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10. LANDSCAPE & VISUAL IMPACT ASSESSMENT
10.1 Introduction
This Section presents the Landscape and Visual Impact Assessment (LVIA) for the proposed
Project in South Lantau. Potential landscape and visual impacts have been assessed in
accordance with the criteria and guidance set out in the EIAO Guidance Note No. 8/2010 and
the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM), in
particular Annexes 10 and 18 and other legislation as detailed in Section 10.3.
The landscape impact assessment considers the potential impacts of the Project on the
existing landscape and particularly on the landscape resources within 500 m of the Project
Site.
The visual impact assessment analyses the potential visual impacts of the proposed Project on
the existing views and the visual amenity within the visual envelope.
The main components of the LVIA section are as follows:
Key components of the Project for LVIA purpose;
A list of the relevant environmental legislation, standards and guidelines;
Review of the planning and development control framework;
Landscape section including:
landscape impact assessment methodology;
landscape baseline study providing a description of the baseline landscape
resources (LRs) and landscape character areas (LCAs) within the Study Area and
an assessment of their sensitivites;
identification of potential sources of landscape impacts during construction and
operation of the Project;
prediction of nature of landscape impacts, the magnitude of change and their
potential significance before the implementation of mitigation measures;
recommendation of appropriate mitigation measures during construction and
operation and associated implementation programmes; and
prediction of the significance of landscape impacts after the implementation of the
recommended mitigation measures.
Visual section including:
visual impact assessment methodology;
visual baseline study, providing details of visual elements around the Project site
and the Visually Sensitive Receivers (VSRs) within the visual envelope;
identification of potential sources of visual impacts during construction and
operation of the Project;
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prediction of nature of visual impacts, the magnitude of visual change and the
potential significance of impacts before the implementation of mitigation
measures;
recommendation of appropriate mitigation measures during construction and
operation and associated implementation programme; and,
prediction of the significance of visual impacts after the implementation of the
recommended mitigation measures.
Assessment of the residual impacts and conclusion on the acceptability of the Project
according to the five criteria set out in Annex 10 of the EIAO-TM.
10.2 Key Components of the Project for LVIA purpose
The major elements of the Project include a village sewerage system, a trunk sewerage
system, and a STW as illustrated in Figure 1.1. The proposed sewerage system will collect
the sewage generated from the unsewered areas of Shui Hau, Tong Fuk, Cheung Sha, San
Shek Wan, Pui O and Ham Tin in South Lantau (i.e. within the Project Catchment Area) and
convey it to the proposed STW at San Shek Wan for treatment and disposal into the outer bay
of Pui O via a submarine outfall.
The superstructure of the administration building and operation building for the STW will be
of an area of about 35m (L) x 8m (W) x 13m (H) and 45m (L) x 36m (W) x 13m (H). The
submarine outfall is approximately 1,100 m long (marine portion) and includes a diffuser in
the outer bay of Pui O Bay.
The village sewerage works will involve the construction of underground gravity sewers
inside the unsewered areas of the villages and construction of underground trunk sewers
along South Lantau Road. Above ground facilities will include six trunk Sewage Pumping
Stations (SPSs) in Shui Hau, Tong Fuk, Cheung Fu Street, Cheung Sha, San Shek Wan and
Pui O, as indicated in Figure 1.1, each enclosed in a single-storey superstructure with
approximate dimensions shown in below table. Some equipment, such as pump units and
wet wells, will be underground at these SPS.
Sewage Pumping Stations
(SPSs)
Approximate dimension above ground (L x
W x H)
Shui Hau SPS 14.2m x 12m x 6.3m
Tong Fuk SPS 14.2m x 12m x 4.8m
Cheung Fu Street SPS 16.4m x 10.8m x 7m
Cheung Sha SPS 18.8m x 8m x 6m
San Shek Wan SPS 15.4m x 15.2m x 7m
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Pui O SPS 20.1m x 10.2m x 6m
Open-cut excavation would be the predominant method for laying of the proposed sewers
and rising mains and construction of manholes. The works on narrow areas inaccessible by
vehicles or where working space is limited will be carried out by hand-held tools or small-
scale construction plant equipment for activities such as excavation, pipe laying and
backfilling. Trenchless construction method will be considered for laying the proposed
sewers and rising mains crossing major roads, road junctions or sensitive locations if
necessary to minimize potential impacts to existing traffic or the public. It would also be
adopted in the locations where open-cut excavation is not practicable. The proposed
sewerage will be constructed and commissioned from downstream to upstream and will be
constructed in sections with a temporary traffic arrangement implemented during
construction to maintain the traffic flow of South Lantau Road.
Some site clearance and site formation work would be required at the proposed STW and
SPS sites.
For the proposed submarine outfall, Horizontal Directional Drilling (HDD) method would be
used for its construction, with minor seabed dredging for the installation of the outfall
diffuser.
A more detailed description of the Project and construction methods can be found in Sections
2 and 3.
10.3 Legislation Requirement & Assessment Criteria
The LVIA was undertaken in accordance with the following guidelines and requirements:
EIA Study Brief No. ESB-209/2009;
Annexes 10 and 18 of the EIAO-TM under the EIAO (Cap. 499), entitled Criteria for
Evaluating Visual and Landscape Impact, and Impact on Sites of Cultural Hetritage
and Guidelines for Landscape and Visual Impact Assessment respectively;
EIAO Guidance Note No. 8/2010 Preparation of Landscape and Visual Impact
Assessment Under the Environmental Impact Assessment Ordinance;
DEVB TC(W) No. 6/2015 - Maintenance of Vegetation and Hard Landscape Features;
DEVB TC(W) No. 7/2015 – Tree Preservation;
DEVB Greening, Landscape and Tree Management Section (GLTMS) (9/2014) –
Guidelines on Trees Transplanting;
DEVB GLTMS (12/2014) – Management Guidelines for Mature Trees
DEVB GLTMS (04/2015) – Guidelines on Tree Preservation during Development
Land Administration Office Instruction (LAOI) Section D-12 Tree Preservation;
Hong Kong Planning Standards and Guidelines; Chapter 4 - Recreation, Open Space
and Greening (updated 2015), Chapter 10 Conservation (updated 2010), Chapter 11 –
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Urban Design for Hong Kong and ‘Section 7 Use of Land Beneath Flyovers and
Footbridges’ of Chapter 12 Miscellaneous Planning Standards and Guidelines);
Urban Design Guidelines for Hong Kong (1)
; and
Study on Landscape Value Mapping of Hong Kong
And with due consideration also for:
Town Planning Ordinance (Cap. 131); and
Country Park Ordinance (Cap. 208).
10.4 Planning and Development Control Framework
The proposed Project site lies within the Approved South Lantau Coast Outline Zoning Plan
(OZP) No. S/SLC/19 approved in September 2014. Over half of the Study Area falls within
the Lantau South Country Park designated under the Country Parks Ordinance in 1978. The
OZP No. S/SLC/19 and Country Park boundaries are shown in Figure 10.4.1 and Figure
10.4.2.
The OZP No. S/SLC/19 area covers a total of approximately 2,455 ha along the South Lantau
Coast. In the north, it is almost all bounded by the Lantau South Country Park (CP) and in
the south by the existing coastline. Some parts of the Country Park also fall within the OZP
area.
The Study Area is heavily vegetated with scattered, low-rise residential developments along
the foothills and highly rural in nature. In order to conserve this rural character, excavation
or filling of land, stream diversions and large-scale developments are discouraged by the
OZP and development is also discouraged within the CP. The existing population of the area
concentrates mainly at several recognized villages, including those of the Project, and
according to the 2011 population, the total population in the whole OZP area was about 6,350
persons which included about 2,400 inmates and residents in staff quarters of several penal
institutions. It is estimated that the planned population in this area will be about 8,450
including about 3,700 inmates and residents in staff quarters of the penal institutions. During
weekends and public holidays, there are also many visitors to the area.
A detailed list of how each of the proposed above ground structures of the Project affects the
Zoning Types under S/SLC/19 is presented in Table 10.1.
Table 10.1 – Zoning Types and Areas affected by the Project
Proposed Above Ground
Development
Zoning Types Affected
(Total Area within OZP)
Zoning Area affected (ha)
Proposed Shui Hau Trunk
SPS
Coastal Protection Area (CPA) (162.46 ha) 0.11
Proposed Tong Fuk Trunk
SPS
Coastal Protection Area (CPA) (162.46 ha) 0.06
Proposed Cheung Fu Street
Trunk SPS
Residential (Group C) (R(C)) (57.09 ha) 0.07
Green Belt (GB) (481.64 ha) 0.01
Total: 0.08
(1) PlanD. Urban Design Guidelines for Hong Kong Available at:
http://www.pland.gov.hk/pland_en/p_study/comp_s/udg/udg_es/dig_eng/urban_cover.htm [Accessed June 2016]
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Proposed Above Ground
Development
Zoning Types Affected
(Total Area within OZP)
Zoning Area affected (ha)
Proposed Cheung Sha Trunk
SPS
Coastal Protection Area (CPA) (162.46 ha) 0.04
Proposed San Shek Wan
Trunk SPS
Coastal Protection Area (CPA) (162.46 ha) 0.14
Proposed San Shek Wan
Trunk SPS – Alternative
Option
Coastal Protection Area (CPA) (162.46 ha) 0.17
Proposed Pui O Trunk SPS Coastal Protection Area (CPA) (162.46 ha) 0.18
Proposed San Shek Wan
STW
Coastal Protection Area (CPA) (162.46 ha) 0.56
Most of the proposed above ground development falls within the Coastal Protection Area
(CPA). The CPA is intended to conserve, protect and retain the natural coastlines and the
sensitive coastal natural environment, including attractive geological features, physical
landform or area of high landscape, scenic or ecological value, with a minimum of built
development. It is also intended to safeguard the beaches and their immediate hinterland and
to prevent haphazard ribbon development along the South Lantau Coast. While there is a
general presumption against development within this zone, essential infrastructure projects
with overriding public interest may be permitted. As the Project is considered of public
interest, it does not conflict with the planning intention in this zone.
The proposed Cheung Fu Street Trunk SPS is the only SPS to affect other zoning types,
namely Residential (Group C) (R(C)) and Green Belt (GB). In reality the vast majority of
this SPS site lies on R(C) zoning (See Figures 10.4.1-2) where the planning intention is
primarily for low-rise and low-density residential developments. Construction of flats,
houses, post office and police reporting centre, and utility installations for private projects are
always permitted in this zone. Given the SPS is a low-rise structure affecting a very small
area (in total 0.08 ha) it is assumed that it does not conflict with the planning intention in this
zone.
The proposed SPSs are regarded as ‘Public Utility Installation’ and the proposed STW may
be considered as a ‘Public Utility Installation’ or ‘Sewerage Treatment/ Screening Plant’ on
the“Definition of Terms used in Statutory Plans”. According to the Notes of the OZP
S/SLC/19, ‘Public Utility Installation’ requires planning permission from the Town Planning
Board on areas zoned “GB”, “R(C)” and “CPA”. However, should the proposed STW is
regard as ‘Sewerage Treatment/ Screening Plant’, it is neither a Column 1 nor Column 2 use
on the CPA” zone. Amendment of the OZP maybe required for the proposed STW
development. In addition, excavation of land within “CPA” zone requires planning
permission from the Town Planning Board.
10.5 Tree Survey
A broad brush tree survey was undertaken focusing on trees within each of the proposed sites
for the STW and SPS in March 2012, as these sites would be most likely to be directly
impacted by the proposed Project. The sites include the proposed trunk SPS at Shui Hau,
Tong Fuk, Cheung Fu Street, Cheung Sha, San Shek Wan (both the currently proposed site
and an alternative site) and Pui O; and the STW at San Shek Wan. At each site, the estimated
numbers of trees falling within the Project site was recorded, as well as the range of tree
Diameter at Breast Height (DBH), height and dominant species. The results are detailed in
Section 10.6.6.
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The survey also considered trees that may potentially be affected by the installation of the
village and trunk sewerage systems, particularly along South Lantau Road.
It is expected that a Tree Felling Application will be prepared in accordance with the relevant
guidelines/ requirements during the detailed design stage and the loss of any trees will be
compensated for accordingly, as outlined in Section 10.6.8.
10.6 Landscape Impact Assessment
10.6.1 Methodology
In accordance with Annex 18 of the EIAO-TM, the Landscape Impact Assessment (LIA)
considers the potential impacts of the Project on the existing landscape resources within the
Study Area, i.e. within 500m of the Project Boundary. The LIA covers the following tasks:
Identification and mapping of the baseline Landscape Resources (LRs) and
Landscape Characters Areas (LCAs) within the Study Area. This was achieved
through site visits as well as a desk-top study of topographical maps with reference to
Landscape Value Mapping of Hong Kong and photographs. Where appropriate,
information from the tree survey described in Section 10.5 is extracted to supplement
information regarding the baseline conditions, impact assessment and mitigation
measures.
Assessment of the sensitivity of LRs/LCAs. This is influenced by a number of factors
including whether the LR/LCA is common or rare, whether it is considered to be of
local, regional, national or global importance, its conservation value, whether there are
any statutory or regulatory limitations/requirements relating to the resource, the quality
of the LR/LCA, the maturity of the LR, and the ability of the LR/LCA to accommodate
change. The sensitivity of each LR and LCA is classified as follows:
(a) High: Important landscape resource or landscape of particularly distinctive character or high importance, sensitive to relatively small changes;
(b) Medium: Landscape resource or landscape of moderately valued landscape character, reasonably tolerant to change; and
(c) Low: Landscape resource or landscape with a nature which is largely tolerant to change.
Identification of potential sources of landscape impacts. The various elements of
the construction and operation works that have the potential to cause landscape impacts
are indentified and noted. Relevant drawings are provided to illustrate the potential
sources of landscape impact.
Identification of the magnitude of change from landscape impacts. The magnitude
of change depends on a number of factors including the physical extent of the impact,
the landscape context of the impact, the compatibility of the Project with the
surrounding landscape; and the time-scale of the impact, i.e. whether it is temporary
(short, medium or long-term), permanent but potentially reversible, or permanent and
irreversible. Particular LRs/LCAs may not be affected by the Project in which case
“n/a” is denoted to show assessment of that factor is not applicable in identifiying the
magnitude of change. The tree survey helps identifying the extent of the physical
extent and landscape context of the impact and the overall magnitude of landscape
change is classified as follows:
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(a) Large: The landscape resource or landscape will experience a major change;
(b) Intermediate: The landscape resource or landscape will experience a moderate change;
(c) Small: The landscape resource or landscape will experience slight or barely perceptible changes; and
(d) Negligible: The landscape resource or landscape will experience no discernible change.
Identification of potential landscape mitigation measures. These may take the form
of adopting alternative designs or revisions to the architectural design to prevent and/or
minimise adverse impacts; remedial measures such as colour and textural treatment of
structural features; and compensatory measures such as the implementation of
landscape design measures (e.g. tree planting) to compensate for unavoidable adverse
impacts and to attempt to generate potentially beneficial long-term impacts. According
to EIAO Guidance Note No. 8/2010, the mitigation measures should be agreed by
relevant parties in respect of the responsibility of funding, implementation,
management and maintenance of the proposed mitigation measures prior to their
inclusion into the LVIA. Agreement has been sought with relevant agencies
responsible for funding, implementation, management and maintenance, and are listed
under Table 10.5 against the proposed mitigation measures.
Prediction of the significance of landscape impacts before and after the
implementation of the mitigation measures. By synthesising the magnitude of the
various impacts and the sensitivity of the various landscape resources the potential
impacts will be categorised in a logical and consistent fashion. Table 10.2 shows the
rationale for dividing the degree of significance into four thresholds, namely
insignificant, slight, moderate, and significant, depending on the combination of a low-
medium-high degree of sensitivity of LR/LCA with a negligible-small-intermediate-
large magnitude of change. The significant thresholds are defined as follows:
(a) Substantial: Adverse/beneficial impact which will cause significant deterioration or improvement in existing landscape quality.
(b) Moderate: Adverse/beneficial impact which will cause a noticeable deterioration or improvement in existing landscape quality.
(c) Slight: Adverse/beneficial impact which will cause a barely perceptible deterioration or improvement in existing landscape quality.
(d) Insignificant: The impact will cause no discernible change in the existing landscape quality.
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Table 10.2 – Impact Significance of Landscape or Visual Impact Receptor Sensitivity
(LR/ LCA/ Visually Sensitive Receiver) Low Medium High
Ma
gn
itu
de
of
cha
ng
e Negligible Insignificant Insignificant Insignificant
Small Slight Slight / Moderate* Moderate
Intermediate Slight / Moderate* Moderate Moderate / Substantial*
Large Slight / Moderate* Moderate / Substantial * Substantial
* In those instances where the lower level of impact is predicted, this is justified in the description of the
impact
Prediction of Acceptability of Impacts. An overall assessment of the acceptability, or
otherwise, of the impacts has been carried out to determine whether the impacts to the
landscape are beneficial, acceptable, acceptable with mitigation measures, unacceptable
or undetermined.
10.6.2 Baseline Landscape Conditions
The proposed Project is located in Shui Hau, Tong Fuk, Cheung Sha, San Shek Wan, Pui O
and Ham Tin in South Lantau. Within the Study Area, there are a number of low-rise
residential developments, recreational facilities and governmental or institutional buildings.
To the north of the site are sloping hill sides containing mostly natural vegetation. To the
south of the site is open seascape. The area comprises extensive densely vegetated hill slopes
forming a scenic natural backdrop for the villages and low-rise, low-density residential
developments scattered along the foothills. The dominant coastal topographical features are
the hilly peninsulas of Lo Kei Wan to the west of the Project site and Chi Ma Wan to the east,
with the coastal strip in between having a number of beaches and mangrove areas. There are
gazetted public beaches here including Tong Fuk Beach, Upper Cheung Sha Beach, Lower
Cheung Sha Beach and Pui O Beach. Pockets of dense woodland can be found in some areas
within the Country Park and in patches of coastal lowland north of South Lantau Road.
The LCAs and LRs of the Study Area have been categorised according to the presence of
common elements. These may include factors such as topography; vegetation type (both
species and age); built forms; evidence on human modifications; land use (past and present);
and edges.
10.6.3 Landscape Character Areas
Four LCAs have been identified within the Study Area and are mapped in Figure 10.6.1 (key
plan) with more details shown in Figures 10.6.1a-f. Figure 10.6.3.1 shows representative
photographs of each LCA. The ratings of LCA sensitivity are assessed below, in terms of the
various factors listed in the methodology.
LCA1 – South Lantau Coastal Uplands and Hillsides. This LCA comprises uplands
and hillsides adjacent to the coast between the Lo Kei Wan and Chi Ma Wan
peninsulas, predominantly lying below 300 mPD and going down to sea level in some
areas. There are almost no built forms in this LCA, which is highly vegetated by
relatively mature scrubland, woodland and some patches of plantation. Whilst this
LCA is common in Hong Kong, it is of high conservation value due to its naturalness
and undisturbed nature, and some areas are protected as they fall inside the Lantau
South Country Park and Green Belt. This LCA is of high quality with limited ability to
accommodate change and itssensitivity is considered to be high.
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LCA2 –South Lantau Coastal Settled Valleys. This LCA is composed of valleys
where they meet the sea mainly around river or stream estuaries. It is populated by
scattered low-rise villages and buildings with easy access to the sea and generally has
low-lying topography. This LCA has significant human settlement i.e. is developed,
but also has significant vegetation including some woodland and plantation of varying
maturity, as well as small areas of agricultural lands and marsh. This LCA is common
in Hong Kong, and those areas that are protected as Lantau South Country Park, Green
Belt and Coastal Protection Areas are considered to be of conservation value. This LCA
is considered to be of medium quality due to the amount of development it contains
which makes it adaptable to change and its sensitivity is considered to be medium.
LCA3 – Shui Hau Wan Intertidal Coast. This LCA describes the large intertidal area
at Shui Hau Wan which is a sandy/muddy area but also includes some mangrove
patches. This is a mature and less common LCA in Hong Kong, which contains
horseshoe crab nursery grounds of local ecological importance. This LCA also
comprises a proposed Site of Special Scientific Interest (SSSI) and is thus of
conservation value and high quality. There are no buildings in this LCA and it has
limited ability to accommodate change. Its sensitivity is considered to be high.
LCA4 –South Lantau Bay Landscape. This LCA describes the coastal water bound
by Lo Kei Wan peninsula in the west, the continual coastline along Shui Hau Wan,
Tong Fuk Miu Wan, Tong Fuk Beach, Upper Cheung Sha Beach, Lower Cheung Sha
Beach and Pui O Wan to the Chi Ma Wan peninsula in the east. This LCA is common
in Hong Kong. This LCA includes some mangrove areas of conservation value around
Pui O and is considered to be of high quality. It is considered to have high sensitivity.
10.6.4 Landscape Resources
Ten LRs have been identified within the Study Area and are mapped in Figure 10.6.2 (key
plan) with more details shown in Figures 10.6.2a-f. Figures 10.6.4.1-2 show representative
photographs of each LR. The ratings of LR sensitivity are assessed below, in terms of the
various factors listed in the methodology including quality, maturity and ability to
accommodate change .
LR1 – Woodland. This LR consists of large areas of trees growing mainly on the
upland and hillside areas, but also some areas closer to the shore at lower elevations.
These woodlands vary in maturity and have a canopy height ranging between 5-12 m
on average. Species vary in different areas but are dominated by a mixture of native
pioneer species including Schefflera heptaphylla, Sapium sebiferum, Claoxylon
indicum, Zanthoxylum avicennae, backshore species including Hibiscus tiliaeceus and
Pandanus tectorius. This LR also includes some relatively old woodland behind Shui
Hau, Tong Fuk, Ham Tin and Pui O villages, in which woodlands behind Shui Hau and
Tong Fuk are recognised as Fung Shui woodland by AFCD (Figures 5.4a-m), giving it
high local significance. Species in these areas include Aquilaria sinensis, Schefflera
heptaphylla, Ficus variegata, Cinnamomum camphora and Aporusa dioica. Whilst this
LR is common in Hong Kong, it is of high conservation value due to its naturalness and
undisturbed nature, and some areas are protected as they fall inside the Lantau South
Country Park and Green Belt. This LR is thus of high local importance and high
quality. Overall this LR is relatively intolerant to change and its sensitivity is high (2)(3)
.
(2) Environment, Transport and Works Bureau Technical Circular (Works) No. 5/2005 - Protection of natural streams/rivers from adverse impacts
arising from construction works
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LR2 – Scrubland. This LR is the predominant LR on the uplands and hillsides within
the Study Area. Vegetation includes shrubs up to 3 – 5 m tall and in a few places it has
been formed by prolonged abandonment of cultivated land. The tree and shrub species
most evident in this LR include Sapium sebiferum, Rhus chinensis, Aporosa dioica,
Litsea glutinosa, Claoxylon indicum, Rhodomyrtus tomentosa, Rhaphiolepis indica and
the fern species Dicranopteris pedata. This LR is common in Hong Kong, and those
areas that are protected as Lantau South Country Park, Green Belt and Coastal
Protection Areas are considered to be of conservation value. This is a naturally
vegetated LR but is often changed by hill fires during grave sweeping festivals which
keeps the vegetation relatively immature and of medium quality, with medium
tolerance to change. Its sensitivity is medium.
LR3 – Plantation. This LR contains planted trees and is largely located along
roadsides, within and around developed areas and above catch water although there is
also a large area east of San Shek Wan and Pui O Wan from the coast up to the catch
water of the Lantau Trail. Most trees in this LR are exotic species, including Acacia
confusa, Casuarina equisetifolia and Pinus elliotii. This LR is common in Hong Kong,
and those areas that are protected as Lantau South Country Park, Green Belt and
Coastal Protection Areas are considered to be of conservation value. This is an LR
planted by man and despite its tall canopy the plantation is considered relatively
immature and of medium quality, and its overall sensitivity is medium.
LR4 –Agricultural Land. Patches of this LR are scattered within the Study Area
covering a small total area, found mainly near villages, marshes and some on hillside,
including tree nurseries, orchards, and vegetable fields some of which appear currently
unused. This LR is less common in Hong Kong, and those areas that are protected as
Green Belt and Coastal Protection Areas are considered to be of conservation value.
This is a man-made LR with medium landscape quality and with suitable conditions
can be recreated i.e. can accommodate some change. Its sensitivity is medium.
LR5 – Urban/ Village Area. This LR includes the villages of Shui Hau, Tong Fok,
Cheung Sha, San Shek Wan, Pui O and Ham Tin as well as the penal institution at Tong
Fuk and large areas of modified landscape such as that near the junction of the new
Tung Chung Road with South Lantau Road. It also includes South Lantau Road itself
and the new and old Tung Chung Roads as well as the cemented landing site at Tong
Fuk and the road leading down to this. This LR is mainly modified but has some
vegetation including village trees and private amenity planting which, along with the
traditional village houses and ancestral halls also found within this LR, are vulnerable
to the change. This LR is common in Hong Kong and of low conservation value.
Overall this LR has limited greening, is low to medium quality and has a reasonable
tolerance to change. Its overall sensitivity is considered medium.
LR6 – Stream/ Channel. The key streams/channels in the Study Area, are: Pui O
Stream, San Shek Wan Stream, Cheung Sha Stream, Tong Fuk Stream and Shui Hau
Stream, two of which (Pui O Stream and Tong Fuk Stream), are considered as
Ecologically Important Stream (EIS) by the AFCD with high conservation interest.
The flows at the upper courses of these streams are often channelized where they meet
the catchwater whereas the middle courses are fairly natural and the lower courses are
(3) AFCD (2005) Biodiversity News Letter Issue 8
Available at: https://www.afcd.gov.hk/tc_chI/publications/publications_con/files/hkbonewsletter8.pdf
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subject to different levels of modification as they pass under roads and through villages
and cultivated land before reaching the sea. Other natural streams can be found near
San Shek Wan and Cheung Sha and riperian species recorded in this LR include
Cleistocalyx operculata and Sterculia lanceola. This LR is not common in Hong Kong,
and those areas that are upstream and less disturbed are considered to be of high
conservation value and high quality. The sensitivity of this LR is considered high.
LR7 – Rocky Shoreline. This LR is made up of general rocky shoreline. Much of
Hong Kong’s shoreline is made up of this type of exposed rocky shoreline but this LR
falls in areas of Coastal Protection Area and although it is not an ecologically important
habitat, it is a mature LR of good quality and limited ability to accommodate change.
This LR is common in Hong Kong, and those areas that are protected as Coastal
Protection Areas are considered to be of conservation value. Overall the sensitivity or
this LR is considered high.
LR8 – Sandy Beach. This LR includes the gazetted beaches within the Study Area
such as at Cheung Sha and Tong Fuk but also the intertidal sandy/muddy area at Shui
Hau Wan. Some shrubby vegetation can be found in a narrow belt at the rear side of
the sandy shores and this LR is relatively intolerant to change. The gazetted beaches
are also used by a large number of visitors and are of good quality. This LR is common
in Hong Kong, and those areas that are protected as Coastal Protection Areas are
considered to be of conservation value. This LR’s sensitivity is high.
LR9 – Seascape. This LR comprises the sea in the Study Area. This LR is used for
recreation and of conservation value as it is protected by local legislation including the
Water Pollution Control Ordinance. The seascape is considered of good quality. Its
sensitivity is considered medium.
LR10 – Marsh/ Estuarine. This LR is located in three main areas; Shui Hau Wan,
Tong Fuk and Ham Tin and much of it has been formed from abandoned agricultural
land near streams and fed by brackish water. The marsh/estuarine area at Shui Hau
falls in /near a proposed Site of Special Scientific Interest (SSSI). At Tong Fuk the
marsh/ estuarine area is relatively small and appears to have been formed from
abandoned arigultural land. The Ham Tin marsh/estuarine area (also covering Pui O
area) has mangroves that are ecologically important but also large areas of abandoned
agricultural land. The small areas of mangrove around Shui Hau and Ham Tin include
species such as Avicennia marina, Aegiceras corniculatum and Kandelia obovata.
Other vegetation consists of remnant crop species such as Colocasia esculenta, riperain
species including the water fern Azolla imbricate as well as Cyclosorus interruptus,
Marsilea quadrifolia, Salvinia natan, grass species including Panicum repens and
Paspalum paspaloides, and some pioneer tree species including Sapium sebiferum and
Ficus hispida. Overall this LR is common in Hong Kong, and those areas that are
protected as Coastal Protection Areas are considered to be of conservation value. Some
areas of this LR have been developed upon and some of the vegetation is weed species
but overall it natural of good quality and fairly intolerant to change making its
sensitivity high.
10.6.5 Identification of Potential Sources of Landscape Impact
The Project, as described in detail in Section 3, will have various potential landscape impacts
during construction and operation as described below (Note these will also cause visual
impacts).
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-12 B&V / ERM
Construction Phase
During the construction phase of the Project, potential impacts could result from the
following:
Site clearance;
Site formation works including excavation, concreting and backfilling;
Temporary access to construction sites;
Open-cut excavation and re-provision of surfaces within the villages and along South
Lantau road;
Trenchless construction, in certain areas to be finalised, when laying the proposed
sewers and rising mains crossing major roads, road junctions or at sensitive locations or
where open-cut excavation is not feasible;
Presence and operation of construction vehicles and machinery;
Stockpiling areas;
Directional drilling for construction of the proposed submarine outfall; and
Seabed dredging for the installation of the outfall diffuser.
Operation Phase
During the operation phase of the Project, potential impacts will result from the following:
Operation of the whole sewerage system (including SPSs, STW and outfall pipe) and
emergency overflow of untreated sewage from the trunk sewerage and STW
10.6.6 Magnitude of Landscape Change
The tree survey results are one of the factors by which the magnitude of change from
landscape impacts on LCAs and LRs are assessed, as mentioned in the methodology (Section
10.6.1). Therefore the survey results are indicated on Figure 10.6.5 and given below for each
proposed built structure and the landscape impacts on the LCAs and LRs are then described
in full. At the end of this Section, Table 10.4 summarises the magnitude of change for each
LCA and LR.
Tree Survey Results
The tree survey recorded the following information from the proposed project sites which
will be considered when assessing the magnitude of change for LRs and LCAs which are
described afterwards.
Shui Hau Trunk SPS. Estimated approximately 20 – 25 trees are located at this site,
with DBH range 20 – 40 cm and a height range of 3 – 5 m. The dominant species are
the trees Celtis sinensis, Ficus hispida, Microcos paniculata, Sapium sebiferum and the
shrub species Callicarpa formosana.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-13 B&V / ERM
Tong Fuk Trunk SPS. Estimated approximately 10 trees are located at this site, with
DBH range 30 – 60 cm and a height range of 3 – 9 m. The dominant tree species are
Acacia confusa (on average 9 m high with 30 cm DBH), Ficus hispida, Microcos
paniculata, and Sapium sebiferum.
Cheung Fu Street Trunk SPS. Estimated approximately 25 trees are located at this
site, with DBH range 20 – 70 cm and a height range of 4 – 14 m. The dominant tree
species are Ficus hispida, Mallotus paniculatus, Pinus massoniana, Dimocarpus
longan, Delonix regia (14 m high, 60 cm DBH), Macaranga tanarius, Bauhinia spp.,
Melia azedarach, Schefflera heptaphylla, Aleurites moluccana (15 m high, 70 cm
DBH), Bambusa sp. as well as the shrub species Ixora chinensis and Carmona
microphylla.
Cheung Sha Trunk SPS. Estimated approximately 5 large trees (including one dead
tree) are located at this site, with DBH range 30-60 cm and height range of 6-12 m.
The dominant tree species are Celtis sinensis (12 m high, 50 cm DBH), Dimocarpus
longan (6 - 10 m high, 30 - 60 cm DBH) and Bambusa sp.
San Shek Wan Trunk SPS (both the currently proposed and alternative sties).
Estimated approximately 70-80 trees are located at both these sites, spread fairly
evenly. They are estimated to have DBH range 15 – 80 cm and a height range of 8 – 12
m. The dominant tree species are Microcos paniculata, Lophostemon confertus, Acacia
confusa, Dimocarpus longan, Alangium chinense, Mallotus paniculatus, Litsea cubeba,
Bambusa sp. and shrub species Litsea rotundifolia, Psychotria asiatica,
Eleutherococcus trifoliatus, Severinia buxifolia, Rhapis excelsa, Zanthoxylum nitidum
and herb species Panicum brevifolium are also recorded.
Pui O Trunk SPS. Estimated approximately 60 – 65 trees are located at this site, with
DBH range 15 – 50 cm and a height range of 3 – 6 m. The dominant tree species are
Celtis sinensis, Acacia confusa, Litsea glutinosa, and shrub species Pandanus tectorius,
Murraya paniculata, Sageretia thea are also recorded.
San Shek Wan STW. Estimated approximately 200 trees are located at this site, with
DBH range 20 – 50 cm and a height range of 5 – 8 m. The dominant tree species are
Acacia confusa, Daphniphyllum calycinum, Mallotus paniculatus, Lophostemon
confertus and Ficus hispida.
With regard to LCAs and LRs, Figure 10.6.5 illustrates potential impacts and Table 10.3
summarises the impact from each SPS/STW as well as from the associated pipe works (trunk
sewers, rising mains, and outfall pipe) on the various LCAs and LRs, and further details are
then provided below.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-14 B&V / ERM
Table 10.3 – Impact of SPS/STW and Pipe Works on Various LRs and LCAs Area affected by Project (ha) [sq. m for SPS/STW, m for trunk sewers/ rising mains]
SPS/STW LR1 LR2 LR3 LR4 LR5 LR6 LR7 LR8 LR9 LR10 LCA1 LCA2 LCA4
Proposed Shui Hau Trunk SPS 0.10 0.01 0.11
Proposed Tong Fuk Trunk SPS 0.04 0.02 0.06
Proposed Cheung Fu Street
Trunk SPS 0.08 0.08
Proposed Cheung Sha Trunk SPS 0.03 0.01 0.04
Proposed San Shek Wan Trunk
SPS (Current Option / Alternative
Option)
0.14/
0.17
0.00[20 m2] /
0.00[20 m2] 0.14/ 0.17
Proposed Pui O Trunk SPS 0.15 0.03 0.18
Proposed San Shek Wan STW 0.38 0.01 0.17 0.56
Subtotal for SPS/STW
0.52/
0.55 0.04 0.26 0.03 0.29 0.02 1.17/ 1.20
Pipe works (m) LR1 LR2 LR3 LR4 LR5 LR6 LR7 LR8 LR9 LR10 LCA1 LCA2 LCA4
Trunk Sewers 275 670 875 30 20,180 30 50 170 920 21,500
Rising Mains 40 190 6,900 2,400 2,700
Outfall Pipe 310 10 15 1050 200 120 1100
Subtotal for Pipe works 275 1,020 1,075 30 27,080 30 15 50 1,050 170 3,520 24,320 1100
Note: LR1 Woodland; LR2 Shrubland; LR3 Plantation; LR4 Agricultural Land; LR5 Urban / Village Area; LR6 Stream / Channel; LR7 Rocky Shoreline; LR8 Sandy Beach; LR9
Seascape; LR10 Marsh / Estuarine
LCA1 South Lantau Coastal Uplands and Hillsides; LCA2 South Lantau Coastal Settled Valleys; LCA3 Shui Hau Wan Intertidal Coast (not affected); LCA4 South Lantau Bay
Landscape
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-15 B&V / ERM
LCAs
The SPSs and STW fall within just one LCA, the South Lantau Coastal Settled Valleys
(LCA2) and will affect the LCA during both construction and operation. The pipe works
related to the proposed sewers and rising mains affect two LCAs, LCA2 as well as LCA1,
South Lantau Coastal Uplands and Hillsidess. The outfall pipe mainly affects these same two
LCAs. It is considered that the pipe works associated with the Project will only cause
landscape impacts during construction since the trenches will be backfilled and land
reinstated at operation. Further details on assessing the magnitude of change are given below:
LCA1 South Lantau Coastal Uplands and Hillsides. Approximately 3.5 km of the
pipe works associated with the Project fall on this LCA, principally on the roads within
the LCA where there will be little effect. The majority of the pipes (~2.4 km) are rising
mains (100 mm to 200 mm diameter ductile iron pipes), approximately 200 m of the
outfall pipe passes through this LCA and the remainder are sewage pipes (225mm to
300 mm diameter gravity sewers, or 300 m to 500 m diameter vitrified clay pipes/
concrete pipes for the trunk sewers) (See Figure 10.6.5). Apart from the short section
of outfall pipe, all these pipes will be underneath South Lantau and Chi Ma Wan Road
and at construction there will be some excavation for pipe laying and backfilling work
to reinstate the road. The construction work is not expected to affect the high quality,
highly vegetated and relatively mature scrubland, woodland and some patches of
plantation of this LCA but will be carried out in sections and traffic flow maintained.
Considering the LCA as a whole, during construction the magnitude of change is
considered small. At operation, the roads will have been reinstated with the pipes
beneath and the magnitude of change is considered negligible.
LCA 2 South Lantau Coastal Settled Valleys. The buildings of this Project affect
scattered areas of this LCA (See Figure 10.6.5), while just less than 25 km of the pipe
works fall within it. In total about 1.17/ 1.20 ha of the total 392.47 ha of LCA2 found in
the Study Area is affected by the buildings, and the affected area are considered to be of
lower quality. Approximately 400 trees with DBH range of 15 – 80cm and height range
of 3 – 14m of varying maturity and quality will be affected. This LCA already
accommodates low-rise residential areas and development and given that the proposed
structures are mainly small and all low rise, the Project is compatible with this LCA.
During the construction phase, sections of the South Lantau and Chi Ma Wan Road and
alleys/lanes within the villages will need to be dug up for the construction of the sewers
and rising mains and the landscape impact will increase slightly but this will be a
reversible impact as roads will be reinstated with the pipes beneath at operation.
Overall there will be very little impact on LCA2 and the magnitude of change is
considered small during both construction and operation.
LCA 3 Shui Hau Wan Intertidal Coast. This LCA will not be affected by the Project
and therefore during construction and at operation magnitude of change is negligible.
LCA 4 South Lantau Bay Landscape. Approximately 1,100 m of the outfall pipe
falls within this LCA. To minimize dredging in Pui O Bay, the submarine outfall pipe
will be constructed by Horizontal Directional Drilling (HDD) method from the STW
and only minor dredging of the seabed will be required for the installation of the
diffuser during construction. The area affected is of high quality and relatively mature.
Overall the magnitude of change during construction is considered small and at
operation is considered negligible.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-16 B&V / ERM
LRs
Although ten LRs are found in the Study Area, only five are affected by the SPSs and STW.
The pipe works related to the proposed sewers and rising mains affect eight LRs in total and
the outfall pipe affects four LRs.
LR1 Woodland. This LR is affected by the San Shek Wan SPS and San Shek Wan
STW of the Project (See Figure 10.6.5), and a stretch of approximately 275 m of South
Lantau Road near the proposed Cheung Sha Trunk SPS with woodland to the south will
be affected by both rising mains and trunk sewers which will be laid next to the road.
Approximately 270 – 280 trees with DBH range of 15 – 80cm and height range of 5 –
12m of varying maturity and quality will be affected. The construction work is not
expected to affect the overall high quality vegetation of this LR. During construction
trees along this stretch of road may be felled for the installation of the pipe works.
However only a very small fraction of this LR within the Study Area will be affected
by the Project (See Table 10.3) and overall at construction the magnitude of change is
considered small. During operation, the land will have been reinstated, but the trees
will still be lost and therefore the magnitude of change at operation will remain small.
LR2 Scrubland. A very small area of this LR is affected by SPS/STW buildings (See
Figure 10.6.5), both absolutely (0.01 ha) and relative to the quantity found within the
Study Area (See Table 10.3). The Proposed Tong Fuk Trunk SPS is the building
causing the impact and most of the trees affected by this building are of medium quality
and actually found in land designated as LR6. In addition, approximately 1000 m of
the pipe works are aligned on land classified as shrubland but the majority of this is the
land section of the outlet pipe leading from the STW which will be laid by directional
drilling and not affect the land on top. A short length (about 40 m) is affected by where
both rising mains and sewers will be laid to the west of the proposed Tong Fuk Trunk
SPS under the land and a footpath constructed above and otherwise very small general
areas of scrubland adjacent to villages are affected where village sewers will be laid.
Overall during construction a relatively small area of this LR will be affected by the
Project buildings and pipe works and the magnitude of change is considered small. At
operation, the areas affected by pipeworks will have been reinstated, but the vegetation
will still have been cleared and the proposed Tong Fuk SPS will remain, therefore
magnitude of change will remain small.
LR3 Plantation. A total of 0.26 ha of this LR is affected by the SPSs/STW (See
Figure 10.6.5). The proposed San Shek Wan STW is the main cause of the impact on
this LR although the proposed Trunk SPSs at Shui Hau, Cheung Fu Street, San Shek
Wan, and Pui O also affect it. Approximately 80 - 90 trees with DBH range of 15 –
50cm and height range of 3 – 6m of varying maturity and quality will be affected. In
addition, plantation of medium quality found along some of South Lantau and Chi Ma
Wan Road is close to the works area for construction of the trunk sewers/ rising mains
and approximately 1,075 m of pipe work is calculated to affect this LR, but in reality it
is likely that only the plantation to the west of the proposed Pui O Trunk SPS will
affected by the excavation of the trench to house pipes leading to the SPS from the
nearby road (about 40 m) and will be covered over at operation by the proposed access
to the SPS. To the east of this SPS the pipes will be laid by trenchless method and the
land above will not be affected. It is unlikely tree along the roads will be affected.
Given the number of trees affected at the building sites however, despite a relatively
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-17 B&V / ERM
small area being impacted, the magnitude of change is considered intermediate at
construction and operation.
LR4 Agricultural Land. Of the 5.65 ha of this LR in the Study Area, 0.03 ha of
medium landscape quality will be affected by the buildings in the Project at the
Proposed Cheung Sha Trunk SPS (See Figure 10.6.5). Approximately 5 trees with
DBH range of 30 - 60cm and height range of 6 – 12m of varying maturity and quality
will be affected. In addition, a very small section of sewers (about 30 m) will fall
across some agricultural land just north of the STW and will be laid by trench method
underground here, with a footpath constructed above. Although the Project is not
compatible with this LR, given the very small area and the potential reversibility of the
land affected by the pipe works, the magnitude of change at construction and operation
is considered small.
LR5 Urban/Village Area. Of the 98.62 ha of LR5 found in the Study Area, only 0.29
ha of this LR with low to medium landscape quality is affected by the SPS/STW
structures of the Project (See Figure 10.6.5). Approximately 25 trees with DBH range
of 20 – 70cm and height range of 4 – 14m of varying maturity and quality will be
affected. In addition, during construction, a larger area will be affected as roads and
alley/roads in the villages, with fall within this LR will be excavated to lay just over
27 km of trunk sewers and rising mains. Few trees are found in this LR and are not
considered to affect the magnitude of change. During construction, given the
excavation works to lay pipes, the project is considered to have low compatibility with
this LR and the magnitude of change, at worst, will be intermediate. At operation
however, most of the impact experienced during construction will have gone as the land
with pipes underneath will have been reinstated and the Project is considered
compatible with this LR. Therefore at operation the magnitude of change is considered
small.
LR6 Stream/ Channel. This high quality LR is not affected by any buildings of the
Project, and although the sewer pipe alignment around Ham Tin looks to cross the
stream flowing out from Pui O and Ham Tin, the crossing will use existing manholes
and will not affect the stream. Overall the magnitude of change during construction
and operation is considered negligible.
LR7 Rocky Shoreline. This good quality LR is not affected by any buildings of the
Project. Approximately 15 m of the outfall pipe will pass underneath it and will be
constructed by Horizontal Directional Drilling (HDD) and at operation the land is not
considered to be affected. The magnitude of change during construction and at
operation is considered negligible.
LR8 Sandy Beach. This good quality LR is not affected by any buildings of the
Project, but approximately 50 m of sewers will be laid near the Cheung Sha beach.
Overall the the magnitude of change at construction is considered small but by
operation the land will have been reinstated and the magnitude of change is considered
negligible.
LR9 Seascape. This good quality and mature LR is not affected by any buildings of
the Project or the sewers or rising mains, but the submarine outfall pipe leads out
approximately 1100m into Pui O Bay, To minimize dredging in Pui O Bay. The
seascape in this area has no significant characteristics such as rock formations etc. It is
abundant and of low rarity. To minimize dredging in Pui O Bay, the submarine outfall
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-18 B&V / ERM
pipe will be constructed by Horizontal Directional Drilling (HDD) method from the
STW and only minor dredging of the seabed will be required for the installation of the
diffuser during construction. Overall the magnitude of change during construction is
considered small and at operation is considered negligible.
LR10 Marsh / Estuarine. A very small area of this good quality LR is affected both
absolutely (0.02 ha) (See Figure 10.6.5) and relative to the quantity found within the
Study Area (24.29 ha). The Proposed Tong Fuk Trunk SPS is the cause of impact and
as detailed in the tree survey results an estimated 10 trees with DBH range 30 – 60 cm
and a height range of 3 – 9 m with varying quality and maturity will be affected. The
area of this LR at Tong Fuk will be also affected by installation of approximately
130 m of sewer pieps at construction but these will fall along an existing footpath and
during operation the footpath will be reinstated. Near Ham Tin, about 40 m of sewers
towards the proposed Pui O Trunk SPS are laid underneath a marsh area, but these
sewers will be laid by trenchless method making use of existing manholes and will not
affect the LR here. Overall the magnitude of change during construction is
considered small and at operation is considered negligible.
The magnitude of change for each LCA and LR is summarised in Table 10.4 below.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-19 B&V / ERM
Table 10.4 – Magnitude of Landscape Change *Note: n/a = not applicable
Total
within
Study
Area
(ha)
Affected by
Proposed Built
Structures
including access
roads (ha)
Affected by
Proposed Pipe
Works
(including
Sewers and
Rising Mains)
[length in m]
Compatibility
of Project
(Construction/
Operation)
(Good / Fair /
Low)
Duration of
Impacts
(Construction/
Operation)
Reversibility
of Change
(Construction
/ Operation)
Magnitude of Change
(Negligible / Small /
Intermediate / Large)
ID Description Construction Operation
LCA 1
South Lantau Coastal
Uplands and Hillsides 927.25 Not affected 3,520 Fair / Good Temporary/ n/a Reversible/ n/a Small Negligible
LCA 2
South Lantau Coastal Settled
Valleys 392.47 1.17/ 1.20 24,320 Fair / Good
Mainly
Temporary/
Permanent
Partly
reversible/
Irreversible Small Small
LCA 3
Shui Hau Wan Intertidal
Coast 20.62 Not affected Not affected Good / Good n/a n/a Negligible Negligible
LCA 4 South Lantau Bay Landscape 371.14 Not affected 1,100 Good/ Good Temporary/ n/a Reversible/ n/a Small Negligible
LR 1 Woodland 311.47 0.52/0.55 275 Fair/ Fair
Mainly
Temporary/
Permanent
Partly
reversible/
Irreversible
Small Small
LR 2 Scrubland 689.49 0.04 1,020 Low/Low
Mainly
Temporary/
Permanent
Partly
reversible/
Irreversible Small Small
LR 3 Plantation 163.04 0.26 1,075 Low/Low
Mainly
Temporary/
Permanent
Partly
reversible/
Irreversible Intermediate Intermediate
LR 4 Agricultural Land 5.65 0.03 30 Low/Low
Mainly
Temporary/
Permanent
Partly
reversible/
Irreversible Small Small
LR 5 Urban/ Village Area 98.62 0.29 27,080 Low/Good
Mainly
Temporary/
Permanent
Largely
reversible/
Irreversible Intermediate Small
LR 6 Stream/ Channels 15.22 Not affected 30 Good / Good n/a n/a Negligible Negligible
LR 7 Rocky Shoreline 3.95 Not affected 15 Good / Good n/a n/a Negligible Negligible
LR 8 Sandy Beach 31.04 Not affected 50 Low / Good Temporary/ n/a Reversible/ n/a Small Negligible
LR 9 Seascape 368.72 Not affected 1,050 Fair / Good Temporary/ n/a Reversible/ n/a Small Negligible
LR10 Marsh/ Estuarine 24.29 0.02 170 Low/Low
Mainly
Temporary/ n/a
Partly
Reversible/ n/a Small Negligible
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-20 B&V / ERM
10.6.7 Significance of Landscape Impacts
The significance of the landscape impacts is a product of the magnitude of the change caused
by the Project and the sensitivity of the LCA/LR as shown in Table 10.2.
Sections 10.6.2 and 10.6.3 describe the sensitivity of each LCA/LR identified while Section
10.6.6 described the magnitude of change experienced by each LCA/LR and this is
summaries in Table 10.4.
Table 10.6 goes on to show the significance of landscape impacts as a produce of these
values, according to Table 10.2. It shows the resulting impact significance both before
mitigation, as well as listing appropriate mitigation measures for each LCA/LR and then
giving the resulting residual landscape impacts.
10.6.8 Mitigation Measures
Mitigation measures are proposed, as appropriate, to reduce potential landscape impacts as
outlined below. In reality many of these measures will also serve as visual mitigation
measures (e.g. compensatory planting can both compensate for trees lost as well as provide
visual greening or screening for Visual Sensitive Receivers (VSRs)) and therefore landscape
and visual mitigation measures have been grouped and are referenced as appropriate in the
LIA and VIA sections.
Mitigation measures follow the principle of the mitigation pyramid, which is firstly to
undertake all means to avoid impacts, then reduce any unavoidable impacts to as low as
practicable and finally to mitigate any remaining impacts.
Mitigation measures are proposed to be considered during design, construction and operation.
Mitigation measures can be relevant to both construction and operation phases of the Project.
For example detailed design measures will be implemented during construction but will aim
to reduce both construction and operation impacts.
Most measures should be considered at or before the construction stage of the Project. All
planting should follow a Detailed Landscape Design and Planting Plan which must be
approved with the relevant departments as part of the detailed design. This will include
details of tree transplantation and compensatory tree planting (MM4 and MM5 in Table 10.5
below). For the purposes of this assessment, a Master Layout Plan indicating landscaping
mitigation planting is provided in Figure 10.6.6 with further detail in Figures 10.6.6 a-g.
Agreement has been sought with relevant agencies responsible for funding, implementation,
management and maintenance, and are listed under Table 10.5 against the proposed
mitigation measures. In addition it is understood that ‘good site practices’ will be undertaken
during construction, including keeping the construction sites in good order, having an
effective waste managementpland and considering ProPECC PN1/94 Construction Site
Drainage as necessary.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-21 B&V / ERM
Table 10.5 – Proposed Mitigation Measures for Landscape and Visual Impacts
ID
No.
Mitigation Measure Funding Agency Implementation
Agency
Management/
Maintenance
Agency
MM
1
Detailed Design Considerations – detailed design of development components should reduce
landscape footprint and visibility of structures and blend with the existing environment as far as
possible.
Temporary structures and construction works should be planned with care to minimise
disturbance to trees/ vegetation, topography and existing built structures. The footprint of the
proposed facilities shall be compressed to a practical minimum taking into account functional,
operational and maintenance needs so as to cause minimum land conversion impact.
Where technically feasible design should aim to reduce the visibility of the proposed above
ground structures. This will include massing and building height considerations. In addition the
form, textures, finishes and colours of the proposed structures should be as compatible with the
existing surroundings as far as possible. Light earthy tone colours such as shades of green, shades
of grey, shades of brown and off-white may be utilised where technically feasible to reduce the
visibility of the new development components, including all SPSs and the STW. To further
improve visual amenity, natural building materials such as stone and timber, should be preferably
adopted for architectural features, where technically feasible. To date, a variety of materials are
proposed for façade treatment to create a layering effect that breaks down the massing of
structures. Translucent materials and louvers shall be used to enhance the permeability of the
buildings.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
-
Operation Phase
DSD
-
DSD
MM
2
Vertical Greening and Green Roof – Provide vertical greening to soften hard surfaces, and roof
greening to enhance landscape and visual quality.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
-
Operation Phase
DSD
-
DSD (1)
MM
3
Tree Protection and Preservation – Trees/ woodland within the Project Site will be protected
and preserved as far as possible in accordance with DEVB TC(W) No. 7/2015 .
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
DSD / Contractor
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-22 B&V / ERM
ID
No.
Mitigation Measure Funding Agency Implementation
Agency
Management/
Maintenance
Agency
MM
4
Tree Transplantation – Should removal of trees be unavoidable due to construction impacts,
trees will be transplanted or felled according to Clause 3.97 of the General Specification of Civil
Engineering Works – Section 3 Landscape Softworks and Establishment Works. Transplantation
must be carried out prior to site formation works and be treated with establishment works
immediately after transplanting, for a period of no less than 12 months.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
Contractor / DSD
Operation Phase
DSD
-
DSD (1)
MM
5
Compensatory Tree Planting - Where loss of existing trees is unavoidable, compensatory
planting of trees should be provided in accordance with DEVB TC(W) No. 7/2015 to compensate
for those trees felled. Complete compensatory planting at least 3-6 months before construction
completion, followed by 12 months establishment period after construction completion.
The selection of planting species shall be made with reference to the species identified in the Tree
Survey and preferably be native to Hong Kong or the South China region. As stated in DEVB
TC(W) No. 7/2015, as far as possible, implementation of compensatory planting should be of a
ratio not less than 1:1 in terms of quality and quantity within the site, i.e. the total numbers and
the aggregated girth size of compensatory trees within the site and off-site, should not be less than
that of the tree(s) to be felled. In addition, the quality of compensatory trees should be at least of
“heavy standard” and further details regarding soil specification and ground surface treatment of
recipient locations of the compensatory tree will be provided in a Detailed Landscape Design and
Planting Plan which should detail the location of compensatory planting.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
Contractor
Operation Phase
DSD
-
DSD (1)
MM
6
Buffer Planting – Tall screen/buffer trees and shrubs shall be planted to screen the proposed built
structures. This measure may additionally form part of the compensatory planting (MM5) and
will improve compatibility with the surrounding environment.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
Contractor
Operation Phase
DSD
-
DSD (1)
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ID
No.
Mitigation Measure Funding Agency Implementation
Agency
Management/
Maintenance
Agency
MM
7
Topsoil reuse – Excavated topsoil should be stripped and stored for re-use in the construction of
the soft landscape works of this Project or other projects. This is considered a general measure for
good site practice.
Design Phase
DSD
DSD
-
Construction Phase
DSD
DSD/ Contractor
DSD
MM
8
Light Control – Control of night time lighting glare shall be implemented to minimize glare
impact to adjacent VSRs during construction, and operation as necessary.
Design Phase
DSD
-
DSD
Construction Phase
DSD
DSD/ Contractor
-
Operation Phase
DSD
-
DSD
1. Before handover to the final designated management and maintenance agents, DSD shall be responsible for the management and maintenance of all soft landscaping.
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10.6.9 LIA Outcome
Given the proper implementation of the suggested mitigation measures, the Project is
expected to have insignificant residual operation landscape impacts by year 10, as
summarized in Table 10.6.
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Table 10.6 – Significance of Landscape Impacts ID
Landscape
Resource/
Landscape
Character
Area
Sensitivity
(Low,
Medium,
High)
Magnitude of Change
BEFORE Mitigation
(Negligible, Small,
Intermediate, Large)
Impact Significance
BEFORE Mitigation
(Insignificant, Slight,
Moderate, Substantial)
Recommended Mitigation
Measures (General good
practice measures e.g. MM7
Topsoil reuse) are not
included for specific LCAs/
LRs)
Residual Impact Significance UPON
Mitigation
(Insignificant, Slight, Moderate, Substantial
Construction Operation Construction Operation Construction Operation Construction Operation
Day 1
Operation
Year 10
LCA1 South Lantau
Coastal
Uplands and
Hillsides
Landscape
High Small Negligible Moderate Insignificant MM1, MM3,
MM4, MM5
n/a Slight Insignificant Insignificant
LCA2 South Lantau
Coastal Settled
Valleys
Landscape
Medium Small Small Slight Slight MM1, MM2,
MM3, MM4,
MM5
MM1, MM2,
MM3, MM4,
MM5
Insignificant Insignificant Insignificant
LCA3 Shui Hau Wan
Intertidal Coast
Landscape
High Negligible Negligible Insignificant Insignificant n/a n/a Insignificant Insignificant Insignificant
LCA4 South Lantau
Bay Landscape
High Small Negligible Moderate Insignificant n/a n/a Moderate Insignificant Insignificant
LR1 Woodland High Small Small Moderate Moderate MM1, MM3,
MM4, MM5
MM1, MM3,
MM4, MM5
Moderate Moderate Slight
LR2 Scrubland Medium Small Small Slight Slight MM1, MM3,
MM4, MM5
MM1, MM3,
MM4, MM5
Slight Insignificant Insignificant
LR3 Plantation Medium Intermediate Intermediat
e
Moderate Moderate MM1, MM3,
MM4, MM5
MM1, MM3,
MM4, MM5
Slight Slight Insignificant
LR4 Agricultural
Land
Medium Small Small Slight Slight MM1, MM3,
MM4, MM5
MM1, MM3,
MM4, MM5
Slight Slight Insignificant
LR5 Urban/ Village
Area
Medium Intermediate Small Moderate Slight MM1, MM3,
MM4, MM5
MM1, MM3,
MM4, MM5
Moderate Slight Insignificant
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ID
Landscape
Resource/
Landscape
Character
Area
Sensitivity
(Low,
Medium,
High)
Magnitude of Change
BEFORE Mitigation
(Negligible, Small,
Intermediate, Large)
Impact Significance
BEFORE Mitigation
(Insignificant, Slight,
Moderate, Substantial)
Recommended Mitigation
Measures (General good
practice measures e.g. MM7
Topsoil reuse) are not
included for specific LCAs/
LRs)
Residual Impact Significance UPON
Mitigation
(Insignificant, Slight, Moderate, Substantial
Construction Operation Construction Operation Construction Operation Construction Operation
Day 1
Operation
Year 10
LR6 Stream/
Channels
High Negligible Negligible Insignificant Insignificant n/a n/a Insignificant Insignificant Insignificant
LR7 Rocky
Shoreline
High Negligible Negligible Insignificant Insignificant n/a n/a Insignificant Insignificant Insignificant
LR8 Sandy Beach High Small Negligible Moderate Insignificant n/a n/a Moderate Insignificant Insignificant
LR9 Seascape Medium Small Negligible Slight Insignificant Good site
practice
n/a Slight Insignificant Insignificant
LR10 Marsh/
Estuarine
High Small Negligible Moderate Insignificant MM1, Good
site practice
MM1 Moderate Insignificant Insignificant
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10.7 Visual Impact Assessment
10.7.1 Methodology
In accordance with Annex 18 of the EIAO-TM the Visual Impact Assessment (VIA) analyses
the potential visual impacts of the Project and as also required in EIA Study Brief. It is
evaluated by an understanding of the existing visual qualities within the region that can be
visually affected by a development. In this report, the area that can be visually affected is
referred to as the visual envelope and, as stipulated in the Study Brief No. ESB-209/2009,
forms the visual impact assessment area. The impact assessment has been conducted with
respect to the existing views and visual amenity of the site and the representative Visual
Sensitive Receivers (VSRs) identified within the visual envelope. The VIA covers the
following tasks:
Identification of the Visual Envelope. Geographical Information System (GIS)
software was utilised to determine areas that could potentially see the development
during construction and operation (See Figure 10.7.1). This GIS visual envelope
analysis was based solely on topography and dimensions of the potential new
structures, and did not take into account the screening potential of vegetation, which
further reduces the actual visual envelope. Further to the GIS visual envelope analysis,
the study of aerial maps and site visits helped to establish locations that could and could
not see the Project taking into account factors other than topography.
The visual envelope is calculated assuming good visibility ( 4 )
but in reality many
climatic conditions result in changes to visibility. For example, sea haze, cloud cover
and rainfall can all alter the visibility of the Project. Sea haze is a climatic condition
along coastlines that can reduce visibility even on days when the weather is fine; cloud
cover can change no matter how reflective elements of a development are and alter the
contrast with their surroundings; and rainfall reduces visibility as the water droplets
obscure vision. The diminution of visual clarity brought about by atmospheric
conditions also increases with distance.
Identification of VSRs and Vantage Points (VPs) within the Visual Envelope.
VSRs are people who would reside, play, work or travel in or through the visual
envelope. VSRs’ views were studied through desktop analysis and on-site inspection.
Key locations, Vantage Points (VPs), were also selected to further analyse the visual
impact of the Project through the use of photomontages. The VPs are selected to
represent worst case scenarios, due to their proximity to or elevated view of the Project
site. The photomontages provide a comparison between existing views, proposals after
completion without mitigation measures and with mitigation measures. VSRs can be
categorised by type, as classified below.
Assessment of the sensitivity of VSRs. Factors considered include the type of VSR,
value and quality of existing views, availability and amenity of alternative views, type
and estimated number of receiver population, duration or frequency of view, and degree
of visibility. Type of VSR is classified according to whether a person is at home, at
work, at play, or travelling.
(4) The Hong Kong Observatory defines ‘reduced visibility’ criteria as ‘visibility below 8 km, relative humidity below 95%, no fog, mist, or
precipitation (See http://www.weather.gov.hk/cis/statistic/hka_redvis_statistic_e.htm, Accessed 28 October 2016) and hence ‘good visibility’ has
been defined as visibility of 8 km or over, when relative humidity is below 95 % and there is no rain, mist or fog.
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Those who view the impact from homes are considered to be highly sensitive as the
character of view from their home will have a substantial effect on their perception of
quality and acceptability of their home environment and their general quality of life.
These VSRs are termed ‘Residential’ VSRs (H) and are generally highly sensitive to
change.
Those who view the impact from their workplace are considered to be relatively less
sensitive as the character of view. The view is considered to have a less important
effect on their perception of quality of life, particularly if working in industrial sites or
open storage areas. These VSRs are termed ‘Industrial’ VSRs (I) and are considered to
be less sensitive to change than residential VSRs.
Those who view the impact while engaging in outdoor recreational activities such as
hiking or relaxing in open outdoor spaces or on the beach may display varying
sensitivity depending on the type of activity they normally undertake. These VSRs are
termed ‘Recreational’ VSRs (R).
Those who view the impact while travelling in public/private vehicles or on foot will
display varying sensitivity depending on the speed, nature and frequency of travel.
These VSRs are termed ‘Travelling’ VSRs (T) and generally have the lowest sensitivity
to change.
It should be noted that the above only provides guidance and each VSR has been
assessed according to its specific circumstances. The sensitivity of each VSRs is
classified as follows:
(a) High: The VSR is highly sensitive to any change in their viewing experience;
(b) Medium: The VSR is moderately sensitive to any change in their viewing
experience; and
(c) Low: The VSR is only slightly sensitive to any change in their viewing experience.
Identification of potential sources of visual impacts. The various elements of the
construction and operation works that have the potential to cause visual impacts were
identified and are noted.
Identification of the magnitude of visual change. The magnitude of visual change
depends on a number of factors including the compatibility of the Project with the
surrounding landscape, duration of impacts during construction and operaion phase,
scale of development, reversibility of the impact, distance of the source of impact from
the viewer, degree of visibility of the impact and potential blockage of view. The
magnitude of visual change is classified as follows:
(a) Large: The VSRs will experience a major change in the character of their existing views.
(b) Intermediate: The VSRs will experience a moderate change in the character of their existing views.
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(c) Small: The VSRs will experience a small change in the character of their existing views.
(d) Negligible: The VSRs will experience no discernible change in the character of their existing views.
Recommendation of the potential visual mitigation measures and implementation
programme. These may take the form of adopting alternative designs or revisions to
the basic engineering and architectural design to prevent and/ or reduce adverse
impacts, remedial measures such as colour and textural treatment of built structures and
greening of those structures; and compensatory measures such as tree planting. A table
of proposed mitigation measures and implementation programme (where necessary) is
provided with the suggested agencies responsible for their funding, implementation and
management/ maintenance identified.
Prediction of the significance thresholds of visual impacts before and after the
implementation of mitigation measures. By assessing the magnitude of the various
impacts and the sensitivity of VSRs, the degree of significance of the impacts are
categorised in a logical, well-reasoned and consistent manner. Table 10.2 shows the
rationale for dividing the degree of significance into four thresholds, namely,
Insignificant, Slight, Moderate and Substantial, depending on the combination of a
negligible-small-intermediate-large magnitude of change and a low-medium-high
degree of sensitivity of VSRs. The significant thresholds are defined as follows:
(a) Substantial: Adverse/beneficial impact where the Project will cause substantial
deterioration or improvement in existing visual quality.
(b) Moderate: Adverse/beneficial impact where the Project will cause a noticeable
deterioration or improvement in existing visual quality.
(c) Slight: Adverse/beneficial impact where the Project will cause a barely perceptible
deterioration or improvement in existing visual quality.
(d) Insignificant: The impact will cause no discernible change in the existing visual
quality.
In order to help illustrate the visual impacts of the development, photomontages have
been prepared from selected VPs, which compare the existing conditions with the view
after construction of the proposed Project.
Prediction of Acceptability of Impacts. An overall assessment of the acceptability, or
otherwise, of the impacts has been carried out to determine whether the visual impacts
are beneficial, acceptable, acceptable with mitigation measures, unacceptable or
undetermined, in accordance with the requirements of Annex 10 of the EIAO-TM.
10.7.2 Baseline Visual Characters
The general baseline visual character of the Project Site is a coastal area, with limited
development at the base of green sloping peaks of Lantau Island. A large stretch of the
coastline is sandy beaches, many of which are gazetted and frequented by recreational users.
There is one principal two-lane road running through the Project site connecting the few
villages which are made up of low-rise houses, typically three stories high. Other buildings
along the coast are generally low-rise and residential, including a number of villas around
Cheung Sha, but there is also the Tong Fuk Correctional Institution near Tong Fuk, made up
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of a number of larger slightly taller building blocks. Residential/Commercial buildings
spread a limited distance from the shore before the terrain slopes up to the peaks of Lantau
Island. These hillsides have two main trails running along their contours, at lower and higher
levels which are highly vegetated and thus give a green aspect to the whole area. The sea and
bay area is also a distinctive feature of the area. Overall all these elements are combined to
create a fairly natural baseline visual character.
10.7.3 Identification Visually Sensitive Receivers and Vantage Points
A plan of the selected Visually Sensitive Receivers (VSRs) for the assessment are shown in
Figure 10.7.2 along with the selected Vantage Points (VPs) from which photomontages have
been developed to help illustrate the potential visual impacts caused by the Project.
As illustrated, many people within the Study Area fall outside the visual envelope. A number
of viewers fall within the visual envelope and are included as VSRs, but in reality site visits
have shown that their views of the Project components are blocked by natural vegetation or
other buildings. Images in Figure 10.7.3a & b help to illustrate the limited views of these
VSRs. Photomontages in Figures 10.7.5-16 also show how relatively small the SPS
buildings are and how easily they are shielded by exisiting surrounding vegetation (natural or
as part of mitigation measures) or buidlings.
Each VSR assessed in the impact assessment is detailed below and their sensitivity
summarized in Table 10.7. Figures 10.7.4a & 10.7.4b provide illustrative photographs of
each VSR.
VSR H1 – Residents of Shui Hau. This VSR principally represents the residents of
Shui Hau main village area. Although these residents are outside the visual envelope
and cannot see the proposed Shui Hau Trunk SPS site, during construction of the
village sewerage system, the works may be visible to them. This is a small village with
few viewers who would get occasional views of the construction work. The village is
surrounded by greenery with high quality views to the coast and South Lantau uplands.
There are alternative views to that of the alleys and roads where the construction works
will take place, and the Project will only be evident to these residents during
construction. This VSR also includes a couple of isolated houses just outside the main
village area, due east along South Lantau Road and across the road from the proposed
Shui Hau Trunk SPS site. These houses will have a view of the site partly screened by
natural vegetation. There are under five houses here and so very few viewers. Overall
this VSR is considered to have medium sensitivity.
VSR H2 – Residents of Tong Fuk. This VSR includes some residents of Tong Fuk, a
small village which predominantly faces the coast (and hence the proposed Tong Fuk
Trunk SPS). Limited houses along the South Lantau Road and some at higher levels of
the village will have views of the proposed SPS site, while existing buildings or
structures and vegetation will block views from the majority of houses. Some residents
will be able to see the construction of the village sewerage system in the short-term.
Although there are relatively few viewers, the village is surrounded by greenery and
generally has high quality views to the coast and South Lantau uplands and it is
considered to have high sensitivity.
VSR H3 – Residents around Cheung Sha. This VSR includes some residents around
Cheung Sha. Most views to the proposed Cheung Sha Trunk SPS are blocked by
existing vegetation and other buildings and those who may have views, will only have
occasional partial views. Residents will be able to see the construction of the village
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sewerage system in the short-term but no houses are very close to the proposed SPS and
although existing surrounding views are of high quality, there are very few viewers in
this VSR group with views of the SPS that it is considered to have medium sensitivity.
VSR H4 – Residents around San Shek Wan. Views to the proposed San Shek Wan
Trunk SPS for most of the few residents around San Shek Wan are either blocked by
vegetation or existing buildings. Roadside planting along south of South Lantau Road
consists of tall trees on the sloping and therefore the proposed site/ alternative site of
the San Shek Wan SPS at the elevation would only be partially visible to the few
houses with views. Residents will be able to see the construction of the village
sewerage system in the short-term but the proposed SPS will be on the opposite side of
the road to all houses and only one house (Ming Garden) close to the road may get a
better view of the SPS. Although existing surrounding views are of high quality, there
are so few viewers in this VSR group with notable views of the proposed SPS site that
it is considered to have medium sensitivity.
VSR H5 – Residents around Pui O. This VSR includes residents of Pui O Lo Uk
Tsuen, Pui O San Wai, Pui O Lo Wai and surrounding. Many residents will be able to
see the construction of the sewerage system inside the villages in the short-term.
Houses near South Lantau Road mainly face south or southeast and distant from the
San Shek Wan STW and Pui O Trunk SPS. In addition, most views to the the proposed
San Shek Wan STW and Pui O Trunk SPS would be obscured by the existing
vegetaions. Only a few houses at elevated sections of Pui O Lo Uk Tsuen and Pui O
San Wai have partial views west towards the STW. From the higher elevations of the
villages viewers may get partial views of the proposed Pui O Trunk SPS. The existing
quality of views for these residents is of high quality, taking into accoaunt the estuary at
Pui O and the traditional low rise houses of Ham Tin as well as the naturally vegetated
South Lantau uplands. Overall this VSR has high sensitivity.
VSR H6 – Residents around Ham Tin. This VSR includes the few residents of Ham
Tin San Tsuen and Ham Tin Kau Tsuen along Chi Ma Wan Road. These residents will
be able to see the construction of the sewerage system inside the villages in the short-
term. The houses mainly face the coast and the proposed Pui O Trunk SPS, but the SPS
is across the river from these houses and partly blocked by vegetation. Although there
are relatively few viewers, these viewers are surrounded by greenery and generally
have high quality views to the coast and South Lantau uplands and are considered to
have high sensitivity.
VSR H7 –Residents around Cheung Fu Street. This VSR principally considers one
house next to and directly facing the proposed Cheung Fu Street Trunk SPS as well as
another three houses just behind, whose higher floors may have partial views of the
SPS site. It also generally includes residents in this area around Cheung Fu Street and
extends to Leyburn Villas. Residents will be able to see the construction of the village
sewerage system in the short-term. The existing views are of high quality, and this
VSR is considered to have high sensitivity.
VSR H8 – Inmates of Tong Fuk Correction Institution. This VSR includes
residents of Tong Fuk Correction Institution, whose views out will be obscured by the
high perimeter fence and natural vegetations. Views out from this VSR mainly face the
coast to the south, rather than west to Tong Fuk Trunk SPS. This VSR is considered to
have low sensitivity.
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VSR R1 – Hikers on the Lantau Trail. The Lantau trail in this area is largely along a
concrete catchwater with significant planting along the way blocking many views down
to the coast. Further east, the trail has not been paved over and does not follow a
concrete catchwater, but views are still partially blocked by vegetation (See Figure
10.7.3b). This VSR represents all hikers on the Lantau trail or trails at a similar
elevation. They will only have glimpse, transient views to the proposed sites at various
points in their route and their sensitivity is considered to be low.
VSR R2 – Visitors, Beach users and Campers at Cheung Sha. This VSR includes
the visitors who come to Cheung Sha beach and also represents users of the campsite
located in this area as well as visitors to the restaurants. Viewers for this VSR are
mainly looking south out to sea, away from the proposed Cheung Sha Trunk SPS, but
the campers will have a direct view since the SPS site borders the campsite. Existing
views are of high quality but viewers are mainly transient visitor to the area. Their
sensitivity is considered to be medium.
VSR R3 – Hikers on the South Lantau Country Trail & similar. The South Lantau
Country Trail hikers are similar to those represented by R1, with occasional, transient
glimpse views, but this trail is notably higher and hence further from the proposed
Project. This VSR represents all hikers at higher elevations in this area. As their
sensitivity is considered to be relatively lower than those in R1, thus their sensitivity is
still considered to be low.
VSR R4 – Beach users and users of the Football pitch at Pui O. Although the Pui O
Trunk SPS is blocked from view to most Pui O beach users due to the buildings
fronting the beach and vegetation just behind, the proposed San Shek Wan STW site
may be partially visible in the distance. Similarly, users of the football pitch may
partially see the STW but vegetation will block their view to the SPS. Overall, this
VSR is considered to have low sensitivity.
VSR R5 – YWCA users. The YWCA is located at the top of a hill at the bottom of
which the San Shek Wan STW will be located. However, trees line the steep road
down the hill and the surrounding slopes are considered to block any view of the SPS
(See Figure 10.7.3a). Viewers here are recreational and this VSR is considered to have
a low sensitivity.
VSR T1 – Travellers on South Lantau Road. This VSR represents travellers on
South Lantau Road. During construction, the laying of the trunk sewerage system will
be visible to this VSR. Viewers are principally in vehicles, either private cars or public
buses, and their views of some of the proposed SPSs and STW would be partial and
transient. This VSR is considered to have low sensitivity.
VSR T2 – Travellers on Tung Chung Road (old and new). This VSR represents
travellers on both old and new Tung Chung Road, although old Tung Chung Road is
now closed to vehicles and mainly used as a hiking trail. Viewers on the new road are
principally in vehicles, either private cars or public buses, and their views of some of
the proposed SPSs and STW would be partial and transient. This VSR is considered to
have low sensitivity.
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Table 10.7 – VSR Sensitivity ID No. Type of VSR Loction of VSR Number of
Individuals
(Very few, Few,
Many, Very many)
Quality of
Existing View
(Poor/ Fair/
Good)
Availability
of
Alternative
Views
Degree of Visibility
(Glimpse/ Partial/ Full)
Duration of View
(Short/ Medium/
Long)
Frequency of View
(Rare/ Occasional/
Frequent)
Sensitivity
(Low, Medium,
High)
H1 Residential Residents of Shui Hau Few Good Yes Partial Short Rare Medium
H2 Residential Residents of Tong Fuk Few Good Yes Partial Long Occasional High
H3 Residential Residents around Cheung
Sha
Very Few Good Yes Partial Long Occasional Medium
H4 Residential Residents around San
Shek Wan
Few Good Yes Partial Long Occasional Medium
H5 Residential Residents around Pui O Many Good Yes Partial Long Occasional High
H6 Residential Residents around Ham
Tin San Tsuen
Few Good Yes Partial Long Occasional High
H7 Residential Residents around Cheung
Fu Street
Few Good Yes Partial Long Occasional High
H8 Residential Inmates of Tong Fuk
Correction Insitution
Few Fair Yes Not visible Long Rare Low
R1 Recreational Hikers on Lantau Trail Few Good Yes Glimpse Medium Rare Low
R2 Recreational Visitors, Beach users and
Campers at Cheung Sha
Few Good Yes Full Medium Occasional Medium
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ID No. Type of VSR Loction of VSR Number of
Individuals
(Very few, Few,
Many, Very many)
Quality of
Existing View
(Poor/ Fair/
Good)
Availability
of
Alternative
Views
Degree of Visibility
(Glimpse/ Partial/ Full)
Duration of View
(Short/ Medium/
Long)
Frequency of View
(Rare/ Occasional/
Frequent)
Sensitivity
(Low, Medium,
High)
R3 Recreational Hikers on the South
Lantau Country Trail
Few Good Yes Glimpse Medium Rare Low
R4 Recreational Beach users and users of
the Football pitch at Pui O
Few Good Yes Glimpse Medium Occasional Low
R5 Recreational YWCA users Few Good Yes Not visible Medium Occasional Low
T1 Travelling Travellers on South
Lantau Road
Few Good Yes Glimpse Medium Occasional Low
T2 Travelling Travellers on Tung Chung
Road (old and new)
Few Good Yes Glimpse Medium Occasional Low
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10.7.4 Potential Sources of Visual Impact
The potential sources of visual impacts are the same as the sources of landscape impacts
described in Section 10.6.5. Specifically regarding visual impacts, the proposed STW and
SPS are the major visual elements of the proposed development which may visually impact
on the surrounding VSRs.
10.7.5 Magnitude of Visual Change
As the viewer moves further away from the SPSs and STW (the major visual element of the
proposed development) the magnitude of visual change decreases until the structures are no
longer noticeable within the view. The proposed STW and some SPS sites are within close
proximity to residential areas and other inhabited areas next to South Lantau Road but the
sites are also mostly small and snugly fit into nearby land features and are screened from
view by existing vegetation and structures.
Based on the locations of the selected VSRs, VPs have been selected for photomontage
preparation and these help illustrate the possible visual impacts experienced by the range of
VSRs. They support information provided in the text and have been selected to illustrate
representative vantage points which, in combination, give an impression of what the project
will look like in general. Photomontages in are shown in Figures 10.7.5 – 16.
Figures 10.7.5a and 10.7.5b show the view from VP1 (representing VSR R1 Hikers on the
Lantau Trail), the Lantau Trail above Shui Hau Wan in the west of Shui Hau Trunk SPS,
looking north east.
Figures 10.7.6a and 10.7.6b show the view from VP2 (representing VSR T1 Travellers on
South Lantau Road), the South Lantau Road in the west of the Shui Hau Trunk SPS, as it
approaches the proposed Shui Hau Trunk SPS.
Figures 10.7.7a and 10.7.7b show the view from VP3 (representing VSR H2 Residents of
Tong Fuk and VSR T1 Travellers on South Lantau Road), the bus terminal at Tong Fuk.
Figures 10.7.8a and 10.7.8b show the view from VP4 (representing VSR R4 Beach users and
users of the Football pitch at Pui O), on Pui O beach looking northwest.
Figures 10.7.9a and 10.7.9b show the view from VP5, the western edge of Ham Tin, on Chi
Ma Wan Road, representing the residents of Ham Tin area (VSR H6).
Figures 10.7.10a and 10.7.10b show the view from VP6, a distant view over the whole Pui O
area from a trail at lower elevation on Chi Ma Wan peninsular (VSR R1), to give an overall
impression of the changes caused to the area by the largest structure, the STW, as well as
other visible SPS, notably the proposed Pui O Trunk SPS.
Figures 10.7.11a and 10.7.11b show the view from VP7, South Lantau Road (VSR T1) at its
closest point to the proposed San Shek Wan STW.
Figures 10.7.12a and 10.7.12b show the view from VP8, at Cheung Fu Street looking west to
the proposed Cheung Fu Street Trunk SPS, representing VSR H7 Residents around Cheung
Fu Street and T1 Travellers on South Lantau Road.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-36 B&V / ERM
Figures 10.7.13a and 10.7.13b show the view from VP9, camp site at Cheung Sha beach
(VSR R2), looking west to proposed Cheung Sha Trunk SPS and residential area behind to
left (VSR H3).
Figures 10.7.14a and 10.7.14b show the view from VP10, Lantau Trail (VSR R1) looking
south east towards the proposed Pui O Trunk SPS and proposed San Shek Wan STW.
Figures 10.7.15a and 10.7.15b show the view from VP11 (representing H4 Residents around
San Shek Wan) looking towards the proposed San Shek Wan Trunk SPS (Option 1 and 2).
Figures 10.7.16a and 10.7.16b show the view from VP12, (representing H5 Residents around
Pui O) looking towards the proposed San Shek Wan STW.
Taking into account the baseline descriptions for each VSR provided in Section 10.7.2 as
well as the illustrations of the photomontage, the magnitude of change for each VSR is given
in Table 10.8. As for the sewerage works at the villages and the trunk sewers/ rising mains
along South Lantau Road/ Chi Ma Wan Road, the visual impact during constriction phase
would be transient, whilst no visual impact is anticipated during operation phase as the
sewers are underground.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-37 B&V / ERM
Table 10.8 – Magnitude of Visual Change
ID
No.
Type of
VSR
Loction of
VSR
Approx. Min.
Distance between
VSRs and
SPS/STW site (m)
Scale of
Development (1)
Degree of visibility of any SPS, STW,
and/or sewer & rising mains
installation/
Potential Blockage Of View (for the
worst affected viewer)
Compatibility
of Project
(Construction/
Operation) (2)
Duration of
Impacts
(Construction/
Operation)
Reversibility of
Change
(Construction/
Operation)
Magnitude of Change
(Negligible / Small /
Intermediate / Large)
Construction Operation
H1 Residential Residents of
Shui Hau
380 from Village
50 from isolated
houses
Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
SPS partly visible to isolated houses
only/
Relatively small extent of field of
vision.
(See Fig 10.7.5a (VP1) in the vicinity to
help illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
H2 Residential Residents of
Tong Fuk
20 Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
SPS partially visible.
(See Fig 10.7.7a (VP3))
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Intermediate Intermediate
H3 Residential Residents
around
Cheung Sha
50 Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
SPS unlikely to be visible.
(See Fig 10.7.3b and Fig 10.7.13a
(VP9) in the vicinity to help illustrate)
Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
H4 Residential Residents
around San
Shek Wan
40 Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
SPS unlikely to be visible.
(See Fig 10.7.15a (VP11) to help
illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-38 B&V / ERM
ID
No.
Type of
VSR
Loction of
VSR
Approx. Min.
Distance between
VSRs and
SPS/STW site (m)
Scale of
Development (1)
Degree of visibility of any SPS, STW,
and/or sewer & rising mains
installation/
Potential Blockage Of View (for the
worst affected viewer)
Compatibility
of Project
(Construction/
Operation) (2)
Duration of
Impacts
(Construction/
Operation)
Reversibility of
Change
(Construction/
Operation)
Magnitude of Change
(Negligible / Small /
Intermediate / Large)
Construction Operation
H5 Residential Residents
around Pui
O
120 to STW Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
STW onlypartially visible and SPS
unlikely to be visible.
(See Fig 10.7.16a (VP12) to help
illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
H6 Residential Residents
around Ham
Tin San
Tsuen
20 to SPS Small Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.
SPS and STW partially visible.
Relatively small extent of field of
vision.
(See Fig 10.7.9a (VP5) and Fig 10.7.8a
in the vicinity to help illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
H7 Residential Residents
near lower
Chueng Fu
Street
0 Medium Village sewerage works visible during
construction only but will occupy very
small extent of field of vision.SPS
highly visible. Medium extent of field
of vision.
(See Fig 10.7.12a (VP8))
Fair/ Fair Temporary/
Permanent
Largely
reversible/
Irreversible
Intermediate Intermediate
H8 Residential Inmates of
Tong Fuk
Correction
Institution
390 to SPS Not visible No SPS or STW visible (See Fig 10.7.3) Good Not visible n/a Negligible Negligible
R1 Recreational Hikers on
the Lantau
Trail &
Similar
200 to STW Small STW and SPS partially visible.
Relatively very small extent of field of
vision.
(See Fig 10.7.14a (VP10) and Figs
10.7.5a (VP1) and 10.7.10a (VP6) in
the vicinity to help illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
R2 Recreational Visitors,
Beach users
and
Campers at
Cheung Sha
0 Small SPS visible.
Relatively small extent of field of
vision.
(See Fig 10.7.13a (VP9) in the vicinity
to help illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-39 B&V / ERM
ID
No.
Type of
VSR
Loction of
VSR
Approx. Min.
Distance between
VSRs and
SPS/STW site (m)
Scale of
Development (1)
Degree of visibility of any SPS, STW,
and/or sewer & rising mains
installation/
Potential Blockage Of View (for the
worst affected viewer)
Compatibility
of Project
(Construction/
Operation) (2)
Duration of
Impacts
(Construction/
Operation)
Reversibility of
Change
(Construction/
Operation)
Magnitude of Change
(Negligible / Small /
Intermediate / Large)
Construction Operation
R3 Recreational Hikers on
the South
Lantau
Country
Trail
900 to STW Small STW and SPS partially visible.
Relatively very small extent of field of
vision
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
R4 Recreational Beach users
and users of
the Football
pitch at Pui
O
70 to SPS Small STW and SPS partially visible.
Relatively small extent of field of
vision.
(See Fig 10.7.8a (VP4) in the vicinity to
help illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
R5 Recreational YWCA
users
590 to SPS Not visible No SPS or STW will be visible (See
Fig 10.7.3)
Good Not visible n/a Negligible Negligible
T1 Travelling Travellers
on South
Lantau Road
20 Small STW and SPS partially visible.
Medium extent of field of vision.
During construction, the laying of the
trunk sewerage system and rising mains
is principally along the South Lantau
Road and will be visible to this VSR.
At operation the road will have been
reinstated upon completion of the works
and visual change will be less. Viewers
are principally in vehicles and their
views will be partial and transient.
(See Fig 10.7.6a (VP2) and Fig
10.7.11a (VP7) in the vicinity to help
illustrate)
Fair/ Good Temporary/
Permanent
Largely
reversible/
Irreversible
Intermediate Intermediate
T2 Travelling Travellers
on Tung
Chung Road
(old and
new)
200 to SPS Small SPS too far away to be visible or blocke
d by vegetation. i.e. will not be visible
(See Fig 10.7.3a).
Good Temporary/
Permanent
Largely
reversible/
Irreversible
Small Small
(1) Small/ Medium/ Large
(2) Good / Fair / Low
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-40 B&V / ERM
10.7.6 Significance Threshold of Visual Impacts
The significance threshold of the visual impacts is a product of the magnitude of change
caused by the Project and the sensitivity of the VSR. Table 10.2 shows the significance
thresholds of the VSR impacts while Table 10.9 initially shows the significance thresholds of
visual impacts before mitigation. Mitigation measures, for both landscape and visual impacts,
are detailed in the Section 10.6.8 and Table 10.9 goes on to list appropriate mitigation
measures for each VSR and give the resulting residual landscape impacts.
10.7.7 Visual Mitigation Measures
Several design measures are being considered to reduce the visual impacts of this Project, as
described in MM1 – Detailed Design Considerations of Section 10.6.8. All visual mitigation
measures appropriate to further reduce potential visual impacts are summarised in Section
10.6.8 along with landscape mitigation measures.
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-41 B&V / ERM
Table 10.9 – Significance Thresholds of Visual Impacts
Magnitude of Change
BEFORE Mitigation
(Negligible, Small,
Intermediate, Large)
Impact Significance
Threshold BEFORE
Mitigation (Insignificant,
Slight, Moderate,
Substantial)
Recommende
d Mitigation
Measures
Residual Impact Significance Threshold UPON
Mitigation
(Insignificant, Slight, Moderate, Substantial)
Id
No. VSR Type Location of VSR Sensitivity
Construction Operation Construction Operation Construction
& Operation
Construction Operation
Day 1
Operation
Year 10
H1 Residential
Residents of Shui
Hau Medium Small Small Slight Slight
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Slight Insignificant
H2 Residential
Residents of Tong
Fuk High Intermediate Intermediate Moderate Moderate
MM1, MM2,
MM3, MM6,
MM8 Moderate Moderate Slight
H3 Residential
Residents around
Cheung Sha Medium Small Small Moderate(1) Slight(1)
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Moderate Slight Insignificant
H4 Residential
Residents around
San Shek Wan Medium Small Small Slight(2) Slight(2)
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Insignificant Insignificant
H5 Residential
Residents around
Pui O High Small Small Moderate Moderate
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Moderate Slight Insignificant
H6 Residential
Residents around
Ham Tin High Small Small Moderate Moderate
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Moderate Slight Insignificant
H7 Residential
Residents around
Cheung Fu Street High Intermediate Intermediate Moderate Moderate
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Moderate Moderate Slight
H8 Residential
Inmates of Tong
Fuk Correction
Institution Low Negligible Negligible Insignificant Insignificant n/a Insignificant Insignificant Insignificant
R1 Recreational
Hikers on the
Lantau Trail &
similar Low Small Small Slight Slight
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Slight Slight
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-42 B&V / ERM
Magnitude of Change
BEFORE Mitigation
(Negligible, Small,
Intermediate, Large)
Impact Significance
Threshold BEFORE
Mitigation (Insignificant,
Slight, Moderate,
Substantial)
Recommende
d Mitigation
Measures
Residual Impact Significance Threshold UPON
Mitigation
(Insignificant, Slight, Moderate, Substantial)
Id
No. VSR Type Location of VSR Sensitivity
Construction Operation Construction Operation Construction
& Operation
Construction Operation
Day 1
Operation
Year 10
R2 Recreational
Visitors, Beach
users and Campers
at Cheung Sha Medium Small Small Slight Slight
MM1, MM2,
MM3, MM6,
MM8 Slight Slight Insignificant
R3 Recreational
Hikers on the South
Lantau Country
Trail & similar Low Small Small Slight Slight
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Insignificant Insignificant
R4 Recreational
Beach users and
users of the Football
pitch at Pui O Low Small Small Slight Slight
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Slight Slight
R5 Recreational YWCA users Low Negligible Negligible Insignificant Insignificant n/a Insignificant Insignificant Insignificant
T1 Travelling
Travellers on South
Lantau Road Low Intermediate Intermediate Moderate(3) Moderate(3)
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Moderate Slight Slight
T2 Travelling
Travellers on Tung
Chung Road (old
and new) Low Small Small Slight Slight
MM1, MM2,
MM3, MM4,
MM5, MM6,
MM8 Slight Insignificant Insignificant
Note:
(1) This VSR only has the potential to see the proposed Cheung Sha Trunk SPS and most views are blocked by existing vegetation and other buildings and those who may have views will only have partial views. Residents will be able
to see the construction of the village sewerage system and hence the significance of impact is higher during construction, but no houses are very close to the proposed SPS and the significance of impact is considered to drop at operation
when the pipe works installations are no longer visible.
(2) This VSR only has possible views to the proposed San Shek Wan Trunk SPS but most views are either blocked by vegetation or existing buildings. Roadside planting along south of South Lantau Road which consists of tall trees on
the sloping is proposed and therefore the proposed site/ alternative site of the San Shek Wan SPS at the elevation would only be partially visible to the few houses with views. Residents will be able to see the construction of the village
sewerage system but the proposed SPS will be on the opposite side of the road to all houses and only one house (Ming Garden) close to the road may get a better view of the SPS. Hence the significance of impact is higher during
construction due to laying the pipe works, but the significance of impact is considered to drop at operation when the pipe works installations are no longer visible.
(3) During construction, the laying of the trunk sewerage system and rising mains is principally along the South Lantau Road and will be visible to this VSR. At operation the road will have been reinstated upon completion of the
works and visual change will be less. Viewers are principally in vehicles and their views will be partial and transient
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-43 B&V / ERM
10.7.8 VIA Outcome
During construction, some residential VSRs around Tong Fuk (H2), Cheung Sha (H3), Pui O
(H5), Ham Tin (H6) and near lower Cheung Fu Street (H7) are predicted to experience
moderate visual impacts, as are the Travellers on South Lantau Road (T1) largely due to
laying of the pipe works associated with the Project and these impacts will remain moderate
even upon implementation of some mitigation. By Day 1 of operation however, most of
these impacts will reduce to slight if the suggested mitigation measures are implemented,
with the exception of viewers around Tong Fuk (H2) and Cheung Fu Street (H7) where the
impact will remain moderate at Day 1. By Year 10, all residual visual impacts are considered
to be insignificant with the implementation of suitable mitigation measures, with the
exception of the impact on the residents of Tong Fuk who will still experience slight impact
due to the SPS as well as a house in front of the proposed Cheung Fu Street Trunk SPS on
lower Cheung Fu Street where the impact is considered slight as the current view of a planted
garden area would change to a view of the proposed SPS.
10.8 Cumulative Landscape and Visual Impacts
There are a number of projects in southern Lantau area that interface with the Project, as
summarized below:
PWP No. 257WC – Siu Ho Wan Water Treatment Works Extension – Pui O Raw
Water Pumping Stations and Associated Mainlaying (WSD/Design)
Agreement No. CE 38/2007 (CE) – Planning and Engineering Study of Private Housing
Development at Cheung Sha, Lantau – Feasibility Study (CEDD/HKI&I)
Agreement No. CE 11/2008 (WS) – Replacement and Rehabilitation of Water Mains
Stage 4 (WSD/CM)
CE 29/2008 (EP) – Engineering Investigation and Environmental Studies for Integrated
Waste Management Facilities Phase 1 – Feasibility Study (EPD/IP)
Agreement No. 4600003274 – Cable Route Consultancy Services along Chi Ma Wan
Road (CLP)
RPIS IS009 – Construction of Vehicular Access at Pui O San Wai Tsuen, Lantau Island
(HyD/Works)
RPIS IS005 – Construction of Car Park at Pui O, Lantau Island (HyD/Works)
However, due to unavailable/ non-overlapping project programme or sufficient distance away
from the current Project Site, none of these projects are considered as concurrent projects of
this Project (Section 3.7). Moreover, all these projects will implement necessary mitigation
measures to minimise potential landcape and visual impacts. Therefore associated cumulative
impact is not considered to be significant.
10.9 Conclusion
A Landscape Impact Assessment was undertaken for the construction and operation of the
proposed Project in South Lantau. The magnitudes of change on the LCAs and LRs during
construction and operation are expected vary from negligible to intermediate. Appropriate
Outlying Islands Sewerage Stage 2 –
South Lantau Sewerage Works
10-44 B&V / ERM
landscape measures are proposed to mitigate these landscape impacts and the significance of
residual landscape impacts assessed. Approximately 400 trees will be affected by the Project.
The affected trees are recommended to be retained and protected, felled or transplanted
where appropriate. For those trees felled, compensatory tree planting at a ratio not less than
1:1 according to DEVB TC(W) No. 7/2015 is proposed.
After mitigation at Day 1 of operation, slight landscape impact significance will be
experienced by LR3, LR4 and LR5, while LR1 will experience moderate landscape impact
significance. But with the maturing of soft landscape mitigation vegetation, residual impact
significance of all LRs and LCAs will reduce to insignificant by Year 10 of operation, except
LR1, which will be reduced to slight.
A Visual Impact Assessment was also undertaken for the proposed Project and VSRs were
identified and assessed based on their sensitivity and magnitude of change. Except H2, H7
and T1 during construction and operation stages where the magnitude of change is expected
to be intermediate, the magnitiudes of change on other visual sensitive receviors are expected
to be small or negligible. Visual mitigation measures are proposed as appropriate and
residual visual impacts identified. By Year 10 all residual visual impacts are considered to be
insignificant with the implementation of suitable mitigation measures, with the exception of
residents around Tong Fuk who will still experience slight impact due to the SPS, and the
residents of one house in particular fronting the proposed SPS site on lower Cheung Fu Street
where the impact is considered slight as the current view of a planted garden area would
change to a view of the proposed SPS blocking part of the view of the one or two residents in
this house within the VSR group. Overall, the levels of impact significance during
construction stage are expected to vary from insignificant to moderate and during operation
stage are expected to vary from insignificant to slight.
According to Annexes 10 and 18 of the Technical Memorandum on the Environmental
Impact Assessment Process (EIAO-TM) the Landscape and Visual Impacts are considered
acceptable with mitigation.