Contents
Chapter 13
SUMMARY OF ENVIRONMENTAL OUTCOMES
13.2 Environmental Benefits of the Project
13.3 Environmental Friendly Design Adopted
13.4 Population Protected and Environmental Sensitive
Area Protected
13.5 Approaches Adopted to Minimise/Mitigate
Environmental Impacts
13.1.1.1
According to the
Constituency Boundary Maps 2015 (http://www.elections.gov.hk/dc2015/eng/ebmaps.html), the 500m boundary of the
Project covers five District Council Election Constituency Areas, including
Fung Nin, Shui Pin, Nam Ping, Pek Long and Yuen Long Centre. The total
estimated population of these five areas is about 90,000 in June 2015.
13.1.1.2
Through the delineation of
the site boundary, the design of the elevated pedestrian corridor and the
mitigation measures of the construction programme, the Project would avoid and
minimize environmental impacts on various aspects for the population. This
chapter summarises the overall environmental outcomes due to the development of
the proposed elevated corridor in Yuen Long Town connecting with Long Ping
Station.
13.2
Environmental Benefits of the Project
13.2.1.1
The environmental benefits
of the Project including minimizing the potential nuisance from vehicular emission
and noise on the pedestrians and enhancing the visual and landscape resources
at the street level along the Yuen Long Town Nullah. Details are discussed in Section 2.3.5 and summarized as below:
·
most of the sections of the three major
existing at-grade north-south pedestrian routes from Kau Yuk Road to West Rail
Long Ping Station will experience in general over 50% pedestrian flow reduction
during the peak hour with the provision of the Project. Therefore, less
pedestrians will be subject to the nuisance caused by the vehicular emission
and noise in the vicinity of the Project; and
·
the visual and
landscape resource along both bends of the Yuen Long Town Nullah will be
enhanced by landscape and streetscape works of the Project. In comparing with
the existing channelized nullah with hard concrete surface, the Project will
provide beneficial visual impact to the pedestrians.
13.3
Environmental Friendly Design Adopted
13.3.1
Landscape Works
13.3.1.1
A pleasant environment along the pedestrian corridor will be created
by providing enhanced streetscape design and treatment of site frontages along
the corridor. The pedestrian corridor will be well-lit and be made fully
accessible with ramps, stairs and elevators if necessary. Four viewing platforms will be
provided on the footbridge to allow pedestrians to better enjoy the
neighbouring environment.
13.3.1.2
Within the pedestrian interchanges, plantation areas will be
incorporated to provide an open space for the pedestrians and improve the
visual context of the structures in operation phase. The pedestrian corridor
will not only serve as a linkage, but will also become linear open spaces with
ample space for pedestrian, circulation network and greenery. They will be
designed with the provision of seating urban hard landscape features and visual
landscape amenities for visual relief.
13.3.2
Prefabricated Steel Works
13.3.2.1
Prefabrication of steel works is recommended for the footbridge
structure. This would meet the design
requirements while reducing the disturbance to existing environment. In
construction phase, steel trusses will be prefabricated off-site before they
are transported to the site in the nullah in order to minimize the onsite
works. The completed steel trusses will be launched into position by crane, and
hence massive temporary scaffolding works under the footbridge could be
avoided. This would also help to soften
the visual impacts during the construction phase.
13.3.3
Transparent Rooftop
13.3.3.1
The proposed footbridge
will make use of sunlight for daytime illumination in order to reduce the daytime
use of lighting devices and hence minimize the electricity consumption. According to the current design, about half of
the roof area of the footbridge will be constructed by temped laminated glass.
13.3.4
Phased Implementation
13.3.4.1
There are many environmental sensitive
receivers along the alignment, including both residential uses and education
institutions. Besides, given the urban nature, the separation distances between
the workfronts and these receivers are relatively small and hence they are more
prone to impacts and nuisance during the construction period. Other than
mitigation measures on the noisy items, the construction methodology has been
critically re-examined to ensure that the construction work is implemented in
phases. For example, the temporary erection at the eastern side of the nullah will
be conducted during 2nd to 4th quarter in Year 2018. The
works of different sections of the nullah will be conducted in sequences and
will not in place at the same time. This careful phased implementation will
ensure that only optimal number of construction works will be conducted
concurrently and hence reduced the potential environmental impacts and nuisance
at the outset.
13.4
Population Protected and Environmental
Sensitive Area Protected
13.4.1
Population in the vicinity
13.4.1.1
As mentioned in Section 13.1.1.1,
the total estimated population in the vicinity of the Project is about 90,000
in June 2015. In consideration of there are several residential development
projects (e.g. West Rail Long Ping Station (North) Property Development, West
Rail Long Ping Station (North) Property Development, etc.) will be completed in
coming future, the population in the vicinity of the Project will continue to
grow.
13.4.1.2
Due to the high traffic flow and pedestrian movement within Yuen Long
Town Centre, especially during peak hour and weekend, there are serious traffic
congestion and vehicle-pedestrian conflicts due to narrow roads and footpaths
within the Yuen Long Town Centre. These traffic congestion and
vehicle-pedestrian conflicts issues not only cause safety problems to the
pedestrians but also expose pedestrians to nuisance of vehicular emission and
noise.
13.4.1.3
With the provision of the Project, some of the existing pedestrian flow on
the at-grade footpath will be diverted to the proposed elevated pedestrian
corridor. Under the current situation, there are three major existing
north-south pedestrian routes in Yuen Long Town Centre from Kau Yuk Road to
West Rail Long Ping Station, including (1) along Hong Lok Road and eastern side
of the nullah, (2) along Kik Yeung Road and western side of the nullah, and (3)
along Fung Nin Road, On Shun Street and Chun Yin Square. According to the
latest traffic study, the footpaths across Castle Peak Road - Yuen Long Section
and Kau Yuk Road are the busiest sections of these three pedestrian routes. The
estimated maximum pedestrian flow of these sections ranged from about 1750 to
7310 per hour in Year 2022. With the proposed elevated pedestrian corridor, the
maximum pedestrian flow of these three pedestrian routes would be reduced to about
760 to 4,640 per hour. There are in general over 50% of the pedestrian flow of
most of the sections at the north-south at-grade pedestrian routes will be
diverted to the proposed elevated pedestrian corridor. Therefore, the proposed
footbridge would improve the pedestrian safety as well as minimising the
nuisance of vehicular emission and noise on the pedestrians within the Yuen
Long Town Centre. In addition, the landscape and streetscape works of the Project
will also enhance the visual quality to the pedestrian as well. Hence, it is
considered that the Project would cause beneficial impacts to the population in
the vicinity during the operation phase.
13.4.1.4
The environmental impacts caused by the Project to the population in the
vicinity would occur during the construction phase of the Project. Therefore,
the environmental impacts during the construction phase are examined. It is
anticipated that the Project would not cause any significant environmental
impacts with the implementation of good site practices and site management,
except construction noise.
13.4.1.5
Based on the construction noise assessment, mitigation measures, such as
use of quiet plant and noise barrier, have been recommended to ensure that the
construction noise is controlled to acceptable level, and this would help to
protect the population in the vicinity, especially those at the residential
premises and schools along both sides of the nullah.
13.4.2
Downstream Ecological
Sensitive Area
13.4.2.1
Number of ecological sensitive areas are identified at the downstream of
Yuen Long Town Nullah, including Mai Po Inner Deep Bay Ramsar Site, Deep Bay
Wetland Outside Ramsar Site, Mai Po Nature Reserve, Mai Po Marshes and Inner
Deep Bay SSSIs, and Tsim Bei Tsui and Tsim Bei Tsui Egrety SSSIs, etc.. The
impacts on these ecological sensitive area are minimized and mitigated by
avoiding deteriorated water quality arise from the Project with provision of
mitigation measures, such as use of cofferdams, good site managements,
provision of drainage system, etc., during construction and operational phase
of the Project. Details are given in Section
13.5.3.
13.5
Approaches Adopted to Minimise/Mitigate
Environmental Impacts
13.5.1.1
It can be seen that the design and
construction of the elevated footbridge has adopted the principle to avoid
environmental impacts. Where the impacts could not be avoided, efforts have
been deployed to minimize / mitigate the impact. Notwithstanding this, the EIA
has recommended a package of mitigation measures that would be required. The
Project Implementation Schedule in
Appendix 12.1 has clearly stated the details of such mitigation measures, the
timeframe and the implementation agents. Some of the key mitigation measures
are discussed below.
13.5.2
Provision of Noise Mitigation Measures during Construction Phase
13.5.2.1
Construction noise impact is one of the major
key environmental issues identified for the Project. As mentioned in Section 5.3.5, exceedence of
construction noise criteria is anticipated at the NSRs, including residential
buildings and schools, along the Yune Long Town Nullah without mitigation
measures provided. Therefore, mitigation measures have been considered
throughout the design process to minimize the potential construction noise
impact. Besides good site practices, use of quite plants and working methods,
use of shrouds / temporary noise barriers to screen noise from relatively
static PMEs, scheduling of construction works outside school examination
periods in critical areas and alternative use of plant items within one
worksite would be required during the construction phase to reduce the
construction noise at the NSRs to acceptable levels.
13.5.3
Water Quality to the Nullah and
Downstream Ecological Sensitive Area
13.5.3.1
As mentioned in Chapter 9,
the construction works of the Project will be conducted within and on top of
the Yuen Long Town Nullah, which eventually discharges into downstream
ecological sensitive area including Mai Po Inner Deep Bay Ramsar Site, Deep Bay
Wetland Outside Ramsar Site, Mai Po Nature Reserve, Mai Po Marshes and Inner
Deep Bay SSSIs, and Tsim Bei Tsui and Tsim Bei Tsui Egrety SSSIs, etc. as mentioned
in Section 13.3.3.
13.5.3.2
During construction phase, potential impact to the downstream wildlife
at the ecological sensitive area due to the deteriorated water quality in Yuen
Long Town Nullah arisen from the construction activities, including increased
suspended solid, accidental spillage of chemical and oil into the nullah, etc, would
be one of the key environmental issues of the Project. Therefore, construction
works within the Nullah, such as piling works for the bridge piers, will be
undertaken during dry season. At the start of site establishment, perimeter
cut-off drains to direct off-site water around the site should be constructed
with internal drainage works. Also, cofferdam and temporary platform will be
constructed to constrain the SS release to the river waters during construction
activities. Good site practices and certain mitigation measures will also be
implemented to control construction site runoff. Monitoring of the water
quality will be also implemented to ensure the water quality of the Nullah and
downstream will not be deteriorated by the Project. Emergency actions will be
conducted once unacceptable water quality is identified in order to protect the
downstream ecological sensitive area and wildlife.
13.5.4
Tree Compensation
13.5.4.1
As discussed in Chapter 10, there are 125 tress in the
vicinity of the Project. Based on the tree survey report, 38 trees will be
affected, out of which 1 tree are proposed to be transplanted and 37 trees are
proposed to be felled. All of them belongs to common species. None of them are
LCSD Champion Trees, Registered Old and Valuable Trees nor trees that meet the
criteria for Important Trees. Some compensation planting and transplanting of
trees will be required for mitigating the landscape and visual impact.
13.5.5
Implementation of
Environmental Monitoring System during Construction Phase
13.5.5.1
In addition to the mitigation measures as
described above (see more details in the Project Implementation Schedule), a
comprehensive environmental monitoring and auditing programme would be
implemented to cover various aspects of concern. An independent environmental
checker would also be employed to ensure that all the necessary mitigation
measures are implemented in a timely and orderly manner.
13.5.6
Overall
13.5.6.1
With the provision of the Project, there will
be in general over 50% pedestrian flow reduction during the peak hour in most
of the sections of the three major at-grade north-south pedestrian routes from
Kau Yuk Road to West Rail Long Ping Station. Therefore, less pedestrians will
be subject to the nuisance caused by the vehicular emission and noise in the
vicinity of the Project.
13.5.6.2
Besides, the visual and landscape resource
along both bends of the Yuen Long Town Nullah will be enhanced by landscape and
streetscape works of the Project. In comparing with the existing channelized
nullah with hard concrete surface, and the disorder street element, the Project
will provide beneficial landscape impact to the pedestrians. In visual point of
view, the proposed footbridge will unavoidably cause
visual obstruction to the existing visual corridor and adverse visual impact,
by taken account into the overall visual impact to all VSRs are mostly slight
to insubstantial, and the functional requirement of the project, the works is
considered as marginally acceptable in visual point of view.
13.5.6.3
Mitigation measures and good site practices
to minimise the environmental impacts were recommended throughout the impact
assessments such as noise, water quality, landscape and visual, etc. These
measures were consolidated in the Project Implementation Schedule which
specifies the responsibility, methodology and timing of implementation, such
that effective and appropriate implementation of the measures can be assured.