall construct seven local village type STWs to serve these villages.

2.7 Upon the completion of the main and branch sewers in the villages, individual village house connections could be carried out progressively as early as in mid-2002 and expected to complete in 2005, serving a total population of 62,400 people.

Local Liaison

2.8 Whilst the current programme is very compact, we shall endeavour to expedite it by liaising closely with DLO on land issues and with DO to facilitate public consultation with DBs, the village representatives and villagers. This would help to expedite connection programme of village sewerage, where complex land issues, various engineering practical constraints and a diversity of views from local villagers are often encountered.

Planning, Environment and Lands Bureau
December 1998

i. All costs quoted in this paper are in Dec 97 value.