2 PROJECT DESCRIPTION

Project Location

2.1 The proposed Tuen Mun Area 54 sewage pumping station (TM54SPS) is located in the central part of Site 4A of Tuen Mun Area 54, north of Kei Lun Wai, south of Tsz Tin Tsuen and west of Site 2 of Tuen Mun Area 54. The location is shown on Figure 2.1. The proposed development at Site 4A of Tuen Mun Area 54 is shown on Figure 2.1. Site 4A is zoned “Government, Institution or Community” (G/IC) on the Tuen Mun Outline Zoning Plan (OZP) No. S/TM/24 and is reserved for school development. Site 2 is zoned “Residential (Group A)” and Site 3&4(East) is zoned “Residential (Group A)” on the Tuen Mun OZP No. S/TM/24. Public housing will be developed at Site 2 and Site 3&4(East).

Need of the Project

2.2 According to the Review of Tuen Mun and Tsing Yi Sewerage Master Plans, the TM54SPS will receive sewage from the proposed development in Area 54, the four recognized villages within Area 54 namely Tsz Tin Tsuen, Po Tong Ha, Kei Lun Wai and Siu Hang Tsuen, and the proposed Tuen Mun North Sewage Pumping Station in Area 52.

2.3 The TM54SPS at Site 4A of Tuen Mun Area 54 is required to convey the sewage collected from Tuen Mun Area 54 to the existing trunk sewers at Ming Kum Road.

Consideration of Alternatives

2.4 In the Value Management Workshop held in February 2006, it was concluded that the sewage pumping station would be moved to Site 4A which was a relatively low point within the sewerage basin area. This enables the connection of gravity feed sewers from the proposed development in Area 54 and the existing villages. Potential impacts to the nearby residents, maintenance cost, ease of connection to the proposed/existing system and maintenance access had also been taken into consideration.

2.5 During the public consultation, specific locations for the sewage pumping station were proposed, i.e. the alternative locations 1, 2 and 3 as shown on Figure 2.2. All three alternative locations are aligned adjacent to the future Road L54B as shown. The potential environmental impacts, engineering considerations as well as public concern have been taken into account in assessing the alternative locations. The engineering considerations included the following aspects:

• Layout & geometry

• Topography

• Maintenance costs

• Ease of connection to proposed/existing system

• Maintenance access

2.6 A comparison of the three alternative locations with regard to engineering considerations and public views was carried out and the findings are summarized in Table 2.1 below.

Table 2.1 Comparison of Alternative Locations – Engineering Considerations and Public Concern

	Ratings for Location ⁽¹⁾			Findings
	1	2	3	Findings
Layout and geometry	3	2	5	The three locations are similar in size but Location 3 has a more regular geometry. This is more favorable for accommodating the SPS which is in rectangular format.
Topography	4	4	5	Within Site 4A, the lowest point is located at Location 3 (about +6.0 mPD).
Maintenance costs	4	3	3	Location 1 is situated next to the future widened Tze Tin Road which will be constructed in the first phase of the development. The proposed Road L54B which also serves as the access to Locations 2 & 3 will be available at a later stage of the development. Thus, a section of maintenance access is required for both Locations 2 & 3 which will incur additional recurrent costs before the implementation of Road L54B. Recurrent costs for operation and maintenance of the sewers and rising mains are expected to be similar as the pipelines are emerging from both the west and the east directions.
Ease of connection to proposed/ existing system	4	3	4	Location 1 has priority over Locations 2 & 3 for connection of the sewers in Site 2 of the development. However, Location 3 is situated closer to the centre of Area 54 as well as the local villages in a macro perspective. Location 3 has advantage for connection to the proposed system in the long run.
Maintenance access to SPS	4	4	4	All three locations are accessible for future maintenance.
Public concern	1	2	5	During the public consultation to the Tuen Mun Rural Committee and the locals held on 8 March 2007, the public had grave concern on the location of the SPS. Amongst the 3 locations, they objected to Location 1, did not support Location 2 but supported Location 3, as Location 3 is much far away from the village houses nearby.
Total	20	18	26

Note:

(1) Marks are given according to the following ratings:

Poor/ Unsatisfactory	- - - - - - - - - - - -	Acceptable	- - - - - - - - - - - -	Highly favorable
1	2	3	4	5

2.7 All the three locations are feasible and acceptable for accommodating the TM54SPS in terms of engineering considerations. However, Location 3 is more favorable when summing up the grave public concern.

2.8 An evaluation of the environmental impacts of the three alternative locations was undertaken, with respect to the issues of noise, air quality, water quality, landscape and visual and cultural heritage (Table 2.2 refers). Based on the evaluation findings, all three locations are considered to be similar in terms of the potential environmental impacts associated with the construction and operation of the TM54SPS.

2.9 Overall, following the evaluation of engineering and environmental considerations and public concern associated with the three alternative locations, Location 3 is identified to be the preferred location for the proposed TM54SPS.

Table 2.2 Comparison of Alternative Locations – Environmental Considerations

Location	Potential Environmental Impacts
	Noise / Air Quality	Water Quality	Landscape and Visual	Cultural Heritage
1	Location 1 is close to the residential dwellings of Union Garden which represent noise and air sensitive receivers	Location 1 is near the drainage culvert adjacent to Tsz Tin Road. Locations 2 and 3 are near the nullah / drainage culvert adjacent to Kei Lun Wai village. Potential water quality impacts associated with the construction and operation of the SPS would be expected to be similar for the three locations.	Location 1 is significantly to the agri-rural visual character of Farmlands and orchards within the site area, and within close distance to VSR of Tze Tin Tsuen and Traveler on Tze Tin Road. According to Tree survey there is 4 no. of trees will be affected from the works. Landscape and Visual impact on Location 2 and 3 would be similar as they are characterize as Open storage landscape character; however 1 mature tree of Celtis sinensis will be affected by the works in Location 2 comparing with no potential landscape impact on Location 3 Location 2 is close to potential VSRs of Union Garden Location 3 is close to potential VSRs of Kei Lun Wai	All three locations fall within the Kei Lun Wai Archaeological Site. All three locations have no impact to built heritage resources.
2	Location 2 is close to the residential dwellings of Union Garden which represent noise and air sensitive receivers
3	Location 3 is close to the residential dwellings of Kei Lun Wai village which represent noise and air sensitive receivers

Project Description

2.10 The design capacity of the TM54SPS is about 1.03 m³/s. The average dry weather flow is 0.32 m³/s. The schematic layout of the TM54SPS is shown on Figure 1.1.

2.11 The tentative construction activities are shown on Figure 2.3.

Project Programme

2.12 The construction works for the Project are scheduled to commence in early 2011 for completion in early 2014. A tentative construction programme is shown in Figure 2.3.

Interactions with Other Projects

2.13 There are likely interactions with the following projects:

• Sewerage upgrading works in Tuen Mun managed by Drainage Services Department (Agreement No. CE 38/2006 (DS))

• Formation, Roads and Drains in Tuen Mun Area 54 – Phases 1 and 2, Private and Public Rental Housing Development in Tuen Mun Area 54 managed by CEDD (Agreement No. CE 21/2005 (CE))

2.14 The construction programme for Tuen Mun Sewerage (Contracts 3, 4 and 5) is scheduled to commence in mid 2009 for completion in end 2013 tentatively. The construction programme for the Formation, Roads and Drains in Tuen Mun Area 54, and the infrastructural works in Site 2 of Tuen Mun Area 54, is September 2009 to December 2012. The target population intake dates for Site 2 and Sites 3/4 (East) of Tuen Mun Area 54 are March 2016 and May 2019, respectively.