Table of Contents

2.           Project DESCRIPTION.. 2-1

2.1         Introduction. 2-1

2.2         Existing Road Networks. 2-1

2.3         The Need for the Project 2-1

2.4         Benefit of the Project 2-1

2.5         Proposed Road Works. 2-2

2.6         Consideration of Alternative Options. 2-2

2.7         Screening of the Options. 2-5

2.8         Evaluation of Options. 2-5

2.9         Construction Method and Engineering Requirements. 2-19

2.10       Works Programme. 2-21

2.11       Concurrent Project 2-21

 

 

LIST OF TABLES

 

Table 2-1         Consideration on Permanent Traffic Arrangement 2-6

Table 2-2         Consideration on Alignment Design Standard. 2-6

Table 2-3         Consideration on Traffic Impact at Construction Stage. 2-8

Table 2-4         Consideration on Other Operational Factors. 2-9

Table 2-5         Consideration on Bridge Scheme. 2-9

Table 2-6         Consideration on Noise Mitigation Measure. 2-10

Table 2-7         Consideration on Bridge Scheme. 2-12

Table 2-8         Consideration on Other Elements. 2-12

Table 2-9         Consideration on Land Requirement 2-13

Table 2-10a     Consideration on Environmental Impact 2-14

Table 2-10b     Rankings of Factors of Environmental Impacts

Table 2-11       Consideration on Capital and Recurrent Cost 2-15

Table 2-12       Consideration on Maintenance Consideration. 2-16

Table 2-13       Consideration on Time for Completion. 2-17

Table 2-14       Overall Marking and Overall Ranking for Identified Options. 2-18

Table 2-15       Major Concurrent Projects. 2-21

 

 

LIST OF FIGURES

 

Figure 2.1            Proposed Road Works

Figure 2.2            Sections of Proposed Road Works

Figure 2.3            Option 1: Separate Viaduct on East Side of TWR (design speed 50 km/h)

Figure 2.4            Option 1A: Separate Viaduct on East Side of TWR (design speed 70 km/h)

Figure 2.5            Option 2: Separate Viaduct on West Side of TWR (design speed 50 km/h)

Figure 2.6            Option 2A: Separate Viaduct on West Side of TWR (design speed 70 km/h)

Figure 2.7            Option 2B: Separate Viaduct on West Side of TWR and merging nearside lane of TWR with KCR Upramp (design speed 70 km/h)

Figure 2.8            Option 3: Widening along both Nearside and Offside Lanes of TWR (design speed 70 km/h)

Figure 2.9            Option 3A: Widening along both Nearside and Offside Lanes of TWR and Merging Nearside Lane of TWR with KCR Upramp (design speed 70 km/h)

 

 

APPENDICES

 

Appendix 2-1      Tentative Construction Programme

 

 

 

 

 


2.                       Project DESCRIPTION

2.1                   Introduction

2.1.1             This section presents a summary of the adopted alignment and preferred construction methodology for the Project as well as provides details of the alternative options considered, the constraints and considerations assessed in adopting the preferred scheme and construction method.

2.2                   Existing Road Networks

2.2.1             Major roads inside the study area of the Project include Kwai Tsing Interchange (KT I/C) Upramp, Tsuen Wan Road (TWR), Kwai Chung Road (KCR) and Kwai Chung Road Upramp as well as Tsing Kwai Highway (TK H/W) and Tsing Kwai Highway Upramp. 

2.2.2             KCR upramp runs parallel with KCR where it intersects with TWR and connects with KCR at grade.  The primary purpose of this upramp is to allow traffic from KCR to access Tsing Kwai Highway (Route 3).  Therefore, regulatory marking which prohibits traffic weaving from the nearside lane of KCR southbound (SB) outside Lai King Estate is in place.

2.2.3             TWR is generally a dual-three expressway providing connections between KCR / TK H/W and TMR.

2.2.4             Tsing Kwai Highway ramp has two traffic lanes linking KCR and TK H/W.

2.3                   The Need for the Project

2.3.1             As mentioned in Section 1, Transport Department (TD) has reviewed the traffic conditions of TWR near KT I/C and considered that a section of the southbound carriageway of TWR between KT I/C and KCR would deteriorate due to congestion occurs during peak hours in the future years. TD considers that there is a need to implement the Project to improve the road section to cope with future traffic growth.

2.3.2             According to the Traffic Impact Assessment (TIA) carried out under this Project, the section of the southbound carriageway of TWR between KT I/C and KCR is currently operating marginally above capacity in the morning peak hours and it is envisaged that the congestion would continue to worsen in the future years. The TIA has confirmed that with the introduction of an additional traffic lane (i.e. the Project), this section of the southbound carriageway of TWR would be operating within capacity in both the morning and evening peak hours in all design years.

2.3.3             The TIA has also confirmed that the Project would not cause adverse impact on the local road junctions.

2.4                   Benefit of the Project

2.4.1             A section of the SB carriageway of TWR between KT I/C and KCR has been predicted to be deteriorated due to congestion occurs during peak hours in the future years. An additional one-lan flyover is therefore proposed to improve the road section to cope with the future traffic growth by directing traffic flow from fast lane of SB TWR to merge the fast lane of SB KCR.  This would decrease the ratio of the traffic volume to the road link capacity (v/c ratio) on the concerned section, i.e. reduce chance of traffic congestion in future.

2.4.2             Since the proposed new flyover shall be connecting with the fast lane of SB TWR, it would therefore direct some of the on-road traffic away from the nearby noise sensitive receivers at Lai King Estate.  In addition, it is feasible to cope with direct noise mitigation measures as needed associated with the new flyover construction.  In this connection, traffic noise impact due to TWR could be slightly relieved with this Project in place. 

2.4.3             With the decrease of v/c ratio on SB TWR when this Project is in place, local traffic congestion problem could be resolved.  In other words, the on road traffic speed would be resumed to the design speed limit instead of idling during rush hours.  As a result, the overall vehicular emission would likely be reduced in the vicinity area in the future.   

2.4.4             In summary, the Project would not only improve traffic congestion problem but also introduce environmental benefits to the vicinity’s sensitive receivers in the future.

2.5                   Proposed Road Works

2.5.1             To fulfil the future demand and to prevent traffic congestion in the future during peak traffic flow hours, an additional southbound lane (a separated viaduct) is introduced on TWR and connected to the existing lane on the west side of KCR with design speed of 70 km/hr. 

2.5.2             The proposed road works and section drawings are shown in Figures 2.1 and 2.2 respectively, details would be presented in Section 2.6.  The basis of design for this proposed flyover is to utilise the remaining capacity currently available on the two segregated KCR carriageways. 

2.5.3             In addition, a second structure (approximately 150m long) along the nearside lane of TWR near existing KT I/C upramp is required to achieve widening at the east side of TWR.

2.5.4             Associated works in the following areas have been identified:

·      Existing footbridge NF303 is to be demolished and be re-provided;

·      Existing Public Works Regional Laboratory will be affected;

·      Existing drainage reserve zone positioned alongside TWR will be affected;

·      Existing bus stop outside subway NS10A is to be relocated; and

·      Minor modification to the existing KCR involves removal of the existing planter, breaking and reinstating KCR with the new road marking.

2.6                   Consideration of Alternative Options

Considered Options

2.6.1             The proposed flyover connects the KT I/C Upramp to KCR. Two improvement options, namely Option 1 and Option 2, were identified in Clause 3.1 of the Brief.  Two additional improvement options, Option 1A and Option 2A, have been developed by improving the road geometry of Option 1 and Option 2 respectively in order to achieve a design speed of 70km/hr, and to match the speed limit on the existing TWR.  Another improvement option, Option 3, which is based on widening along both nearside and offside lanes of TWR, has also been identified in the “Working Paper on Alignment Options and Assumptions” under this Project.

2.6.2             Subsequent to the circulation of the aforementioned working paper, which covers Options 1, 1A, 2, 2A and 3, two additional options, namely Option 2B and Option 3A have been developed in the report named “Report on the Development and Evaluation of Options”.  Option 2B is similar to Option 2 and 2A; and Option 3A is similar to Option 3.

2.6.3             Figures for these seven options are depicted in Figures 2.3 to 2.9 while a summary of these considered options are as follows:

·      Option 1:      Separate Viaduct on East Side of TWR (Design Speed 50km/hr)

·      Option 1A:   Separate Viaduct on East Side of TWR (Design Speed 70km/hr)

·      Option 2:      Separate Viaduct on West Side of TWR (Design Speed 50km/hr)

·      Option 2A:   Separate Viaduct on West Side of TWR (Design Speed 70km/hr)

·      Option 2B:   Separate Viaduct on West Side of TWR and Merging Nearside Lane of TWR with KCR Upramp (Design Speed 70km/hr)

·      Option 3:      Widening Along Both Nearside and Offside Lanes of TWR (Design Speed 70km/hr)

·      Option 3A:   Widening Along Both Nearside and Offside Lanes of TWR and Merging Nearside Lane of TWR with KCR Upramp (Design Speed 70km/hr)

2.6.4             Option 1: Separate Viaduct on East Side of TWR (Design Speed 50km/hr)

This option introduces an additional southbound lane from KT I/C upramp which connects to the existing downslope segment of KCR upramp.  Currently, KCR upramp has a single traffic lane and is dedicated to Route 3 traffic, connecting KT I/C upamp to KCR upramp lane will require allowing non-Route 3 traffic leaving KCR upramp lane.  This is currently not allowed. This option is illustrated in Figure 2.3.  Results from the traffic survey undertaken have indicated that the KCR upramp lane has v/c ratios of 0.26 and 0.27 for am peak and pm peak respectively. The basis of the design for this option is to utilize the remaining capacity available on the KCR upramp lane.

The space available at the gap between piers D8 and D9 of Tsing Kwai Highway (TK H/W) elevated road is a constraint to the width of KT I/C upramp structure. A viaduct structure with design speed of 50km/hr can readily meet the horizontal clearance requirement. The design speed of 50km/hr is in compliance with Transport Planning and Design Manual (TPDM) requirement for slip roads, however, the speed limit on KCR upramp will need to be reduced to 50km/hr (from the current 70km/hr) to match KT I/C upramp, up to the straight section of KCR upramp where it runs parallel to the three lanes of TWR.  In addition, weaving movement (over approximately a 300m length) will have to be allowed to enable destination selection. 

2.6.5             Option 1A: Separate Viaduct on East Side of TWR (Design Speed 70km/hr)

This option is similar to Option 1 except the design speed of 70km/hr is adopted and consequently a wider road width on the curved section of the viaduct is required to achieve the required sight distance.  Widening of TWR on the west side is also required. This option is illustrated in Figure 2.4.

As compared with Option 1, a longer taper is required at the merge with KCR upramp, consequently only about 215m length (compared to 300m in Option 1) is available for weaving movement before the junction with Route 3 upramp.

2.6.6             Option 2: Separate Viaduct on West Side of TWR (Design Speed 50km/hr)

This option introduces an additional southbound lane on the west side of TWR and this lane is connected to the existing lane on the west side of KCR.  This option is illustrated in Figure 2.5.  Results from the traffic survey undertaken have indicated that the two segregated lanes on the west side of KCR have v/c ratio of 0.32 and 0.40 for am peak and pm peak respectively.  The basis of design for this option is to utilize the remaining capacity currently available on the two segregated. 

A separate viaduct structure with design speed of 50 km/hr on the west side of TWR is proposed. The space available at the gap between piers D6 and D7 of TK H/W elevated road is a constraint to the width of the viaduct structure.  The design speed of 50km/hr for the additional lane meets TPDM slip road standard.  This design speed will have to be maintained at 50km/hr up to the position where the lane merges with the adjacent lanes of KCR.  A second structure (150 m in length) along the nearside lane of TWR near existing KT I/C upramp is required to achieve widening at the east side of TWR. 

2.6.7             Option 2A: Separate Viaduct on West Side of TWR (Design Speed 70km/hr)

This is the preferred option for this Project.  This option is similar to Option 2 except the design speed is 70km/hr and a wider road width is provided due to the need for longer sight distance.  An additional southbound lane is introduced on TWR and this lane is carried through to KCR.  The two segregated lanes on the west side of KCR are to be merged into one to enable this arrangement. This option is illustrated in Figure 2.6.

Similar to Option 2, a second structure (150 m in length) along the nearside lane of TWR near existing KT I/C upramp is required to achieve widening at the east side of TWR. 

2.6.8             Option 2B: Separate Viaduct Option on West Side of TWR and Merging Nearside Lane of TWR with KCR Upramp (Design Speed 70km/hr)

The main difference of this option from Option 2A is that the segregated lanes on the west side of KCR will not be affected, and that the TWR nearside lane from KT I/C upramp is connected to the existing downslope segment of KCR upramp.  This option is illustrated in Figure 2.7.  The basis of design for this option is to utilize the remaining capacity available on the KT I/C upramp lane.  Results from the traffic survey undertaken have indicated that the KCR upramp lane have v/c ratio of 0.26 and 0.27 for am peak and pm peak respectively.

Similar to Option 2, a second structure (approximately 150 m in length) along the nearside lane of TWR near existing KT I/C upramp is required to achieve widening at the east side of TWR. 

2.6.9             Option 3: Widening along Both Nearside and Offside Lanes of TWR (Design Speed 70km/hr)

This option introduces an additional southbound lane on TWR and this lane is carried through to KCR.  The two segregated lanes on the west side of KCR are to be merged into one so that one traffic lane is available for connection to the additional southbound lane on TWR.  This option is illustrated in Figure 2.8.  The basis of design for this option is to utilize the remaining capacity available on the two segregated lanes on KCR.  Results from the traffic survey undertaken have indicated that the two segregated lanes on KCR have v/c ratio of 0.32 and 0.40 for am peak and pm peak respectively, i.e. there is spare capacity of over one traffic lane.

Widening structures are proposed along both edges of the existing TWR.  Designed for design speed of 70km/hr, which matches current TWR, the widening structures meet the horizontal clearance requirement between piers D7 and D8 of TK H/W elevated road.

2.6.10         Option 3A: Widening along Both Nearside and Offside Lanes of TWR and Merging Nearside Lane of TWR with KCR Upramp (Design Speed 70km/hr)

The main difference of this option from Option 3 is that the segregated lanes on the west side of KCR will not be affected, and that the TWR nearside lane from KT I/C upramp is connected to the existing downslope segment of KCR upramp.  This option is illustrated in Figure 2.9.  The basis of design for this option is to utilize the remaining capacity available on the KCR upramp lane.  Results from the traffic survey have indicated that the KCR upramp lane have v/c ratio of 0.26 and 0.27 for am peak and pm peak respectively.

Widening structures are proposed along both edges of the existing TWR.  Designed for design speed of 70km/hr, which matches current TWR, the widening structures meet the horizontal clearance requirement between piers D7 and D8 of TK H/W elevated road.

2.7                   Screening of the Options

2.7.1             Referring to the “Report on the Development and Evaluation of Options” report, three criteria have been conducted to screen out infeasible options:

·      For option that introduces weaving, weaving analysis based on preliminary traffic forecast;

·      Compliance with TPDM standards; and

·      Feasibility assessment on the proposed bridge scheme.

2.7.2             Out of the seven options presented above, Options namely Option 1 and Option 1A were screened out due to non-compliance with the weaving requirements in that the number of lanes required could not be achieved along the weaving section between KCR upramp and KCR southbound. Another option namely Option 2B was eliminated under the screening assessment as well due to the insufficient deck depth of Bridge P available. This structural depth is constrained by the vertical profile of the road alignment and the minimum 5.1m headroom of KCR below. 

2.8                   Evaluation of Options

2.8.1             There are 13 viewpoints in evaluation of the remaining options:

Traffic & Other Operational Consideration

(I)           Permanent Traffic Arrangement

The road improvement scheme is to provide an additional traffic lane for the southbound traffic between KT I/C upramp and KCR.  The critical factors that would affect permanent traffic arrangement are:

(i)            With the number of traffic lanes on KCR fixed, the reserve capacity of the existing lane will be critical to the performance of the improvement scheme.

(ii)          Change to current traffic arrangement.

The factors taken into consideration in comparison of the options are described in the table below with the ranking determined accordingly:


Table 2-1      Consideration on Permanent Traffic Arrangement

Option

Factors

*Ranking

2

 

(i)             This option requires the segregated lanes on KCR be merged prior to the introduction of the additional lane from the Project.  From the conducted traffic survey, the respective v/c ratio for the two segregated lanes on KCR was 0.32 and 0.40 for the am and pm peak respectively.  Capacity of more than one traffic lane is anticipated to be available.

(ii)           Merging the original two segregated lanes on KCR to one lane.  Based on v/c ratio, impact to traffic should be minimal.

1

2A

 

(i)            Identical to Option 2.

(ii)          Identical to Option 2.

1

3

 

(i)            Identical to Option 2.

(ii)          Identical to Option 2.

1

3A

 

(i)           This option converts the existing downslope segment of KCR Upramp lane as continuation of the additional lane and uses up its remaining capacity.  From the conducted traffic survey, the respective v/c ratio was 0.26 and 0.27 for the am and pm peak respectively.  Capacity of less than one traffic lane is therefore anticipated to be available.

(ii)         (a) A merge is introduced from the KCR upramp to TWR sacrificing the original priority of traffic destined for Route 3.

(b) In this option, early lane selection for TWR traffic is required for traffic destined for Route 3.

2

* Ranking: 1 = most preferable & 2 = least preferable under this viewpoint

(II)        Alignment Design Standard

According to TPDM, TWR and KCR are urban trunk roads which should have design speed of 80km/hr.  Due to the site constraints, design speed is to match with the existing speed limit (70km/hr) on TWR and KCR.  Comparisons among the options are therefore made to the corresponding alignment design standard and summarised in below table.

Table 2-2        Consideration on Alignment Design Standard

Alignment Design Standard

Option 2

Option 2A

Option 3

Option 3A

(i)

Design Speed

70km/h for existing TWR/KCR

50 km/h

70 km/h

70 km/h

70 km/h

(ii)

Lane Width

3.65m (minimum)

4.0m

4.0m

4.0m

4.0m

(iii)

Horizontal Curve

TPDM Vol. 2 Cl. 3.3.3.1

175m(R3) Desirable – 70km/hr

88m (R1) Absolute – 70km/hr

219.6m> R3

219.5m> R3

168.5m> R1

175m=R3

(iv)

Superelevation

TPDM Vol. 2 Cl. 3.3.3.3

7% for curve of radius < R4

10% for R3 radii or less

7%

10%

10%

10%

(v)

Sight Distance

TPDM Vol. 2 Cl. 3.3.5

120m Desirable

90m Absolute

50m

90m

90m

90m

(vi)

Vertical Gradient

TPDM Vol. 2 Cl. 3.3.6

4% Desirable

8% Absolute

10%

8%

6%

6%

(vii)

Vertical Curve (Crest) minimum K value

TPDM Vol. 2 Cl. 3.3.7

K=30 Desirable (70m/hr)

K=17 Absolute (70m/hr)

K=6.5

K=17.0

Match existing TWR

Match existing TWR

(viii)

Vertical Curve (Sag) minimum K value

TPDM Vol. 2 Cl. 3.3.7

K=20 Desirable (70m/hr)

K=20 Absolute (70m/hr)

K=13.0

K=20.0

Match existing TWR

Match existing TWR

(ix)

Merging Length

TPDM Vol. 2 Cl. 4.8.6.12

60m nose + 150m taper

{Not applicable}

{Not applicable}

{Not applicable}

60m nose + 150m taper

 

 

*Ranking

3

1

2

1

Note: Items complying with the design standard are underlined.  * Ranking: 1 = most preferable & 3 = least preferable under this viewpoint.

(III)          Traffic Impact at Construction Stage

In the construction stage, there would be impact, arising from both the construction activities as well as the additional construction traffic, to road traffic in the Project area.  Detailed evaluation and assessment with recommendation on the appropriate temporary traffic management scheme or other mitigation measures would be included under the construction traffic impact assessment in the TIA Report.  Comparison of different impacts arising from construction of major items of Works in the options have been conducted

Traffic through the existing road system in TWR should basically be maintained during the construction stage.  Impacts to the following major roads in the Project area are considered in turn:

(i)            Tsuen Wan Road

(ii)          Kwai Chung Road

(iii)        Kwai Chung Road Upramp

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly.


Table 2-3      Consideration on Traffic Impact at Construction Stage

Option

Factors

*Ranking

2

(i)         Considerable impact to traffic on TWR is anticipated due to the very long stitched joint between Grid E1 & E6.  Minor impact for the very localized stitched joint between Grid F1 & F3.

(ii)       There would be some impact during construction of the Grid F8 abutment.  Considerable impact to traffic on KCR for realignment of this road.  Some impact is anticipated for demolition of footbridge NF303 and for reconstruction.

(iii)     No impact.

1

2A

(i)         Considerable impact to traffic on TWR is anticipated due to the very long stitched joint between Grid G1 & G6.  Minor impact for the very localized stitched joint between Grid H1 & H3. 

(ii)       There would be some impact during construction of Grid H7 foundation and Grid H8 abutment.  Considerable impact to traffic on KCR for realignment of this road.  Some impact is anticipated for demolition of footbridge NF303 and for its reconstruction.

(iii)     No impact.

2

3

(i)         Considerable impact to traffic on TWR is anticipated due to the very long stitched joint between Grid J1 & J8.  Considerable impact is also anticipated for the very long stitched joint between Grid K1 & K6.  High impact during construction of NMM.

(ii)       There would be some impact during construction of Grid K5 foundation and Grid K6 abutment.  Considerable impact to traffic on KCR for realignment of this road.  Some impact is anticipated for demolition of footbridge NF303 and for its reconstruction.

(iii)     High impact during construction of NMM.

3

3A

(i)         Considerable impact to traffic on TWR is anticipated due to the very long stitched joint between Grid L1 & L8.  Considerable impact is also anticipated for the very long stitched joint between Grid M1 & M6.  High impact during construction of NMM.

(ii)       There would be some impact during construction of Grid M5 foundation and Grid M6 abutment.  Considerable impact to traffic on KCR for realignment of this road.  Some impact is anticipated for demolition of footbridge NF303 and for its reconstruction.

(iii)     High impact during construction of NMM.

3

* Ranking: 1 = most preferable & 3 = least preferable under this viewpoint

(IV)     Other Operational Consideration

Within the Project area, there is a bus stop originally located in front of a pedestrian subway (NS10A) which is now mainly serving the residents of Lai King Estate. It would be affected during construction and after the proposed flyover will be built.  Requirement of relocation is the critical issue on operational consideration.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly.

Table 2-4      Consideration on Other Operational Factors

Option

Factor (I)

*Ranking

2

Require relocation.

2

2A

Require relocation.

2

3

Require relocation.

2

3A

No relocation required.

1

* Ranking: 1 = most preferable & 2= least preferable under this viewpoint

Engineering Consideration

(V)        Bridge Scheme

The comparison is concentrated on the design of the bridge schemes.  The critical factors to be considered are:

(i)            The design should minimize the impact on existing and, in particular, lowering the risk and uncertainties associated with any required strengthening of the structure.

(ii)          The design should minimize the impact on Tsing Kwai Highway (TK H/W) elevated road and, in particular, lowering the risk and uncertainties associated with any required reconstruction of its bridge pier(s).

(iii)        The design should maintain adequate horizontal and vertical clearance to existing structures.

         The factors taken into consideration in comparison of the options are described in the following table with the ranking determined accordingly.

Table 2-5      Consideration on Bridge Scheme

Option

Factors

*Ranking

2

 

(i)          Bridge E is stitch joined (whole length) to existing TWR flyover by the nearside lane.  There could be need to strengthen existing TWR flyover.  Bridge F is a separate bridge structure.  A short stub end between Grid F1 & F2 is stitched to existing TWR flyover, but impact on it is very low.

(ii)        No reconstruction required on TK H/W piers.

(iii)      Bridge E: 5.11m vertical clearance to MTRC viaduct.  Bridge F: 6.06m & 0.66m horizontal clearance to TK H/W pier D6 and D7 respectively.  6.60m vertical clearance to TK H/W viaduct.

1

2A

 

(i)          Bridge G is stitch joined (whole length) to the existing upramp by the nearside lane.  There could be need to strengthen the existing TWR flyover. Bridge H is a separate bridge structure.  A short stub end between Grid H1 & H2 is stitched to the existing TWR flyover, but impact on it is very low.

(ii)        No reconstruction required on TK H/W piers.

(iii)      Bridge G: 5.11m vertical clearance to MTRC viaduct.  Bridge H: 2.3m horizontal clearance to TK H/W pier D7.  7.18m vertical clearance to TK H/W viaduct.

2

3

 

(i)          Bridge J is stitch joined (whole length) to the existing TWR flyover by the nearside lane while Bridge K is stitch joined (whole length) to the existing TWR flyover by the offside lane.  There could be a need to strengthen the existing TWR flyover.

(ii)        No reconstruction required on TK H/W piers.

(iii)      Bridge J: 5.11m vertical clearance to MTRC viaduct.  Bridge K: 0.69m horizontal clearance to TK H/W pier D7.  7.53m vertical clearance to TK H/W viaduct.

3

3A

(i)          Bridge L is stitch joined (whole length) to the existing TWR flyover by the nearside lane while Bridge M is stitch joined (whole length) to the existing TWR flyover by the offside lane.  There could be a need to strengthen the existing TWR flyover.

(ii)        No reconstruction required on TK H/W piers.

(iii)      Bridge L: 5.11m vertical clearance to MTRC viaduct.  Bridge M: 0.69m horizontal clearance to TK H/W pier D7.  7.53m vertical clearance to TK H/W viaduct.

3

* Ranking: 1 = most preferable & 3 = least preferable under this viewpoint

(VI)     Noise Mitigation Measure (NMM)

The comparison is focused on the design of the noise mitigation measures.  The critical factors to be considered are:

(i)            The design should minimize the impact on existing TWR flyover and, in particular, avoid additional loading put on this structure which was completed under earlier design standards.

(ii)          The design should minimize impact to traffic on adjacent roads and to other elements such as roadside slopes.

(iii)        Construction complexity.

         The factors taken into consideration in comparison of the options are described in the following table with the ranking determined accordingly:

Table 2-6      Consideration on Noise Mitigation Measure

Option

Factors

*Ranking

2

(i)         The NMM extends beyond the new bridge onto the new abutment.  There would be no impact on existing TWR flyover.

(ii)       The NMM can be constructed from the new bridge and from the new abutment.  Minimal impact on adjacent roads and other elements.

(iii)     The NMM is spanning approximately 7m over the new lane.  Construction complexity is low.

1

2A

(i)         The NMM extends beyond the new bridge onto the new abutment.  There would be no impact on the existing TWR flyover.

(ii)       The NMM can be constructed from the new bridge and from the new abutment.  Minimal impact on adjacent roads and other elements.

(iii)     Due to the wider bridge, the required span of the NMM is approximately 10m.  The required extent is also longer than Option 1A.

2

3

(i)         The NMM over both the new lane and the existing lanes of TWR.  Support from existing TWR flyover would be required.  Strengthening of TWR flyover is very likely required.  High impact on existing TWR flyover.

(ii)       Support (columns & foundations) would be required to be constructed on the roadside slopes in front of Fung King House.  Also, construction over existing roads will be required.  Disturbance to existing traffic is unavoidable.  High impact is anticipated on adjacent roads and other elements.

(iii)     The NMM is spanning over 5 lanes requiring a span of over 20m.  Construction complexity is much higher than other options.

3

3A

(i)         The NMM over both the new lane and the existing lanes of TWR.  Support from existing TWR flyover would be required.  Strengthening of TWR flyover is very likely required.  High impact on existing TWR flyover.

(ii)       Support (columns & foundations) would be required to be constructed on the roadside slopes in front of Fung King House.  Also, construction over existing roads will be required.  Disturbance to existing traffic is unavoidable.  High impact is anticipated on adjacent roads and other elements.

(iii)     The NMM is spanning over 5 lanes requiring a span of over 20m.  Construction complexity is much higher than other options.

3

* Ranking: 1 = most preferable & 3 = least preferable under this viewpoint

(VII)  Utilities and Drainage Impact

In construction stage especially foundation construction, there would be impact to the utilities in the Project area. Permanent diversion and local realignment of the existing utilities would be required. The existing utilities potentially to be affected include drainage and sewage system, electrical power supplies, watermains, lighting systems and telecom utilities. For other underground obstructions such as the box culvert and the foundation of existing bridges, no significant difference is anticipated among the options. Comparisons among the options are made based on the major impacts identified in the UIA Report under this Project as below:

(i)            There are high voltage power cables i.e. 132kV laid under the footprint of the proposed alignment options and would be affected during foundation construction.

(ii)          Piers and foundation will be located within the drainage reserve which requires seeking agreement from DSD.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly:

 

Table 2-7      Consideration on Bridge Scheme

Option

Factor

*Ranking

2

(i)         132kV cable near Grids E1 to E5, F3 piers & F8 abutment (6 piers + abutment wall)

(ii)       2 piers (Grid E4-E5) located within drainage reserve. Impact is considered as minor.

1

2A

(i)         132kV cable near Grids G1 – G5, H3 piers & H8 abutment (6 piers + abutment wall)

(ii)       2 piers (Grid G4-G5) located within drainage reserve. Impact is considered as minor.

1

3

(i)         132kV cable near Grids J1 – J5, J7, K1, K2 piers & K6 abutment (8 piers + abutment)

(ii)       2 piers (Grid J4-J5) located within drainage reserve. Impact is considered as minor.

2

3A

(i)         132kV cable near Grids L1 – L5, L7, M1, M2 piers & M6 abutment (8 piers + abutment)

(ii)       2 piers (Grid L4-L5) located within drainage reserve. Impact is considered as minor.

2

* Ranking: 1 = most preferable & 2 = least preferable under this viewpoint

(VIII)                        Impact on Other Elements

The existing footbridge NF303 currently serves as a main access for pedestrians crossing KCR. Under some of the road improvement options, this footbridge NF303 would be modified or reconstructed. Moreover, there is a pedestrian subway (NS10A), providing access under KCR to Lai King Estate. The subway would be required to be extended to cater for widening the KCR downramp.   

The ranking factors to be considered on other main elements affected by the Project would be as shown below:

(i)            Footbridge NF303: For comparison purpose, the surface area of proposed reconstructed footbridge [Afootbridge] was estimated for each option.

(ii)          Subway NS10A: For comparison purpose, the surface area of proposed extension to subway [Asubway] was estimated for each option.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly:

Table 2-8      Consideration on Other Elements

Option

Factor (i)

[Afootbridge]

Factor (ii)

[Asubway]

*Ranking

2

440 sq m

Nil

1

2A

440 sq m

Nil

1

3

440 sq m

15 sq m

3

3A

440 sq m

9 sq m

2

* Ranking: 1 = most preferable & 3 = least preferable under this viewpoint


Other Considerations

(IX)     Land Requirements

Based on the latest land status plan, all proposed works in the seven options are either within Government land lots or public roads. The major lands to be affected in the Project area and its status are listed as follows:

(i)            The amount of land (otherwise available for other use) sterilized by works under this Project.  For comparison purpose, the area within land lots [Alot] was estimated for each option.

-    Lot No. STT3706K&T STT:  Short term tenancy for car parking use

-    Lot No. GLA-TKT 1726 TGLA: Temporary Government land allocation to Public Works Laboratory until 23 June 2016

(ii)          The impact on the existing feature, i.e. Public Works Laboratory within Lot No. GLA-TKT 1726 TGLA (in terms of the two buildings’ footprint) in the construction stage of the Project.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly:

Table 2-9      Consideration on Land Requirement

Option

Factor (i)[Alot]

Factor (ii)

*Ranking

2

 

1810 sq m

(535 sq m of Lot No. STT3706K&T STT and

1275 sq m of Lot No. GLA-TKT 1726 TGLA)

Affected

3

2A

 

1810 sq m

(535 sq m of Lot No. STT3706K&T STT and

1275 sq m of Lot No. GLA-TKT 1726 TGLA)

Affected

3

3

 

1715 sq m

(615 sq m of Lot No. STT3706K&T STT and

1100 sq m of Lot No. GLA-TKT 1726 TGLA)

Affected

2

3A

1707 sq m

(612 sq m of Lot No. STT3706K&T STT and

1095 sq m of Lot No. GLA-TKT 1726 TGLA)

Affected

1

* Ranking: 1 = most preferable & 3 = least preferable under this viewpoint

(X)        Environmental Impacts

In evaluating the recommended road improvement option, the comparison of major environmental impacts (noise and air quality) generated from the road against all options is mainly focused.  The anticipated differences among the options are listed as factor for comparison:

(i)     Noise Impact

Noise impacts during construction and operation phases are taken into consideration.

(a)       Construction phase – the necessity of lengthy night time construction, the distance from works area boundary to NSRs, and site area
(b)      Operation phase – the noise level from the roads to NSRs. Assumption of providing noise enclosure in all options is made for comparison.

(ii)   Air Quality Impact

The different physical alignments would impose different separation distance among sources and receivers and hence lead to variation on pollutant dispersion.  Therefore, comparison of air quality impact during construction and operation phases is to be made through the consideration of separation distance.

(a)       Construction phase – potential dust impacts generated from different options are generally similar. No significant difference is anticipated.
(b)      Operation phase – separate distance

(iii) Landscape and Visual Impacts

In view of the similar nature of works and work areas between different options, no significant difference is anticipated in comparison.

The factors taken into consideration in comparison of the options are described in the below tables with the ranking determined accordingly.

Table 2-10a  Consideration on Environmental Impacts

Option

Factor (i) – Noise Impact

Factor (ii) – Air Quality Impact

2

(a)    Works area boundary is around 30m from the closest NSR

(a)    Air quality impact to be mitigated on site

(b)   Noise from the proposed flyover is mitigated.

(b)   Around 30m separation distances from additional traffic lane to Fung King House and around 60m to Lai King Catholic Secondary School.

2A

(a)    Works area boundary is around 30m from the closest NSR.  Works area is larger than Option 2.

(a)    Air quality impact to be mitigated on site

(b)   Noise from the proposed flyover is mitigated.

(b)   Around 30m separation distances from additional traffic lane to Fung King House and around 60m to Lai King Catholic Secondary School.

3

(a)    Partial noise enclosure construction anticipated over existing roads.  Considerable amount of night time construction works anticipated and in close proximity to Fung king House.  Significant construction noise impact is anticipated.

(a)    Air quality impact to be mitigated on site

(b)   Noise from the proposed flyover and section of KCR is mitigated.

(b)   Shortest separation distance among all options.

3A

(a)    Partial noise enclosure construction anticipated over existing roads.  Considerable amount of night time construction works anticipated and in close proximity to Fung king House.  Significant construction noise impact is anticipated.

(a)    Air quality impact to be mitigated on site

 

(b)   Noise from the proposed flyover and section of KCR is mitigated.

(b)   Shortest separation distance among all options.

 

Table 2-10b  Rankings of Factors of Environmental Impacts

Option

*Sub-ranking of Factor (i)(a)

*Sub-ranking of Factor (i)(b)

**Sub-ranking of Factor (ii)(a)

*Sub-ranking of Factor (ii)(b)

**Sub-ranking of Factor (iii)

*Overall Ranking

2

1

2

-

1

-

1

2A

2

2

-

1

-

2

3

3

1

-

2

-

3

3A

3

1

-

2

-

3

* Ranking: 1 = most desirable and 3 = least desirable

** No significant difference

(XI)     Capital and Recurrent Cost

The annual recurrent expenditure arising from the proposed structures is taken into account in evaluation of options. The proposed items induced the most capital and recurrent costs are mainly the highway structures, which are:

(i)            The extent of the bridge works.  For comparison purpose, the surface area of bridge deck [Adeck] was estimated for each option.

(ii)          The extent of the noise mitigation measures. For comparison purpose, the surface area of noise mitigation measures [Anmm] was estimated for each option.

(iii)        The extent of other major items of works.  With the proposed options, the major items of works include:

-    Footbridge NF303.  For comparison purpose, the surface area of proposed reconstructed footbridge [Afootbridge] was estimated for each option.

-    Subway NS10A.  For comparison purpose, the surface area of proposed extension to subway [Asubway] was estimated for each option.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly:

Table 2-11    Consideration on Capital and Recurrent Cost

Option

Factor (i)

[Adeck]

Factor (ii)

[Anmm]

Factor (iii)

*Ranking

2

 

2630 sq m

3455 sq m

(a)  Afootbridge = 440 sq m

(b)  Asubway = Nil

1

2A

 

3919 sq m

5402 sq m

(a)  Afootbridge = 440 sq m

(b)  Asubway = Nil

2

3

 

2340 sq m

8615 sq m

(a)  Afootbridge = 440 sq m

(b)  Asubway = 15 sq m

4

3A

2066 sq m

7940 sq m

(a)  Afootbridge = 440 sq m

(b)  Asubway = 9 sq m

3

* Ranking: 1 = most preferable & 4 = least preferable under this viewpoint

 

(XII)  Maintenance Consideration

Maintenance is one of the considerations of evaluation and assessment on an alignment scheme. It can be evaluated by analyzing the maintainability of the proposed items (serviceability and reparability), future maintenance cost and time. The comparison is focused on the maintenance consideration of special features of the bridges which controls the maintenance cost and require particular inspections, and the provision of clearance for maintenance (i.e. min. 2m between existing and proposed structures).

(i)            Stitched joint requires special attention on maintenance.  For comparison purpose, the length of stitched joint [Lstitch] was estimated for each option.

(ii)          Provision of min. clearance between existing and proposed structures.

The factors taken into consideration in comparison of the options are described in the table below with the ranking determined accordingly:

Table 2-12    Consideration on Maintenance Consideration

Option

Factor (i)[Lstitch]

Factor (ii)

*Ranking

2

190 m

>2 m

1

2A

190 m

>2 m

1

3

500 m

<2 m

3

3A

486 m

<2 m

2

* Ranking: 1 = most preferable & 2 = least preferable under this viewpoint

(XIII)                        Time for Completion

The estimation of the construction time depends on many factors such as the nature of proposed structures, construction methods, site constraints, etc. For evaluation and assessment of the optimal scheme, the following critical factors are considered. Other constructions such as the utility diversion, re-provision of footbridge and extension of subway will likely be carried out in parallel with the major works. Hence, the influence to the construction programme is considered as minor.  

(i)            The extent of the bridge works.  For comparison purpose, the surface area of bridge deck [Adeck] was estimated for each option.

(ii)          The extent of the noise mitigation measures. For comparison purpose, the surface area of noise mitigation measures [Anmm] was estimated for each option.

(iii)        The complexity of the construction.  With the proposed options,  construction will be more complex for option(s) involving:

-    Reconstruction of TK H/W pier(s).  For comparison purpose, the number of pier to be reconstructed was counted.

-    Bridge deck(s) that requires stitch-jointing to existing upramp.  For comparison purpose, the length of stitch joint [Lstitch] was estimated.

-    Construction of noise mitigation measures adjacent to / over operational roadways.  For noise mitigation measures to be installed on newly proposed bridge(s), the complexity of construction is considered to be lower.

The factors taken into consideration in comparison of the options are described in the below table with the ranking determined accordingly:

Table 2-13    Consideration on Time for Completion

Option

Factor (i)

[Adeck]

Factor (ii)

[Anmm]

Factor (iii)

*Ranking

 

2

 

2630 sq m

3455 sq m

(a)  Nil

(b)  190m

(c)  Some length beyond Gird F8

1

2A

 

3919 sq m

5402 sq m

(a)  Nil

(b)  190m

(c)  Considerable length beyond Gird H8

2

3

 

2340 sq m

8615 sq m

(a)  Nil

(b)  500m

(c)  Very long length between J1 & K4

4

3A

2066 sq m

7940 sq m

(a)  Nil

(b)  486m

(c)  Very long length between L1 & M4

3

* Ranking: 1 = most preferable & 4 = least preferable under this viewpoint

Overall Ranking & Recommendation

2.8.2             For each of the viewpoints, the major factors that affect ranking of the road improvement options have been identified, compared and documented in the “Report on the Development and Evaluation of Options” report.  These viewpoints have been selected to give an overall consideration on the options. 

2.8.3             Some viewpoints, such as “Traffic & Other Operational Consideration”, would be of higher importance than others. The traffic factors are considered as the core of this Project as to improve the existing road section to cope with the future traffic growth. The existing site constraints and strengthening of the structures also critically govern the feasibility of alignment options. Therefore “Engineering Consideration” is considered as secondary and followed by other considerations. (i.e. weighting order for the viewpoints: Traffic & Other Operational Consideration > Engineering Consideration > Other Considerations).

2.8.4             Base weighting for the viewpoints are described below:

·      Traffic & Other Operational Consideration – Both the “Permanent Traffic Arrangement” and the “Alignment Design Standard” factors critically affect the final performance of the improvement.  The “Traffic Impact at Construction Stage” is important in that the already congested TWR should not be critically affected during construction.  To summarize, this viewpoint is the determining factor and is therefore assigned a more than pass mark percentage of 55%.

·      Engineering Consideration – This viewpoint compares the pros and cons on the engineering scheme of the road improvement options and is assigned a percentage of 25%.

·      Other Consideration – The factors under this viewpoint generally compare the road improvement options in a boarder sense.  This viewpoint is assigned a percentage of 20%.

 

2.8.5             Based on the above weighting (55%:25%:20%), sub-weighting for the factors under each viewpoint are determined.  The overall marking and overall ranking are illustrated below:

              Table 2-14    Overall Marking and Overall Ranking for Identified Options

              Viewpoints

Weighting

Options

Base

Sensitivity Tests

1

1A

2

2A

2B

3

3A

A

B

C

D*

Traffic & Other Operational Consideration

55%

50%

60%

50%

50%

Failed screening-weaving analysis

Failed screening-weaving analysis

 

 

Failed screening-road vert. clearance check

 

 

i.     Permanent Traffic Arrangement

20%

20%

20%

20%

20%

1

1

1

2

ii.    Alignment Design Standard

25%

20%

30%

20%

20%

3

1

2

1

iii.   Traffic Impact at Construction Stage

5%

5%

8%

5%

5%

1

2

3

3

iv.   Other Operational Consideration

5%

5%

2%

5%

5%

2

2

2

1

Engineering Consideration

25%

30%

20%

27%

25%

 

 

 

 

v.    Bridge Scheme

8%

10%

7%

9%

8%

1

2

3

3

vi.   Noise Mitigation Measure

8%

10%

7%

9%

8%

1

2

3

3

vii.  Utilities and Drainage Impact

5%

5%

3%

5%

5%

1

1

2

2

viii. Impact on Other Elements

4%

5%

3%

4%

4%

1

1

3

2

Other Considerations

20%

20%

20%

23%

25%

 

 

 

 

ix.   Land Requirements

3%

4%

4%

3%

3%

3

3

2

1

x.    Environmental Impacts

5%

4%

4%

8%

10%

1

2

3

3

xi.   Capital and Recurrent Cost

5%

4%

4%

5%

5%

1

2

4

3

xii.  Maintenance Consideration

5%

4%

4%

5%

5%

1

1

3

2

xiii. Time for Completion

2%

4%

4%

2%

2%

1

2

4

3

Overall Mark - Base Weighting:

 

 

1.61

1.44

 

2.29

2.00

Overall Mark – Sensitivity Test A:

1.53

1.50

2.34

2.08

Overall Mark – Sensitivity Test B:

1.70

1.44

2.29

1.98

Overall Mark – Sensitivity Test C:

1.51

1.49

2.34

2.10

Overall Mark – Sensitivity Test D:

1.51

1.49

2.34

2.10

Overall Ranking :

2

1

4

3

                  Remarks:   Low score & rank 1= most preferable;

                                    High score & rank 4= least preferable

                                    * Hypothetic sensitivity test for Environmental Impacts

 

2.8.6             Option 2A is ranked as the most preferable road alignment option in accordance with the selected base weighting. Furthermore, Sensitivity Tests A to D with different weightings are conducted and shown in Table 2.14 above. Sensitivity Test D is a hypothetic testing with a relatively higher percentage to “Environmental Impacts”. It is found that the overall ranking among the options remains the same order.

2.8.7             Given that the sub-ranking of Environmental Impacts in Option 2 is more preferable than the recommended Option 2A, the two options are actually quite similar. The main differences are the design speed and the width of the bridge. Option 2A introduces a larger structure footprint at construction phase. Nonetheless during operation phase, it may have better air quality under a higher vehicle speed scenario.

Conclusion

2.8.8             The alternative road improvement options are described under Section 2.6 of this Report.  Based on weaving analysis from traffic impact assessment, Options 1 and 1A were considered infeasible and were not taken into consideration in the ranking.  Option 2B was also not further considered due to infeasibility on the bridge scheme. Viewpoints have been set out in Section 2.8.1 above and the major factors that affect ranking of the road improvement options have been identified and compared. With weighting for each viewpoint established in Table 2.14 above, the recommended option is Option 2A - Separate Viaduct Option on West Side of TWR (Design Speed 70km/hr).

2.8.9             Option 2A is considered the best road improvement option based on the fact that this scheme will yield the best traffic performance upon its implementation.  The additional lane in this scheme is to occupy one of the segregated lanes of KCR.  From results of traffic survey, there is over one full lane of capacity to receive this additional lane.  With respect to the compliance on alignment design standard, this Option 2A is in compliance on all aspects.  The required construction, such as the bridges and the noise mitigation measures, is less extensive than that required under Option 3 and 3A but is only marginally more extensive than Option 2.  Bridge G is required to be stitch-jointed to existing TWR flyover.  To minimize differential movement, the bearing types and their positioning are proposed to be in line with the existing structure.  Subsequent liaison and agreement with the authorities are to be made.

2.9                   Construction Method and Engineering Requirements

2.9.1             This section introduces the key aspects of the works and the planning of the construction.

2.9.2             The construction of the recommended alignment Option 2A under this Project mainly involves a separate flyover structure connecting KT I/C upramp to KCR, widening of TWR, installation of noise barriers on the aforementioned proposed structures, demolition and reprovision of existing footbridge NF303, demolition of existing Public Works Regional Laboratory (subject to the termination of the allocation), relocation of the bus stop outside subway NS10A and associated works such as utility diversion, street lighting and landscaping works.

Flyover from KT I/C Upramp to KCR

2.9.3             The proposed link connecting TWR and KCR is a flyover in the form of a single cell prestressed concrete box girder. It consists of seven spans (maximum span of 54m) supported by piers and end abutments. The flyover is expected to be constructed by cast in-situ method.

2.9.4             The proposed flyover will be stitched to the TWR flyover deck to avoid forming a longitudinal joint between the existing structure and the flyover. The monolithic stitched joint will be constructed at the latest stage after completion of the superstructure of the proposed flyover to link the two structures together.

2.9.5             Before the viaduct construction can commence, utility diversions will be required at pier and abutment locations.

2.9.6             The proposed flyover spans over KCR and Container Port Road South and goes under TK H/W. Sufficient horizontal clearance of minimum 2m will be maintained between the proposed flyover and the existing piers.

2.9.7             The piers are made of reinforced concrete supported on piled foundations. Piling construction will be either bored piles or pre-bored H-piles.

Widening of TWR at the Existing Upramp

2.9.8             A short section of Kowloon-bound TWR near existing KT I/C upramp will be widened. It is proposed to construct a new deck adjacent and parallel to the existing TWR bridge deck. The gap between the new and existing decks will be closed by a cast in-situ concrete stitch. To minimize the detrimental effect from the traffic vibration on the strength development and the structural integrity of the concrete stitch, concreting of the stitch will be carried out at night and one traffic lane of TWR will be temporarily closed. The structural articulation of the new deck will be compatible with the existing deck.

2.9.9             The new deck will be supported on reinforced concrete piers and portal frames spanning across the drainage reverse zone underneath. Public Works Regional Laboratory (Tsuen Wan) is in the vicinity of the proposed bridge work. Having considered works area for construction of the proposed bridge work and direct impacts to the laboratory buildings, temporary occupation of the laboratory area is required during the construction. The allocation of the land will be terminated before the commencement of the construction of this Project. The area will be reinstated by the allocatee (i.e. CGE/Standards & Testing, CEDD) to Lands Department according to the engineering condition.

Demolition and Reprovision of Existing Footbridge NF303

2.9.10         As the existing footbridge NF303 is in conflict with the proposed flyover, relocation of the footbridge is necessary. The new footbridge will be constructed to maintain the pedestrian access across KCR prior to demolition of the existing footbridge. The structural form of the new footbridge will be similar to the existing, i.e. warren truss steel bridge girder. Lifts will be provided in compliance with the guideline of barrier free access.

2.9.11         Foundation work will commence first.  The abutments, piers and table tops construction will follow. The truss steel bridge girder is expected to be fabricated off site. The activity of lifting the bridge girders by the mobile crane will be carried out at night in accordance with the TTA scheme. The temporary closure of the KCR is expected. Construction of the footbridge’s furniture, lift tower and staircases will follow.

2.9.12         Once the new footbridge is completed and opened to public, the demolition of the existing footbridge will commence. All non-structural elements such as roof panels and handrails will be firstly removed. The steel truss will be removed at night with temporary road closure. To dismantle the remaining structures including table tops, piers, staircases and abutments, metal scaffolding platform and protective enclosure will be erected.

Construction of Noise Barriers

2.9.13         The noise barriers (a combination of 5.5m high vertical, 5.5m high with 2.5m cantilevered barrier at 45 degree and 5.5m high with 3.5m cantilevered barrier at 45 degree types) are to be provided on the proposed flyover.


2.10               Works Programme

2.10.1         Construction of the Project should be commenced tentatively in 2018 and complete in 2021.  The tentative construction programme of the Project is shown on Appendix 2.1.

2.11               Concurrent Project

2.11.1         There are six concurrent projects in the vicinity of the Project’s works area, as summarized in Table 2.15.

Table 2-15    Major Concurrent Projects

Project

Planned Construction Period

Tsuen Wan Bypass, Widening of Tsuen Wan Road between Tsuen Tsing Interchange and Kwai Tsing Interchange, and associated Junction Improvement Works: and Retrofitting of Noise Barriers on Tsuen Wan Road

The implementation of Tsuen Wan Bypass is uncertain at this stage.

Widening of Yeung Uk Road between Tai Ho Road and Ma Tau Pa Road, Tsuen Wan

No physical interface

Replacement and Rehabilitation of Water Mains Stage 4, Mains in New Territories

The works are within the site boundary but the construction is Feb 2012-Nov 2015 which is before our tentative construction programme.

Extension of Footbridge Network in Tsuen Wan

No physical interface

Cycle Track between Tsuen Wan and Tuen Mun

No physical interface

Reconstruction and Improvement of Tuen Mun Road

No physical interface

Planned Landslip Prevention and mitigation works for a man-made slop (feature no. 11NW-A/C516) located at Lai King Hill Road near Ha Kwai Chung Polyclinic

Works will be carried out within the period from January 2013 to December 2014 that before our tentative construction programme.

 

2.11.2         At this stage, consideration of concurrent projects for cumulative environmental will only takes into account those with available implementation programmes.  Cumulative impacts from the concurrent projects, if any, have been assessed in the individual sections of this EIA study.