2. DESCRIPTION OF THE PROJECT

2.1 Project Requirements

2.1.1 An EIA study is required to provide information on the nature and extent of environmental impacts arising from the construction and operation of the Project. Concurrent activities related to the Project also need to be included in the EIA study.

2.1.2 The EIA study addresses the following key environmental issues:

· Air quality impacts

· Noise impacts

· Water quality impacts

· Aquatic and terrestrial ecological impacts

· Fisheries impacts

· Landscape and visual impacts

· Cultural heritage impacts

· Cumulative environmental impacts

2.1.3 The other environmental issues including waste management, hazard to life and environmental monitoring and audit are also part of the EIA study.

2.1.4 In addition, the EIA study also considers and investigates:

· Other feasible alignment options for the Project;

· Alternative built form and design of the highway;

· The environmental benefits and dis-benefits of possible alignment options with recommendations on the preferred option, which is environmentally acceptable;

· Alternative construction methods to minimise impacts to the sensitive receivers; and

· Alternative sequences of works to avoid prolonged adverse environmental impacts.

2.2 Site Location and Study Area

Site History

2.2.1 Deep Bay was historically one of the major agricultural areas of the north-western New Territories. The coastal area comprises low-lying mudflats and brackish back swamps. Mangroves fringe the shoreline and the mudflats are a refuge for a wide variety of crustaceans and other fauna. Accretion of sediment around the roots of the mangroves had led to a seaward extension of the mudflats and consequently of the coastline. Inter-tidal channels occur along the eastern margin of the bay where the Shenzhen and Shan Pui rivers discharge fresh water into the bay.

2.2.2 Fishing and oyster gathering were major local activities since the mid-eighteenth centuries, undertaken mainly by boat-dwelling Tanka and Hoklo people and later with considerable Punti participation in the oyster industry. Land-dwellers were also involved in coastal fisheries, fish-ponds were a major source of revenue in the Deep Bay area until the late 1980s. Commercial oyster production has long been a mainstay of the Deep Bay economy with Lau Fau Shan as the centre of the industry.

2.2.3 Gei-wai or salt-paddy reclamation had been formed by local farmers in the area extensively back in the 1920s and 1930s. This has resulted the shoreline to move steadily northwards over the past century. Yuen Long's Tin Hau Temple, which dates in parts from the mid-eighteenth century, was once located on or very near the Deep Bay coastlines and is now over 2 kilometres inland.
Site Location and Study Area

2.2.4 The proposed SWC is located within Deep Bay, which is known to be an ecologically sensitive area. The Inner Deep Bay has most significant environmental value such as mudflats, mangroves and Gei Wai supporting a significant bird population.

2.2.5 The study area envelope for the proposed alignments covers a corridor in Deep Bay and a strip of land along north-western territory of the HKSAR. The two potential landing points on the Hong Kong side are Ngau Hom Shek and Ngau Hom Sha. The Deep Bay Road running along the coastline is the only existing land access to the landing points. Figure 1.1 (presented in Section 1) shows the site location and the SWC alignments.

2.2.6 Based on the study brief requirements, the study area for the key environmental issues is described in Table 2.1.
Table 2.1 Study Area

2.3 Project Nature, Scope and Benefits of the Project

Project Nature

2.3.1 The proposed SWC to be constructed in the Hong Kong portion is a dual-3 lane highway across Deep Bay to link up Shekou in the Mainland with the north-western territory of the HKSAR. The nature of the project is described below:

· The highway will be constructed tentatively on bridge structure. The section of the highway within the HKSAR waters, about 3.2km in length, will be constructed under this Project. Other structural forms of the highway will be reviewed and investigated.

· At the northern end, the proposed highway will be connected to the section of the road at the Shenzhen/HKSAR boundary to be constructed by the Mainland authorities (the Mainland Section). The landing location in Shenzhen will be located at Dongjiaotou.

· At the southern end, the proposed highway will be connected to the future Deep Bay Link (DBL) in the HKSAR.

· Two possible landing locations, on at Ngau Hom Shek and another at Ngau Hom Sha, had been investigated under the DBL project for connection by the SWC. Subsequently, landing point had been confirmed at Ngau Hom Shek.

· Whereas almost all the permanent works will be located offshore, certain activities will have to be carried out on land in the works area along the access roads.

Project Scope

2.3.2 The scope of this project includes:

· A dual-3 carriageway elevated structure, with hard shoulder, linking the proposed Deep Bay Link to the section of SWC within the boundary of the Mainland. The carriageway and elevated structure shall be designed and constructed to meet the standards and requirements on both the Mainland side and the Hong Kong side; and

· Associated civil, structural, marine, geotechnical, environmental protection, landscape and drainage works.
Benefits of the Project

2.3.3 The SWC may attract vehicles from the existing vehicular crossings including Sha Tau Kok, Lok Ma Chau and Man Kam To. The proposed highway would be the fourth boundary road crossing providing relief to the traffic congestion at the existing boundary crossings. After the completion of the SWC, vehicles can take the more direct route through the SWC rather than using the existing coastal roads to travel between Shekou and Hong Kong. A direct benefit of taking a more direct route through SWC is to reduce fuel consumption resulting in energy saving and reduction in air pollution in Hong Kong and Shekou.

2.3.4 The Project may also increase tourists and the economic activities between Hong Kong and Shenzhen and would enhance the social and economical co-operation for both sides.

2.4 Design of the Project

2.4.1 The SWC is a dual-3 lane carriageway with hard shoulders. The length of the highway section within the Hong Kong boundary is about 3.2 km and within the Mainland boundary is about 2 km. It links the proposed Deep Bay Link to the section of SWC within the Mainland boundary. There would be two potential landing points on the Hong Kong side including Ngau Hom Shek and Ngau Hom Sha. The HKSARG will be responsible for the construction of the highway section within the Hong Kong boundary whilst the Shenzhen authorities will be responsible for the construction of the highway section within the Mainland boundary. The landing point in Shenzhen will be at Dongjiaotou.

2.4.2 As specified in the study brief, alternative options and built forms need to be considered. This Project has investigated alternative tunnel and bridge alignment options. Evaluation and ranking of different options have been made with consideration on traffic, engineering, environmental, marine, land, implementation programme, public perception and cost issues.

2.4.3 Conceptual design for the selected structural options for the whole length of the SWC from the landing point on the Hong Kong side to the landing point at the reclaimed land on the Shenzhen side has been produced. The conceptual design allows flexibility for possible future design variation to avoid reassessing the environmental impacts at the detailed design stage.

2.4.4 The conceptual design covers the basic options for the typical spans that includes

· Option 1 split deck with inclined vertical face box girder, and vase shaped column;

· Option 1a split deck with double curved soffit box girder and elliptical columns;

· Option 2 split deck with single curved soffit box girder, and oval columns;

· Option 3 twin cell box girder, with Y-shaped column.

2.4.5 The conceptual design covers the basic options for the main spans at northern and southern channels that includes

· Option 1 Cable-Stayed Bridge with Inclined Tower;

· Option 2 Cable-Stayed Bridge with Kinked Tower;

· Option 3 Beam Bridge;

· Option 4 Twin Arch Bridge.

2.4.6 The conceptual design also covers the different types of substructures for the different bridge deck options.

2.4.7 The current bridge design option for the typical span is based on generally 75m span split deck with double reverse curve streamline soffit and elliptical column shape. The main span is a cable stayed bridge option with inclined tower spanning over the southern navigation channel. The general layout arrangement of the proposed bridge scheme are shown in Figures 2.1 to 2.5.

2.5 Land Requirements

2.5.1 The land requirement within the vicinity of SWC is shown in Figure 2.6. Several areas of private lots, short term tenancies, and government land allocations will be affected by the construction of the proposed works.

2.5.2 When SWC is in construction and operation, the oyster beds would be directly affected by the Project. The affected oyster bed tenancy area is shown in Figure 2.7 to 2.9.

2.5.3 A strip of area, connected to DBL works area near SWC/DBL interface, is planned to be demarcated as works area for contractor's accommodation and Resident Engineer office. Moreover, areas around the SWC/DBL interface will be demarcated as works area for construction of SWC. Locations and the extent are shown in Figure 2.6.

2.6 Construction Methods and Sequence of Works

2.6.1 For bridge span lengths between 60m and 100m there are a number of construction techniques traditionally adopted. These methods include launching of concrete box girders and in-situ or precast segmental box girders. Due to the span lengths for the SWC viaducts other options such as in-situ concrete slabs and precast concrete beams have not been considered. The following paragraphs describe the envisaged construction methods to be adopted.

2.6.2 The current access to the possible landfall sites in Hong Kong is via Deep Bay Road. This road is not suitable for transportation of construction materials or precast deck units, as the existing one-lane two ways traffic lane is insufficient in width.

2.6.3 Due to the private land ownership constraints in the landfall sites vicinity, there will be insufficient space for a precast yard at this location. In view of this limitation, it is anticipated that segments would be cast in the Mainland and brought to Hong Kong either to a barging point in or direct lifted to place. This arrangement is similar to other major viaduct contracts in Hong Kong.

2.6.4 One of the construction methods to construct viaducts over the mudflat area with limited water depth is using a temporary bridge platform. Figure 2.10 shows the envisaged construction phasing sequence of the works. The temporary bridge can be supported by small diameter pipe-pile with steel deck running alongside the SWC alignment. The temporary access bridge will be built in two sections, i.e. one section starting from the shoreline at Ngau Hom Shek towards the seaside, and the other section starting at deeper water level at about 1.85km from the shoreline and extending towards the landside. These two sections will meet over the mudflat area. This temporary platform can serve as a marine construction access by barge and can also serve as an easy and quick access from land side during construction. This temporary access platform bridging over the mudflat area can also minimise the environmental impact to the area during construction. A large temporary storage platform will be formed in the deeper water region using two barges secured in position at the end of the temporary bridge to provide a large storage area for construction materials and storage of the precast segment before lifted to place. A berthing area outside the southern navigation channel will be used for loading and unloading of the barges. Tee-off platform at each pier location provides an area for the bridge substructure construction.

2.6.5 Foundation for the SWC is proposed to be large diameter bored pile, which is very common for bridges over water. The piles are constructed from barges in the deeper water region or temporary tee-off platforms in the regions of shallow water. The piles would be founded on moderately decomposed rock of 5000 kPa allowable bearing pressure. In order to take full advantage of the higher stress of the pile shaft, as compared with the strength of the rock, the base of the pile can be enlarged or socketed into rock.

2.6.6 All pile caps will be buried in the seabed except for the cable-stayed bridge section, where the pile caps will be exposed just above the highest tidal level. Excavation will then be carried out within the de-watered sheet-piled cofferdam in order to expose the pile heads to be trimmed down to the cut off depth. The reinforcement cage will be fixed and concrete is poured. This will require temporary cofferdams of relatively good cut-off for dewatering. The sheet-piles will also need to be installed deep enough for stability.

2.6.7 Precast segmental balanced cantilever construction method is proposed for the approach viaducts construction. This is a common, fast and mature method adopted worldwide. It is carried out either using launching gantry from deck level or by crane from a barge. The use of launching gantry has benefits over lifting from a barge. Temporary supports are required only for the first segment to be placed at the pier with subsequent segments placed either side of this initial segment in a progressive manner. These segments are fixed by means of epoxy and temporary prestress until an in-situ stitch is formed at the centre span between the last two segments. See Figure 2.11.

2.6.8 Construction of the cable-stayed bridge will involve the installation and later retraction of temporary supports in the back spans to facilitate in-situ casting of both back spans before erection of the main span can commence. After completion of the back span, the inclined tower can start construction using 4m climbing form. After completion of certain height of the tower, the main spans and cables can be constructed and installed progressively with the tower construction. See Figure 2.12.

2.6.9 Construction of bridge foundations will generate excavated marine mud materials that will be required to be disposed off site. It is envisaged that these materials will be transported off the site by barge or truck via the temporary bridge. Cofferdam and closed grab dredger will be used during dredging operation to prevent spillage of sediment into the surrounding water.

2.6.10 Upon the completion of construction, the temporary bridge will be dismantled and the associate piles will be removed using a heavy-duty vibrator.

2.6.11 In order to meet the completion date by end of year 2005, a number of work fronts would be constructed concurrently. During the critical period, there will be about 7 pairs of pier sites foundation construction at the same time. The water quality impact assessment results have shown that the numbers pairs of pier sites foundation construction can be increased to 8 piers site at a time should this become necessary in the construction works programme.

2.6.12 A barging point at Lung Kwu Sheung Tan has been proposed for batching plant, precasting and storage.

Other Alternative Construction Methodology Considered

2.6.13 There are a few alternatives to the proposed use of temporary access bridge stated in papa. 2.6.4. These include constructing a temporary bund from the shoreline towards the seaside alongside the SWC alignment for transporting of construction materials and construction plant for piling and construction of the substructure over the mudflat area. Other possible methods involve the use of temporary access platform or temporary pontoon platform to be placed directly above the mudflat area for access of the construction vehicles over the mudflat area. These methods however will have direct impact to the mudflat area includes impact to the water flow and temporary loss of mudflat area for birds feeding ground during construction period. These methods are therefore not recommended.

2.6.14 The alternative construction methods to the superstructure are described as follows:

In-situ Balanced Cantilever Box Girders

2.6.15 This structural form is one that is considered suitable for the span lengths under consideration for the SWC viaducts. For larger spans this method is characterised by the requirement for a large haunch at the piers cast as a balanced cantilever from a travelling form. Whilst there are benefits associated with flexibility of spans lengths (not a significant benefit on SWC due to minimal amount of obstructions) the method may not suitable for a marine based environment due to the labour intensive work at the work site. In addition, the construction duration will be longer than for other construction methods. Figure 2.13 illustrates the general construction steps of this method.
Incrementally Launched Box Girders

2.6.16 Construction commences at one end of a bridge with segments pushed or pulled out over the supports. Segments length are much longer for this option compared to the balanced cantilever method. With a span of 75m this method will likely require a single temporary support for completion of each span. This will prove difficult in a marine environment. In addition, this method is limited for the alignment with perfectly straight or alternatively of constant radius of both horizontal and vertical of the deck, however that is not the case of the SWC alignment. Figure 2.14 illustrates the general construction steps of this method.

In-situ Span by Span Construction

2.6.17 The construction method comprises of adopting an underslung gantry which doubles as the deck formwork. This method can be used for construction for up to 80m spans although the major disadvantage is the labour intensive activities associated with the construction of significant information. The gantry/formwork will be supported on the piers with no temporary supports required. This will have obvious environmental benefits. Figure 2.15 illustrates the general construction steps of this method.

Other Alternative Construction Sequence Considered

2.6.18 The construction sequence described in papa. 2.6.4 and illustrated in Figure 2.7 allows the construction of SWC from various concurrent sites to meet the construction programme taking into account constraints to noise, water quality and ecology impacts. Other possible alternative construction sequences considered include placing temporary pontoon platform to create temporary access to build the substructure, the temporary platform can be placed from the shoreline and stretch into the middle of the bay or vice versa. Construction of substructure can start when the temporary platforms are in placed. However, as stated in papa. 2.6.13, this method will have direct impact to the water quality and the mudflat, it is therefore not recommended.

2.7 Operation of the Project

2.7.1 Operational activities, on completion of the Project, would comprise essentially traffic movements on the new SWC expressway from DBL to Shekou. There will be some changes of land uses along the SWC alignment. The operation of the whole SWC is currently under discussion between HKSARG and the Mainland Authorities.

2.8 Works Programme

2.8.1 The Project is planned to commence construction in August 2003 and is expected for completion by end of 2005. Figure 2.16 shows the works programme for the SWC project. The construction period for the Project is about two and a half years.

2.8.2 The works programme includes 3 months of mitigation works for rescue excavation of archaeological features within and also possibly west of the Ngau Hom Shek Archaeological Beach Site area.

2.8.3 After consideration of the time required for each construction activity and phasing of the works, the critical period of multi-front construction in Deep Bay would occur in between June 2004 and September 2004. There would be in total 7 pairs of pier sites under construction at the same time; this includes 2 pairs of piers within 600m intertidal area from the shoreline, 3 pairs of piers in the shallow water area beyond the 600m from shoreline and 2 pairs of piers in the deeper water area towards the middle of the bay (see Figure 2.10).

2.9 Scenario With or Without the Project

2.9.1 There is an increasing demand on cross-boundary traffic between the HKSAR and the Mainland. The proposed Shenzhen Western Corridor would be the forth boundary road crossing. With the implementation of the Project, there would be an alternative route to travel between Hong Kong and Shenzhen. The Project provides relief to the traffic congestion at the existing boundary crossings and to establish HKSAR as a logistic centre of the Pearl River Delta.

2.9.2 The Project may provide opportunities to increase tourists and to strengthen the social and economical co-operation for both sides. The increases in economic activities would have an advantage to widen the economic base of Hong Kong and may create new job opportunities.

2.9.3 Without the Project, the rapid traffic growth in the region may not be easily resolved and may cause traffic congestion for vehicles travelling between Hong Kong and Shenzhen. This may also slow down the socio-economic linkages between the HKSAR and the Mainland. Further developments of the Hong Kong economical activities may be limited.

2.9.4 The scenario with the Project would involve extensive construction activities that may cause environmental impacts to the existing environment in Deep Bay. The operation of the SWC may also cause impacts to the environment to a certain extent. The key environmental issues may cover air quality, noise, water quality, waste, ecology and fisheries, cultural heritage, and landscape and visual. The construction phase impacts are temporary and the operational phase impacts are permanent. If the potential environmental impacts can be minimised through implementation of suitable mitigation measures leading to minimal residual impacts, the scenario with the Project would still be environmentally acceptable. Unmitigated scenarios are likely to cause unacceptable environmental impacts. The environmental conditions for the scenario without the Project would remain natural.

2.10 Concurrent Projects

2.10.1 The concurrent projects which have been planned or are in the vicinity of the SWC include:

· Water Supply to Hung Shui Kiu, Kwu Tung North, Fanling North and Ping Che/Ta Kwu Ling New Development Areas

· Water Supply to Sludge Treatment Facility at Tuen Mun

· Yuen Long and Kam Tin Sewerage and Sewage Disposal" PWP Item No. 4215DS

· Upgrading & Expansion of San Wai Sewage Treatment Works and the Expansion of Ha Tsuen Pumping Station

· Hung Shui Kiu New Development Area (HSK NDA)

· Deep Bay Link (DBL)

· The Mainland Section of SWC.

Water Supply to Hung Shui Kiu, Kwu Tung North, Fanling North and Ping Che/Ta Kwu Ling New Development Areas

2.10.2 WSD planned to supply salt water to the proposed New Development Areas (NDAs) in Northern New Territories, including Hung Shui Kiu NDA, Kwu Tung North NDA, Fanling North NDA, Ping Che/Ta Kwu Ling NDA etc. The proposed salt water inlet is located at Lung Kwu Sheung Tan where a seawater pumping station is situated. A 900mm diameter salt water main is proposed to be laid along the Deep Bay Road, passing through Fung Kong Tsuen Road to Hung Shui Kiu NDA and other areas.

2.10.3 The section of pipe proposed to be laid along the Deep Bay Road and the Fung Kong Tsuen Road leading to the existing WSD's water tank will fall within the proposed SWC site boundary. Being buried pipelines, no conflict with SWC is anticipated since the piers of SWC viaduct can be designed to locate away from them. The exact location of the piers will be worked out in detailed design stage and discussed with WSD.

2.10.4 In addition to the salt water main, a salt water service reservoir is also proposed under this WSD project. The tentative location would be near the Fung Kong Tsuen Road at hillside of Fung Kong Tsuen. Since the proposed reservoir is located outside the works limit of SWC, it will not conflict directly with the SWC construction.

2.10.5 The tentative construction programme of this WSD project is scheduled to commence in around late 2005 and early 2006 for completion by 2009 that may overlap with the construction period of SWC in 2005. However, the SWC construction is nearly completed in 2005 and the construction traffic will be very low. Moreover, the construction traffic of the WSD project is anticipated low during the early stage of construction. Thus programming and construction traffic conflict between the two projects is minimal.

2.10.6 As this salt water supply scheme is still in preliminary feasibility study stage, it may have changes during the course of design development. Liaison closely with WSD is required in the detailed design stage of SWC.

Water Supply to Sludge Treatment Facility at Tuen Mun

2.10.7 Fresh water main of 450mm-diameter is proposed by WSD to be laid along the Deep Bay Road, connecting with the proposed sludge treatment facility near WENT landfill site, passing through Nim Wan Road, Lau Fau Shan Road, Tin Wah Road and Tin Ying Road, to an existing 600mm-diameter fresh water main in Tin Shui Wai.

2.10.8 As the SWC viaduct will be constructed over the Deep Bay Road and the piers will be designed to locate well away from the road in order to maintain the normal traffic along Deep Bay Road during construction stage of SWC, hence no impact on the proposed fresh water main is expected.

2.10.9 The fresh water main is scheduled to be constructed in 2005 for completion in 2008 that will overlap with SWC construction in 2005 but that is not the peak year of SWC construction and also the Deep Bay Road is not proposed as the haul road for SWC, thus programming and construction traffic conflict would not be significant.

2.10.10 As the alignment of the proposed fresh water main is tentative currently, it will be changed subject to further investigation. Close liaison with WSD is needed.

Yuen Long and Kam Tin Sewerage and Sewage Disposal" PWP Item No. 4215DS

2.10.11 To the northeast of SWC near Tin Shui Wai, DSD is planning a sewage disposal project - "Yuen Long and Kam Tin Sewerage and Sewage Disposal" PWP Item No. 4215DS. Rising mains and gravity sewers are proposed to be placed at Tin Ying Road, Tin Wah Road and Lau Fau Shan Road.

2.10.12 Although the proposed works are not physically clashed with SWC, the construction of this project is tentatively scheduled to commence in May 2005 for completion in August 2007 that will overlap with SWC construction in 2005 but that is not the peak year of SWC construction, thus programming conflict would not be significant. Further liaison with DSD is necessary during the detailed design stage.

Upgrading & Expansion of San Wai Sewage Treatment Works and the Expansion of Ha Tsuen Pumping Station

2.10.13 For this Drainage Services Department (DSD)-managed project, the construction work would commence in around 2004. The only part of construction routes common to both projects may include Tin Ying road, Hung Tin Road and the flyover above the junction of 'Tin Ying Road/Hung Tin Road/Ping Ha Road'. It is assumed that the maximum two-way construction traffic would be approximately 10 pcu per hour. The cumulative construction traffic impact would be minimal to the two projects concerned.

Hung Shui Kiu New Development Area (HSK NDA)

2.10.14 HSK NDA is a major development proposed near DBL. It is encompassed by DBL, CPR, Hung Tin Road and some local roads in TSW area. According to "Planning and Development Study on NWNT, Technical Paper No.12 (TP12A) (Final), Traffic Impact Assessment (September 2001)", the initial population intake would be in 2008. As indicated in the technical paper, HSK NDA construction works would start in 2004, with the final contract due to complete in 2008. The development programme is subject to review upon the confirmation of the implementation mechanisms.

2.10.15 During the critical construction traffic period of SWC in 2004, the early stages of HSK NDA construction work would also take place. According to the information presented in the technical paper, construction traffics of each contract of HSK NDA access various works areas will be via haul roads Hung Tin Road, Ping Ha Road, Tin Ha Road and Yick Yuen Road from CPR, whereas construction traffic routes for SWC are Fung Kong Tsuen Road, Tin Wah Road, Tin Ying Road and YLH. In addition, the site limit of SWC is far away from the HSK NDA. Thus, both projects will not conflict each other.

2.10.16 Apart from above, a fresh water service reservoir is also proposed in HSK NDA project for water supply to HSK New Town. The location is proposed at Fung Kong Tsuen near Fung Kong Tsuen Road adjacent to the WSD proposed alternative site (A-SR3) for salt water service reservoir. As advised by TDD that construction of the reservoir will commence in around late 2005 and early 2006 for completion by 2008. Considering that SWC will be nearly completed by end 2005, construction works of the reservoir will not impose significant impact on the SWC construction traffic via Fung Kong Tsuen Road.

Deep Bay Link (DBL)

2.10.17 The Deep Bay Link is a dual 3-lane trunk road, it starts at the shoreline of Deep Bay at Ngau Hom Shek ands at Yuen Long Highway (YLH) Lam Tei at the southern end. It connects the proposed SWC to both Yuen Long Highway and the proposed Route 10. The total length of the mainline is 5.4km to the Lam Tei Tunnel Toll Plaza, however in order to provide working space for the SWC, a section of 300m long viaduct on land is entrusted to the SWC design package. Hence the actual starting point of the DBL D&C Assignment at the northern end is 300m south of the shoreline. At the southern end, due to the delay of the Route 10, all proposed DBL and YLH roads connecting Route 10 will not be constructed at this phase and the DBL mainline will stop at around 750m north of the Lam Tei Tunnel toll-plaza. As a result of the shrinkage at both ends, the mainline is now reduced to around 4.35km long.

2.10.18 There are 5 ramps of some 2km long forming the Lam Tei Interchange to connect the DBL and YLH in the east and west direction. There are 4 ramps at the Ha Tsuen Interchange, which will form the turn around facility and future connection to the road system of the Hung Shui Kiu New Development Area (HSK NDA). Stub ends are provided at the Hung Shui Kiu Interchange to receive ramps connecting to HSK NDA. Apart from Ramp K, all the ramps for the HSK Interchange will be constructed by others at a later stage.

2.10.19 Two kilometres of YLH widening from dual 2-lane to dual 3-lane is also included in the scope. The western end of this section of YLH is at the existing Lam Tei Interchange Fu Tei and the Eastern end is Tan Kwai Tsuen. The rest of the YLH will be widened to dual 3-lane by others with a similar construction programme.

2.10.20 It is understood that although the portion of DBL mainline is not constructed to meet the LTT toll plaza at this stage, piers within YLH will be constructed at this stage such that only the bridge deck will be constructed in future avoiding complicated TTM during construction of the substructures.

2.10.21 The majority of the design and construction works are the viaducts and the ramps, 80% of the mainline being on viaduct. A span will span over Castle Peak Road and LRT and a span will span over KCRC West Rail and its EVA 26. There are associated drainage, utilities, earthworks, environmental mitigation measures, landscape, weighting station, residual BCF, helipad and all sort of re-provision works for the completion of the project.

2.10.22 DBL will be constructed concurrently with SWC and is expected to be in operation by end of 2005.

The Mainland Section of SWC

2.10.23 Shenzhen Western Corridor from the HKSAR water is connected to the west by about 2km long of the Mainland portion of SWC (or kwon as the Shenzhen-Hongkong Western Corridor). The SWC in the Mainland waters is the continuation of the proposed S curve connecting to the HKSAR SWC portion. A cable-stayed bridge section is proposed over the northern navigation channel.

2.10.24 The landing point on the Mainland side is on Dongjiaotou, a reclaimed land of about 150ha in area. The seawall construction for the landing point started in March 2002 and is expected to complete in October 2002. Water will then be pumped out inside the enclosed seawall and reclamation will be filled behind the seawall. The reclamation work for the SWC bridge landing point portion is expected to be completed in June 2003, whilst the whole reclamation area is expected to be completed in June 2004.

2.10.25 The landing point in Dongjiaotou will also house the co-located boundary crossing facilities for both HKSARG and Mainland Authorities and the associated infrastructures. The SWC will then connect to the Shenzhen local road network from Dongjiaotou.