15.1.1.1
The Project covers the following designated project
(DP) item under Schedule 2, Part I under the Environmental Impact Assessment
Ordinance (EIAO) (Cap.499) -
|
Item
I.1(b)(ii) –
|
A drainage channel or river training and
diversion works which discharges or discharge into an area which is less than
300m from the nearest boundary of an existing or planned site of cultural
heritage.
|
15.1.1.2
This EIA report has provided an assessment of
the potential environmental impacts associated with the construction and
operation of the Project based on the preliminary engineering design
information available at this stage. The
assessment has been conducted, in accordance with the EIA Study Brief No.
ESB-320/2019 issued under the EIAO for the Project and the EIAO-TM, covering
the following environmental issues.
·
Air Quality Impact
·
Noise Impact
·
Water Quality Impact
·
Waste Management Implication
·
Land Contamination
·
Sewerage and Sewage Treatment Implications
·
Ecological Impact (Terrestrial and Marine)
·
Fisheries Impact
·
Cultural Heritage Impact
·
Landscape and Visual Impacts
15.1.1.3
The findings of this EIA Study have determined
the likely nature and extent of environmental impacts predicted arise from the
construction and operation of the Project.
During the EIA process, specific environmental control and mitigation
measures have been identified and incorporated into the planning and design of
the Project in order to comply with the relevant environmental legislation and
standards during both the construction and operation phases. An environmental monitoring and audit
(EM&A) programme has also been developed.
The Implementation Schedules listing the recommended mitigation measures
are presented in Section 14. A summary of key assessment assumptions and
limitation of methodologies are presented in Appendix 15.1.
15.1.1.4
A summary of the environmental outcomes/benefits
that have accrued from the environmental considerations and analysis during the
EIA study and the implementation of environmental control measures of the
Project are presented in the sections below.
15.2.1
Estimated Populations and Environmentally
Sensitive Areas Protected from Various Environmental Impacts
15.2.1.1
With the implementation of the Project, besides
improving the existing drainage facilities, over 70,000 m2 of
concrete-lined channel space would be transformed into green spaces to promote
greening of the local environment and the ecological value of existing TWN
would be enhanced with the incorporation of the ecological enhancement
features. Furthermore, the introduction
of the DWFI system and treatment wetlands to intercept/polish the existing
polluted discharges at the drainage outlets along TWN, as well as modification
of channel bed downstream of TWN’s broad-crested weir at its confluence with
Shing Mun River near Man Lai Court to reduce excessive accumulation of silts
brought by tidal influence, would improve long-standing water quality and odour
issues associated with the polluted discharges to the nullah and with excessive
siltation at downstream TWN which have been of public concerns as expressed by
Sha Tin District Council (STDC) and local stakeholders. In order to facilitate the public to better enjoy
the view of the revitalised waterscape and ecological enhancement features
(e.g. treatment wetland) as well as to promote water-friendliness, certain
locations of the nullah bank of TWN will be transformed into a green open space
that can be accessed by the public with provision of riparian walkway and
amenity areas for public enjoyment.
There will be multiple large entrance points with stepped seats and
decked platforms on nullah bed that can provide communal spaces for recreation
and leisure activities to promote water friendliness (e.g. riparian walkway,
sightseeing of greening and ecological enhancement features, water play
features equipped with UV disinfection system) at midstream of TWN. Cantilevered viewing decks / sheltered
walkway are also proposed by the bankside in the upstream section.
15.2.1.2
During construction, mitigation measures as
recommended in the EIA will be implemented to protect the identified sensitive
receivers in the vicinity of the Project, including residential
dwellings in Heung Fan Liu, Mei Tin Estate, Granville Garden, Park View Garden
at upstream TWN, Mei Shing Court, Mei Lam Estate,
educational institutes, Man Lai Court and other residential dwellings in Tai
Wai near mid-stream and downstream TWN
from air quality and noise impacts.
15.2.1.3
With the
implementation of DWFI system and treatment wetlands to intercept/polish the
existing polluted discharges at the drainage outlets along TWN, as well as
modification of channel bed downstream of TWN’s broad-crested weir at its
confluence with Shing Mun River near Man Lai Court to reduce excessive
accumulation of silts brought by tidal influence, the odour nuisance of TWN
currently experienced by these air sensitive receivers and general public
visiting TWN would be improved as a result of the operation of the Project.
15.2.2
Environmental Designs Recommended,
Environmentally Friendly Option Considered and Incorporated in the Preferred
Option
Water Quality Improvement and Water
Friendliness
15.2.2.1
Due to ageing drainage systems and possible
expedient connection made in the past, polluted discharges from the existing
drainage outlets along TWN are observed at present. Complaints and concerns from the public,
including Sha Tin District Council (STDC) and local stakeholders, on the
long-standing water quality and odour nuisance of TWN, particular at the
confluence of TWN and Shing Mun River area near Man Lai Court, were
received. With
the implementation of the proposed DWFI system and treatment wetlands, the
existing polluted dry weather flow from the drainage outlets along TWN will
either be intercepted by the DWFI system and discharged to the existing
sewerage system, via gravity mains (i.e. no DWFI pumping station required), to Shatin Sewage Treatment Works for
treatment, or be discharged into the treatment wetlands installed at drainage
outlets for in-situ polishing. Furthermore,
with the modification of channel bed downstream of TWN’s low flow channel near
its confluence with Shing Mun River near Man Lai Court, the excessive
accumulation of silts brought by tidal influence caused by the uneven surface
and flat gradient in front of the broad-crested weir would be greatly
reduced. With the abovementioned
designs, the water quality and hygiene within the nullah would be improved and
odour nuisance to the resident nearby would be alleviated.
15.2.2.3
Freshwater
discharge from the existing drainage
outlet of the nullah near Pok Ngar Villa,
which receives mainly clean river
flow from upstream natural hillside catchment
north to Peak One, will
be partially intercepted and conveyed to
the proposed UV disinfection system for treatment prior to be used in
the water play features (e.g. water spouts and fountains). Based on the preliminary design, no additional
stormwater collection facilities would be required for the conveyance of
freshwater supply for the proposed water play features. DSD Practice Note (PN) No. 3/2021 “Guidelines
on Design for Revitalisation of River Channel” lays out the Water Quality Goals
(WQGs) for primary contact recreation (type 3 designated use) at revitalised
river channel. A more stringent
treatment standard will be adopted for the water supply for the proposed water
play features that in addition to fulfilling the relevant WQGs for type 3 designated
use, E. coli bacteria should be non-detectable (in cfu/100 mL,
calculated as the geometric mean of all samples collected in one calendar year)
in the treated water. There would also
be provision of proper signage and deployment of specific management personnel
to ensure safe and appropriate usage of the water play features. The water play features will be closed when
the disinfection system is not under normal operation, under maintenance or when the treatment standard as specified in the post-revitalisation
water quality monitoring programme established and
implemented by DSD is not compiled with. The detailed designs of the UV disinfection
system and water play features would be conducted in the next stage of the
Project in consultation with relevant Government authorities and reference
would be made to other existing water play features in Hong Kong (e.g. splash
pads, water cascade facilities, water jets and spray grounds etc.).
15.2.2.4
The riparian walkway and amenity areas would be
properly designed to restrict public access / physical contact to the water
body, i.e. the low flow channel, and to ensure public safety (e.g. elevated
walkway design, fencing, provision of warnings / signage, deployment of
specific management personnel etc.). In
particular, it should be noted that neither the water from the revitalised
nullah with improved water quality or the water play features utilising treated
freshwater shall be used for human or animal consumption, bathing or showering,
food preparation / washing. Channel
management system, as well as rain detection, safety and flood warning system
(e.g. water level sensor at the low flow channel) will be adopted and managed
by the DSD and access to the riparian walkway and amenity areas [provided with
water play features] will be closed in case of foreseeable flooding at the
nullah bed or under extreme weather conditions.
Greening Enhancement
15.2.2.5
The existing concrete nullah of TWN will be
resurfaced with layer of vegetation, which will enhance both the aesthetic and
ecological values of TWN. Greening of
the nullah bed and along its banksides, such as provision of emergent wetland
planting (e.g. reed and other aquatic herbs), mangroves, climbing plants, tree
and / or grasscrete etc, will be provided.
The existing mature trees growing by the banksides along the nullah will
be retained, and additional tree planting will be provided along the
nullah. The existing planters will also
be modified to beautify the footpath along TWN.
Ecological Enhancement
15.2.2.6
The existing TWN is of low ecological value in
view of its concrete-lined channel bed and bank, as well
as its limited baseflow, especially in dry season
(i.e. from November to March). With the
proposed modification of the existing stilling basin (part of channel bed
modification works) and the installation of the underground
water pumps installed by the bankside near mid-stream of TWN for associated
water retention and supplement, ecological features will be viable to improve
and create aquatic and terrestrial habitats, enhancing its ecological values.
15.2.3
Key Environmental Problems Avoided and
Compensation Area Included
Avoidance of Natural Habitats
15.2.3.1
All identified natural watercourses are located
in the upper catchment of TWN and outside of the Project site. All natural watercourses and other natural
habitats been avoided under the revitalisation design.
Avoidance and Minimisation of Impacts to Roosting Ardeids
15.2.3.2
Ardeid night roost was recorded along Shing Mun
River nearby the Project, including the mature trees alongside Man Lai Court
and Sha Tin Government Secondary School (Section 9 refers). The ardeid night roosts in vicinity of the
Project have been avoided under the revitalisation design. Under the revitalisation design, existing
concrete channel bank and existing vehicular access at downstream section of
TWN would also be modified into a mix of stepped terrace and slope at water
edge to enhance foraging / pre-roost habitats for waterbirds (e.g. ardeids).
15.2.3.3
No construction works within the nullah in
Section 1 (channel bed modification and desilting at downstream tidal zone)
should be undertaken from 16:30 to 07:30 during dry season (October to March)
and from 17:00 to 07:00 during wet season (April to September) in order to
minimise the potential disturbance to pre-roosting / night-roosting
ardeids. A pre-construction ardeid
survey should be conducted for areas within 100m from the Project site to
confirm the location and status of the night roost. No construction works with PME should be
undertaken within 100m from any night roost should be undertaken from 16:30 to
07:30 during dry season (October to March) and from 17:00 to 07:00 during wet
season (April to September) to avoid disturbance for all work sections 1 – 6 of
TWN.
Protection of Mature Vegetation along TWN
15.2.3.4
There are existing mature trees along TWN on
pedestrian road within the Project site.
Although these tree species are not of conservation importance, the tree
specimens are mature with good foliage and tree crown that can potentially
provide habitat for fauna species, e.g. ardeid night roost. These mature trees will therefore be retained
under the revitalisation design.
Avoidance of Constructions Works within Nullah during Wet Season
15.2.3.5
The construction work within the nullah,
including (including construction of energy dissipation
structures), construction of DWFI system along the
nullah, underground water pipes along the
nullah, construction of riparian walkway and amenity areas, and desilting
works at downstream tidal zone, will only be undertaken during dry season when water is
limited to low flow channel. In addition, site
demarcation and flow diversion as detailed in Section 5.8 will be implemented
to avoid release of sediments/other pollutants into receiving waters.
Minimisation of Construction Disturbances
15.2.3.6
The Project site will be divided into six
sections to be constructed in sequence starting from downstream TWN and the
construction works within each section will be undertaken by parts to reduce
the construction impacts on nearby sensitive receivers as compared to
constructing simultaneously in adjoining sections and areas. Construction works outside the nullah such as
walkway improvement will be scheduled to avoid overlapping with works within
the nullah to avoid heavy construction activities concentrating in a certain
area over any period.
15.2.3.7
As the Project would not cause any loss of
habitat of conservation importance, no compensation area is recommended.
15.2.4
Environmental Benefits of Environmental
Protection Measures Recommended
15.2.4.1
Environmental benefits of environmental
protection measures recommended in this EIA Report are summarised below. No environmental disbenefits would be
envisaged from the proposed revitalisation works.
Air Quality Impact
15.2.4.2
The potential air quality impacts arising from
the construction of the Project would be related to fugitive dust emissions
from construction works and gaseous emissions from the use of PME, and odour
nuisance from
desilted / excavated materials generated during the desilting at downstream tidal
zone / excavation works in the nullah.
In view that the construction works of the Project would be conducted in
section which is small in scale, the air quality impacts would be localised and
minor, and would be well controlled through the implementation of good site
practices and dust suppression measures stipulated in the Air Pollution
Control (Construction Dust) Regulation as well as the proposed good site
practices to minimise the exhaust emissions from NRMMs and odour nuisance from
handling of desilting/excavated materials.
No adverse air quality impact due to the
construction of the Project would therefore be anticipated. Nonetheless, dust monitoring is recommended
during construction phase to ascertain that there would be no adverse
cumulative dust impacts at the nearby sensitive receivers. Regular weekly site audit is also recommended
to be carried out during construction phase in order to confirm that the
mitigation measures are properly implemented and are working effectively.
15.2.4.3
With the introduction of the DWFI system and
treatment wetlands to intercept/polish the existing polluted discharges at the
drainage outlets along TWN, as well as modification of channel bed downstream
of TWN’s broad-crested weir at its confluence with Shing Mun River near Man Lai
Court to minimise excessive accumulation of silts brought by tidal influence,
the odour nuisance of TWN would be alleviated as a result of the operation of
the Project. Any odour emission
generated from exposed desilted materials during the routine maintenance works
would be temporary and confined to the areas of maintenance works that it would
be well-controlled through good site practices.
No adverse air quality impact due to the operation of the Project would
be anticipated.
Noise Impact
15.2.4.4
Noise impact would arise from the use of powered
mechanical equipment during construction phase.
With the proper implementation of the recommended mitigation measures
such as use of quality powered mechanical equipment (PME) / quieter
construction method and movable noise barriers, implementation of good site
practice and proper scheduling construction activities during examination
period of TWGHs Tsoi Wing Sing Primary School, Buddhist Wong Wan Tin College
and TWGHs Sin Chu Wan Primary School, the mitigated cumulative noise levels at
all NSRs would comply with the noise criteria set out in the EIAO-TM. No adverse noise impact is anticipated during
the construction phase of the Project.
15.2.4.5
During operational phase, fixed plant noise from
the operation of the proposed underground water pumps
at mid-stream of TWN for ecological enhancement associated water supplement and
the proposed UV disinfection system for riparian amenity area would be the
major source of noise impacts based on the current design. The noise impact associated with the
operation of the Project has been assessed based on the design information
provided by the Project Engineer at the time of the assessment. The assessment result indicated that the
predicted fixed plant noise levels at all representative NSRs would comply with
the noise criteria. No adverse noise
impact would be anticipated during operational phase of the Project. Commissioning test should be conducted prior
to operation of the Project to ensure that the fixed plant noise impact would
comply with the relevant noise standards.
Water Quality Impact
15.2.4.6
The key issues of the land-based construction
works include construction works at and in close proximity to TWN / inland
water, wastewater generated from general construction activities, construction
site runoff, sewage from construction workforce and accidental spillage of
chemicals. The potential water quality
impacts could be avoided and minimised by implementing the recommended
pollution control measures. No adverse
water quality impact during construction phase would be anticipated. Regular site audit should be undertaken
routinely to inspect the construction activities and works area to ensure the
recommended measures are properly implemented.
15.2.4.8
Despite the reduced environmental baseflow at
the nullah due to the interception of the flow with heavily polluted discharges by the DWFI system, with the provision of treatment wetland for
in-situ polishing of non-intercepted flow with less polluted discharges, the polished flow could serve as a part of
the environmental flow to sustain the ecological function of the flora and
fauna and habitat processes present within the revitalised TWN. Furthermore, owing to the water retention and replenish designs and ecological
enhancement features (e.g. wetland habitats created) within the nullah,
average flow rate would remain similar to baseline condition and no
unacceptable impacts on hydrodynamics properties and hydrology would be
anticipated. Furthermore, with the
modification of channel bed and realignment of low flow channel at downstream
TWN near its confluence with Shing Mun River near Man Lai Court, the
sedimentation before the low flow channel caused by tidal influence and uneven
surface and flat gradient in front of
the broad-crested weir at would be greatly improved. No adverse water quality impact during the
operational phase would therefore be anticipated. Regular weekly site audit during the
construction phase is proposed to inspect the construction activities and works
area to ensure the recommended pollution control
measures are properly implemented.
15.2.4.9
While the Project is expected
to improve the overall water quality of TWN and environmental monitoring for
water quality is not considered necessary for the operational phase under this
EIA study, a post-revitalisation water quality monitoring programme to review
compliance with the Water Quality Goals as stipulated in DSD PN No.
3/2021 will be established and implemented by the DSD.
Waste Management Implications
15.2.4.10
During construction phase, waste types generated
from the Project are likely to include C&D materials from construction
activities, chemical wastes from maintenance and
servicing of construction plants and vehicles, desilted
materials from desilting works at downstream tidal zone, and general refuse
from workforce. In view of the nature
and limited scale of the Project, the quantity of waste arisings would not be
substantial. However, improper handling,
collection, transportation and re-use / disposal of the wastes would likely
give rise to hygiene problems and adverse environmental impacts, e.g. odour
nuisance to local residents, and contamination of the nearby watercourses. Provided that these wastes are handled,
transported and disposed of according to the recommended good site practices
and measures, no adverse environmental impacts (including potential hazard, air
and odour emissions, noise and wastewater discharges) would be anticipated
during the construction phase.
15.2.4.11
The main waste types generated from the
operation of the Project would be silt, debris, screening and limit amount of
chemical waste from the routine maintenance of the DWFI system and nullah as
well as desilted materials from maintenance desilting works. The maintenance practices would be similar to
the existing maintenance works undertaken by the DSD. With implementation of the good waste management practices, adverse environmental
impacts (including potential hazard, air and odour emissions, noise and
wastewater discharges) and public transport impact would not be anticipated
during operational phase. General refuse
would also be generated from the visitors of the revamped public open space
along TWN. Provided that sufficient number of trash
bins and recycling bins have already been provided and would be retained for the collection of general refuse generated by visitors
along TWN, no unacceptable environmental impact and public transport impact
would be anticipated.
Land Contamination
15.2.4.12
Based on the findings of the site appraisal, no
adverse land contamination impact arising from Project is anticipated. No further site investigation works at the
Project site is required. Thus, no
Contamination Assessment Plan / Contamination Assessment Report / Remediation
Assessment Plan are required.
Sewerage and Sewage Treatment Implications
15.2.4.13
A DWFI system is proposed to improve the water
quality in the TWN with intercepted dry weather flow estimated to be at 2,850
m3/day. An additional toilet facility for the visitors in Tai Wai
Nullah located near Pok Ngar Villa with negligible additional sewage flow has
also been proposed. The sewage
impact assessment indicated that existing sewerage system has sufficient
capacity to take up the additional dry weather flow intercepted by the DWFI
system and proposed toilet facility.
Thus, no mitigation measures are required. No adverse sewerage impact arising from the
Project is anticipated.
Ecological Impact (Terrestrial and Marine)
15.2.4.14
A total of nine habitat types were recorded
within the 500 m assessment area from recent surveys, including woodland, mixed
woodland, plantation, grassland, reservoir, village/ orchard, developed area/
wasteland, natural and modified watercourses. Dominant habitat types recorded within
the Project site included developed area and modified watercourse, which are of
low ecological values except for limited sections of the TWN found to support
some wetland vegetation and/or support pre-roost congregation of ardeids and
other wetland birds. These habitats were
considered of low to moderate ecological value.
Species of conservation importance recorded within the assessment area
included eight flora, twelve avifauna, eight mammals, four herpetofauna, five
butterflies, two odonates and two freshwater species. Among these species, only eight avifauna, two
mammal, four butterfly species of conservation importance were recorded within
the Project site.
15.2.4.16
Modified watercourses within the assessment area
[especially alongside downstream TWN from Man Lai Court Block 1 and 2 (Section
1) to Hong Kong Heritage Museum] supported large number of wetland birds
dominated by ardeids, with over 100 individuals congregating on the concrete
access ramps as a pre-roost in the dry season.
15.2.4.17
Whereas ardeid night roost is located within
developed areas within the assessment area, mature trees on the northern bank
of Shing Mun River Channel (from Block 3 of Man Lai Court to Sha Tin Government
Secondary School). Significantly lower
abundance of ardeids were recorded during wet season. No breeding or nursery behaviour of any
wetland avifauna species was identified within the assessment area.
15.2.4.18
No direct impacts to natural habitats within the
assessment area are anticipated for the Project. Direct impacts arising from the proposed
works would be limited to the temporary loss (about 11.1ha) of modified
watercourse and developed area. Given
the relatively low to moderate ecological value of affected habitats, the small
area affected, and the temporary nature of the impact, direct impacts are
expected to be Minor except for minor-moderate scale impacts to two
small stretches of the TWN supporting some wetland vegetation and ardeid
pre-roosting site. All affected areas
will be reinstated and enhanced in terms of ecological value as part of the
Project. Avoidance measures (e.g.
restriction of construction hours, protection of mature trees along the nullah
and avoidance of encroachment of ardeids night roosting sites) would be
implemented to preserve the day roosting and night roosting habitats for bats
and ardeids respectively. Floating platforms
would be installed downstream of the Project site (in the Shing Mun River
Channel) to compensate for temporary loss of the pre-roosting site.
15.2.4.19
Indirect impacts during the construction phase
would comprise of human disturbance, construction noise, dust and site
run-off. With proper implementation of
the recommended mitigation measures and good site practices, no significant
adverse ecological impact is anticipated.
With ecological enhancement measures incorporated into revitalisation
design of TWN and with restriction of public access in Section 1, nature of
disturbance during operational phase would be minimal compared to existing
baseline condition. Net positive
ecological outcome would be result from the created and enhanced wetland
habitats. No unacceptable adverse
residual impacts would therefore be expected during both construction and
operational phase.
15.2.4.20
Ecological monitoring of ardeid usage of the
active pre-roosting and roosting sites confirmed by the pre-construction ardeid
survey, and of the proposed temporary floating pontoons has also been
recommended. Remedial actions can then
be recommended, where appropriate, based on the impact monitoring results. Monthly site audit should also be carried out
throughout the construction phase to ensure recommended avoidance / pollution
control measures are fully implemented.
15.2.4.21
Ecological enhancement designs have been
incorporated into the revitalisation plan to promote ecological value of the
Project, as well as enhancement measures and good site practices to further
minimise any potential environmental impacts.
The proposed revitalisation plan for TWN should seek to find a balance
between design for local communities’ requirements (e.g. aesthetics,
recreation/leisure and access) and ecological enhancement. Ecological enhancement could be achieved by
incorporating habitat creation within and along the TWN to improve the overall
ecological value of the Project site.
The design should not result in disturbance impacts on surrounding
habitats and fauna utilising the nullah.
Upon completion of revitalisation for TWN, ecological value of the
Project site is anticipated to be improved by ecological enhancement measures
incorporated into the design. A
post-enhancement ecological monitoring programme would be developed and
implemented by the DSD to review effectiveness of these enhancement measures
(e.g. creation of wetland habitats, vegetation planting and specific
enhancement measures for identified species).
The programme shall aim to record the overall ecological condition of
the Project site, including but not limited to the followings: quality of the
created habitats and enhancement elements, usage by targeted fauna species and
vegetation conditions. Maintenance and
management requirements for TWN would be adjusted accordingly based on the
monitoring results.
Fisheries Impact
15.2.4.22
The Project would only involve construction
works within the Project area (existing TWN and developed area alongside). No loss of fishing grounds and mariculture
areas are anticipated within the assessment area. With the implementation of the recommended
water pollution control measures, the Project would not cause any unacceptable
indirect impacts to fishing grounds and mariculture areas on fisheries within
the assessment area during both construction and operational phases.
Cultural Heritage Impact
15.2.4.23
Direct impacts from damages through contacting
with construction machineries and site negligence might be anticipated for
Gatehouse of Pok Ngar Villa (new item pending for grading assessment) within
the Project site during construction phase.
Indirect impacts of ground-borne vibration would also be anticipated for
Gatehouse of Pok Ngar Villa (New Item Pending for Grading Assessment), Li
Cottage (Grade 1), Nos. 1-3 First Street, Tai Wai (Grade 3) and Entrance Gate,
Chik Chuen Wai (Grade 2) during construction phase. Appropriate mitigation measures including
pre- and post-condition surveys, buffer zone and monitoring of vibration,
settlement and tilting incorporated with AAA system for the concerned buildings
have been recommended for the built heritages impacted by the Project.
15.2.4.24
A Declared Monument, Old House, Wong Uk Village,
is located within 300m of the discharge area from the revitalised TWN, and
located at about 1.8km from the nearest site boundary. As the proposed works are mostly situated within the TWN and there is substantial separation
distance between the Old House and the proposed works, no direct and indirect impacts on the Old
House would be anticipated during the construction and operation phases of the
Project.
15.2.4.25
As no archaeological potential exists within the
site boundary, and no sites of archaeological interest (SAI) is identified
within 300m from the site boundary, no impact to archaeology would be
anticipated during the construction and operational phases of the Project.
Landscape and Visual Impacts
15.2.4.26
construction phase, the proposed channel
modification and construction of DWFI system and mid-stream water pumps for
ecological enhance associated water supplement will be constructed inside the
existing Tai Wai Nullah, while some proposed architectural structures will be
constructed at the roadside for enhancement of public open space which may
impose visual impact to adjacent VSRs. Based
on the broad-brush tree survey, amongst the 254 nos. of surveyed trees, 202
nos. are proposed to be retained, including all existing mature trees growing
along the nullah. According to the
latest tree treatment proposal, 1 no. of tree of common species (i.e. Sterculia
lanceolata) will be transplanted on-site, and 13 nos. of common species of
trees (i.e. Ficus elastica, Ficus subpisocarpa and Sterculia lanceolata) and
38 nos. of undesirable species (i.e. Leucaena leucocephala) are proposed
to be removed. As stipulated in DEVB TC(W) No. 4/2020, “…the number of
compensatory trees onsite and offsite shall not be lower than that of number of
trees removed including dead trees, but excluding trees of undesirable
species...”, therefore, compensation of the undesirable Leucaena leucocephala would not be required and only 13
nos. of trees would need to be compensated.
Nonetheless, to compensate the loss of existing trees and to further
enhance greening and the amenity value to vicinity of site, approximately 28
nos. of heavy standard compensatory trees are proposed to be planted at
available planting area on-site. With
proper implementation of mitigation measures, all affected LRs and LCAs would
have “moderate” to “insignificant” adverse landscape impacts whilst all
affected VSRs would have “slight” or “insubstantial” adverse visual impacts
except for T2 which would have “moderate” adverse impacts during construction
phase. During operational phase with
implementation of mitigation measures, there will be “insubstantial” residual
visual impacts for most of the VSRs except for T2, which will have “slight”
residual impact significance upon completion of mitigation measures (OM1, OM2,
OM4 & OM5) at Day1 and at Year 10 of operational phase. The provision of new landscaping works and
recreational facilitate along the nullah proposed in this Project can have
beneficial impact to the VSRs throughout the operational phase.
15.2.4.27 Tai
Wai Nullah will be revitalised with architectural and landscape features aimed
at promoting water friendliness and providing an enhanced green and ecological
environment. The proposed architectural
and landscape features and modified channel bed would be the key sources of
visual and landscape changes during operation.
With proper implementation of landscape and visual measures, namely
greening enhancement along channel bed and embankment, provision of
recreational opportunity along nullah, sensitive and aesthetically pleasing
design, re-provision of affected open space, the landscape and visual impacts
are considered as acceptable in accordance to Annexes 10, 11 and 18 of the
EIAO-TM.
15.3
Summary of Key Environmental Impacts
15.3.1.1
A summary of environmental impacts for the
environmental issues in this EIA is presented in Appendix 15.2.
15.4.1.1
A summary of alternative development options and
environmental benefits and disbenefits of different mitigation options is
presented in Section
2.4.
15.5.1.1
The findings of this EIA have provided
information on the nature and extent of environmental impacts arising from the
construction and operation of the Project.
The EIA has, where appropriate, identified mitigation measures to ensure
compliance with the relevant environmental legislation and standards. The EIA report has meet the requirements of
the EIAO-TM and EIA Study Brief No. ESB-320/2019 for the Project.
15.5.1.2
Overall, the EIA Report has predicted that the
Project would be environmentally acceptable with the implementation of the
proposed mitigation measures for the construction and operational phases. An environmental monitoring and audit
programme has been recommended to ensure the effectiveness of recommended
mitigation measures.