2 PROJECT DESCRIPTION.. 1
2.1 Site Location. 1
2.2 EIA Study Area. 1
2.3 Review of Previous EIAs. 3
2.4 Project Requirements,
Scope and Benefits. 13
2.5 Consideration of
Alternatives and Development of Preferred Option. 13
2.6 Construction Methods and
Engineering Requirements. 13
2.7 Operation of the Project 13
2.8 Works Programme. 13
List of Tables
Table 2.1 Comparison of Trunk Road
Tunnel Variations. 22
Table 2.2 Comparison of Tunnel and
Flyover Options. 25
2
PROJECT DESCRIPTION
2.1
Site Location
2.1.1
The
Project is located mainly in Wan Chai North, Causeway Bay and North Point, and is demarcated by Gloucester Road and Victoria Park Road to the south, Fenwick Pier Street
to the west and Tong Shui Road Interchange to the east, as shown in Figure 1.1.
2.1.2
The
study area encompasses existing developments along the Wan Chai, Causeway Bay and North Point shorelines.
Major land uses include the HKCEC Extension,
the Wan Chai Ferry Pier, the ex-PCWA, the Royal Hong Kong Yacht Club (RHKYC),
the Police Officers' Club, the CBTS and commercial and residential
developments.
2.2
EIA Study Area
2.2.1
The
following definitions of the study areas have been adopted with reference to
the EIA Study Brief registered under the EIAO:
·
Air
Quality Impact: the assessment area should include the area within 500 m from the boundary of the Project;
·
Noise
Impact Assessment: the assessment area should include the area within 300 m from the boundary of the Project;
·
Water
Quality Impact Assessment: the assessment area should include the areas within
and 300m extended beyond the boundary of the Project, plus the Victoria Harbour
Water Control Zone (WCZ), the Eastern Buffer WCZ and the Western Buffer WCZ as
declared under the Water Pollution Control Ordinance;
·
Waste
Management: the assessment will focus on areas within the boundary of the
Project;
·
Land
Contamination: the assessment area for land contamination impact will include
the A King Shipyard at the CBTS and any other potentially contaminated sites
identified in this EIA;
·
Landscape
and Visual Impact: the area for
landscape impact assessment should include all areas within 100 m extended from the boundary of the Project, while the assessment area
for the visual impact assessment should be defined by the visual envelope from
the Project and associated works;
·
Marine
Ecology: the assessment for marine ecological impact will focus on the area
within the Project boundary; and
·
Cultural
Heritage Impact: the assessment for cultural heritage impact will focus on the
area within the Project boundary.
2.3
Review of Previous EIAs
Description
of Project Details
2.3.1
Under
the Project, permanent reclaimed land will be formed along the existing Wan
Chai and North Point shorelines for the construction of the Trunk Road. At the same time, an attractive
waterfront with a new public promenade will be provided. A total reclamation area of 12.7 ha is envisaged, with the newly reclaimed land forming a narrow strip of
land along the existing Wan Chai shoreline from the interface with the CRIII
project west of the HKCEC Extension, along the Wan Chai shoreline up to the
west of the ex-PCWA basin, and along the North Point shoreline from the east of
the CBTS to the west of City Garden (Figure 1.1). The Project will also include roads,
pedestrian links to the waterfront, including footbridges and landscape decks,
a new cross-harbour water mains from Wan Chai to Tsim Sha Tsui and a new sewage
outfall from the Wan Chai East Sewage Screening Plant, reprovisioning of
affected facilities including drainage outfalls, cooling water intakes, WSD's
salt water pumping station, ferry pier, helipad, etc, and waterfront promenade
landscaping. During the Trunk Road
construction, temporary reclamation will be required in the ex-PCWA basin and
the CBTS to facilitate cut-and-cover tunnel construction of the Trunk
Road. Existing moorings in the CBTS
will need to be relocated temporarily outside the CBTS. After construction of the Trunk Road,
the temporary reclamation will be removed and the ex-PCWA basin and the CBTS
will be reinstated.
2.3.2
In
reviewing the change of scope and extent of the elements of the Project from
what was originally proposed, and which was covered by the approved WDIICFS and
CWB&IECL EIA Reports under the EIAO in 2001, the changes are confined to
the nature and extent of the Trunk Road and associated ground level roads, Road
P2, and the extent of reclamation.
As the original schemes for the cross-harbour water mains and the sewage
outfall have not changed materially, the related EIA assessments of the
approved EIA Report for the WDIICFS for these works remain valid. This EIA study focuses mainly on those
elements of the Project that have changed significantly from the schemes as
presented in the approved EIA Reports.
For the dredging for the cross-harbour water mains and the sewage
outfall, this EIA Study has still included the cumulative impact assessment,
updated the assessment assumptions and the corresponding mitigation measures.
2.3.3
The
extent of the Trunk Road covered by the approved EIA Report on the CWB &
IECL includes the Central Interchange in Central Reclamation Phase I (CRI), the
Trunk Road tunnel that runs through CRIII and partly through WDII (extending to
the location of the ex-PCWA basin), and the IECL through WDII connecting the
Trunk Road tunnel to the IEC at the eastern end of the CBTS. It should be noted that it is only the
section of the Trunk Road through WDII that is subject to change under the WDII
Review. As the original scheme for
the Trunk Road through CRI and CRIII has not changed, findings and recommended
mitigation measures of the approved EIA Report for the Trunk Road within the
CRI and CRIII areas remain valid. The relevant environmental
findings and recommended mitigation measures are captured from the approved EIA
Report and summarised below.
2.3.4
This
EIA study is confined to the elements that have changed significantly from the
scheme as presented in the approved EIA Report for the CWB&IECL, viz. the
Trunk Road tunnel through WDII and its connection to the existing IEC (Figure 1.1). A comparison table comparing the original
scheme of WDII and CWB under the approved EIA Report on Wan Chai Development
Phase II (Application No. EIA-058/2001) and on the Central-Wan Chai Bypass and Island Eastern Corridor Link (Application No. EIA-057/2001) and the present scheme under the EIA
Study for WDII & CWB projects (EIA Study Brief No. ESB-153/2006) is given
in Appendix 2.1.
Review of
Previously Approved CWB&IECL EIA Report
2.3.5
The previous key EIA findings, impact predictions and
recommendations as stipulated in the approved CWB&IECL EIA Report are
considered valid for the Central Interchange in CRI and the Trunk Road tunnel
that runs through CRIII. The
relevant implementation schedule of the proposed mitigation measures for the
CWB within CRI and CRIII as extracted from the approved CWB&IECL EIA Report
is given in Appendix 2.2.
2.3.6
The construction activities at Central Interchange and
CRIII remain the same as those given in the approved CWB&IECL EIA
Report. There will be tunnel,
bridge, tunnel building construction and demolition of part of Rumsey Street
Flyover at Central Interchange area.
There will be CWB tunnel construction at the CRIII area. The preliminary design of the West Ventilation
Building (including minimum discharge height, exhaust
directions, handling capacity and exit velocity) as given in the approved
CWB&IECL EIA Report remains materially unchanged. The related EIA assessments of the approved
CWB&IECL EIA Report for these works therefore remain valid.
2.3.7
The sensitive receivers from Sheung Wan through
Central as identified in the approved CWB&IECL EIA Report are unchanged.
2.3.8
The existing air sensitive receivers from Sheung Wan
through Central will be protected from adverse construction air quality impact
by the recommended dust control measures during construction phase. The recommended mitigation measures for
dust control include:
·
strictly limit the truck speed on site to below 10km per hour and water spraying to keep the haul
roads in wet condition;
·
twice daily watering of the work site with active
operations when the weather and the work site are dry;
·
watering during excavation and material handling;
·
provision of vehicle wheel and body washing facilities
at the exist points of the site, combined with cleaning of public roads where
necessary; and
·
tarpaulin covering of all dusty vehicle loads
transported to, from and between site locations.
2.3.9
With no increase in the proposed tunnel portals and
ventilation building emissions, and the same traffic pattern at the Central
Interchange area, the air quality assessment from the previous CWB&IECL
approved EIA is still valid for the operation phase. No adverse operational air quality
impacts at the existing and planned air sensitive receivers from Sheung Wan to
Central are predicted and mitigation measures are not considered
necessary. For the air pollution
within the tunnel section in CRIII, monitoring of tunnel air quality will be
required to ensure the acceptability of the tunnel air quality criteria.
2.3.10
The existing noise sensitive receivers from Sheung Wan
through Central, including Korea Centre, City Hall and PLA Headquarters, will
be protected from adverse construction noise impact by the recommended noise
mitigation and control measures during construction phase. The mitigation measures during
construction phase include:
·
The use of silenced powered mechanical equipment
(PMEs) for the following construction tasks:
-
piling, tunnel and deck construction at Mass Transit
Railway tunnel crossing area;
-
west ventilation building; and
-
demolition of downramp of Rumsey
Street.
2.3.11
For the operation phase, no direct noise mitigation
measures are required from Sheung Wan to Central for the three noise sensitive
receivers, Korea Centre, City Hall and PLA Headquarters for the new trunk road and slip roads at
Central Interchange. The Trunk Road
in CRIII is in tunnel and no direct mitigation measures are required. The findings and recommendations of the
approved CWB&IECL EIA Report in respect of noise are still valid.
2.3.12
As no reclamation will be undertaken directly for the
CWB at the Central Interchange (reclamation for the CWB through CRIII is
addressed in the approved CRIII EIA Report), the primary concern with regard to
water quality will be the control of runoff during construction. This could potentially contain elevated
constructions of suspended solids (SS), and could impact upon the flushing and
cooling water intakes located along the Victoria Harbour waterfront, identified as potential sensitive
receivers. However, the potential
water quality impacts could be controlled to comply with the WPCO standards by
implementing the recommended implementation measures, including provision of
drainage facilities, oil and silt removal facilities and good site
practices. No unacceptable residual
water quality impact is anticipated.
2.3.13
Mitigation measures, including road drainage with silt
traps and petrol interceptors, are also recommended to remove oil and grease
from the road runoff during operation.
No unacceptable residual water quality impact is expected. The findings and recommendations of the
approved CWB&IECL EIA Report in respect of water quality are still valid.
2.3.14
Provided that waste arising from the construction of
the CWB at Central Interchange and CRIII areas are handled, transported and
disposed of using approved methods as recommended in the approved CWB&IECL
EIA Report, and that no solid or liquid wastes enter nearby marine waters, no
unacceptable environmental impacts are envisaged. These recommended methods
include segregation of wastes, water minimization, and good site practices for
storage, collection and transport of waste during construction. The estimated
quantity of excavated material from the Central Interchange and west tunnel
building are unchanged. The
mitigation measures recommended in the approved CWB&IECL EIA Report should
be incorporated into contract specifications to ensure that environmental
nuisance will not arise from the storage, transport and disposal of various
types of waste arising from the construction of the CWB project. These recommendations should form the
basis of the site Waste Management Plan to be developed by the Contractor at
the construction stage. The
findings and recommendations of the approved CWB&IECL EIA Report in respect
of waste management are still valid.
2.3.15
Key
issues relating to the impact on the landscape and visual context of the
proposed road include the loss of existing vegetation, the addition of
infrastructure associated facilities (west ventilation building), associated
works (portals, wing walls and abutments), and elevated road sections at
Central Interchange and CRIII areas.
2.3.16
The
potential impacts during the construction phase are:
·
Moderate adverse residual landscape impacts would
occur through vegetation removal at the western above-ground sections of CWB.
·
Significant adverse residual visual impacts would
occur along the CWB from buildings with a harbour outlook around the Central
Interchange and CRIII areas.
Moderate adverse impacts on visually sensitive receivers with distant
views from Tsim Sha Tsui waterfront.
2.3.17
The potential impacts during the operational phase
are:
·
The extended Rumsey Street Flyover and its associated
elevated slip road are located further west from the proposed Central
waterfront promenade. Thus, they
have negligible residual landscape impact to the planned waterfront promenade.
·
The Central area will have significant adverse
residual visual impact at residential units at Shun Tak Centre. Moderate / significant adverse residual
visual impact would occur at the Airport Railway Hong Kong Station Northern
Site Development (the IFC and Four Seasons Hotel) due to the close view of the
elevated road structures.
2.3.18 The
overall residual landscape and visual impact after the implementation of the
recommended mitigation measures will be moderate adverse. In the context of Annex 10 of the
EIAO-TM, the landscape and visual impacts are considered acceptable with
mitigation measures. The findings
and recommendations in the approved CWB&IECL EIA Report in respect of
landscape and visual impacts are still valid.
2.3.19 In
summary, the relevant findings and recommendations of the approved CWB&IECL
EIA Report for the CWB within the Central Interchange and CRIII areas have been
reviewed and are found to be still valid.
Review of
Previously Approved WDIICFS EIA Report
2.3.20
The previously approved WDIICFS EIA Report covers a
Schedule 3 DP for an engineering feasibility study of an urban development
project with a study area covering more than 20ha and five individual Schedule 2 DPs as
summarised below:
·
Reclamation works including associated dredging works
·
WDII major roads (including Road P2)
·
Wan Chai East Sewage Outfall
·
Kellet Island
Marina
·
Dredging for the Cross-harbour Water Mains from Wan
Chai to Tsim Sha Tsui
2.3.21
As the original schemes for the sewage outfall and
cross-harbour water mains from Wan Chai to Tsim Shai Tsui have not changed, the
related EIA assessments of the approved EIA Report for the WDIICFS for these
works are therefore considered to remain valid.
2.3.22
The reclamation works and the WDII major road works
have changed significantly since the WDIICFS. The EIA assessments for these works shall
therefore refer to this current WDII&CWB EIA Report.
2.3.23
The cumulative impacts of the sewage outfall, the
cross-harbour water mains, the reclamation works and major road works have also
been reassessed in this current WDII&CWB EIA.
2.3.24
There is no Kellet Island Marina in the current scheme
and hence it is not included in this WDII&CWB EIA Report.
2.3.25
As presented in paragraph 1.6 above, this WDII&CWB
EIA Report covers the Schedule 3 DP for an engineering feasibility study of an
urban development project with a study area covering more than 20ha, while the individual Schedule 2 DPs have been
updated as below:
·
Central-Wanchai Bypass including its road tunnel and
slip roads
·
Road P2 and other roads which are classified as
primary/district distributor roads
·
Reclamation works including associated dredging works
·
Temporary typhoon shelter
·
Wan Chai East Sewage Outfall
·
Dredging for the Cross-harbour Water Mains from Wan
Chai to Tsim Sha Tsui
2.3.26
During reclamation, filling and surcharging were
identified as the major dust sources and entrusted works of the CWB tunnel
section would also cause potential dust nuisance during excavation and backing
as stated in the WDIICFS EIA Report.
This will also be the case for the revised scheme as identified in the
WDII&CWB EIA Report and is incorporated in the air quality assessment in
Section 3 of this report.
2.3.27
In order to achieve the air quality objectives, the
following dust suppression measures were suggested in the WDIICFS EIA Report:
·
strictly limit the truck speed on site to below 10 km per hour and water spraying to keep the haul
roads in wet condition;
·
twice daily watering of the work site with active
operations when the weather and the work site are dry;
·
watering during excavation and material handling;
·
provision of vehicle wheel and body washing facilities
at the exit points of the site, combined with cleaning of public roads where
necessary; and
·
tarpaulin covering of all dusty vehicle loads
transported to, from and between site locations.
The air quality assessment of the WDII&CWB EIA
Report has considered the above recommendations and they are incorporated as
mitigation measures to suppress dust during the construction phase where
appropriate.
2.3.28
No adverse cumulative air quality impacts were
predicted at the air sensitive areas for the operation phase in the WDIICFS EIA
Report, after considering the background pollutant levels within and adjacent
to WDII, vehicle emissions from open road networks, tunnel portal and
ventilation building emissions from the CWB, tunnel portal emissions from the
Cross Harbour Tunnel, and portal emissions from existing underpasses and
planned deckovers. No mitigation
measures were required under the WDIICFS EIA Report.
2.3.29
Air
quality impacts are updated in the
WDII&CWB EIA Report, which also considers on the background pollutant
levels, vehicle emissions from open road networks, tunnel portal and
ventilation building emissions from CWB, tunnel portal emissions from existing
tunnels, underpasses and planned deckovers with updated and latest available
data in assessing the cumulative air quality impacts. Findings of the air quality assessment
are given in Section 3 of this report.
2.3.30
WDII construction noise impacts were predicted taking
into account other concurrent projects including the CRIII and CWB&IECL
projects and the Causeway Bay Flyover project in the WDIICFS EIA Report. As the Causeway Bay Flyover project has
already been completed, the current WDII&CWB EIA Report has not included
the Causeway Bay Flyover project as a concurrent project.
2.3.31
It was given in the WDIICFS EIA Report that, with the
use of silenced equipment and movable barriers for WDII construction tasks and
implementation of the noise mitigation measures proposed in the CRIII and
CWB&IECL EIA Reports, the noise levels at all residential noise sensitive
receivers (NSRs) would comply with EIAO-TM construction noise criteria during
normal daytime working hours, with mitigated noise levels being in the range of
60 to 75 dB(A). Some noise
exceedences of 4 to 7 dB(A) were still predicted at the Performing Art Centre
and at the HKCEC Extension.
However, these NSRs are equipped with central air-conditioning systems
and good noise insulation facilities, and they do not rely on openable windows
for ventilation. No adverse noise
impacts were therefore expected for the indoor environments of these NSRs.
2.3.32
An
indicative assessment was undertaken in the WDIICFS EIA Report for possible
construction activities during restricted hours (1900 to 2300) associated with
the reclamation works of the Project.
With the reduction of plant numbers, adoption of quiet plant and
reduction of on-time percentage for some equipment, the predicted noise levels
at all representative residential NSRs would comply with the construction noise
criterion of 65 dB(A). Noise
exceedences of the 65 dB(A) criterion at HKCEC were still predicted at certain
periods, for plant working close to the HKCEC Extension. The results of the construction noise
impact assessment for restricted hours (1900 to 2300) were for indicative
purposes; the Noise Control Authority will process any CNP application, based
on the NCO and the relevant technical memoranda in addition to considering the
contemporary situations / conditions.
2.3.33
The
construction noise impact assessment has been updated for the revised
scheme. The current
WDII&CWB EIA follows similar principles adopted in the WDIICFS EIA Report
and reduction of plant numbers, adoption of quiet plant and reduction of on-time
percentage for some equipment are also adopted in the WDII&CWB EIA. Findings of the updated construction
noise impact assessment for the WDII&CWB EIA are given in Section 4 of this
report.
2.3.34
In
the WDIICFS EIA Report, the potential road traffic noise impacts were assessed
for the worst-case traffic flows in 2027.
No adverse traffic noise impacts were expected and no operational
mitigation measures were proposed for the WDII roads. No adverse impact from helicopter noise
and fixed noise sources including ventilation shaft noise from the CWB
ventilation buildings were anticipated at the existing and planned NSRs.
2.3.35
In
the WDII&CWB EIA Report, the potential road traffic noise impacts are
assessed for the worst-case traffic flows in 2031 in accordance with the updated programme for the WDII and CWB projects. The operation noise impact assessment
and the recommended operation noise mitigation measures for the WDII&CWB
EIA are given in Section 4 of this report, including the considerations on the
helicopter noise and ventilation shaft noise from the CWB ventilation
buildings.
2.3.36
The
water quality impacts during the reclamation of WDII were quantitatively
assessed by numerical modelling in the WDIICFS EIA Report. Suspended sediment was identified as the
most significant water quality parameter during the reclamation. The worst-case scenarios during
reclamation, taking into account the anticipated reclamation stages and
possible overlapping dredging and filling activities, were assessed. The assessment also took into account
the cumulative effects that arise from the adjacent CRIII reclamation and other
concurrent reclamation works in the harbour. It was predicted that potential water
quality impacts could occur at seawater intakes along the Central and Wan Chai
shorelines and in the CBTS, with a maximum concentration of suspended solids
(SS) at the surface layer up to 263 mg/l.
However, the water quality impacts at the seawater intakes can be
effectively minimised with the implementation of proposed mitigation measures,
which include silt curtains around the dredging operations, silt screens at the
intakes and bulk filling behind constructed seawalls. Maximum surface SS levels at the
seawater intakes would be less than 30 mg/l after the implementation of these
measures and there would be no residual adverse water quality impacts due to
the WDII reclamation and due to the cumulative effects from other concurrent
reclamation activities.
2.3.37
Suspended sediment is still identified as the most
significant water quality parameter during the reclamation in the WDII&CWB
EIA Report and numerical modelling is also adopted for the quantitative
assessment for water quality impacts during reclamation of WDII. Similar mitigation measures, including
silt curtains around the dredging operations and silt screens at the intakes, will
be applicable for the WDII&CWB EIA Report. The construction phase water quality
assessment based on the updated reclamation sequence and concurrent reclamation
works at the harbour for the WDII&CWB EIA is given in Section 5 of this
report.
2.3.38
Water
quality impacts from land-based construction, including road works, waterfront
facilities and public utilities, are associated with the surface runoff,
effluent discharge from the site and sewage from on-site construction workers. Impacts can be controlled to comply with
statutory standards by implementing mitigation measures such as on-site
drainage and sediment traps to control run-off. No unacceptable impact on land-based
water quality impact was anticipated in the WDIICFS EIA Report. The water quality impacts from
land-based construction would be similar for both the WDIICFS EIA Report and
the WDII&CWB EIA Report.
Findings of the WDII&CWB EIA Report shall refer to Section 5 of this
report.
2.3.39
An
assessment of the hydrodynamic impact due to the WDII reclamation, including
the adjacent CRIII reclamation, was undertaken for the coastline configuration
in the WDIICFS EIA Report. Potential impacts to tidal flows were assessed by
comparing the baseline and operation phase conditions. It was concluded in the WDIICFS EIA
Report that the WDII reclamation will have minimal impact on the hydrodynamic
regime in the study area. With the
extent of reclamation substantially reduced, the impact on hydrodynamic regime
for the WDII&CWB EIA would be minimal as compared to WDIICFS EIA. Assessment of the hydrodynamic impact
due to the latest coastline configuration is included in the WDII&CWB EIA
Report and the findings are presented in Section 5 of this report.
2.3.40
An
assessment of the water quality impacts during the operation of WDII was also
undertaken in the WDIICFS EIA Report.
Comparison between the baseline and operational water quality modelling
results suggested that the levels of pollutants near Wan Chai and the neighbouring
areas were similar under both baseline and operational scenarios. No unacceptable impacts associated with
the operation of WDII upon the water quality in Victoria Harbour were envisaged. Operation
phase mitigation measures were not considered necessary in the WDII CFS EIA
Report. Similar findings would be
expected for the revised scheme, nevertheless, assessment of water quality
impacts during the operation of WDII based on the latest discharge locations
and shoreline configuration for both baseline and operational scenarios are
undertaken in the WDII&CWB EIA Report and presented in Section 5 of this
report.
2.3.41
In
the WDIICFS EIA Report, the total volume of dredged sediment for the WDII
reclamation was estimated to be approximately 0.99 Mm3 and some 0.6 Mm3 of the marine sediments
would be classified as Category H.
With the implementation of mitigation measures in accordance with the
requirements of WBTC No. 3/2000, and disposal to the contaminated mud pits, no
residual adverse impact was predicted.
In the CBTS, Category H sediments with high pollutant concentrations
were identified. Containment of the
contaminated sediments in geosynthetic containers before disposal at the
contaminated mud pits was proposed to minimise release of material to the marine
environment. Field trials were
recommended to establish the optimum handling method for this approach.
2.3.42
For
the revised scheme, the total volume of dredged sediment, including the
quantities of Category H contaminated sediments, is updated and presented in
Section 6 of this report. The use
of geosynthetic containers for containment of the contaminated sediments before
disposal at the contaminated mud pits are also proposed in the WDII&CWB EIA
Report. The field trials as
recommended in the WDIICFS EIA Report have already been completed and the findings
are incorporated in Section 6 of the WDII&CWB EIA Report.
2.3.43
According
to the WDIICFS EIA Report, wastes generated by construction activities would
include construction and demolition (C&D) materials (including excavated material),
general refuse and chemical waste.
Provided that these identified waste arisings would be handled,
transported and disposed of using approved methods and that the recommended
good site practices as identified in the WDIICFS EIA Report were strictly
followed, adverse environmental impacts were not anticipated. The C&D material should be sorted
on-site into inert C&D material (ie public fill), for reuse in the
reclamation, and C&D waste for recycling or disposal. The type of waste generated from the
revised WDII and CWB projects would be similar to those of the WDIICFS but the
quantities are updated with the increase in tunnel length. The updated assessment on waste
management for the WDII&CWB EIA is given in Section 6 of this report.
2.3.44
The
land contamination assessment in the WDIICFS EIA Report included a review of
site history and existing environmental information, and a preliminary site
inspection. Two possible
contaminated land sites were identified: the A. King Marine shipyard in the
CBTS and the boatyard area of the RHKYC.
Potential contaminants arising from shipyard operations and the yacht
club were identified, however, based on available information, the potential
for land contamination in these areas was not considered to be insurmountable. It was proposed in the WDIICFS EIA
Report that site investigation should be conducted prior to the commencement of
site clearance / construction works.
2.3.45
For the new Trunk Road layout now proposed, the
boatyard area of RHKYC will not be affected and it is no longer identified as a
possible contaminated site in the WDII&CWB EIA Report. The site investigation at A King
Shipyard as proposed in the WDIICFS EIA Report has been carried out and the
findings are included in the WDII&CWB EIA Report. The updated land contamination
assessment for the WDII&CWB EIA is given in Section 7 of this report.
2.3.46
The
ecological assessment in the WDIICFS EIA Report indicated that the marine
ecological resources within the WDII area were considered to be of low
ecological value. The dredging and
reclamation works would result in the permanent loss of approximately 28.5
hectares of soft bottom benthic habitat.
Approximately 1,110m of rock armoured sloping seawall
and 440m of
sloping seawall (with granite facing) would be permanently lost due to
reclamation or removal of existing breakwaters. Approximately 2,800m of existing vertical seawall would also be lost
during the reclamation, but some 1.5 km
of new caisson wave energy absorbing seawall and 1.3 km of new blockwork seawall would be
constructed. These seawalls were
expected to provide habitat of similar ecological value to that of the existing
blockwork seawalls that constitutes the main part of the reclaimed intertidal
habitat. Since the benthic
community and intertidal community in the study area are of low ecological
value, only minor impacts were anticipated from the reclamation works in the
WDIICFS EIA Report.
2.3.47
With the reduction in extent of reclamation, the
permanent loss of soft bottom benthic habitat and artificial intertidal habitat
under the WDII&CWB EIA are expected to be less than the WDIICFS EIA. Nevertheless, the marine
ecological assessment has been updated under the WDII&CWB EIA and is given
in Section 9 of this report.
2.3.48
In
the WDIICFS EIA Report, organically enriched marine bottom sediment was planned
to be left in-situ at the WDII reclamation within the western and eastern
corners of the CBTS. As methane gas
could be generated under anaerobic conditions, there was a potential for this
gas to be released either during construction or after development of the
reclaimed area. Assessment on
impact of biogas emissions was included in the WDIICFS EIA Report, which
concluded that with the incorporation of the recommended gas protection
measures in the design of the developments and precautionary measures during
construction activities, the risk to people and property due to biogas
emissions from the WDII reclamation is considered to be low. However, as a fully dredged approach is
adopted for the current project proposals and no more organically enriched
marine bottom sediment is planned to be left in-situ at the WDII reclamation,
assessment on biogas emissions is not included in the WDII&CWB EIA Report.
2.3.49
A
landscape and visual impact assessment (LVIA) was conducted in the WDIICFS EIA
Report to assess the impacts of the proposed developments within WDII, for both
the construction and operation phases, on the surrounding area. Landscape and visual mitigation measures
would be achieved principally through the realisation of a Master Landscape
Plan encompassing the following objectives:
·
the
establishment of a network of open spaces providing for a range of functions
including pedestrian circulation and as a venue for community events;
·
the
creation of major landscape spaces forming pedestrian arteries linking the
waterfront with existing open spaces, proposed and existing adjacent
developments and other areas of the city;
·
the
establishment of an integrated, pedestrian oriented streetscape which will
enhance pedestrian movement, integrate the proposed and existing developments
within an overall landscape framework and generally improve the quality of the public environment;
·
the
provision of green buffer areas to mitigate negative environmental conditions
associated with transport corridors, especially for the proposed IECL;
·
the
development of an integrated, fully co-ordinated design, incorporating all
foreseeable functional requirements such as utilities, drainage reserves, and
pumping stations;
·
the
creation of a high quality Waterfront Park which will reflect and integrate with that proposed for the Central
Reclamation development;
·
the
provision of open space linkage between the Central Reclamation and HKCEC in
the west, the RHKYC, Victoria Park and stretching to North Point to the east.
In the WDII&CWB EIA Report, the above objectives for
landscape and visual mitigation have been considered in the development of the
Concept Plan, RODP and Master Landscape Plan for the new project proposals.
2.3.50 As mentioned
in the WDIICFS EIA Report, the ability to create a world-class
harbour frontage, in respect of visual and landscape impacts, was somewhat
constrained in the area adjacent to the IECL. This was due to the dominating visual
presence of the IECL running through the reclaimed CBTS and also because a
large landscape area would lie under the IECL at the newly formed land over the
CBTS. However, in the WDII&CWB
EIA Report, the Trunk Road will be below the existing seabed of the CBTS and
the existing CBTS will be retained.
There is no IECL running through the CBTS. The previous findings of the visual and
landscape impacts of the IECL through the CBTS no longer apply; these are
updated in the WDII&CWB EIA Report.
2.3.51
During
the construction phase, the potentially most significant landscape and visual
impacts identified in the WDIICFS EIA Report were:
·
Substantial
landscape impacts on street tree planting in Wan Chai North and on the
landscape character of the streets and open spaces in Wan Chai North and Causeway Bay. The HKCEC promenade, Convention Avenue,
RHKYC and CBTS areas would be particularly affected. The total number of trees affected was
in the order of 420.
·
Substantial
visual impacts on the majority of buildings in Wan Chai, Wan Chai North and Causeway Bay that have a harbour outlook.
The RHKYC and Police Officers' Club would be surrounded by the various
developments, which would create a large magnitude of change in views during
construction. Substantial impacts
on some of the public open spaces in Wan Chai North and Causeway Bay. The areas of permanent and temporary
loss of the public open spaces were approximately 1.05 ha and 0.2 ha respectively.
2.3.52
For
the operation phase, the WDIICFS EIA found that, after all mitigation measures
have been implemented and have matured over 10 years, there would still be some
residual adverse landscape and visual impacts, the most significant impacts
being:
·
Substantial
visual impacts on the buildings in Wan Chai North which would have their
harbour views blocked by the proposed CDA development, on buildings along
Gloucester Road in Causeway Bay which would have their harbour views partially
obscured by the proposed hotel / commercial development and which would also
have clear views of the IECL, and on the Police Officers' Club which would be
visually dominated by the IECL and the proposed hotel / commercial development.
2.3.53 However,
for the new WDII and CWB project proposals, the Trunk Road will be in tunnel
through the CBTS and no new major developments are proposed. Landscape and visual impacts are
therefore substantially reduced.
The revised LVIA for the new scheme is presented in Section 10 of this
report.
Review of
Previously Approved CRIII EIA Report
2.3.54 Apart from
the two EIA Reports for the WDIICFS and CWB&IECL mentioned above, there are
also previous EIAO submissions, either associated with projects within the
current Project boundary or that contain information relevant to the previous
or current development schemes for the Project. The previously approved EIA for CRIII –
Studies, Site Investigation, Design and Construction (Application No.
EIA-055/2001) is one of the identified relevant EIA reports.
2.3.55 The
previously approved CRIII EIA Report includes four Schedule 2 DPs with
Environmental Permit (EP-122/2001) issued prior to commencement of
construction. The relevant Schedule
2 DP is for the construction of the CWB within the CRIII area. As the
original scheme for the CWB within CRIII has not changed, the EIA assessments
of the approved CRIII EIA Report and the EP issued for the construction of the
CWB within the CRIII area remain valid.
2.3.56 Some of
the CRIII works will take place concurrently with the WDII and CWB works. With respect to the assessment of
environmental impacts, the key indicators of air and noise will be influenced
by the cumulative effects of the overlapping construction works. The concurrent activities and the
cumulative environmental impacts have been assessed in the current WDII&CWB
EIA Report.
2.3.57 The
concurrent dusty construction activities undertaken within 500m from the boundary of the WDII area and within
the CRIII area are included in the air quality impact assessment for the
WDII&CWB EIA and summarised in Section 3 of this report.
2.3.58 The
concurrent construction activities in CRIII that have been included in the
noise impact assessment for the WDII&CWB EIA are given in Section 4.5 of
this report.
2.3.59 All the
marine dredging activities for CRIII will be completed before the construction
of WDII. No concurrent dredging activities
for CRIII that will affect the water quality impact assessment of the
WDII&CWB EIA are identified.
2.3.60 With
regard to solid waste management, provided that the recommendations put forward
in the previously approved CRIII EIA Report relevant to the construction of the
CWB tunnel within CRIII are conscientiously acted upon, the storage, handling,
collection, transport, and disposal of wastes arising from the construction of
the CWB tunnel within CRIII will be in full compliance with the regulatory requirements.
2.3.61 The CWB
tunnel will be entirely below ground for the section within CRIII. The CRIII EIA found that both the
landscape and visual impacts within CRIII are acceptable with mitigation
measures as described in category (c) of Annex 10 of the EIA-TM. The key mitigation measures recommended
in the approved CRIII EIA Report are mainly for the open spaces and above
ground structures, which will be implemented under the CRIII project. The findings and recommendations of the
approved CRIII EIA Report in respect of landscape and visual impacts associated
with the CWB within CRIII are still valid.
Review of
Previously Approved HKCEC Atrium Link Extension EIA Report
2.3.62 The
previously approved HKCEC Atrium Link Extension (ALE) EIA Report (Application
No. EIA-120/2006) is also relevant to the current WDII&CWB EIA.
2.3.63 Some of
the ALE works will take place concurrently with the WDII and CWB works. With respect to the assessment of
environmental impacts, it is the key indicator of noise that will be influenced
by the cumulative effects of the overlapping construction works. The concurrent activities and the
cumulative environmental impacts have been assessed in the current WDII&CWB
EIA Report.
2.3.64 The
concurrent construction activities under the ALE project that have been
included in the noise impact assessment for the WDII&CWB EIA are given in
Section 4 of this report.
2.3.65 During the
operation phase of the WDII&CWB projects, the ALE will be in
operation. The impact assessment
for the operation phase of the WDII and CWB projects has taken into
consideration the completed ALE.
2.4
Project Requirements, Scope and
Benefits
Project Requirements
2.4.1
The
basis of the WDII project and the core transport infrastructure for which the
project provides is the Trunk Road.
The Trunk Road is defined from the connection with the existing Rumsey
Street Flyover in Central, through to a connection with the existing IEC to the
east of the Causeway Bay Typhoon Shelter.
At the Rumsey Street Flyover connection, a Central Interchange will
provide connections into the Central area, and then the Trunk Road will drop
down into tunnel and run along the Central shoreline, through CRIII, to the
WDII project area. In WDII, the
Trunk Road will continue in tunnel until it needs to rise onto elevated flyover
structure to connect with the elevated IEC. The section of the Trunk Road that runs
in tunnel through CRIII and WDII is also known as the CWB, whilst the section
of the Trunk Road on flyover, for the connection with the IEC, is also known as
the IECL.
2.4.2
The
Trunk Road will form an east-west strategic route through Central and Wan
Chai. The Trunk Road is an
essential element of Government’s strategic transport planning for Hong Kong;
it is the “missing link” in the strategic highway running along the northern
part of Hong Kong Island. The Trunk Road is
required to provide relief to the existing main east-west route (Connaught Road
Central – Harcourt Road
– Gloucester Road).
2.4.3
The
Trunk Road was originally proposed under the Central and Wanchai Reclamation
Feasibility Study, completed in 1989, where its feasibility was
established. The need for the Trunk
Road was reaffirmed in the WDIICFS, completed in 2001, which demonstrated an
urgent need for the link to be put in place in order to relieve the existing
and growing congestion along the east-west corridor of Hong Kong Island
North. A number of strategic
traffic studies have also confirmed the need to improve the flow of the
east-west traffic through Central and Wan Chai, including the Long Term Road
Study completed in 1968 and the First, Second and Third Comprehensive Transport
Studies (CTS) completed in 1976, 1989 and 1999 respectively. A recent rerun of the CTS-3 transport
model also confirmed the need for the CWB despite changes in land use planning
assumptions and population projections.
2.4.4
Following
the 9 January 2004 CFA ruling on compliance with the PHO, the compelling and
present need for the Trunk Road to meet the transport needs of the community within
a reasonable and definite planning time frame, and to meet the social and
economic needs of the community, was established under the CRIII project, and
is presented in “A Review of Central Reclamation Phase III by applying the
Court of Final Appeal’s “Overriding Public Need Test” April 2004”.
2.4.5
Under
the WDII project, the compelling and present need for the Trunk Road has also
been confirmed. Reference can be
made to the “Report on Cogent and Convincing Materials to Demonstrate
Compliance with the Overriding Public Need Test” (the CCM Report).
The CCM Report can be viewed at the website:
http://www.devb.gov.hk/reclamation/en/basic/review_report/cogent_report/index.html.
2.4.6
Apart
from providing land for key transport infrastructure and reprovisioned
waterfront facilities, the Project can also create a coherent pattern of land
use and provide for the development of an appropriate waterfront ‘edge’ to the
existing urban area.
Project Scope
2.4.7
The
scope of the Project comprises:
(i)
Land
formation for key transport infrastructure and facilities, including the Trunk
Road (i.e. CWB) and the associated slip roads for connection to the Trunk Road
and for through traffic from Central to Wan Chai and Causeway Bay. The land formed for the above transport
infrastructure will provide opportunities for the development of an attractive
waterfront promenade for the enjoyment of the public.
(ii) Reprovisioning
/ protection of the existing facilities and structures affected by the land
formation works.
(iii) Extension,
modification, reprovisioning or protection of existing storm water drainage
outfalls, sewerage outfalls and watermains affected by the revised land use and
land formation works.
(iv) Upgrading
of hinterland storm water drainage system and sewerage system, which would be
rendered insufficient by the land formation works.
(v) Provision
of the ground level roads, flyovers, footbridges, necessary transport
facilities and the associated utility services.
(vi) Construction
of the new waterfront promenade, landscape works and the associated utility
services.
(vii) The
Trunk Road (i.e. CWB) within the study area and the associated slip roads for
connection to the Trunk Road.
Project Benefits
2.4.8
The
Project provides essential land for the construction of key transport
infrastructure including the Trunk Road and the NIL and SCL. The road and rail routes are required to
relieve congestion on the strategic east-west routes through Central, Wan Chai
and Causeway Bay and on the public transport system, and their implementation is a core
element of Government's transport planning strategy.
2.4.9
The
Project also provides opportunity to create an attractive waterfront for the
enjoyment of the public. At
present, large parts of the Wan Chai, Causeway Bay and North Point waterfront are inaccessible to the public or are
difficult to access. The land
formed through this Project will be used to regenerate the waterfront into an
attractive public resource that could be used for a wide range of recreational
and tourism-related uses and functions, with easy access from the urban
hinterland. In so doing, the
waterfront will become, as it should, an integral element of the public asset
currently provided by the harbour.
2.4.10
Environmental
benefits of the project have been discussed in paragraph 2.4.18 below and are summarised in
Section 15.2 of this EIA Report.
Consequences of Not Proceeding
with the Project
(i) Not
able to meet the need for the Trunk Road
2.4.11
The
need to provide a strategic trunk road along the northern shore of Hong Kong Island has long been identified.
The Trunk Road is the missing link required to complete this strategic
route. The Trunk Road is needed to
divert through traffic away from the Central Business District and from the
existing east-west traffic corridor of Connaught Road Central – Harcourt Road – Gloucester Road. It is also needed to cater for the
anticipated natural growth of traffic and to alleviate the already existing
congestion on the road networks.
Without the Trunk Road, there will not be sufficient capacity to serve
the heavy demands at both the strategic and local levels.
2.4.12
The
existing east-west corridor (Connaught Road Central – Harcourt Road – Gloucester Road)
serving the CBD on Hong Kong
Island is already
operating beyond its capacity, as can be observed on site. Previous and recent strategic transport
studies have predicted further increase in traffic demand along the east-west
corridor, and confirmed the need for a parallel east-west Trunk Road to avoid
more extensive and frequent traffic congestion, and even gridlock, on the road
network.
2.4.13
A
district traffic study has confirmed that a dual 3-lane Trunk Road (or
Central-Wan Chai Bypass), together with intermediate slip roads, is required to
divert traffic away from the existing east-west corridor and to provide
adequate relief to the corridor and the local road network.
2.4.14
Traffic
management and fiscal measures are already in place to maximise the capacity of
the existing road network and suppress traffic demand. Further measures including ERP have also
been considered. However, all these
existing and proposed measures, alone, cannot resolve the traffic congestion
problem along the east-west corridor.
In other words, the Trunk Road is essential, and ERP can complement the
Trunk Road but cannot replace it.
2.4.15
The
need for the Trunk Road has also been confirmed by the Expert Panel on
Sustainable Transport Planning and Central-Wan Chai Bypass, comprising leading
independent local and overseas transport planning experts. The Expert Panel supports the construction
of the CWB to improve the reliability of the road network and to enhance
multi-modal public transportation in the Connaught Road Central – Harcourt Road – Gloucester Road
corridor. The Expert Panel agrees
that the inability of the present infrastructure capacity to cope with the
present and future travel demand would persist even if development in the
Central reclamation area were stopped and territory-wide car ownership held
unchanged from now until 2016, and therefore recommends the construction of the
Trunk Road as a medium term solution to tackle the problem of deteriorating
traffic congestion in the Central and Wan Chai area. The Expert Panel further supports the
provision of the planned slip roads at the HKCEC area and at the Victoria Park Road
/ Gloucester Road
/ Hing Fat Street
passageway, to magnify the benefits of the CWB. The Expert Panel also recognises the
need for Road P2 both in the longer term and as an important ad interim measure
in addressing traffic congestion in the Central reclamation area even before
the CWB is implemented.
(ii) NIL and SCL
2.4.16
Land
formed under the Project, in addition to providing for the construction of the
Trunk Road, also provides for the construction of the NIL and the SCL. Should the Project not proceed, implementation
of these rail routes will be severely constrained. This will have consequential adverse
impacts on the planning and provision of public transport infrastructure.
(iii) No improvement of the waterfront
2.4.17
Should
the Trunk Road not be implemented the requirement for land formation will fall
away and opportunities to improve the existing waterfront would be
limited. The following scenarios
are likely:
·
no
new land will be available to upgrade and improve the waterfront;
·
it
will be difficult to realise the Town Planning Board's objectives stipulated in
the Vision and Goals for Victoria Harbour
to make the harbour attractive, vibrant, accessible and symbolic of Hong Kong;
·
it
will also be difficult to achieve the harbour-planning principles established
by the HEC, including, amongst others, sustainable development, proactive
harbour enhancement, vibrant harbour, accessible harbour and public enjoyment.
2.4.18
In
environmental terms, the likely conditions in the absence of the project are:
·
The
existing odour nuisance at the CBTS would persist and no improvement of the
situation would be expected.
The Project will provide opportunities to remove the potential sources
of odour nuisance within the CBTS so as to alleviate this existing environmental
problem as well as to provide an acceptable environment for the future land
uses within the project area.
·
In
the absence of project, similar air quality conditions along the northshore
areas of Wan Chai, Causeway Bay and North Point as currently exist would be expected to continue. There would be no opportunity to improve
air quality condition by diverting traffic underground. With the project, air quality at the east
tunnel portal area of the proposed Trunk Road would be enhanced by the
introduction of an electrostatic precipitator system into the tunnel ventilation exhaust system and zero portal emission
design of the East Tunnel Portal.
·
In
the absence of the project, the noise environment of the project area would be
increased due to the natural growth of traffic. In the presence of the project,
it would help lessen the traffic burden on Gloucester Road by diverting traffic to the proposed Trunk Road tunnel. There would be
an improvement of the noise environment alongside Gloucester Road. Besides, the project
would provide an opportunity to alleviate the noise impact at noise sensitive
receivers along IEC at North Point area by installing the proposed landscaped
deck at the east tunnel portal area of the Trunk Road and direct noise
mitigation measures on the reconstructed IEC. In this regard, it is anticipated
that the future noise environment would be improved in the presence of the
project.
·
No
improvement of the existing landscape and visual conditions of the waterfront
would be expected. With the implementation of the Project, there will be
substantial to moderate positive landscape and visual impact along the new
waterfront as the landscape and visual amenity are generally enhanced and
strengthened.
·
Water
quality at Victoria Harbour would be similar for both the situations with and without the Project.
2.5
Consideration of Alternatives and
Development of Preferred Option
Introduction
2.5.1
Having
established the need for the Trunk Road, any reasonable alternative to
reclamation that may meet this overriding need must be determined. In other words, can an alternative
alignment or form of construction for the Trunk Road be adopted that will
obviate the need for reclamation?
If there is a feasible “no reclamation” option, then it should be
pursued. Only if the need for
reclamation can be demonstrated to be necessary will scenarios involving
minimum reclamation be contemplated.
2.5.2
A
detailed examination of Trunk Road needs and constraints, including an
exhaustive investigation into the need for reclamation for the Trunk Road
construction and of alternative schemes that might do away with reclamation or,
at least, minimise reclamation, has been carried out. A “Report on Trunk Road Alignments and
Harbour-front Enhancement, April 2006” was submitted to the HEC Sub-committee on WDII Review, which set out
the findings of these investigations and the conclusions regarding the need for
reclamation and the minimum extent of reclamation. A copy of the report is given in Annex G
of the CCM Report which can be
viewed on the website at:
http://www.harbourfront.org.hk/eng/content_page/reportTRA.html?s=1.
Alternative Trunk Road Alignments
and Construction Methods
Alignment
Constraints
2.5.3
In
assessing the alignment of the Trunk Road through the WDII project area, the following
constraints have to be considered:
·
at the western end, connection to the Trunk Road
tunnel to be constructed under the CRIII project is required;
·
at the eastern end, the Trunk Road needs to connect
to the existing elevated IEC flyover structure;
·
provision of slip road connections in Wan Chai
North and at Causeway Bay;
·
avoid affecting the MTR Tsuen Wan Line tunnel
structure;
·
avoid affecting the Cross Harbour Tunnel (CHT) or
conflicting with the rock anchors at the CHT tunnel portal;
·
allow for proposed rail infrastructure: SCL and
NIL; and
·
avoid affecting existing services infrastructure
such as electricity sub-stations and sewage treatment plants and the basement
or piled foundations of existing developments along Wan Chai North, such as the
HKCEC Extension, Grand Hyatt Hotel, Wan Chai Towers, Central Plaza, Renaissance
Harbour View Hotel, Great Eagle Centre, Harbour Centre, China Resources
Building and Sun Hung Kai Centre, etc.
Trunk
Road Route Assessment
2.5.4
Alternative
routeings for the Trunk Road along offshore, inland and foreshore corridors
have been examined to determine practicable and feasible Trunk Road
alignments. Trunk Road alignments
are, however, constrained by existing development along the Wan Chai and Causeway Bay northshore area, existing cross harbour tunnels, proposed rail
infrastructure and essential services infrastructure.
2.5.5
Offshore
alignments are obstructed by the HKCEC Extension, will pose unacceptable risk
to the Cross Harbour Tunnel when tunnelling beneath it, and cannot provide the
necessary slip road connections.
Due primarily to the physical conflict with the HKCEC Extension, Trunk
Road offshore alignments are found to be not feasible.
2.5.6
Inland
alignments are obstructed by existing development in Wan Chai North, including
the HKCEC Phase I, Grand Hyatt Hotel, Great Eagle Centre and Sun Hung Kai
Centre. Trunk Road inland
alignments will also conflict with the proposed NIL and SCL rail
infrastructure, and existing road and services infrastructure. Due to these physical conflicts, Trunk
Road inland alignments are also found to be not feasible.
2.5.7
The
feasible Trunk Road routeing is along the foreshore of Wan Chai and Causeway Bay. After crossing over the
MTR Tsuen Wan line, the Trunk Road will run in shallow tunnel through the HKCEC
water channel and along the Wan Chai shoreline. Thereafter, the Trunk Road can pass
either below the Cross Harbour Tunnel portal in tunnel or over the top of the
Cross Harbour Tunnel portal as flyover, continuing as either tunnel or flyover
through the Causeway Bay Typhoon Shelter to a connection with the existing
elevated IEC to the east of the typhoon shelter.
2.5.8
However,
foreshore alignments do require reclamation for Trunk Road tunnel construction
at the western end of WDII where the Trunk Road tunnel crosses over the MTR
Tsuen Wan Line, and at the eastern end of WDII where the Trunk Road tunnel must
rise to ground level for the connection with the elevated IEC, at least.
Alternative Trunk Road Ideas
2.5.9
The
following alternative Trunk Road ideas, including suggestions received from the
public through the Envisioning Stage public engagement exercise, have been
examined to determine if they would constitute a feasible “no reclamation”
option, or result in an avoidance of reclamation:
·
deep
bored tunnel
·
double-decking
over Gloucester Road
·
full
flyover idea
·
total
offshore idea
·
shallow
water idea.
2.5.10
All
the alternative Trunk Road ideas that have been proposed to avoid reclamation
are found either to be not feasible, or result in an even greater area of reclamation
or affected area of the harbour than a foreshore alignment constructed as
cut-and-cover tunnel and flyover.
Alternative Construction Methods
2.5.11
For
the feasible Trunk Road routeing along the foreshore of Wan Chai and Causeway Bay, the Trunk road will start in tunnel at the connection with CRIII,
crossing over the MTR Tsuen Wan line, and staying in shallow tunnel through the
HKCEC water channel and along the Wan Chai shoreline. Thereafter, the Trunk Road can pass
either below the CHT portal in tunnel or over the top of the CHT portal as
flyover, continuing through the CBTS to a connection with the existing elevated
IEC to the east of the typhoon shelter.
2.5.12
For
tunnel options, cut-and-cover tunnel construction is considered to be a
technically feasible form of construction for implementation of the Trunk Road.
2.5.13
Whilst
there is broad support from the public for a tunnel option, especially where
this can incorporate suggested harbour-front enhancement ideas while at the
same time provide for the functional requirements of the Trunk Road, a flyover
option is also technically feasible.
This option has therefore also been considered, in particular as it
represents a scheme requiring a lesser area of new land formation. At issue, though, is which option, tunnel
or flyover, would comply with the PHO.
2.5.14
At-grade
Trunk Road options are not acceptable as they would require extensive
reclamation in the CBTS, thus not complying with the PHO, and the reclaimed
land would be used mainly for roads, leaving little opportunity for
harbour-front enhancement.
Comparison of Feasible Trunk Road
Options
Tunnel Option
2.5.15
For
the tunnel option for constructing the Trunk Road, three variations have been
considered. These three variations
are illustrated in Figures 2.1 to 2.3. Key features of the three variations are
briefly described as follows:
Variation 1
2.5.16
The
Trunk Road tunnel to be constructed under CRIII will be extended eastward to
pass underneath the existing rock anchors of the CHT portal structure, and
continues the tunnel to the east of the Causeway Bay Typhoon Shelter (CBTS) and
connects to the northern side of the existing IEC.
Variation 2
2.5.17
The
Trunk Road tunnel to be constructed under CRIII will be extended eastward to
pass underneath the CHT at a position to the south of that in Variation 1 to
avoid the rock anchor zone, and continues the tunnel to the east of the CBTS
and connects directly into the IEC by reconstructing a section of the existing
IEC. For widening the harbour-front
promenade adjoining the CBTS and provision of a wide landscaped deck for
extending Victoria Park to the harbour-front, the Victoria Park Road and associated connecting roads would be realigned inland.
Variation 3
2.5.18
Except
that the tunnel passes underneath the rock anchors of the CHT portal as in
Variation 1, other arrangements will be similar to Variation 2.
Flyover Option
2.5.19
Under
the flyover option, the tunnel to be constructed under CRIII will be extended
eastward, and will rise up onto an elevated road structure at the waterfront
opposite to the Wan Chai Sports Ground.
Figure 2.4 illustrates this option.
2.5.20
The
PHO requires the Harbour to be protected and preserved as a special public
asset and a natural heritage of Hong Kong people. Therefore, when examining options for
the Trunk Road, the one that may serve best to protect and preserve the Harbour
should be identified. For the
flyover option, the land formation by physical reclamation together with the
water areas of the Harbour affected by flyover structures should be taken into
account.
Comparison of Trunk Road Tunnel Variations
2.5.21
Table 2.1 provides a comparison between the Trunk Road Tunnel Variations 1, 2 and
3, in broad terms, in respect of key indicators: area of reclamation, impacts
to existing traffic, technical highway concerns and impacts to existing highway
structures, impacts to existing development, planning and land use
considerations, environmental concerns, time for construction and costs.
2.5.22
The
following major issues are highlighted as being of particular concern:
·
more
reclamation due to filling in of the corners of the Causeway Bay Typhoon
Shelter (south-east and south-west corners for Variation 2, south-east corner
for Variation 3);
·
major
road diversions and traffic impacts during construction (particularly for
Variations 2 and 3);
·
intrusion
into and demolition of Victoria Park for the construction of the realigned Victoria Park Road (both Variations 2 and 3);
·
need
for the reconstruction of major existing highway structures, including the IEC,
Gloucester Road Flyover and the newly constructed Causeway Bay Flyover (both
Variations 2 and 3);
·
demolition
of the Police Officers’ Club (Variation 2);
·
air
quality concern at the tunnel portal, due to close proximity of residential
units (all tunnel variations, but more so for Variations 2 and 3).
2.5.23
It
should be noted that the areas of reclamation given in Table 4.1 are the areas of permanent reclamation, and include a
notional allowance for reprovisioning requirements (for ferry pier, salt water
pumping station, cooling water pumping stations, etc) associated with each of
these tunnel variation options.
Table 2.1 Comparison
of Trunk Road Tunnel Variations
2.5.24
It
should also be noted that there will be a requirement for temporary works (including
temporary reclamation) to facilitate cut-and-cover tunnel construction and for
temporary traffic diversions. These
temporary works will be required in the ex-PCWA basin and in the Causeway Bay
Typhoon Shelter. In the Causeway
Bay Typhoon Shelter, the extent of the temporary works, for all three tunnel
variations, will be such that the existing moorings will need to be relocated
outside the typhoon shelter during the construction period.
2.5.25
As
can be seen, neither Tunnel Variation 2 nor 3 perform as well as the Trunk Road
Tunnel Variation 1. The major
drawbacks of Tunnel Variations 2 and 3 include additional reclamation for
filling in of the corners of the Causeway Bay Typhoon Shelter, major traffic
disruption, demolition of a large part of Victoria Park, demolition and then
reconstruction of major highway structures, and air quality concerns at the
tunnel portal area in North Point.
2.5.26
The
reclamation issue is particularly important in respect of the PHO. The Trunk Road Tunnel Variation 1
requires a lesser extent of reclamation than that associated with the Tunnel
Variations 2 and 3.
Comparison of Tunnel and Flyover Options
2.5.27
Table 2.2 provides a comparison between the tunnel and flyover options in broad terms,
in respect of key indicators: affected area of the Harbour, impacts to existing
traffic, technical highway concerns and impacts to existing highway structures,
planning and land use considerations, environmental concerns, time of
construction, and costs. Trunk Road
Tunnel Variation 1 is used as the basis of tunnel option comparison. The key issue that is of concern in
respect of the PHO is the area of the Harbour that will be affected by the
tunnel and flyover options.
2.5.28
The
PHO requires the Harbour to be protected and preserved as a special public
asset and a natural heritage of the Hong Kong people, and establishes a presumption against reclamation in the
Harbour. Notwithstanding that there
is an overriding need for reclamation for the project, it is essential to find
the option that will best serve to protect and preserve the Harbour, with the
minimum area of the Harbour affected by reclamation. In this regard, the area of the Harbour
affected by the alternative Trunk Road tunnel and flyover options is of
concern. The flyover structures
over water will impinge upon the water area of the Harbour and their visual
impacts do not promote the protection and preservation of the Harbour. Moreover, where the marine use of
existing water areas is restricted due to the presence of highway structures
and the like, these affected water areas may not be regarded as “protected” or
“preserved” for the purposes of the PHO.
2.5.29
Therefore,
when examining Trunk Road options, and especially when examining the flyover option,
the land formation by physical reclamation is taken into account together with
the water areas of the Harbour affected by flyover structures in order to
determine which option may serve best to protect and preserve the Harbour.
Table 2.2 Comparison
of Tunnel and Flyover Options
2.5.30
In
most respects, it is found that the Trunk Road tunnel option (Tunnel Variation 1)
performs better than the flyover option.
The tunnel option:
·
will
result in a lesser affected area of the Harbour;
·
will
cause less traffic disruption during construction;
·
will
not require any major reconstruction of existing highway structures;
·
will
have more opportunities for harbour-front enhancement and providing access to
the waterfront;
·
will
cause less extensive air and noise impacts (although air quality at the tunnel
portal will need to be carefully addressed);
·
will
have no significant visual impacts (the flyover, on the other hand, will have
significant visual impacts along the harbour-front).
2.5.31
Only
in respect of time for construction and costs can the flyover option be seen as
performing better than the tunnel option.
2.5.32
The
key issue of concern is which option would serve best to protect and preserve
the Harbour. In addressing this
concern, the area of the Harbour that is affected by the Trunk Road options
should be taken into account, including not only land formed by reclamation but
also the impingement of highway structures on the existing water areas and the
restricted use of water areas due to the presence of the highway structures (ie
the areas where the functionality of the Harbour is adversely affected). In addition, the visual aspects of the
flyover option (viewed in terms of “preserving the Harbour”) should be
considered. In these respects, the
Trunk Road tunnel option is clearly the option that would serve best to protect
and preserve the Harbour.
Conclusion of the Comparison of Trunk Road Options
2.5.33
Comparing
the tunnel variations, Tunnel Variation 1 is found to require the least extent of reclamation, would cause the least
disruption to traffic during construction, has the least impacts to existing
highway infrastructure and the least impacts to Victoria Park. It should be noted that, when
considering Trunk Road variations having similar functional/traffic performance
(ie in meeting the overriding need), the CFA ruling on the PHO requires that
the one with the least amount of reclamation (in this case Tunnel Variation 1)
should be selected. Therefore, of
these tunnel variations, Trunk Road Tunnel Variation 1 is recommended,
in compliance with the requirements of the PHO.
2.5.34
Although
both capital and annual recurrent costs would be higher for the Tunnel Option
when compared with the Flyover Option, the Tunnel Option is recommended, in
compliance with the requirements of the PHO, primarily because the affected
area of the Harbour would be smaller and it would cause less visual impact than
the Flyover Option.
2.5.35
Trunk
Road Tunnel Variation 1 affects the minimum area of the Harbour and serves best
to protect and preserve the Harbour, among all the options that have been
assessed.
Public Views
2.5.36
The
first stage of the HER project, the Envisioning Stage, had as its purpose the
engagement of the community at an early stage to solicit their visions on the
need for and the form of Trunk Road as well as the types of harbour-front
developments they aspire for at Wan Chai, Causeway Bay and the adjoining
areas. Five public forums and two
community design charrettes were convened during May to July 2005, and opinion
surveys were carried out. These public
engagement activities were well received by the public, in particular by the
key stakeholders, as providing a platform for thorough exchange of views,
rational discussions and consensus building.
2.5.37
The
public’s views collected and findings of the Envisioning Stage are presented in
a Public Engagement Report, March 2006.
The report can be viewed on the HEC website at:
http://www.harbourfront.org.hk/eng/content_page/doc/engagement_report/Main_Report.pdf.
2.5.38
In
addition, discussions with the Town Planning Board, Legislative Council
(LegCo), District Councils and relevant statutory and advisory bodies have also
been held, as part of an on-going and continuous process of public engagement
for seeking consensus on the project proposals. In particular, the Town Planning Board,
relevant District Councils, LegCo Planning Lands and Works (PLW) Panel, Transport Advisory Committee and professional
institutions were further engaged from April to May 2006 on the findings
regarding alignments and construction forms for the Trunk Road and
harbour-front enhancement ideas.
2.5.39
The
general sentiment of the public, in respect of the Trunk Road ideas and
aspirations for harbour-front enhancement, expressed through the Envisioning
Stage consultation, includes:
·
a
preference for having the Trunk Road in tunnel;
·
generally,
an acceptance of the need for reclamation for shallow tunnel construction at
the HKCEC and along the Wan Chai shoreline;
·
but,
rather have tunnel options that do not result in reclamation in the Causeway
Bay Typhoon Shelter.
2.5.40
Overall,
Trunk Road Tunnel Variation 1 is seen as the best option in complying with the
PHO, and this Trunk Road option has clearly expressed support as the preferred
Trunk Road scheme.
Alternative
and Preferred Development Scheme
Preferred Trunk Road
Option
2.5.41
The preferred Trunk Road Option,
Trunk Road Tunnel Variation 1, provides for the necessary functional
requirements of the Trunk Road, in meeting the overriding need for the Trunk
Road, as well as resulting in the least affected area of the Harbour, in
conformance with the PHO.
2.5.42
A detailed examination of Trunk
Road needs and constraints, including an exhaustive investigation into the need
for reclamation for the Trunk Road construction and of alternative schemes that
might do away with reclamation or, at least, minimise reclamation, as well as
review of harbour-front enhancement suggestions put forward by the public and
the consolidation of these with the Trunk Road ideas, has been carried
out. These have been described
briefly above; more details on these assessments can be found in the “Report on
Trunk Road Alignments and Harbour-front Enhancement”. After due consideration of these
investigations, the HEC Sub-committee on WDII Review agreed at their meeting on
13 June 2006 to endorse Trunk Road Tunnel Variation 1 as the basis for proceeding
to the next stage of the WDII Review, the preparation of the Concept Plan.
Alternative Development Options
2.5.43
At
the Envisioning Stage, alternative development options with different land uses
for the harbour-front area have been proposed, such as proposals for lots of
water sports and tourism activities along the water front, proposals for an
informal waterfront along the study area as compared to a formal waterfront
along Central waterfront, proposals for berthing facilities for visiting vessels
with floating piers, openable footbridge link to the breakwater, urban beach at
Causeway Bay Typhoon Shelter, extending Victoria Park to the waterfront,
develop a lively harbour-front area at ex-PCWA, etc.
2.5.44
A
Consolidation Forum was convened on 12 November 2005 to share with the public
the comments and the different proposals received during the public enhancement
activities held from May to July 2005 for the Envisioning Stage, and to involve
the public in consolidating these views before proceeding with the preparation
of the Concept Plan for the development and enhancement of the harbour-front
area.
2.5.45
Details of the different development options proposed and the outcome of
the Consolidation Forum at the Envisioning Stage are given in the Public
Engagement Report, March 2006. The
report can be viewed on the HEC website at: http://www.harbourfront.org.hk/eng/
content_page/doc/engagement_report/Main_Report.pdf. The outcomes of the Envisioning Stage on
the development options and harbour-front enhancement then formed the basis of
the preparation of the Concept Plan in the Realization Stage. The consolidated ideas for the
preparation of Concept Plan are given below.
Concept Plan for the
Proposed Development Scheme
2.5.46
At the Envisioning Stage, there
were many common land use concepts proposed for the harbour-front to enhance
its vibrancy and attractiveness.
These are mainly reflected in the following activity nodes:
·
a
Cultural Node at the Hong Kong Convention and Exhibition Centre (HKCEC) area;
·
a
Green Leisure Zone at the Wan Chai waterfront; provision of water features has
also been proposed;
·
a
Water Sports/Activity Node at the ex-Public Cargo Working Area (PCWA) basin;
·
a
Heritage Zone at the CBTS;
·
a
Green Leisure Zone at the North Point waterfront.
2.5.47
These harbour-front suggestions
have been consolidated with the Trunk Road Tunnel Variation 1 option, together
with appropriate waterfront land use and landscape treatment. Harbour-front enhancement themes (arts,
culture and heritage, leisure and recreation) are used to reinforce identity
and provide variety and interest along the waterfront. The Concept Plan, as illustrated in Figure 2.5, that has been developed presents five “character precincts” as
follows:
·
an
“arts and culture precinct” to the west of the HKCEC, for arts and cultural
fairs, outdoor performance venues, an expo promenade, etc;
·
a
“water park precinct” along the Wan Chai shoreline, with landscaped
recreational areas incorporating water features and alfresco dining (outdoor
cafes, etc) to add vibrancy to the waterfront;
·
a
“water recreation precinct” at the ex-PCWA basin for water sports and
recreation, berthing for visiting ships or yachts, and with a water sports
centre and harbour education centre;
·
a
“heritage precinct” at the CBTS, preserving the existing typhoon shelter and
taking advantage of the floating Tin Hau Temple, Noonday Gun, etc, and with a
landscaped deck providing an extension of Victoria Park to the waterfront;
·
a
“leisure and recreation precinct” at the North Point new waterfront providing a
waterfront park, with landscaped recreational areas.
2.5.48
The Concept Plan, for the
development and enhancement of the harbour-front under the ambit of the WDII
Review, has been prepared for evaluation and consensus building by the public
in the Realization Stage. At a Consensus Building
Town Hall meeting on 16 December
2006, there was general agreement with the proposals put forward by the Concept
Plan, in respect of the Trunk Road proposal and the envisaged land uses. There was a consensus that the Concept
Plan would form the basis to proceed with the Detailed Planning Stage. The Recommended Outline Development Plan
(RODP) as illustrated in Figure 2.5a, which sets out detailed land use proposals, has been prepared
based on the Concept Plan. The RODP
can be viewed on the HEC website at:
http://www.harbourfront.org.hk/eng/content_page/doc/RODP.pdf.
2.5.49
The
public’s views collected on the Concept Plan and findings of the Realization
Stage are presented in a Public Engagement Report, April 2007. The report can be viewed on the HEC
website at: http://www.harbourfront.org.hk/eng/content_page/engage.html?s=2.
Alternative
Slip Road 8 Alignments
2.5.50
Slip
Road 8 will encroach into Victoria Park, affecting existing trees, recreational
facilities and open spaces.
Alternative alignments have been thoroughly examined with a view to
minimising these impacts. A
discussion paper that explains the considerations in examining the alignment of
Slip Road 8 and associated at-grade road layout has been prepared and is
attached in Appendix 2.4.
2.5.51
With
reference to this discussion paper, amongst the different options of Slip Road
8 alignments, Option 1B, which has no encroachment into the North Pavilion
Garden of Victoria Park, has been adopted.
The final layout of Slip Road 8 and associated at-grade roads is given
in Appendix 2.4.
2.5.52
Although
the existing facilities and trees at the North Pavilion
Garden will not be affected, Slip Road
8 will affect part of the bowling
green and the nursery compound at the north of the
Victoria Park. The reprovisioning
of affected facilities at Victoria Park is given in Annex A of Appendix 2.4.
Alternative Tunnel Portal Locations
2.5.53
The
location of tunnel portal is directly related to the alignment of the Trunk
Road, including both the vertical and horizontal alignments. The preferred Trunk Road Option, Trunk
Road Tunnel Variation 1, provides for the necessary functional requirements of
the Trunk Road, in meeting the overriding need for the Trunk Road, as well as
resulting in the least affected area of the Harbour, determined as described
above. The location of tunnel
portal follows the alignment for Trunk Road Tunnel Variation 1.
2.5.54
Alternative
tunnel locations have been included in the examination of alternative Trunk
Road alignments and forms of construction, for example a portal location at Wan
Chai North (flyover option) and further east along the North Point shoreline
(deep bored tunnel option).
Alternative tunnel portal locations, such as extending the tunnel and
portal eastward, would result in more affected area of the Harbour as compared
to the Trunk Road Tunnel Variation 1 and would not be in compliance with the
PHO. These alternative tunnel
portal locations are not recommended, nor are they permitted under the PHO.
2.5.55
Although
the location of the tunnel portal is driven by the Trunk Road scheme with the minimum
extent of reclamation and the least affected area of the Harbour, opportunity
has been explored to enhance the east tunnel portal area. A landscaped deck has
been proposed over the east tunnel portal area as shown in the Concept Plan (Figure 2.5) and the RODP (Figure 2.5a).
Alternative locations of Ventilation Buildings and Administration Building
2.5.56
The
location of the Central Ventilation
Building is determined by the available area along the Trunk Road tunnel box in
the Wan Chai north area, and is constrained by existing development and road
and railway reserves. The proposed
location at the west of the HKCEC and adjacent to the proposed landscaped deck
is off the waterfront area and would not compromise the area for a promenade
along the waterfront. The location
of the Central Ventilation Building
is shown in both the Concept Plan (Figure 2.5) and the RODP (Figure 2.5a). Alternative locations
such as the open spaces next to the HKAPA Extension or even the waterfront open
spaces at the east of HKCEC are not recommended as these locations would
sacrifice the use of areas for other beneficial land uses, in particular,
waterfront enhancement.
2.5.57
The
location of the East Ventilation Building is determined by the available area along
the Trunk Road tunnel box in the Causeway
Bay and North Point
areas. The proposed location at the
north of the FEHD Whitfield Depot, at the west end of the North Point
reclamation area, has been selected in order to increase the distance to the
nearby residents as far as practicable.
The building height has been minimised by placing some E&M equipment
in a basement. The overall height
of the building will be lower than the adjacent existing IEC elevated road.
2.5.58
During
the Realization Stage of the HER public engagement activities, there were
public views and suggestions on the location of East Ventilation Building proposed in the Concept Plan (Figure 2.5). The feasibility of
separating the exhaust vent shaft further away from the ventilation building has
consequently been considered. The
enhanced proposal with the vent shaft separated from the East Ventilation
Building and extended to
the tip of the eastern breakwater of the CBTS has been incorporated in the RODP
(Figure 2.5a). The air quality impact assessment
presented in Section 3 of this EIA Report indicates that the predicted air
quality at the air sensitive receivers (ASRs) would comply with the air quality
objectives (AQOs).
2.5.59
Alternative
locations of the vent shaft at the northern breakwater or the western
breakwater of the CBTS have also been explored. In view of the small contribution of the
exhaust from the vent shaft to the overall air quality, moving the vent shaft
at the eastern breakwater of CBTS to the northern breakwater or the western
breakwater of the CBTS would not result in any significant improvement of the
predicted air quality at ASRs in North Point. From the perspective of noise impact, no
difference is anticipated as the noise source is from the fixed plant of the
ventilation fans installed inside the East Ventilation Building, instead of the vent shaft.
The alternative locations will also have low energy efficiency as the
tunnel emission will be required to be extracted from the East Ventilation
Building to the northern
breakwater or western breakwater through a much longer air ventilation duct
than the one at the eastern breakwater.
In addition, the location of the vent shaft at the northern breakwater
or western breakwater is considered practically not feasible due to the
following technical constraints:
·
there
are two major infrastructures located on both sides of the western breakwater
namely the cross harbour gas main (about 30m west of the western breakwater) and immersed tube section of the CHT
(about 60m east of the western
breakwater). Any damage to these
two major infrastructures would cause profound disruption to the gas supply and
operation of the CHT. The construction
of the air ventilation duct and vertical shaft in close proximity to these two
infrastructures is extremely risky;
·
if
the exhaust vent is located at the western breakwater, the air duct will go
alongside the mainline tunnel of the CWB in order to reduce the construction
difficulty and potential risk of being damaged. As the mainline tunnel will run
below the CHT at around
-30mPD, there will be substantial level difference of about 30m between the air ventilation duct and the ground level at the western
breakwater. Only limited underground
space in the vicinity of the CHT south tunnel portal, Hung Hing Road and RHKYC is available for
the underground duct and the vertical air duct shaft. In order to bring the air ventilation
duct to the ground level and extend it to the western breakwater while keeping
it away from the CHT tunnel structure, the cross harbour gas main, the
clubhouse building of the RHKYC, which is a potential heritage building, and a
substantial portion of the RHKYC site will be affected;
·
the
alignment of the CHT is right underneath the western end of the northern
breakwater, any extension of the air ventilation duct to and construction of
the exhaust vent at this location will entail reconstruction of the breakwater
and impose great risk of damaging the immersed tunnel tube of CHT. Furthermore, the alignment of the
proposed Shatin to Central Link (SCL) will run at about 150m to the east of the CHT in order to achieve a safe clearance from CHT
during construction and operation of SCL in future. The required working space for
constructing the SCL will further impose restriction on locating the exhaust
vent within the western and middle portions of the northern breakwater. Therefore, the exhaust vent cannot be
practicably located at or near the western end and the middle portion of the
northern breakwater in view of the constraints imposed by the CHT and the
proposed SCL.
There is
no better practically feasible alternative location than the proposed location
of the vent shaft at the eastern breakwater of CBTS in terms of a balance of
engineering practicality, environmental benefits and visual compatibility to
the surrounding environment.
2.5.60
The height of the vent shaft is
required to facilitate air dispersion and discharge, To achieve dispersion of the vitiated
air from the tunnel to the open air, the recommended minimum height measured
from the bottom of the louvres is 12.5m to provide the required
stack height to prevent the tunnel exhaust from affecting future users of the
breakwater. Besides, to allow an
acceptable air discharge velocity and to achieve the required air flow rate, a
minimum louvre area of 94m2
should be provided and thus the height of the louvre is around 7.5m depending on the width of the
louvre. Given the ground level of
the eastern breakwater is around 5mPD, the height of the vent shaft is around
+25mPD for a building height of around 20m.
2.5.61
The
location of the Administration Building is selected at the least prominent location along the available
waterfront area. It is proposed at
a location underneath the elevated IEC, where other beneficial use is limited,
and adjacent to the tunnel portal area, where the tunnel operation and
maintenance vehicles can access the tunnel efficiently. The location of the Administration Building is shown in both the Concept
Plan (Figure 2.5) and the RODP (Figure 2.5a). Alternative locations along the waterfront would compromise the
opportunity for harbourfront enhancement and, hence, are not recommended.
Alternative Reclamation Options and
Shoreline Configurations
2.5.62
The
size of reclamation, and the corresponding shoreline configuration, is
determined based on the minimum extent of reclamation that is needed to meet
the essential engineering requirements for the construction of the Trunk
Road. It is the minimum reclamation
required to meet the overriding need for the Trunk Road. A step by step
approach is taken to ensure the reclamation is the minimum extent required. The first step is to confirm that there
is an overriding and present need for the Trunk Road. The next step is to identify any
“no-reclamation options”. If there
is no reasonable alternative to reclamation, the third step is to ensure that
the reclamation is restricted to only the minimum amount necessary to meet the
overriding public need.
2.5.63
The
compelling and present need for the Trunk Road has been confirmed and reference
can be made to the CCM Report. The
need for the Trunk Road is explained in Section 2 of the CCM Report and also
mentioned in paragraphs 2.4.10 to 2.4.17 above. The Trunk
Road is the “missing link” in the strategic road network of Hong Kong and will
provide the essential east-west linkage between Rumsey Street Flyover in Central
and the IEC in Causeway
Bay. The implementation of the Trunk Road
will relieve the existing congested east-west corridor of Hong Kong Island
North. The need for the Trunk Road
has been clearly established through traffic and transport studies. The Expert Panel has confirmed the need
for the Trunk Road and intermediate slip roads. The Expert Panel considers that the
Trunk Road is essential for improving the reliability of the road network. The findings of the traffic and
transport studies, and of the Expert Panel, demonstrate conclusively the
compelling and present need for the Trunk Road.
2.5.64
The
“no-reclamation” options are given in Section 3 of CCM Report. All possible alignments for the Trunk
Road, including suggestions from the public, have been examined, taking into
account land use and infrastructural constraints, with a view to determining if
there are any that do not require any reclamation for the Trunk Road
construction. It is found that the
feasible Trunk Road routeing is along the foreshore of Wan Chai and Causeway Bay. However, foreshore
alignments do require reclamation for Trunk Road tunnel construction at the
western end of WDII where the Trunk Road tunnel crosses over the MTR Tsuen Wan
Line, and at the eastern end of WDII where the Trunk Road tunnel must rise to
ground level for the connection with the elevated IEC, at least. There is no feasible “no-reclamation”
alignment for the Trunk Road, and at least some reclamation will be required
for the Trunk Road construction.
2.5.65
The
“Report on Trunk Road Alignments and Harbour-front Enhancement, April 2006” sets out the findings of the investigations on the alternative schemes
of the Trunk Road and the conclusions regarding the need for reclamation and
the minimum extent of reclamation.
Reference is made to Annex G of the CCM Report which can be viewed at the website:
http://www.harbourfront.org.hk/eng/content_page/reportTRA.html?s=1. As given in the above paragraphs 2.5.1
to 2.5.41, the preferred Trunk Road option, Trunk Road Tunnel Variation 1, has
been derived with a detailed examination of Trunk Road needs and constraints,
including an exhaustive investigation into the need for reclamation for the
Trunk Road construction and of alternative schemes that might do away with
reclamation or, at least, minimise reclamation. Trunk Road Tunnel Variation 1 affects
the minimum area of the Harbour and serves best to protect and preserve the
Harbour, among all the options that have been assessed. This option has clearly expressed
support as the preferred Trunk Road scheme, following extensive consultations
with various public, advisory and relevant statutory bodies.
2.5.66
Details
of the extent of reclamation, in respect of the engineering requirements for
the construction of the Trunk Road tunnel, reclamation and seawalls, are
presented in a “Minimum Reclamation Report”, a copy of which is appended at
Annex O of the CCM Report which can be viewed at the web site:
http://www.devb.gov.hk/reclamation/filemanager/en/content_19/annexO_e.pdf. Detailed examination of the
engineering requirements in respect of highway geometric design and
construction of the Trunk Road tunnel, reclamation and seawalls, and
reprovisioning requirements, has been carried out to accurately determine the
minimum extent of reclamation. In
total, an area of 12.7ha of reclamation (in addition to an
area of 0.4ha of
affected water area by flyover structures) is needed to meet essential
engineering requirements for construction of the Trunk Road. This is the minimum reclamation required
to meet the overriding public need for the Trunk Road.
2.5.67
With
the size of reclamation being minimised to the minimum extent to meet the
overriding need for the Trunk Road, the affected area of the harbour, the
foreshore and seabed is minimised, and the corresponding environmental impacts,
such as marine ecological and cultural heritage impacts, on the foreshore and
seabed are also minimised. Details
of the marine ecology and cultural heritage impact assessment for the proposed
scheme shall refer to the respective sections in this WDII&CWB EIA Report.
2.5.68
As
presented in the “Minimum Reclamation Report”, as appended at Annex O of the
CCM Report, the shoreline (ie the seawall copeline) is set at the minimum
separation from the Trunk Road tunnel and it follows the curvature of the Trunk
Road tunnel edge. Smooth curves
have been adopted at indented areas rather than sharp corners along the
shoreline, and a curved splay in the seawall is incorporated at the corner with
Expo Drive
East, where there is a drainage culvert.
This smoothing of the shoreline
will enhance flows and prevent accumulation of pollutants or floating refuse.
2.6
Construction Methods and Engineering Requirements
2.6.1
Alternative
construction methods have been considered in the CCM Report. Deep bored tunnel construction is
given in Section 3.4; immersed tube tunnel construction method is discussed in
Section 4.2; temporary reclamation for tunnel construction below seabed is
discussed in Annex O of the CCM Report.
Deep Bored Tunnel Construction
2.6.2
A
deep bored tunnel option for the Trunk Road has been examined with a view to
avoiding reclamation. The idea
being that a tunnel constructed by tunnel boring machine (TBM) at sufficient
depth below the surface would not require reclamation and can be constructed without
disturbing existing facilities and infrastructure.
2.6.3
However,
at the western end of WDII, at the connection with the Trunk Road tunnel
constructed under CRIII and for the crossing over the MTR Tsuen Wan line, the
deep tunnel option must start off as shallow cut-and-cover tunnel, in
reclamation, similar to all other Trunk Road options. At the eastern end, as the tunnel rises
towards the seabed and ground cover becomes insufficient for the TBM
construction, the form of construction needs to change to cut-and-cover tunnel,
with associated reclamation to facilitate this construction along the North
Point shoreline. Therefore
reclamation is still essential and the bored tunnel is not a “no reclamation”
option.
2.6.4
The
major issue associated with a deep tunnel option is that the longer length of
the Trunk Road tunnel along the North Point shoreline, all the way to the
connection with the IEC near the North Point ferry piers, results in extensive
reclamation along this part of the shoreline.
2.6.5
The
issue of reclamation, and whether it is unnecessarily extensive, is the key
concern in this instance. Because
the bored tunnel must rise from a deeper level under the Causeway Bay Typhoon
Shelter than the alternative cut-and-cover tunnel option, the tunnel portal
will need to be located further to the east along the North Point shoreline,
where there is no existing formed land that can be put to good use to
accommodate the ground level tunnel portal, as is the case for the connection
immediately to the east of the CBTS.
As a consequence, the deep bored tunnel option will require a greater
area of reclamation along the North Point shoreline than the alternative
cut-and-cover tunnel option. As the
deep tunnel option will result in a greater area of reclamation than an alternative
available tunnel option, and as in any event the deep tunnel option does not
perform as well as the alternative cut-and-cover tunnel option, there is no
justification or overriding need to pursue this deep tunnel option. Furthermore, the affected area of the
harbour, the foreshore and seabed, will be greater, and the corresponding
environmental impacts, such as marine ecological impacts, would be greater than
the adopted Trunk Road Tunnel Variation 1.
Immersed Tube vs Cut-and-Cover
Tunnel Construction
2.6.6
Immersed
tube tunnel form of construction may be used where the tunnel lies just below
seabed; reclamation would not be required for this form of tunnel
construction. However, this form of
construction is not suitable where the tunnel level rises above seabed level,
as the exposed tunnel section would then be at risk of damage from ship impact,
anchors, etc, the tunnel structure would be more susceptible to degradation in
the aggressive marine environment, and the protrusion of the tunnel structure
above the seabed would restrict marine access to the shoreline. Also, even where the tunnel lies below
seabed level, the soft seabed materials would need to be excavated so that the
immersed tube units lie in a trench on a firm foundation. Along the Wan Chai shoreline, this would
involve excavating a deep trench immediately adjacent to the existing seawalls,
which would undermine these seawalls.
Use of immersed tube is therefore considered not feasible in this
instance, and the most practical and reasonable form of construction for the
Trunk Road tunnel along the Wan Chai shoreline is cut-and-cover, constructed
through reclaimed land.
2.6.7
Through
the ex-PCWA basin and the CBTS, where the Trunk Road tunnel lies below seabed level,
immersed tube or cut-and-cover tunnel construction may be considered. For both forms of construction,
permanent reclamation is not required.
In the case of cut-and-cover tunnel, temporary reclamation may be formed
to facilitate the tunnel construction, but this can be removed on completion of
construction so that the finished product, ie retention of the existing seabed
condition, is the same for both methods.
Factors to be considered in selecting an appropriate construction method
include: whether the tunnel alignment runs wholly through seabed or partly in
existing seabed and partly under existing seawalls and land formation, the
latter making cut-and-cover construction more practically feasible (more
efficient and cost effective construction with less disruption to existing
shoreline facilities and infrastructure) than use of precast immersed tunnel
sections that need to be placed in open trenches; the depth of the tunnel
(where the tunnel lies at a significant depth below the seabed, for example
near the Cross Harbour Tunnel crossing, at –30mPD, major deep and wide trenches
will need to be excavated, making immersed tube construction more disruptive
with greater impacts); or the tunnel length available for immersed tube
construction (short lengths will not be cost effective for the precast
fabrication of tunnel units). The
form of tunnel construction is an important consideration in respect of
avoiding conflict with the SCL, as Trunk Road cut-and-cover tunnel can be
constructed across the future SCL alignment with much closer separation
allowance. Because the Trunk Road
tunnel is on diaphragm wall (piled) supports, it will not be structurally
adversely affected by the construction of the SCL tunnels.
2.6.8
Where
the Trunk Road tunnel rises up above the seabed to ground level, for the
connection with the IEC at the eastern end of the CBTS, cut-and-cover tunnel in
reclamation will again be the feasible form of construction.
2.6.9
In
summary, cut-and-cover tunnel in reclamation is considered to be the practical
and feasible form of construction for implementation of the Trunk Road at the
west of the HKCEC, through the HKCEC water channel, along the Wan Chai
shoreline and through the CBTS.
2.6.10
Cut-and-cover tunnel
construction involves first installing the tunnel walls by using diaphragm
walls (these are reinforced concrete wall panels constructed in existing ground
from ground level down to the required depth, usually to the underlying rock
layer) on both sides of the tunnel, then excavating the soil from between the
diaphragm walls, constructing reinforced concrete top and bottom slabs between
the diaphragm walls to form the tunnel box and, finally, backfilling over the
tunnel. This form of construction
is carried out in existing or formed land to provide the necessary construction
access from the surface – should the tunnel alignment cross over seabed,
reclamation will be required to first form the land through which the diaphragm
walls need to be constructed.
2.6.11
Whereas cut-and-cover tunnel
construction is the practical and feasible form of construction for the overall
Trunk Road, there is localised section underneath the CHT portal approach ramp
where the Trunk Road tunnel will be generally in rock. As mentioned in paragraphs 2.5.3 and 2.5.16 above, the Trunk
Road tunnel will pass underneath the existing rock anchors of the CHT portal
structure. The rock anchors, based
on available as-built information, are installed to a depth of around -17mPD,
therefore, allowing for minimum clearance beneath the anchors, the Trunk Road
must pass beneath the CHT rock anchors and through the rock strata at a road
level of around -30mPD. Drilling
and breaking construction method will be carried out for this section of tunnel
underneath the CHT. Small
diameter drills will be used to drill through the rock to form a honeycomb type
structure in the rock, which would then be easily broken out without the use of
explosives or chemical expanding grouts.
This construction method for hard rock tunnelling is considered to
minimise the impacts on the existing CHT portal structure.
2.6.12
Alternative
construction method like the drill-and-blast method which is normally used for
tunnels through rocky hills and mountains, not for tunnels below seabed with
mixed soil conditions, is considered not applicable in this case.
Piled-Deck Spanning across the MTR
Tsuen Wan Line
2.6.13
The Trunk Road must not impose
any loads on, or cause any movement of, the existing MTR Tsuen Wan Line
immersed tube tunnel. Tunnelling
under the MTR tunnel at sufficient depth to avoid disturbance to the existing
ground and movement of the MTR tunnel would result in exceedance of permissible
tunnel gradients from the connection to the existing road network at the
Central Interchange. A piled Trunk
Road tunnel structure spanning across the MTR tunnel will be constructed to
meet statutory limitations on allowable surcharge, lateral pressure and
movement.
Temporary reclamation for tunnel
below seabed
2.6.14
The
Trunk Road tunnel beneath the ex-PCWA basin and the CBTS will be constructed by
cut-and-cover method, for which reclamation is required (as explained
above). Through these areas,
though, the Trunk Road tunnel structure lies at sufficient depth below the
seabed that consideration can be
given to removing the reclamation after the tunnel has been constructed. The criteria for deciding where the
reclamation can be removed are: that the top tunnel should be deep enough to
allow for adequate structural protection in the absence of the protective
reclamation, and where the tunnel passes through anchorage areas, an additional
seabed layer for ships’s anchor embedment; and that the removal of reclamation
should not have the effect of creating new embayments, in order to avoid water
quality impacts.
2.6.15
Note
that these temporary reclamation areas are not considered as areas affecting
the harbour, insofar as they are short term (for the duration of the
construction period) and solely for the purpose of achieving the end product
(ie in order to ultimately achieve minimum reclamation). The temporary works will not cause
permanent damage to the harbour.
Construction Methods for Other
Infrastructure
2.6.16
A number of existing waterfront
facilities (ferry piers, drainage culverts, cooling water intakes, sewage
outfall, etc.) will be affected by the WDII reclamation. Although these facilities will be
reprovisioned under the Project, they should be kept functional and operational
during reclamation until the reprovisioned facilities are constructed and
available for use. There is
therefore a requirement for reclamation to be carried out in stages, with
careful planning of construction sequence for both the reclamation and
reprovisioning works.
2.6.17
The resultant reclamation
staging creates a number of relatively small and confined areas of land formation. Containment of fill within each of these
areas by seawalls is proposed, with the seawalls constructed first and filling
being carried out behind the seawalls.
This method will allow the land area formed in each stage to be
maximised and also has significant benefits in terms of water quality; by
containing all filling behind seawalls, the release of suspended sediments
during the filling operations will not impact the open water areas of the
harbour.
2.6.18
Seawall construction will, in general,
comprise wave energy absorbing caisson seawall units, where exposed to harbour
waves, constructed on dredged foundations for stability reasons. These caisson seawall units will be in
the form of precast caisson units.
In lieu of casting the precast units at the works site, off-site
(Mainland) precast yard will be used for casting of these precast units and
transportation to the seawall construction site by sea will be the common
alternative adopted for precast works.
2.6.19
Dredging of marine mud is required
for the foundations of the seawalls, culverts, at-grade roads, and associated
with the construction of the CWB tunnel.
The minimum extent of dredging required for foundations of the seawalls,
roads and drainage culverts, and for practical engineering and construction
reasons due mainly to the narrow configuration of the reclamation, effectively
results in a fully dredged approach over the length of the site. Figure 2.6 indicates the proposed extent of dredging for the WDII project.
2.6.20
The use of marine sand fill is
proposed, with fill placed behind the enclosing seawalls of each reclamation
stage. The use of marine sand fill
will enable the formed land to comply with required engineering and settlement
performance criteria, with the fill placed within a very tight programme in
order to meet critical project completion dates. Transportation of marine sand fill will
mainly by barges to achieve the filling rate to meet the construction
programme.
2.6.21
While marine sand is proposed
to be used generally for filling, detailed investigations have been conducted
to explore the possibility of using public fill and surplus rock fill from
appropriate sources that may be identified during the detailed implementation
stages of the project, where engineering, programme and implementation
constraints permit. The
investigations indicate that it is possible to use public fill from Penny’s Bay
Reclamation Stage 2 (PBR2) in the upper formation layers, above +2.5 mPD. For the temporary reclamation where
settlement is not a major concern, public fill from PBR2 for the full depth of
reclamation is proposed, to maximise the use of public fill materials. Transportation of public fill from PBR2
to the works site will mainly by barges as both the supply and demand locations
are at their respective shorelines.
Delivery of reused construction and demolition materials within the site
and/or surplus materials to the public fill reception facilities will be by
barges for large quantities and by truck for local and small quantities.
2.6.22
The reprovisioned Wan Chai East
ferry pier will be a piled structure, similar to the existing pier
structure. Some concrete members or
panels of the ferry pier structure may be in the form of precast units. Similar to the precast caisson units,
besides casting the precast units at the works site, off-site precast yard in
Mainland for casting of these precast units and transportation to the seawall
construction site by sea will be the common alternative adopted for precast
works.
2.6.23
The work site for the project
will be located within the construction works area and the duration of works
are given in the construction programme (Appendix
2.5). Alternatively, precast or
prefabrication work may be carried out at off-site area in Mainland China for casting of concrete
precast units or prefabrication of structural members.
2.7
Operation of the Project
2.7.1
Operational activities, on
completion of the Project, would comprise essentially traffic movements on the
new roads and public use of the waterfront. The RHKYC will continue to operate as at
present. Other than the new
waterfront leisure uses, there are no major changes of land uses which will
result in new operations not already taking place along this shoreline.
2.8
Works Programme
2.8.1
The construction works are
anticipated to commence on site in early 2009, with completion of the project
by 2016. A construction programme
is presented in Appendix 2.5 for
reference.
2.8.2
As noted in Section 2.6 above,
construction needs to be carried out in stages in order to meet the services
and utilities reprovisioning requirements and construction sequencing
constraints. A staged construction
programme, with works in each area being carried out sequentially has been
developed to meet the objectives of the Project. The staging of the reclamation works,
with respect to the above issues and constraints, is shown indicatively in Figures
2.7 to 2.19. A brief description of
the proposed works, with reference to the staging requirements, is given in the
following paragraphs.
Implementation Staging
2.8.3
The construction works can be
considered in terms of three mains works areas being, from east to west, the
North Point and Causeway Bay Reclamation, the Wan Chai Reclamation and the
HKCEC Reclamation.
North Point & Causeway Bay Reclamation
2.8.4
The reclamation at North Point
will be in a two stages. The central
area of reclamation will commence first to provide land for temporary
reprovisioning of the FEHD Depot while the new Depot is under
construction. The reclamation on
either side will follow subsequently but the construction of the Trunk Road
tunnel structure, which is partly on existing land, will commence after the
temporary relocation of the existing FEHD Depot. The land formation at the eastern end of
this reclamation area will be handed over for the construction of the tunnel
approach ramp and connecting to the existing IEC.
2.8.5
The temporary reclamation in
the typhoon shelter is divided into four stages to avoid creating an embayed
water area with a pond of stagnant water between the temporary reclamation and
the existing seawall during construction, and to allow the reuse of filling and
surcharge materials between reclamation stages.
2.8.6
Works for the North Point and
Causeway Bay Reclamation will commence in early 2009. The permanent land formation at North
Point will be completed by late 2010 for handing over of works area for
construction of tunnel approach ramps.
The Trunk Road tunnel structure will be completed by early 2015 for
tunnel installations and fitting out.
Operational completion of the Trunk Road will be in 2016.
Wan Chai Reclamation
2.8.7
Four stages have been proposed
for Wan Chai Reclamation, in addition to the temporary reclamation of the
ex-PCWA basin. The first stage is
constructed between the existing Wan Chai East sewage outfall and the existing
seawater intakes for WSD and Sun Hung Kai.
This land needs to be formed in advance to allow the diversions of the
sewage outfall and seawater intake pipelines.
2.8.8
The following stages, on either
side of this advance reclamation area, are constructed subsequent to the
diversion of the sewage outfall and the seawater intakes. The construction sequencing of these
stages also makes provision for the drainage outfalls from Marsh Road and Canal Road and caters for the temporary
relocation of the Wan Chai to Hung Hom ferry services to temporary berthing
facilities.
2.8.9
Works in this area also
commence in early 2009, with land formation being completed by mid 2013 and the
Trunk Road tunnel structure completed by mid 2014 for tunnel installations and
fitting out. Operational completion
of the Trunk Road will be in 2016.
HKCEC Reclamation
2.8.10
Reclamation in this area takes
place after diversion of the existing cooling water intakes to the intake
chambers already provided on the north side of the HKCEC. Reclamation on either side of the MTR
Tsuen Wan line will follow the bored pile wall construction on either side for
the Trunk Road crossing over the MTR line.
Reclamation of the HKCEC water channel takes place before adjacent
reclamation to either the east or west of the HKCEC Extension so as to avoid
embayment of this confined water area.
2.8.11
Reclamation in this area would
commence in early 2009 and would be completed by mid 2012. The Trunk Road tunnel works would be
completed by early 2014 for tunnel installations and fitting out. Operational completion of the Trunk Road
will be in 2016.
2.9
Related Projects
2.9.1
The following projects are
related to the WDII and CWB project:
(i)
Civil Engineering and
Development Department's CRIII project, comprising reclamation along the
Central waterfront for transport infrastructure needs (including CWB and NIL)
and basic land use requirements. A
section of CWB tunnel will also be constructed under CRIII project. Construction will take place from
February 2003 to September 2012.
(ii)
Trade Development Council’s Atrium
Link Extension project, comprising a link bridge spanning across the water
channel between the Hong Kong Convention and Exhibition Centre (HKCEC) Phase I
and HKCEC Extension.
Construction will take place from May 2006 to March 2009. No cumulative dust impact from the
Atrium Link Extension Project is expected.