10. landscape & visual impact assessment 10.1 introduction · pui o sps 20.1m x 10.2m x 6m...

Outlying Islands Sewerage Stage 2 –

South Lantau Sewerage Works

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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


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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http://www.pland.gov.hk/pland_en/p_study/comp_s/udg/udg_es/dig_eng/urban_cover.htm



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Proposed Above Ground

Development

Zoning Types Affected

(Total Area within OZP)

Zoning Area affected (ha)

Proposed Cheung Sha Trunk

SPS


Proposed San Shek Wan

Trunk SPS



Trunk SPS – Alternative

Option


Proposed Pui O Trunk SPS Coastal Protection Area (CPA) (162.46 ha) 0.18


STW


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

https://www.afcd.gov.hk/tc_chI/publications/publications_con/files/hkbonewsletter8.pdf



10-11 B&V / ERM

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).



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.

../Figures/10.6.5a-g.pdf



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


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


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.




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



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.







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












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









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.






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/


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/


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



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.





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



10-22 B&V / ERM

ID

No.


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)



10-23 B&V / ERM

ID

No.


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.



10-24 B&V / ERM

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.



10-25 B&V / ERM

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



10-26 B&V / ERM

ID

Landscape

Resource/

Landscape

Character

Area

Sensitivity

(Low,

Medium,

High)

Magnitude of Change

BEFORE Mitigation

(Negligible, Small,


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


LR7 Rocky

Shoreline


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



10-27 B&V / ERM

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.


http://www.weather.gov.hk/cis/statistic/hka_redvis_statistic_e.htm



10-28 B&V / ERM

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.



10-29 B&V / ERM

(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


(c) Slight: Adverse/beneficial impact where the Project will cause a barely perceptible


(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



10-30 B&V / ERM

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


../Figures/10.7.3a-b.pdf

../Figures/10.7.5-16.pdf




10-31 B&V / ERM

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.



10-32 B&V / ERM

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.

../Figures/10.7.3b.pdf


../Figures/10.7.3a.pdf



10-33 B&V / ERM

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



10-34 B&V / ERM

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


T2 Travelling Travellers on Tung Chung

Road (old and new)




10-35 B&V / ERM

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.

../Figures/10.7.5-16.pdf











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.







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



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



SPS partially visible.

(See Fig 10.7.7a (VP3))


Permanent

Largely

reversible/

Irreversible

Intermediate Intermediate

H3 Residential Residents

around

Cheung Sha




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


around San

Shek Wan




SPS unlikely to be visible.

(See Fig 10.7.15a (VP11) to help

illustrate)


Permanent

Largely

reversible/

Irreversible

Small Small








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)



installation/



Compatibility

of Project

(Construction/

Operation) (2)

Duration of

Impacts

(Construction/

Operation)

Reversibility of

Change

(Construction/

Operation)

Magnitude of Change





around Pui

O

120 to STW Small Village sewerage works visible during



STW onlypartially visible and SPS

unlikely to be visible.

(See Fig 10.7.16a (VP12) to help

illustrate)


Permanent

Largely

reversible/

Irreversible

Small Small


around Ham

Tin San

Tsuen

20 to SPS Small Village sewerage works visible during



SPS and STW partially visible.


vision.

(See Fig 10.7.9a (VP5) and Fig 10.7.8a

in the vicinity to help illustrate)


Permanent

Largely

reversible/

Irreversible

Small Small


near lower

Chueng Fu

Street

0 Medium Village sewerage works visible during


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


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)


Permanent

Largely

reversible/

Irreversible

Small Small

R2 Recreational Visitors,

Beach users

and

Campers at

Cheung Sha

0 Small SPS visible.


vision.

(See Fig 10.7.13a (VP9) in the vicinity

to help illustrate)


Permanent

Largely

reversible/

Irreversible

Small Small












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)



installation/



Compatibility

of Project

(Construction/

Operation) (2)

Duration of

Impacts

(Construction/

Operation)

Reversibility of

Change

(Construction/

Operation)

Magnitude of Change




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


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.


vision.

(See Fig 10.7.8a (VP4) in the vicinity to

help illustrate)


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)


Permanent

Largely

reversible/

Irreversible


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









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.



10-41 B&V / ERM

Table 10.9 – Significance Thresholds of Visual Impacts

Magnitude of Change

BEFORE Mitigation

(Negligible, Small,


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


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,


H6 Residential

Residents around

Ham Tin High Small Small Moderate Moderate

MM1, MM2,

MM3, MM4,

MM5, MM6,


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



10-42 B&V / ERM

Magnitude of Change

BEFORE Mitigation

(Negligible, Small,


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


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,


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,


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



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



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.

10. landscape & visual impact assessment 10.1 introduction · pui o sps 20.1m x 10.2m x 6m...

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