10. LANDSCAPE AND VISUAL IMPACT 10.1 Figure 10

Drainage Services Department Agreement No. CE 41/2013 (EP)

Port Shelter Sewerage, Stage 3 – Sewerage Works at Po Toi O

Environmental Impact Assessment Studies – Investigation

Environmental Impact Assessment Report

IA13070/EIARpt v2.3 10-1 Cinotech

10. LANDSCAPE AND VISUAL IMPACT

10.1 Introduction

10.1.1 This chapter of the report presents an assessment of the potential landscape and

visual impacts associated with the Port Shelter Sewerage Stage 3 Works, Po Toi O in

accordance with the Environmental Impact Assessment Ordinance (EIAO) and the

requirements of the EIA Study Brief (No. ESB-258/2013). Both construction and

operation impacts are assessed. The Project boundary is illustrated in Figure 10.1.

10.1.2 The assessment includes:

A listing of the relevant environmental legislation and guidelines;

A definition of the scope and contents of the study, including a description of

the assessment methodology;

A review of the relevant planning and development control framework;

A baseline study providing a comprehensive and accurate description of the

baseline landscape and visual resources, landscape character areas, zone of

visual influence and key groups of existing and planned visually sensitive

receivers (VSRs);

Identification of the source of landscape and visual impacts;

Recommendation of appropriate mitigation measures and associated

implementation programmes;

Assessment of the potential landscape and visual impacts, by taking into

account the sensitivity of receivers, prediction of the magnitude of change

experienced by the receivers and resulting potential impact significance, before

and after the mitigation measures; and

Clear evaluations and explanation with supportive arguments of all relevant

factors considered in arriving at the significance thresholds of the landscape

and visual impacts.

10.1.3 Colour photographs showing baseline conditions, and photomontages and illustrative

materials supporting conclusions are provided and the locations of all viewpoints are

clearly mapped. Photomontages at representative locations provide comparison

between existing views; proposals on Day 1 after completion without mitigation; on

Day 1 after mitigation, and in Year 10 after mitigation.

10.2 Landscape and Visual Legislation, Standards and Guidelines

10.2.1 The following environmental legislation, standards and guidelines are applicable to

the evaluation of landscape and visual impacts associated with the construction and

operation of the Project:

(a) Environmental Impact Assessment Ordinance (Cap 499) and the Technical

Memorandum on EIA Process (TM-EIAO), particularly Annexes 3, 10, 11, 18,

20 and 21;






An Ordinance to provide for assessing the impact on the environment of certain

projects and proposals, for protecting the environment and for incidental

matters.

The Technical Memorandum sets out the principles, procedures, guidelines,

requirements and criteria for the technical content of an environmental impact

assessment study brief or Landscape & Visual Impact Assessment Report.

(b) Hong Kong Planning Standards and Guidelines;

The Hong Kong Planning Standards and Guidelines (HKPSG) is a Government

manual of criteria for determining the scale, location and site requirements of

various land uses and facilities.

(c) Landscape Value Mapping of Hong Kong;

Essential landscape baseline information to provide a systematic reference

framework to facilitate landscape assessment and broad environmental

assessment of major projects at territorial level.

(d) EIAO Guidance Note No. 8/2010;

The Environmental Impact Assessment Ordinance, (Cap 499) Guidance Note

advises on the requirements in vetting Landscape and Visual Impact

Assessment of designated projects under the Technical Memorandum on EIA

Process for the Environmental Impact Assessment Ordinance.

(e) Town Planning Ordinance (Cap 131);

To promote the health, safety, convenience and general welfare of the

community by making provision for the systematic preparation and approval of

plans for the lay-out of areas of Hong Kong as well as for the types of building

suitable for erection therein and for the preparation and approval of plans for

areas within which permission is required for development.

(f) Foreshore and Sea-bed (reclamations) Ordinance (Cap 127);

To provide for the publication of proposals in respect of reclamations over and

upon any foreshore and sea-bed; to make provision in respect of objections to

the proposals, the payment of compensation and connected matters; and to

repeal the Public Reclamations and Works Ordinance (Cap 113, 1984 Ed.) and

the Foreshores and Sea Bed Ordinance (Cap 127, 1984 Ed.).

(g) Forests and Countryside Ordinance (Cap 96) and its subsidiary legislation the

Forestry Regulations;

To consolidate and amend the law relating to forests and plants, and to provide

for the protection of the countryside.

(h) Country Parks Ordinance (Cap 208);

To provide for the designation, control and management of country parks and

special areas.

http://en.wikipedia.org/wiki/Forest

http://en.wikipedia.org/wiki/Plant






(i) Marine Parks Ordinance (Cap 476) and associated subsidiary legislation;

To provide for the designation, control and management of Marine Parks and

Marine Reserves.

(j) Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586);

To regulate the import, introduction from the sea, export, re-export, and

possession or control of certain endangered species of animals and plants and

parts and derivatives of those species; and to provide for incidental and

connected matters.

(k) SILTech Publication (1991) – Tree Planting and Maintenance in Hong Kong

(Standing Interdepartmental Landscape Technical Group) [11-23];

(l) GEO publication (1/2009) – Prescriptive Measures for Man-made Slopes and

Retaining Walls;

(m) GEO 1/2011 – Technical Guidelines on Landscape Treatment for Slopes;

This publication presents guidance on good practice for landscape treatments

for man-made slopes and engineering works on natural terrain in Hong Kong.

It is policy to ensure that no tree is felled unnecessarily nor, where control

exists, without the prior consent of Government and that whenever possible,

and appropriate, approval of the felling of any tree is made subject to a

compensatory landscaping/replanting scheme.

(n) DEVB TC (W) No.3/2012 Site Coverage of Greenery for Government

Building Projects;

This circular sets out the standards and requirements on site coverage of

greenery for new government building projects and the methodology of

measurement and calculation for the purpose of the required site coverage of

greenery.

(o) DEVB TC(W) No. 6/2015 – Maintenance of Vegetation and Hard Landscape

Features;

This circular sets out the departmental responsibilities for maintenance of

vegetation and hard landscape features.

(p) ETWB TCW No. 29/2004 – Registration of Old and Valuable Trees, and

Guidelines for their Preservation;

This circular sets out the procedures for registration of old and valuable trees

on unleased Government land within built-up areas and tourist attraction spots

in village areas.

(q) ETWB TCW No. 5/2005 – Protection of Natural Streams/Rivers from Adverse

Impacts Arising from Construction Works;

This circular provides an administrative framework to better protect all natural

streams/rivers from the impacts of construction works. The procedures






promulgated under this Circular aim to clarify and strengthen existing

measures for protection of natural streams/rivers from government projects and

private developments.

(r) DEVB TC(W) No. 7/2015 - Tree Preservation;

This circular sets out the policy on tree preservation, and the procedures for

control of tree felling, transplanting and pruning in Government projects;

(s) WBTC No. 25/93 – Control of Visual Impact of Slopes;

This circular outlines the design principles recommended to be used in

designing manmade slopes for Public Works projects in order to reduce their

adverse visual impact.

(t) WBTC No. 17/2000 – Improvement to the Appearance of slopes in connection

with WBTC 25/93;

This circular outlines the principles and procedures recommended for all

departments involved in new slope formation and in upgrading and

maintenance of existing slopes for reducing the aesthetic and environmental

impact of slope works.

(u) WBTC No. 7/2002 – Tree Planting in Public Works;

This circular affirms the advocated policy on tree planting which adopts a

flexible and balanced approach in the planning and design of tree planting for

public works projects.

(v) Guidelines on Yard Waste Reduction and Treatment issued by DEVB

(GLTM);

These guidelines provide general reference on implementing measures on yard

waste reduction and treatment in various stages from planting design to

maintenance and suggest ways of how yard waste can be reduced, reused and

recycled (3Rs).

(w) Guidelines for Tree Risk Assessment and Management Arrangement issued by

DEVB (GLTM);

These guidelines provide technical and performance guidance on tree risk

assessment, management, monitoring and maintenance.

10.2.2 Review of Relevant Planning and Development Control Framework

A review will be undertaken of the relevant planning and development control

framework for the landscape Study Area (500 m beyond the limit of the

works). The relevant OZP for the project works is the Approved Clearwater

Bay Peninsula South Outline Zoning Plan No. S/SK – CWBS/2, an extract of

which is shown in Figure 10.2 and a description of which is provided in

Section 10.5.3.






10.3 Scope and Content of Study

10.3.1 Project Site Boundary

The Project Site boundary comprises a sewage treatment plant on Po Toi O Chuen

Road, associated sewage mains and a submarine outfall into Clear Water Bay, which

is shown in Figure 10.1.

10.3.2 Major Work Components

(a) Construction of a local sewage treatment plant. The plant will be sited

adjacent to an existing minibus stop on Po Toi O Chuen Road and will consist

of a one storey building approximately 5m above existing ground level and a

hidden basement approximately 10m below ground. The existing site is sloping

and the existing slope will be cut. A retaining wall will be constructed using

the bored pile method. The slope in front and the basement will be excavated.

The sewage treatment plant will then be constructed using reinforced concrete.

A paved run-in/access will be formed on the west side of the plant adjacent to

Po Toi O Tsuen Road. E&M equipment will then be installed prior to testing

and commissioning. Plant used during the construction will include temporary

steel platform for bored pile machine, bored pile machine, crane, dump trucks,

excavators, breakers, concrete trucks and construction materials.

(b) Construction of gravity sewers and rising mains to provide for the un-

sewered areas of Po Toi O. The majority of the proposed pipelines will be

constructed along existing footpaths and a short section will be constructed

along the shoreline. Rising mains and gravity sewers will be constructed by

open trench excavation and a portion of gravity sewers along Po Toi O Chuen

Road will be constructed by trenchless method. Works will be conducted with

hand tools, mini excavators, dump trucks and portable pumps, and materials

imported to Project Site will include the gravity sewers and rising mains pipes

and associated fill, concrete and rebar.

(c) Construction of submarine outfall: The pipeline is intended to ensure that

treated effluent is discharged away from the Po Toi O Fish Culture Zone

(FCZ). It will be constructed by horizontal directional drilling to minimise

dredging requirements. This will require the excavation of a 5m deep

temporary entry pit supported by sheetpiles in the rocky foreshore just to the

north of Po Toi O. During drilling, the pit will be surrounded by various plant

including a power unit, a drill rig, a crane, a mud pump and drill pipes and

casings. Once the drilling has reached the proposed outfall location in the bay,

a receiver pit will be constructed within a sheetpile cofferdam (10m x 50m)

which shall be pumped dry and any marine deposits within dredged. The

height of the cofferdam is anticipated to be 2.7 mPD which will give an

exposed visible portion above sea level of approximately 1.5m. The pipeline

will be attached to the drill bit which will be withdrawn back to the land pit

and connected to the rising mains linked to the sewage treatment plant.

Following pipe connection, the receiving pit will be backfilled to the original

seabed level and the entry pit will be backfilled to the original foreshore levels






and the original condition reinstated. All sheet piles will be removed. All plant

will be imported and exported by sea thereby avoiding any need for temporary

access roads. A barge (18m x 40m) will be stationed in the bay for 7 months

during the construction of the outfall. The barge will have a crane and is

anticipated to have an overall height (including machinery) of 5m above sea

level. A non-permanent smaller barge (12m x 25m) will visit the dredging site

periodically and transport the dredged material off site. The arrangement of

the dredging works site is illustrated indicatively on Figure 10.19a.

(d) The exact layouts, designs and construction methods for individual

components are subject to review during the detailed design stage of the

Project.

(e) There will be temporary landscape and visual impacts during construction of

the submarine outfall. Some elements of the disturbance to the foreshore such

as the felling of existing trees will be noticeable initially during the operation

stage but will be mitigated in the long term by compensatory planting. The

impacts produced from these works including the temporary and permanent

landscape and visual impacts resulting from the construction and operation of

the gravity sewers, rising mains and sewage treatment plant are addressed by

this LVIA.

10.3.3 Limits of Study Area

The limit of the landscape impact study is 500 m beyond the boundary of the works

(as stated in the EIA Study Brief), which is shown in Figure 10.1). The limit of the

visual impact study is the Visual Envelope or the Zone of Visual Influence (ZVI) of

the works during the construction and operation phases (as stated in the EIA study

brief, which is illustrated in Figures 10.9 and 10.10).

10.4 Landscape and Visual Impact Assessment Methodology

10.4.1 General Approach

Landscape and visual impacts shall be assessed separately for the construction and

operation phases. The assessment of landscape impacts shall involve the following

procedures.

10.4.2 Landscape Impact Methodology

(a) Identification of the baseline Landscape Resources (LRs) and Landscape

Character Areas (LCAs) found within the Study Area. This is achieved by

site visits and desk-top studies of topographical maps, information databases

and photographs. Landscape Resources within the Study Area described in

Section 10.3.3 are identified on plan and described in the text. Blank areas do

not constitute Landscape Resources and typically include hard built elements

such as buildings, roads and paved areas. For the mapping of Landscape






Character Areas, reference is first made to the ‘Landscape Value Mapping of

Hong Kong’ study and then updated with reference to current site conditions.

The Figures summarise and formulise the boundaries between distinct

Landscape Resources and Character Areas and do not reflect every variable on

the ground.

(b) Assessment of the degree of sensitivity to change of the LRs and LCAs. This is influenced by a number of factors including whether the

resource/character is common or rare, whether it is considered to be of local,

regional, national or global importance, whether there are any statutory or

regulatory limitations / requirements relating to the resource, the quality of the

resource / character, the maturity of the resource, and the ability of the

resource/character to accommodate change. The sensitivity of each landscape

feature and character area is classified as follows:

High: Important landscape or landscape resource of particularly distinctive

character or high importance, sensitive to relatively small changes

Medium: Landscape or landscape resource of moderately valued landscape

characteristics reasonably tolerant to change

Low: Landscape or landscape resource, the nature of which is largely

tolerant to change

(c) Identification of potential sources of landscape change. These are the

various elements of the construction works and operational procedures that

would generate landscape change.

(d) Identification of the magnitude of landscape change. The magnitude of the

change depends on a number of factors including the physical extent of the

change, the landscape and visual context of the change – i.e. a set

circumstance/facts surrounding the change, the compatibility of the Project

with the surrounding landscape; and the time-scale of the change - i.e. whether

it is temporary (short, medium or long term), permanent but potentially

reversible, or permanent and irreversible. Landscape changes have been

quantified wherever possible. The magnitude of landscape change is classified

as follows:

Large: The landscape or landscape resource would suffer a major

change

Intermediate: The landscape or landscape resource would suffer a moderate

change

Small: The landscape or landscape resource would suffer slight or

barely perceptible changes

Negligible: The landscape or landscape resource would suffer no discernible

change

None: The landscape or landscape resource would suffer absolutely no

impact






(e) Identification of potential landscape mitigation measures. These may take

the form of adopting alternative designs or revisions to the basic engineering

and architectural design to prevent and/or minimise adverse impacts; remedial

measures such as colour and textural treatment of building features; and

compensatory measures such as the implementation of landscape design

measures (e.g. tree planting, creation of new open space etc.) to compensate for

unavoidable adverse impacts and to attempt to generate potentially beneficial

long term impacts. A programme for the mitigation measures is provided. The

agencies responsible for the funding, implementation, management and

maintenance of the mitigation measures are identified and their approvals-in-

principle are being sought.

(f) Prediction of the significance of landscape impacts before and after the

implementation of the mitigation measures. By synthesising the magnitude

of the various changes and the sensitivity of the various landscape resources it

is possible to categorise impacts in a logical, well-reasoned and consistent

fashion. Table 10-1 shows the rationale for dividing the degree of significance

into four thresholds, namely insubstantial, 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 the LRs /

LCAs. The significance thresholds are defined as follows:

Substantial: Adverse / beneficial impact where the proposal would cause

significant deterioration or improvement in existing landscape

quality

Moderate: Adverse / beneficial impact where the proposal would cause a

noticeable deterioration or improvement in existing landscape

quality

Slight: Adverse / beneficial impact where the proposal would cause a

barely perceptible deterioration or improvement in existing

landscape quality

Insubstantial: No discernible change in the existing landscape quality

None Absolutely no change in the existing landscape quality






Table 10-1: Relationship between Receptor Sensitivity and Magnitude of

Change in Defining Impact Significance M

ag

nit

ud

e o

f C

ha

ng

e

Large

Intermediate

Small

Negligible

None

Low Medium High

Receptor Sensitivity

(of Landscape Resource, Landscape Character Area

or VSR)

Note:

The colours in the above table categorise the total spectrum of impacts rising from the lowest value at the bottom

left corner to the highest value at the top right corner. It may be seen that for some combination of classification

levels of Magnitude of Change and Receptor Sensitivity, there are 2 possible impact significance thresholds.

When the Magnitude of Change and Receptor Sensitivity are assessed to be towards the higher ends of each

classification level the resultant impact significance would be deemed to be the higher of the two impact

significance thresholds.

(g) Prediction of Acceptability of Impacts. An overall assessment of the

acceptability, or otherwise, of the impacts according to the five levels of

significance set out in Annex 10 of the EIAO-TM is stated in the conclusion in

Section 10.10.3(a). According to Annex 10, the evaluation of landscape and

visual impacts may be classified into five levels of significance based on type

and extent of the effects concluded in the EIA study:

The impact is beneficial if the project will complement the landscape and

visual character of its setting, will follow the relevant planning objectives and

will improve overall and visual quality;

The impact is acceptable if the assessment indicates that there will be no






significant effects on the landscape, no significant visual effects caused by the

appearance of the project, or no interference with key views;

The impact is acceptable with mitigation measures if there will be some

adverse effects, but these can be eliminated, reduced or offset to a large extent

by specific measures;

The impact is unacceptable if the adverse effects are considered too excessive

and are unable to mitigate practically;

The impact is undetermined if significant adverse effects are likely, but the

extent to which they may occur or may be mitigated cannot be determined

from the study. Further detailed study will be required for the specific effects in

question.

10.4.3 Broad Brush Tree Survey Methodology

(a) A broad brush tree/vegetation survey in accordance with the EIA Study Brief

was undertaken to provide baseline information on the existing trees within the

Project Study Area boundary and identify dominant tree species, maturity,

rarity and any plant species of conservation importance.

(b) Detailed tree surveys have also been undertaken in the vicinity of the Sewage

Treatment Plant and the Submarine Outfall temporary works area in order to

assess the anticipated impacts of the works.

10.4.4 Visual Impact Methodology

(a) Landscape and visual impacts are assessed separately for the construction and

operation phases. The assessment of visual impacts has involved the following

procedures.

(b) Identification of the Visual Envelope and Zones of Visual Influence (ZVI)

during the construction and operation phases. The visual envelope is the

area from which any part of the proposed Project can be seen and may contain

areas, which are fully visible, partly visible and non-visible from the Project.

The ZVI is the portion of the visual envelope that is within 10 km from the

proposed Project. Identification of the visual envelope and ZVI is achieved by

site visits and desk-top studies of topographic maps and photographs to

determine the visibility of the Project from various locations. Given the effects

of distance and the panoramic qualities of many views, VSRs beyond 10 km

from the Project will scarcely notice it (and will find it very difficult to

distinguish) in their wider views. At these distances, the proposed Project will

not form a feature of any significance in the VSRs frame of view and

consequently will not influence the visual experience of the VSR. Hence 10

km is considered the limit of the Zone of Visual Influence.

(c) Identification of the existing Visual Resources within the ZVI including key

visual elements such as land and sea, visual corridors and enclosure provided

by landform.






(d) Identification of the Visually Sensitive Receivers (VSRs) within the ZVI at

construction and operation phases. These are the people who would reside

within, work within, play within, or travel through, the ZVI. VSRs at both

existing and committed developments will be considered in this assessment.

(e) Assessment of the degree of sensitivity to change of the VSRs. Factors

considered include:

The type of VSRs, classified according to whether the person is at home, at

work, at play, or travelling. Those who view the impact from their homes are

considered to be highly sensitive as the attractiveness or otherwise of the

outlook from their home will have a substantial effect on their perception of the

quality and acceptability of their home environment and their general quality of

life. Those who view the impact from their workplace are considered to be only

moderately sensitive as the attractiveness or otherwise of the outlook will have

a less important, although still material, effect on their perception of their

quality of life. The degree to which this applies depends on whether the

workplace is industrial, retail or commercial. Those who view the impact

while taking part in an outdoor leisure activity may display varying sensitivity

depending on the type of leisure activity. Those who view the impact while

travelling on a public thoroughfare will also display varying sensitivity

depending on the speed of travel.

Other factors which are considered (as required by EIAO GN 8/2010) include

the value and quality of existing views and views from planned developments,

the availability and amenity of alternative views, the duration or frequency of

view, and the degree of visibility.

(f) The sensitivity of VSRs is classified as follows:

High: The VSR is highly sensitive to any change in their viewing

experience

Medium: The VSR is moderately sensitive to any change in their viewing

experience

Low: The VSR is only slightly sensitive to any change in their viewing

experience

(g) Identification of the relative numbers of VSRs. This is expressed in terms

of whether there are very few, few, many or very many VSRs in any one

category of VSR.

(h) Identification of potential sources of visual impacts. These are the various

elements of the construction works and operational procedures that would

generate visual impacts.






(i) Assessment of the potential magnitude of visual change. Factors considered

include:

Duration and Frequency

of the impact:

Temporary / Permanent: This refers to the long term

presence of the visual change – whether it is

experienced by the VSR for the whole duration of the

construction phase or operation phase, or only part

thereof.

Intermittent / Continuous: This refers to short term

frequency of the visual change - is it always visible

(continuous) or only at certain times (intermittent).

For example, travelling VSRs may only see the source

intermittently as they travel along their journey,

whereas residential VSRs may have continuous views

from their living room.

Reversibility of the

impact:

Reversible / Irreversible

Compatibility of the

project with the Visual

Backdrop:

High / Medium / Low

Distance of the source of

impact from the viewer:

Shortest distance measured in metres (m) between the

VSR and the source.

Degree of visibility of

Source(s) of Visual

Impact:

Full: virtually full uninterrupted view of the source of

impact

Partial: partial view of the source of impact which is

slightly hidden by intervening elements such as

buildings, vegetation etc.

Obscured: partial view of the source of impact which

is largely hidden by intervening elements such as

buildings, vegetation etc.

Scale of the development Small / Medium / Large

Potential Blockage of

Existing Views

Full / Partial / Slight / Negligible: The degree to

which the source of the impact blocks existing open

views currently experienced by the VSR.






(j) The magnitude of visual change is classified as follows:

Large: The VSRs would suffer a major change in their viewing

experience;

Intermediate: The VSRs would suffer a moderate change in their viewing

experience;

Small: The VSRs would suffer a small change in their viewing

experience;

Negligible: The VSRs would suffer no discernible change in their viewing

experience;

None The VSRs would suffer absolutely no change in their viewing

experience.

(k) Identification of potential visual mitigation measures. These may take the

form of adopting alternative designs or revisions to the basic engineering and

architectural design to prevent and/or minimise adverse impacts; remedial

measures such as colour and finishing treatment of building features; and

compensatory measures such as the implementation of landscape design

measures (e.g. tree planting, creation of new open space etc.) to compensate for

unavoidable adverse impacts and to attempt to generate potentially beneficial

long term impacts. A programme for the mitigation measures shall be

provided. The agencies responsible for the funding, implementation,

management and maintenance of the mitigation measures shall be identified

and their approval-in-principle shall be sought.

(l) Prediction of the significance of visual impacts before and after the

implementation of the mitigation measures. By synthesising the magnitude

of the various visual changes and the sensitivity of the VSR, and the number of

individuals in the VSR that are affected, it is possible to categorise the degree

of significance of the impacts in a logical, well-reasoned and consistent

fashion.

Table 10-1 shows the rationale for dividing the degree of significance into four

thresholds, namely, insubstantial, 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.

Consideration is also given to the relative numbers of individuals in the VSRs

in predicting the final impact significance - exceptionally low or high numbers

of individuals in a VSR may change the result that might otherwise be

concluded from. The significance of the visual impacts is categorised as

follows:






Substantial: Adverse / beneficial impact where the proposal would cause

significant deterioration or improvement in existing visual

quality perceived by the general population;

Moderate: Adverse / beneficial impact where the proposal would cause

a noticeable deterioration or improvement in existing visual

quality perceived by the general population;

Slight: Adverse / beneficial impact where the proposal would cause

a barely perceptible deterioration or improvement in existing

visual quality perceived by the general population;

Insubstantial: No discernible change in the existing visual quality

perceived by the general population;

None Absolutely no change in the existing visual quality perceived

by the general population.

(m) Prediction of Acceptability of Residual Impacts. An overall assessment of

the acceptability or otherwise of the residual impacts 10 to 15 years after

implementation of visual mitigation measures, according to the five criteria set

out in Annex 10 of the EIAO TM is provided.

10.4.5 Assumptions and Limitations

(a) In accordance with EIAO Guidance Note 8/2010 (paragraph 3.7(a)) approved

projects should form part of the baseline conditions. Therefore, the landscape

and visual outcomes (including proposed landscape and visual mitigation

measures) of approved projects currently under construction, should be

included as part of the baseline conditions. However, no major approved

projects in the vicinity have been identified to be carried out prior to or

concurrently with the works within the Project Site.

(b) In addition, the following assumptions are made in the assessment:

Funding, implementation, management and maintenance of the landscape and

visual mitigation proposals must be satisfactorily resolved according to the

principles in DEVB TC(W) No. 6/2015. All mitigation proposals in the EIA

report shall be practical and achievable within the known parameters of

funding, implementation, management and maintenance. The suggested agents

for the funding and implementation (and subsequent management and

maintenance, if applicable) are indicated in the EIA report. Agreement to the

implementation, management and maintenance of the proposed mitigation

measures have been sought and obtained from the appropriate authorities.






10.4.6 Photomontages

(a) Representative views from various locations have been selected to illustrate the

effectiveness of the proposed impact mitigation proposals and residual impacts

of the Project in both the short and long term. Photomontages illustrating the

proposed works and the recommended mitigation measures are listed in

Section 10.7.4. The locations of the selected viewpoints are indicated on

Figures 10.9 and 10.10 with the viewpoints and photomontages illustrated on

Figures 10.14 to 10.18. The photomontages illustrate the proposed

development under the following scenarios:

Existing Baseline Conditions in November 2014;

Day 1 of completed works without mitigation measures;

Day 1 of the completed works with mitigation measures; and

The completed works with mitigation after 10 years.

10.5 Baseline Conditions

10.5.1 Landscape and Visual Study Area

The landscape impact Study Area is 500m from the works boundary and is defined

on Figure 10.1. For the purposes of this assessment, this has been offset from the

location of the Sewage Treatment Plant, and the furthest extent of the submarine

outfall. This encompasses the enclosed bay of Po Toi O which lies on the southern

end of the Clear Water Bay Peninsula. It includes the coastal village areas of Tai

Wong Kung on the west side of the bay and Po Toi O on the east side of the bay. The

western side of the landscape impact Study Area includes the lower slopes of Tin Ha

Shan. The eastern side of the Study Area includes the Clear Water Bay Golf Course

which lies on an elevated headland. Tai Au Mun Road runs through the western edge

of the Study Area and Po Toi O Chuen Road runs through the central part of the

Study Area. The visual study area is defined by the visual envelope or Zone of

Visual Influence (ZVI) and is illustrated on Figures 10.9 and 10.10. The visual

envelope is generally the view shed formed by natural/man-made features such as

ridgelines or building blocks and is the area from which any part of the proposed

Project can be seen and it is thus larger than the landscape study area and includes

Clear Water Bay and its surrounding hills to the north. The absolute outer limit of

the visual envelope for study purposes is 10km beyond which the effects of visual

impacts are negligible due to the distance. For this project, the limits of the ZVI fall

well within the maximum limit ZVI limit due to the natural effects of topography.

Two ZVI’s have been identified, one for the construction stage of the project during

which the temporary construction works associated with the construction of the

submarine outfall in Clear Water Bay will be visible and one for the operation stage

when the temporary visual impacts to Clear Water Bay will no longer be visible.






10.5.2 Committed and Approved Projects under Construction

(a) In accordance with EIAO Guidance Note 8/2010 (paragraph 3.7(a)) approved

projects to be completed before commencement of this Project, should form

part of the baseline conditions. There are two planned major projects within

the Study Area, namely:

(i) Construction of a roundabout near the existing minibus stop in Po Toi O;

and

(ii) Maintenance dredging of Poi Toi O Fish Culture Zone.

There is no definite programme for the above project works and in the absence

of information it is therefore assumed that they will not be carried out

concurrently with the Project.

(b) A review of the current land-uses within the Study Area is outlined below in

Section 10.5.3. The existing LRs and LCAs within the Study Area have been

identified and are described in Sections 10.5.4 and 10.5.5. The sensitivities of

the LRs and LCAs have been summarised in Table 10-2 and Table 10-3.

10.5.3 Review of Current Land-Uses within the Study Area

(a) A review has been undertaken of the current land-use and marine designations

within the landscape Study Area. The relevant OZP for the project works is the

Approved Clear Water Bay Peninsula South Outline Zoning Plan No.S/SK –

CWBS/2 (approved 30 May 2006), an extract of which is shown on Figure

10.2.

(b) The objective of the plan is to specify the broad land use zonings and major

transport network so that any development will be under statutory planning

control.

(c) The following describes the land use zonings on land falling within the

boundaries of the study area which are always permitted and which may be

permitted by the Town Planning Board, with or without conditions on

application.

Coastal Protection Area (“CPA”): This zoning 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 may also cover areas which serve as natural protection areas

sheltering nearby developments against the effects of coastal erosion. There is

a general presumption against development in this zone. In general, only

developments that are needed to support the conservation of the existing

natural landscape or scenic quality of the area or are infrastructure projects

with overriding public interest may be permitted.

Village Type Development (“V”): the planning intention of this zone is to

reflect existing recognized and other villages, and to provide land considered

suitable for village expansion and reprovisioning of village houses affected by






Government projects. Land within this zone is primarily intended for

development of Small Houses by indigenous villagers. It is also intended to

concentrate village type development within this zone for a more orderly

development pattern, efficient use of land and provision of infrastructures and

services. Selected commercial and community uses serving the needs of the

villagers and in support of the village development are always permitted on the

ground floor of a New Territories Exempted House. Other commercial,

community and recreational uses may be permitted on application to the Town

Planning Board.

Open Space (“O”): this zone is intended primarily for the provision of

outdoor open-air public space for active and/or passive recreational uses

serving the needs of local residents as well as the general public.

Green Belt (“GB”): the planning intention of this zone is primarily for

defining the limits of urban and sub-urban development areas by natural

features and to contain urban sprawl as well as to provide passive recreational

outlets. There is a general presumption against development within this zone.

Conservation Area (“CA”): this zoning is intended to protect and retain the

existing natural landscape, ecological or topographical features of the area for

conservation, educational and research purposes and to separate sensitive

natural environment such as Country Park from the adverse effects of

development. There is a general presumption against development in this zone.

In general, only developments that are needed to support the conservation of

the existing natural landscape or scenic quality of the area or are essential

infrastructure projects with overriding public interest may be permitted.

Other Specified Uses (“OU”): this zone is intended primarily for the sport

and recreation club and marina development.

Designated Country Park

Clear Water Bay Country Park lies to the west of the OZP boundary which is

demarcated by Tai Au Mun Road. The small portion lying with the study boundary

consists of natural upland wooded slopes. The proposed Project does not physically

impact the Country Park.

Fish Culture Zone

A gazetted Fish Culture Zone (FCZ) is located in the waters around Po Toi O in

which any development should not affect the water quality. The extent of the FCZ is

indicated on Figure 10.1.






Conclusion

The proposed sewage treatment plant would be constructed on land currently zoned

“CA”. A planning application is required to be submitted to Town Planning Board

for approval separately.

There is no conflict with existing land zoned “O”, “OU”, “GB” and “CPA” as the

predicted extent of area of works does not encroach into these land zonings.

10.5.4 Landscape Resources (LRs)

(a) The baseline LRs that fall within the landscape impact Study Area during the

construction phase and operation phase, together with their sensitivity to

change, are described below. The locations of the LRs are mapped on Figures

10.3a, 10.3b and 10.4. Photo-views illustrating the LRs within the Study Area

are illustrated on Figure 10.6.1 and 10.6.2. For ease of reference and co-

ordination between text, tables and drawings, each LR is given an identity

number.

LR1 –Coastal Waters

(b) This landscape resource consists of the sea area within the enclosed tidal bay of

Po Toi O and beyond the mouth of the bay within Clear Water Bay. It also

includes the intertidal zones of Rocky Shore, Sandy Shore and Mudflat

identified by the Marine Ecological Impact Assessment (MEIA). The MEIA

assessed these habitats as having Low ecological value. The approximate area

is 73.6 ha. Whilst recognising the contribution of this landscape resource to

the unique character of the area, it is abundant in the locality and given its size

and its relatively high tolerance to change, the sensitivity is assessed as

Medium.

LR2 – Streams

(c) There are a number of seasonal natural and semi-natural streams on the steep

slopes surrounding Po Toi O that drain into the bay. Their total length is

approximately 530 m. No species of conservation importance were identified

in the ecological survey and the ecological value of the watercourse habitat is

rated as ‘Very Low’ by the Terrestrial Ecological Impact Assessment (TEIA).

Streams are relatively common in this locality but within Hong Kong as a

whole the occurrence and quality is under great pressure from development.

Overall as a landscape resource, whilst the natural streams have a low

ecological value, given that natural streams are a disappearing resource in

Hong Kong and that they have a medium tolerance to change, their sensitivity

as a landscape resource is assessed as Medium.






LR3 – Natural Rocky Coastline

(d) Natural rocky coastline above high tide level extends within Po Toi O and

around the headlands to the north except for the village developments at Tai

Wong Kung and Po Toi O for a length of approximately 2,300 m. It includes

some scattered, natural, self-seeded trees including Celtis sinensis, Ficus

microcarpa, Macaranga var. tomentosa, Pandanus tectorius, Sterculia

lanceolata and the common seashore shrub Scaevola taccada (refer to the Tree

Survey of the area of the Submarine Outfall in Appendix 10.2). No species of

conservation importance were identified. The TEIA rates the ecological value

of this habitat as ‘Very Low’. However all natural coastline within the study

area is designated as “Coastal Protection Area”. Whilst recognising the scenic

value of this natural landscape resource and the contribution it makes to the Po

Toi O Landscape setting, due to its relative abundance in the locality and its

medium tolerance to change, the sensitivity is assessed as Medium.

LR4 - Natural Coastal Upland Vegetation

(e) The coastal slopes (approximate area 40.3ha) are covered with dense mature

natural woodland and shrubland vegetation. This ranges in height from low

shrubs of 1 to 2 meters height to trees up to 8 meters height in places and is

dominated by native species with some exotic species (further details of

species can be found in the TEIA). Dominant tree species identified on the

slopes below Tai Au Mun Road and Po Toi O Chuen Road include Cerbera

manghas, Macaranga tanarius var. tomentosa, Hibiscus tiliaceus and

Aegiceras corniculatum along the water’s edge. Dominant tree species

adjacent to the developed area include Sterculia lanceolata, Psychotria

asiatica, Microcos nervosa and Ficus hispida. The shrubland areas are

concentrated along the shores and higher altitudes. Above Po Toi Chuen Road

the dominant shrub species identified include Acacia confusa, Gnetum

luofuense, Litsea rotundifolia var. oblingifolia, Miscanthus floridulus and

Schefflera heptaphylla. Around Tai Wang Tung the dominant shrub species

include Mallotus paniculatus and Rhodomyrtus tomentosa. Additional species

noted in LR4 include Ficus variegata, Sapium sebiferum, Sterculia nobilis,

Rhus sacandanea, Phyllanthis emblica and Mallotus apelta. Four tree and

shrub species identified within this LR4 are recognised as having conservation

importance, namely Aquilaria sinensis, Gnetum luofuense, Pavetta

hongkongensis and Diospyros vaccinioides. However, apart from Gnetum

luofuense, these are relatively scarce and do not form dominant species. Five

species of birds of conservation importance have been identified within this

landscape resource. The TEIA rates the overall ecological value of these

habitats as Low to Moderate. This type of vegetated upland covers the

majority of the Clear Water Bay Peninsula but is under increasing pressure

from development on the eastern side. Overall, in terms of a landscape

resource, given its high scenic value and contribution to the distinctive

landscape setting and its contribution as a wildlife habitat and medium

tolerance to change, the sensitivity is assessed as High.






LR5 – Domestic Amenity Tree and Shrub Planting

(f) Mature amenity tree and shrub planting occurs around the village residential

and open space developments. It comprises common amenity species including

ornamental palms including Cocos nucifera, Dypsis lutescens, Phoenix

roebelenii, Roystonea regia, ornamental trees such as Plumeria rubra,

Juniperus chinensis, Araucaria heterophylla, shrubs including Bougainvillea

spp., Malvaviscus arboreus var. penduliflorus, Playcladus orientalis,

Schefflera arboricola and climbers including Ficus pummila. The only plant

species identified of conservation interest identified is Araucaria heterophylla.

The approximate area is 0.2 ha. Given that the vegetation generally comprises

common exotic amenity species found throughout Hong Kong that can be

easily replaced, the sensitivity is assessed as Low.

LR6 – Amenity Grass Areas

(g) There are two amenity grass areas forming part of open spaces within the

village area of Po Toi O and an extensive area of amenity grass forming the

Clear Water Bay Golf Course. The approximate area is 34.6 ha. The TEIA

rates this habitat as having ‘Very Low’ ecological value and no species of

conservation importance were identified. Given that the grass areas are

relatively common, have no conservation status and are easy to reinstate, their

sensitivity is assessed as Low.

LR7 – Artificial Ponds

(h) There are two artificial ponds within the Clear Water Bay Golf Course. The

approximate area is 1.1 ha. The ecological value of these ponds has not been

evaluated by the TEIA. As they are not natural features and have been created

artificially as part of the golf course and appear to be designed for amenity

purposes only (and possibly irrigation storage) and are easy to reinstate, their

sensitivity to change is assessed as Low.

(i) The sensitivities for the LRs identified above are summarised in Table 10-2

below.

Table 10-2: Landscape Resources Ref.

ID. Description

Sensitivity to Change

(Low, Medium, High)

LR1 Coastal waters

Baseline: approx. 73.6 ha Medium

LR2 Streams

Baseline: approx. 530 m Medium

LR3 Natural Rocky Coastline

Baseline: approx. 2,300 m Medium

LR4 Natural Coastal Upland Vegetation

Baseline: approx. 40.3 ha High






Ref.

ID. Description

Sensitivity to Change

(Low, Medium, High)

LR5 Domestic Amenity Tree & Shrub Planting

Baseline: approx. 0.2 ha Low

LR6 Amenity Grass Areas


LR7 Artificial Pond


10.5.5 Landscape Character Areas (LCAs)

(a) Several LCAs have been identified within the Study Area with reference to the

‘Landscape Value Map of Hong Kong’ study and refined with reference to

existing conditions. These areas, and their sensitivity to change, are described

below. The locations of the LCAs are indicated on Figure 10.5a and 10.5b.

Photographic views illustrating the LCAs within the Study Area are illustrated

on Figure 10.7. For ease of reference and co-ordination between text, tables

and drawings each LCA is given an identity number. The below listed LCA’s

represent the baseline condition after completion of the approved committed

projects.

LCA1 – Coastal Upland and Hillside Landscape

(b) This area is characterised by steep slopes of mature woodland and shrubland

and natural rocky cliffs and foreshores. Its approximate area is 61.4 ha. Whilst

the character is relatively common in Hong Kong outside the built-up urban

areas, the scenic quality of this particular area is recognised in the OZP

Explanatory Statement as being worthy of conservation and meriting special

protection. This area provides a stark contrast to the developed eastern side of

the Clear Water Bay peninsular. Given these qualities and overall low

tolerance of change, the sensitivity is assessed as High.

LCA2- Bay Landscape

(c) This LCA comprises part of the open water of Clear Water Bay which enjoys a

relatively sheltered location within the surrounding uplands. Its approximate

area is 70.3 ha. Whilst this type of landscape character is relatively common on

the western side of Hong Kong, this bay is highly frequented by marine craft

for leisure purposes and is prized for its high scenic value and its sensitivity is

therefore assessed as High.

LCA3 – Intertidal Bay Landscape

(d) This LCA comprises the unique setting of the waterbody within Po Toi O.

Such degree of enclosure of natural sea areas is rare in Hong Kong. Its

approximate area is 15.0 ha. The bay is relatively shallow and the character

changes with the rise and fall of the tide. The bay supports fish culture

activities and the combination of enclosed water, local marine craft, fish






culture enclosures and changing waterline creates a scene of high visual value

and interest. Its ability to accommodate change is relatively low. Given these

attributes, the sensitivity of the LCA to change is assessed as High.

LCA4 - Coastal Village Landscape

(e) This LCA comprises the coastal village developments of Tai Wong Kung on

the western side of the bay and Po Toi O on the eastern side of the bay. Its

approximate area is 5.8 ha. The villages consist of a mixture of residential and

commercial developments including sea food restaurants. The scale of the

buildings is generally small and restricted to 3 storeys or less. Whilst the

overall scene has a degree of attractiveness, the visual and historic quality of

the individual structures is generally low (except for certain historic buildings

such as temples). This type of coastal village development is also relatively

common throughout Hong Kong’s coastline. As the overall value of this LCA

is due primarily to its setting and the scale and assemblage of structures, it has

a reasonable tolerance of change. The sensitivity is therefore assessed as

Medium.

LCA5 - Golf Course Landscape

(f) This LCA comprises the Clear Water Bay Golf Club which occupies the high

ground to the east of Po Toi O above the tree clad coastal margin. Its

approximate area is 33.9 ha. The character is one of open, rolling, contoured,

amenity grassland with ornamental tree groups. The LCA benefits from its

proximity and views over the adjacent natural landscape areas and is otherwise

typical of heavily managed golf course landscapes. Golf course landscapes are

reasonably common in Hong Kong and as this Landscape Character Area is

unremarkable, has no conservation status and is tolerant to change and easily

replicated, the sensitivity is assessed as Low.

The sensitivities for the LCAs identified above are summarised in Table 10-3 below.

Table 10-3: Landscape Character Areas

Ref.

ID. Description

Sensitivity to Change (Low, Medium, High)

LCA1 Coastal Upland and Hillside Landscape

Baseline: 61.4 ha High

LCA2 Bay Landscape


LCA3 Intertidal Bay Landscape


LCA4 Coastal Village Landscape

Baseline: 5.8 ha Medium

LCA5 Golf Course Landscape

Baseline: 33.9 ha Low






10.5.6 Tree Survey

(a) A broad tree/vegetation survey was undertaken within the Project Site

boundary described in Section 10.3.1. The findings with dominant species and

species of conservation importance are provided in the descriptions for each

relevant Landscape Resource above. Approximate areas of the landscape

resources have been provided.

(b) Detailed individual tree surveys were undertaken for the area of the proposed

sewage treatment plant and the shoreline area of the submarine outfall where

temporary construction works will take place (the Tree Survey Plans, Tree

Assessment Schedules and Tree Photographs are provided in Appendix 10.1

and Appendix 10.2 for the two areas respectively). 13 trees were surveyed at

the sewage treatment plant comprising the following species: Acacia confusa,

Ficus microcarpa, Ficus variegata (2 no.), Macaranga tanarius var. tomentosa

(2 no), Mallotus apelta, Sapium sebiferum, Schefflera heptaphylla, Rhus

succedanea, Phyllanthus emblica (2 no.) and Sterculia nobilis. At the sewage

outfall shoreline, 23 live trees were surveyed including the following species:

Celtis sinensis (3 no.), Ficus microcarpa, Macaranga tanarius var. tomentosa

(7 no.), Sterculia lanceolata (2 no.) and Pandanus tectorius (10 no.). Two

dead trees were also recorded.

(c) No rare or endangered tree species and no “Old and Valuable Trees” (OVTs)

as defined under ETWB TC(W) 29/2004 or listed in the LCSD OVT Register,

and no potential OVTs or “Important Trees” (ITs) as defined by DEVB TC(W)

7/2015 were identified within the detailed tree survey areas.

10.5.7 Summary of Tree Impacts

(a) Sewage Treatment Plant: Tree impacts will be minimised and limited to the

footprint of the STP building. Tree impacts from the inlet sewer pipe will be

avoided as it will be installed 10m below ground level using a trenchless

method. A total 13 no. trees were surveyed of which 4 no. trees are anticipated

to be affected in order to construct the sewage treatment plant. These trees are

T1, T2, T3 and T13 which are unsuitable for transplanting and will be felled.

Details of the trees are provided in the Tree Assessment Schedule in Appendix

10.1. Tree preservation and compensatory tree planting will be carried out in

accordance with DEVB TC(W) No. 7/2015 Tree Preservation.. This requires a

compensatory planting ratio of a minimum 1:1 by number. 12 no. heavy

standard trees are proposed to be planted in the vicinity of the sewage

treatment plant (refer Compensatory Trees Plan in Figure 10.20).

(b) Submarine Outfall: 25 no. trees were surveyed of which 2 no. were dead. The

trees are self-seeded native species and are of poor to fair health, low to

medium amenity value and have a low suitability for transplanting due to their

rooting condition on the rocky seashore. Details of the trees are provided in the

Tree Assessment Schedule in Appendix 10.2. 1 no. living tree will be retained.

22 no. of the 23 no. living trees will be impacted by the temporary works area

on the shoreline during the construction of the outfall and it is proposed to fell

them and the 2 no. dead trees (total 24 no. trees felled). Tree preservation and






compensatory tree planting will be carried out in accordance with DEVB

TC(W) No. 7/2015. This requires a compensatory planting ratio of a minimum

1:1 by number. A minimum of 24 no. heavy standard trees will be planted on

the shoreline to compensate for the felled trees (refer Figure 10.19b).

10.5.8 Baseline Visual Elements

(a) Key visual elements are illustrated on Figure 10.8.1 and photographs of the

visual corridors are provided on Figure 10.8.2. The visual enclosure of the

study area is defined by the ridgeline of the hills surrounding Clear Water Bay.

Key visual corridors include the open vistas from the bay towards the open sea

to the east and the views up and down the enclosed, elongated bay of Po Toi O.

The key viewpoints within the study area are also illustrated and correspond to

areas of high ground, settlement and recreational sites.

(b) The key visual elements are described below:

(i) The visual context is dominated by the natural topography that consists

of steep vegetated slopes rising from the sea to peaks and ridgelines that

form an arc from the north east to the south east that defines the visual

envelope of the Project site (refer Figure 10.8.2, VC3 for typical

character of the landform). The landform includes ridges, valleys,

headlands and the coastline encloses large seawater bays.

(ii) Two seawater bays provide a dramatic contrast to the landward

topography. Clear Water Bay is the largest of the two and lies to the

north and Po Toi O is smaller and more enclosed and lies to the south

(refer Figure 10.8.2, VC1 to VC4).

(iii) The coastline is predominantly rocky and steep forming a wild and

rugged shore (refer Figure 10.8.2, VC2). Clear Water Bay First and

Second Beaches are sandy stretches that are popular with visitors due to

their scenic quality. The southern portion of Po Toi O is shallow and the

intertidal zone forms distinctive mudflats at low tide.

(iv) Small village type settlements have grown up on the fringes of the coast

in Po Toi O (refer Figure 10.8.2, VC4) and in valley locations such as

Tai Au Mun. These are of small scale and provide an interesting visual

contrast to the natural elements.

(v) Roads serving the area are visually prominent when viewed from

elevated viewpoints as they form a break in the vegetated hillslopes (refer

Figure 10.8.2, VC2). However their alignment generally follows the

natural contours which aid their integration with the general visual

context.

(vi) The eastern portion of the headland enclosing Po Toi O is occupied by

the Clear Water Bay Golf Course. The rolling modified landform with

open expanse of amenity sports turf forms a visual contrast to the natural

vegetation cladding the hills in the rest of the study area (refer Figure

10.7, LCA5).






(c) Key Viewpoints are illustrated on Figure 10.8.1. These represent locations

offering expansive views of the locality and include the following:

(i) View from Tai Leng Tung: hikers on the trails on this mountain have

expansive panoramic views to the south over the Project site (refer

Figure 10.8.4, REC-4).

(ii) View from Clear Water Bay Country Park Visitor Centre: visitors and

workers have expansive panoramic views to the south over the Project

site (refer Figure 10.17, Photomontage Viewpoint 4).

(iii) Tai Au Mun: residents in Tai Au Mun have expansive panoramic views

to the south over the Project site (refer Figure 10.8.3, RES-5).

(iv) High Junk Peak: at 344m, this hill represents the high point of the High

Junk Peak Country Trail and affords hikers expansive panoramic views

to the south east over the Project site (refer Figure 10.8.5, REC-7).

(v) Clear Water Bay First and Second Beaches: these beaches provide open,

panoramic views east across Clear Water Bay (refer Figure 10.8.5,

REC-8 and REC-9, and Figure 10.18, Photomontage Viewpoint 5).

(vi) Tin Ha Shan: at 273m, this hill is the first vantage point of the High Junk

Peak Country Trail and affords hikers expansive views east across the

Project site (refer Figure 10.8.4, REC-1).

(vii) Tai Wong Kung: residents experience panoramic views east and south

across Po Toi O (refer Figure 10.8.3, RES-2).

(viii) Tai Au Mun Road: motorists experience panoramic views east across Po

Toi O (refer Figure 10.15, Photomontage Viewpoint 2).

(ix) Clear Water Bay Golf Course: players on the course have elevated

panoramic views north and west across Po Toi O (refer Figure 10.8.4,

REC-2).

(x) Fairway Vista: residents have panoramic views west across upper Po Toi

O (refer Figure 10.8.3, RES-4).

(d) Overall the study area is one of high visual quality with the vegetated

topography, rocky coastline and sea providing the dominant visual elements.

The coastal village settlements integrate well visually due to their small scale

and organic layout. The primary roads serving the area tend to follow the

contours and whilst they are visible elements, do not detract greatly from the

overall visual quality of the area. Whilst the Clear Water Bay Golf Course

adopts a different landform and vegetation type, it visually complements the

natural landscape with its rolling green forms and tones. There are no

significant visual detractors within the study area.

10.5.9 Zone of Visual Influence (ZVI)

(a) The ZVI’s for the Construction and Operation Phases of the Project have been

mapped based on the exposure of the proposed development to the surrounding

environment and are illustrated on Figures 10.9 and 10.10. The ZVI for the

Construction Phase is larger than for the Operation Phase because the

submarine outfall construction works will only be visible during the

Construction Phase and not during the Operation Phase. In accordance with

EIAO GN 8/2010 the ZVI may contain areas which are fully visible, partly

visible, and non-visible from the Project. Areas of visual shadow may occur






within the ZVI due to intervening topography, dense vegetation and man-made

structures.

(b) The ZVI during the Construction Phase is contained by the surrounding

uplands of Po Toi O from which the construction work of the Sewage

Treatment Plant could potentially be seen. Temporary construction works for

the submarine outfall will be potentially seen from vantage points on the north

side of Clear Water Bay resulting in an extended ZVI to the north.

(c) The ZVI during the Operation Phase is reduced in area to the uplands around

Po Toi O as the only permanent visual impacts will be created by the sewage

treatment plant. The temporary construction impacts previously visible in

Clearwater Bay during the Construction Phase would no longer be visible as

the treated sewage outfall will be underwater.

10.5.10 Visually Sensitive Receivers (VSRs)

(a) Within the ZVI, a number of key VSRs have been identified. These VSRs are

mapped on Figures 10.9 and 10.10 and are listed in Table 10-4.

(b) For ease of reference, each VSR is given an identity number, which is used in

the text tables and drawings.

(c) The sensitivity of each VSR is given in Table 10-4 below.

10.5.11 The residential VSRs RES-1 to RES-5 are few in number due to the small scale

village type development of the settlements. Their sensitivity to visual change is

assessed as ‘High’ due to their existing, static permanent views.

10.5.12 The recreational VSRs REC-1, REC-3, REC-4, REC-5, REC-7, REC-8 and REC-

9 all have ‘High’ sensitivity to change a hikers, visitors to country parks, scenic

beaches and bays do so specifically to enjoy a high quality of visual experience.

REC-2 Players on Clear Water Bay Golf Course and REC-6 Visitors to Seafood

Restaurants in Po Toi O are assessed as having a ‘Medium’ sensitivity to visual

change as the view is secondary to their primary activities of golf and dining

respectively.

10.5.13 The Travelling VSRs T-1a to T-3 have been assessed as having a ‘Medium’

sensitivity to change as although their visual experience is short-lived and their

reason for travel may be varied, their visual experience of this scenic area is

important to the quality of their driving experience.

10.5.14 The occupational VSRs O-1 to O-3 are assessed as having a ‘Low’ sensitivity to

visual change as their primary focus in not on their external environment.






Table 10-4: Key Visually Sensitive Receivers (VSRs)

VSR ID. Key VSR

Value and Quality

of Existing View

(Poor, Fair , Good)

Availability of

Alternative Views

(Yes, No)

Number of Individuals (Very

Few, Many,

Very Many)


Construction Operation Construction Operation

Residential VSRs

RES-1 Residents in Po Toi O Village Good Yes Few Few High High

RES-2 Residents at Tai Wong Kung Good Yes Few Few High High

RES-3 Residents of Cala d’Or Good Yes Few Few High High

RES-4 Residents in Fairway Vista Good Yes Few Few High High

RES-5 Residents at Tai Au Mun Good Yes Few Few High High

Recreational VSRs

REC-1 Hikers on Tin Ha Shan Good Yes Few Few High High

REC-2 Players on the Clear Water Bay Golf Course Good Yes Few Few Medium Medium

REC-3 Visitors to Clear Water Bay Country Park Visitor

Centre Good Yes Many Many High High

REC-4 Hikers on Tai Leng Tung Good Yes Few Few High High

REC-5 Recreational Craft in Clear Water Bay Good Yes Many Many High High

REC6 Visitors to Seafood Restaurants in Po Toi O Good Yes Many Many Medium Medium

REC-7 Hikers on High Junk Peak Country Trail Good Yes Few Few High High

REC-8 Users of Clear Water Bay First Beach Good Yes Many Many High High

REC-9 Users of Clear Water Bay Second Beach Good Yes Many Many High High

Travelling VSRs

T-1a Drivers/Passengers along Tai Au Mun Road Good Yes Many Many Medium Medium

T-1b Drivers/Passengers along Tai Au Mun Road Good Yes Many Many Medium Medium

T-2 Drivers/Passengers along Poi To O Chuen Road Good Yes Many Many Medium Medium

T-3 Drivers/Passengers along Clear Water Bay Road to

Tai Hang Tun Good Yes Many Many Medium Medium






VSR ID. Key VSR

Value and Quality

of Existing View

(Poor, Fair , Good)

Availability of

Alternative Views

(Yes, No)

Number of Individuals (Very

Few, Many,

Very Many)


Construction Operation Construction Operation

Occupational VSRs

O-1 Fishermen in Po Toi O Good Yes Few Few Low Low

O-2 Workers / Staff at Clear Water Bay Country Park

Visitor Centre

Good Yes Few Few Low Low

O-3 Workers in Seafood Restaurants in Po Toi O Good Yes Few Few Low Low

Note: ‘Duration and Frequency of Views’ and ‘Degree of Visibility’ have been taken into account in assessing the magnitude of change in view experience by the VSRs and cannot be double counted in

determining the sensitivity of the VSR.






10.6 Landscape Impact Assessment

10.6.1 Potential Sources of Impacts

(a) The nature and scope of the works has been described in Section 10.3 and

indicated on Figure 10.1.

(b) The Proposed Project would create varying levels of landscape and visual

impacts on the surrounding areas during the Construction Phase. Potential

impacts would result from the following sources:

Site clearance works at the sewage treatment plant involving the removal of

existing trees & vegetation;

Slope and site excavation works at sewage treatment plant;

Excavation of trenches along gravity sewers and rising mains alignment;

Haulage off-site of excavated materials;

Stockpiling of materials for construction of gravity sewers and rising mains

trenches and sewage treatment plant;

Dust and construction debris;

Construction of on-site offices and working areas;

Temporary road works and traffic management;

Construction night lighting;

Presence of temporary construction plant, platforms, structures and

construction machinery;

Drilling rig and associated plant for drilling of submarine pipeline on the

foreshore north of Po Toi O;

Temporary cofferdam (10m x 50m, approximately 1.5m above sea surface) and

receiving pit in location of submarine sewage outfall;

Barge (~18m x 40m x 5m height (including machinery such as crane) for

dredging at location of submarine sewage outfall; and

Temporary 3m high movable noise barriers around the sewage treatment plant,

along gravity sewers and rising mains alignment; semi-noise enclosure around

the drilling plant for the submarine pipeline on the foreshore of Po Toi O

(enclosure shall enclose the stationary plant on 3 sides with the side facing the

sea left open for heat exhaust; the top shall also be covered).

(c) The Proposed Project would create varying levels of landscape and visual

impacts on the surrounding areas during the Operation Phase. Potential

impacts would result from the following sources:

Cleared area of foreshore previously used for temporary drilling plant.

Presence of new sewage treatment building and associated access/parking

areas;






Presence of gravity sewers and rising mains trench covers along existing

village roads; and

Additional operational night lighting.

10.6.2 Landscape Change before Mitigation in Construction Phase

The magnitude of change, before implementation of mitigation measures, on the

landscape resources and landscape character areas that would occur in the

Construction Phase is summarised below and tabulated in Table 10-5. All impacts

are adverse unless otherwise stated.

Landscape Resources

(a) LR1- Coastal Waters: the dredging works for the submarine outfall will

impact a limited area of the coastal waters within a cofferdam and due to the

presence of a barge. Given that the impacts only occupy a very small portion of

this LR (0.12ha comprising 500 sq.m dredging pit and 720 sq.m barge) and

will be temporary, the magnitude of change on coastal waters due to the

dredging for the sewage outfall is assessed as Small.

(b) LR2 - Streams: there will be no impacts on existing streams. There is a

stream located to the north of the proposed STP. No water flowed in this

stream in both wet and dry seasons during the site visits. It will be unaffected

by the installation of Sewage Treatment Pipework as the pipes will be installed

by the trenchless method beneath the stream bed. No alternation of the course

or damage to the stream bed will be resulted by the proposed works. The

magnitude of change is therefore assessed as None.

(c) LR3 – Natural Rocky Coastline: the drilling works for the submarine outfall

will occupy a short length of the natural rocky coastline (estimated 40m long,

total area 750 sq.m) for a limited amount of time. In addition, 24 no. existing

trees will be felled (2 no. dead and 22 no. living trees) to create space for

temporary construction plant. No species of conservation importance will be

impacted. Given the overall size of this Landscape Resource, the magnitude of

change is assessed as Small.

(d) LR4 – Natural Coastal Upland Vegetation: due to the construction of the

sewage treatment plant, 4 no. existing trees will be felled and approximately

0.089ha of slope vegetation will be impacted. Of the 4 no. plant species of

conservation importance identified within this Landscape Resource, only one

individual of Gnetum luofuense on the slope above the Sewage Treatment Plant

will potentially be impacted. Given the minimal impact to existing vegetation

and the size of the area affected compared to the overall area of LR4 (43.1 ha),

the magnitude of change is assessed as Small.

(e) LR5 – Domestic Amenity Tree and Shrub Planting: there will be no impacts

on the domestic planting area (including species identified of conservation

importance) and the magnitude of change is therefore assessed as None.






(f) LR6 – Amenity Grass Areas: there will be no impacts on existing amenity

grass area and the magnitude of change is therefore assessed as None.

(g) LR7 – Artificial Ponds: there will be no impacts on artificial ponds and the

magnitude of change is therefore assessed as None.

Landscape Character Areas

(h) LCA1 - Coastal Upland and Hillside Landscape: impacts on this LCA

include the loss of 4 no. existing trees and 0.089 ha of the associated vegetated

slope area and the construction of the sewage treatment plant. However, as the

area of impact is very minor (approximately 0.089ha) in relation to the total

area of the LCA (61.4 ha), the magnitude of change is assessed as Small.

(i) LCA2 – Bay Landscape: during the Construction Stage, this LCA will

experience some minor dredging operations and the presence of a barge at the

sewage outfall location. However, as the area affected is only 0.12ha and very

minor (approximately 500 sq.m or 0.05ha for dredging pit and 0.072 ha barge)

in relation to the total area of the LCA (70.3 ha), the magnitude of change is

assessed as Small.

(j) LCA3 - Intertidal Bay Landscape: there will be no impacts to this LCA

during the Construction and Operation Stages and the magnitude of change is

therefore assessed as None.

(k) LCA4 - Coastal Village Landscape: during the Construction Stage there will

be minor impacts to this LCA caused by the drilling rig and plant for the

submarine pipeline construction and the excavation and construction of the

gravity sewers and rising mains trenches. However, as the area affected is very

minor (approximately 0.32ha) in relation to the area of the LCA (5.8ha), the

magnitude of change is assessed as Small.

(l) LCA5 – Golf Course Landscape: there will be no impacts to this LCA

during the Construction and Operation Stages and the magnitude of change is


10.6.3 Landscape Change Before Mitigation in Operation Phase

(a) The magnitude of change, before implementation of mitigation measures, on

the landscape resources and landscape character areas that would occur in the

operation phase is described below and tabulated in Table 10-5. All impacts

are adverse unless otherwise stated.

Landscape Resources

(b) LR1 – Coastal Waters: the temporary impacts of the dredging works will not

be experienced during the Operational Phase and the magnitude of change is







(c) LR3 – Natural Rocky Coastline: the temporary impacts of the drilling plant

will not be experienced during the Operational Phase. However, the remaining

loss of 22 existing living trees from the shoreline will result in a magnitude of

change of Small.

(d) LR4 – Natural Coastal Upland Vegetation: the degree of impact will be

slightly smaller than during the Construction Phase due to the absence of plant,

machinery and vehicles. However, the presence of the Sewage Treatment Plant

will result in the permanent loss of approximately 0.089ha of Natural Coastal

Upland Vegetation (including 4 no. existing trees). As this is a very small

portion in relation to the total area of this LR (43.1 ha) within the Study Area

described in Section 10.3.3, the magnitude of change is assessed as Small.

(e) The magnitude of change before mitigation, on the remaining landscape

resources (LR2, LR5, LR6 and LR7) in the operation phase are the same as

described for the construction phase, i.e. None.


(f) LCA1 – Coastal Upland and Hillside Landscape: the sewage treatment plant

will result in the permanent loss of 0.089 ha. of this LCA including 4 no.

existing trees. As this is a very small portion in relation to the total area (61.4

ha) of this LR within the Study Area, the magnitude of change is assessed as

Small.

(g) LCA2 – Bay Landscape: the temporary impacts of the dredging works will

not be experienced during the Operational Phase and the magnitude of change

is therefore assessed as None.

(h) LCA4 - Coastal Village Landscape: there will be minor impacts

(approximately 0.06ha) to this LCA caused by the trench covers of the

pipelines. However, these are within existing paved areas and the impact is

therefore negligible. There will also be the continued absence of the 22 no.

trees felled to create space for the temporary works area on the foreshore and

some disturbance to 0.075 ha of the rocky shoreline. However, the overall

magnitude of change for this LR is assessed as Small.

(i) The magnitude of change before mitigation, on the remaining landscape

resources (LCA3 and LCA5) in the operation phase are the same as described

for the construction phase, i.e. None.






Table 10-5: Magnitude of Landscape Change during the Construction and Operation Phases before Mitigation ID No. Landscape Resources/


Source of Impact Description of Impacts Magnitude of

Change before

Mitigation

LR1

Coastal Waters Construction

- Barge, and construction of cofferdam for dredging pit,

dredging works at location of submarine outfall.

Construction

- Temporary loss of approximately 0.12 ha of

coastal waters (500 sq.m dredging pit & 720

sq.m. barge)

- Baseline area: 73.6 ha.

- Increased marine traffic/presence of dredging

barge

Small

Operation

- None

Operation

- None

None

LR2

Streams Construction

- None

Construction

- None

None

Operation

- None

Operation

- None

None

LR3

Natural Rocky Coastline Construction

- Temporary construction plant, platforms, structures,

construction machinery.

- Drilling rig for drilling of submarine pipe.

Construction

- Presence of temporary drilling rig and plant,

approximate length of 40m (approximate area

750 sq.m); loss of 22 no. existing living trees

- Baseline length: 2,300m, 23 no. existing living

trees.

Small

Operation

- None

Operation

- Disturbed surface of rocky shoreline caused by

temporary plant; absence of 22 no. existing living

trees.

Small

LR4

Natural Coastal Upland

Vegetation

Construction

- Site clearance works at the sewage treatment plant

involving the removal of existing trees & vegetation;

- Slope and site excavation works at sewage treatment

plant; - Excavation of trenches along gravity sewers and rising

mains alignment;

- Dust and construction debris;

- Construction of on-site offices and working areas;

- Construction of temporary plant, platforms, structures,

construction machinery and construction vehicle traffic.

Construction

- Loss of 4 no. existing trees

- Impacts to approximate area of 0.089 ha.

- Baseline area: 40.3 ha., 13 no. existing trees

Small






ID No. Landscape Resources/



Change before

Mitigation

Operation

- New sewage treatment building;

Operation

- Presence of new sewage treatment plant and

associated access/parking areas

- Absence of 4 no. existing trees

- Approximate area: 0.089 ha.


Small

LR5

Domestic Amenity Tree &

Shrub Planting

Construction

- None

Construction

- None

None

Operation

- None

Operation

- None

None

LR6

Amenity Grass Areas Construction

None

Construction

None

None

Operation

None

Operation

- None

None

LR7

Artificial Ponds

Construction

None

Construction

None

None

Operation

None

Operation

- None

None

LCA1

Coastal Upland and Hillside

Landscape

Construction

- Site clearance works at the sewage treatment plant

involving the removal of existing trees & vegetation;

- Slope and site excavation works at sewage treatment

plant;

- Excavation of trenches along gravity sewers and rising

mains alignment;


- Construction of on-site offices and working areas;

- Temporary construction plant, platforms, structures,

construction machinery and construction vehicle traffic.

Construction

- Loss of 4 no. existing trees

- Impacts to approximate area of 0.089 ha.


Small

Operation

- New sewage treatment building;

Operation

- Presence of new sewage treatment plant and

associated access/parking areas


- Approximate area: 0.089 ha.


Small






ID No. Landscape Resources/



Change before

Mitigation

LCA2

Bay Landscape Construction

- Barge, construction of cofferdam for dredging pit,

dredging works at location of submarine sewage outfall.

Construction

- Temporary loss of approximately 0.12 ha of

coastal waters

- Baseline area: 73.6 ha.

- Increased marine traffic/presence of dredging

barges

Small

Operation

- None

Operation

- None

None

LCA3

Intertidal Bay Landscape Construction

- None

Construction

- None

None

Operation

- None

Operation

- None

None

LCA4

Coastal Village Landscape Construction

- Excavation of trenches along gravity sewers and rising

mains alignment;

- Haulage off-site of excavated materials;

- Stockpiling of materials for construction of pipe

trenches and sewage treatment plant;


- Presence of temporary construction plant, platforms,

structures, construction machinery and construction

vehicle traffic at drilling site for submarine outfall;

Construction

- Temporary occupation of approximately 0.32 ha

by construction operations

- Loss of 22 no. existing living trees

- Baseline area: 5.8 ha, 23 no. existing living trees

Small

Operation

- Gravity sewers and rising mains trench covers

Operation

- Presence of gravity sewers and rising mains

trench covers – 0.06 ha

- Presence of disturbed foreshore – 0.075ha


- Baseline area: 5.8 ha., 23 no. existing living trees

Small

LCA5

Golf Course Landscape Construction

- None

Construction

- None

None

Operation

- None

Operation

- None

None

* Assumptions have been made due to lack of detailed design information at this stage






10.6.4 Landscape & Visual Mitigation Measures

Review of Planning Principles and Architectural Design

(a) Given the site context of the Project within a sensitive environment (designated

Conservation Area and Coastal Protection Area), the architectural design of the

permanent visible structures must be designed to minimise physical and visual

impacts and enhance the quality of the Project. The architectural design of the

sewage treatment plant adopts the following principles which shall be adopted

during the detailed design, and will be built as part of the construction works so

that they are in place at the date of commissioning of the Sewage Treatment

Plant.

(b) Minimisation of the building footprint during the planning and design stage to

reduce the area of impact on sensitive landscape resources and landscape

character areas.

(c) Minimisation of the height, bulk and scale of the building. Given that the

building lies within close proximity to “V” Village Type Development where

there is a general restriction of height to 3 storeys, the sewage treatment plants

should seek to reduce its building height to reflect the scale of the existing

village development and minimise visual intrusion. Figure 10.14 shows a

photomontage of the sewage treatment plant at Day 1 and Year 10 with

mitigation measures. The height of the building is limited to one storey only

with much of the facility accommodated underground out of sight. This

greatly reduces the apparent bulk and scale of the building. The facade of the

sewage treatment plant will be covered by climbing plants to integrate the

building with the green backdrop. The visual impact is further reduced by the

perimeter fence which screens much of the low building from view. The visual

impact of the fence itself is mitigated by climber planting which helps integrate

the sewage treatment plant compound into the green backdrop of the hills

behind.

(d) In addition, a number of landscape and visual mitigation measures are

identified below to further mitigate adverse impacts and promote beneficial

impacts. The proposed landscape and visual mitigation measures for potential

impacts generated during the construction and operation phases together with

the associated funding, implementation, management and maintenance

agencies are described below in Table 10-6 and Table 10-7 and illustrated on

Figures 10.19a, 10.19b and 10.20.






Table 10-6: Proposed Construction Phase Landscape and Visual Mitigation

Measures

ID No. Landscape and Visual Mitigation Measure Landscape

measure

Visual

measure

Funding

Agency

Implementation

Agency

CM1 The construction area and contractor’s

temporary works areas should be minimised

to avoid impacts on adjacent landscape. All

slope excavation shall take place from within

the work boundary to minimise impacts on

adjacent slopes.

✓ ✓ DSD Contractor

CM2 Reduction of construction period to practical minimum.

✓ DSD Contractor

CM3 Construction traffic (land and sea) including construction plant, construction vessels and barges should be kept to a practical minimum.

✓ DSD Contractor

CM4 Erection of decorative mesh screens or construction hoardings and/or temporary noise barriers around works areas in visually unobtrusive colours.

✓ DSD Contractor

CM5 Avoidance of excessive height and bulk of site

buildings and structures.

✓ DSD Design Engineer

CM6 Control of night-time lighting by hooding all

lights and through minimisation of night

working periods.

✓ DSD Contractor

CM7 All existing trees shall be carefully protected

during construction. A Detailed Tree

Protection Specification shall be provided in

the Contract Specification. Under this

specification, the Contractor shall be required

to submit, for approval, a detailed working

method statement for the protection of trees

prior to undertaking any works adjacent to all

retained trees, including trees in contractor’s

works areas. Tree risk assessment shall be

undertaken to all existing trees within the

project site as per “Guidelines for Tree Risk

Assessment and Management Arrangement”.

✓ DSD Contractor

CM8 Protective materials to be provided to natural

rocky coastline to prevent damage to existing

landform from plant and machinery during

temporary drilling operations. Reinstatement

following removal of plant & equipment to

original or improved condition shall be

undertaken.

✓ DSD Contractor






Table 10-7: Proposed Operation Phase Landscape and Visual Mitigation

Measures

ID

No.

Landscape and Visual

Mitigation Measure

Landscape

Measure

Visual

Measure

Funding

Agency

Implementation

Agency

Management

Agency

Maintenance

Agency

OM1 Sensitive design of sewage

treatment plant in terms of

scale, height and bulk

(visual weight) to integrate

the building into the

existing topography.

✓ DSD Design

Architect/

Engineer

DSD Building

Operator

OM2 Use of appropriate building

materials and colours for

sewage treatment plant to

complement surroundings*

✓ DSD Design

Architect/

Engineer

DSD Building

Operator

OM3 Lighting units to be

directional and minimise

unnecessary light spill and

glare.

✓ DSD Design

Architect/

Engineer

DSD Building

Operator

OM4 Greening measures to

reinstate the landscape

which are appropriate to the

context, including tree and

shrub planting and vertical

greening, shall be

implemented.

✓ ✓ DSD Contractor DSD Building

Operator

OM5 Compensatory tree planting

for all felled trees shall be

provided to the satisfaction

of relevant Government

departments. Required

numbers and locations of

compensatory trees shall be

determined and agreed

separately with

Government during the

Tree Felling Application

process under the relevant

technical circulars. Tree

risk assessment shall be

undertaken to all existing

trees within the project site

as per “Guidelines for Tree

Risk Assessment and

Management

Arrangement”.

Planting at Sewage

Treatment Plant

Planting at temporary

drilling site for Submarine

Outfall

✓ ✓

DSD

DSD

Contractor

Contractor

DSD

DSD

DSD/Building

Operator

DSD

* Appropriate building materials and colours include use of non-reflective finishes such as textured render for

the building and recessive colours that blend with the natural tones of the landscape backdrop (refer to Figure

10.14 for preliminary design intent).






Programme of Implementation of Landscape and Visual Mitigation Measures

(e) The construction phase measures listed above shall be adopted from the

commencement of construction and shall be in place throughout the entire

construction period. The operation phase measures listed above shall be

adopted during the detailed design, and be built as part of the construction

works so that they are in place at the date of commissioning of the Proposed

Project. However, it should be noted that the full effect of the soft landscape

mitigation measures would not be appreciated for several years.

10.6.5 Prediction of Significance of Landscape Impacts

(a) The potential significance of the landscape impacts during the construction and

operation phases, before and after mitigation, are provided below in Table 10-

8 and the residual impact significance after 10 years is mapped on Figure

10.11. This assessment follows the methodology outlined in Section 10.4

above and assumes that the appropriate mitigation measures identified in Table

10-6 and Table 10-7 above will be implemented, and that the full effect of the

soft landscape mitigation measures will be realised after 10 years.

Photomontages of the proposed development before and after mitigation are

provided in Figures 10.14 to 10.18 inclusive.

Construction Phase before Mitigation

(a) During the construction phase, before the implementation of the proposed

mitigation measures, there will be some adverse landscape impacts as

summarised below and identified in Table 10-8.

Landscape Resources

(a) LR1, (Coastal Waters) would experience impacts of Moderate significance

before mitigation due to the dredging works associated with the construction of

the submarine outfall.

(b) LR2, (Streams) would experience an impact significance of None due to the

absence of any impacts.

(c) LR3, (Natural Rocky Coastline) would experience impacts of Moderate

significance before mitigation due to the temporary drilling rig and plant

associated with the construction of the submarine outfall.

(d) LR4, (Natural Coastal Upland Vegetation) would experience impacts of

Slight significance due to the construction works on the site of the sewage

treatment plant.

(e) LR5, (Domestic Amenity Tree and Shrub Planting) would experience an

impact significance of None due to the absence of any impacts.






(f) LR6, (Amenity Grass Areas) would experience an impact significance of

None due to the absence of any impacts.

(g) LR7, (Artificial Ponds) would experience an impact significance of None due

to the absence of any impacts.


(a) LCA1 (Coastal Upland and Hillside Landscape) would experience

Moderate impact significance due to the loss of 0.089 ha of the character area

caused by construction of the sewage treatment plant.

(b) LCA2 (Bay Landscape) would experience Moderate impact significance due

to the dredging works (approximately 0.12 ha) associated with the construction

of the submarine outfall.

(c) LCA3 (Intertidal Bay Landscape) would experience an impact significance

of None.

(d) LCA4 (Coastal Village Landscape) would experience Slight impact

significance due to the construction of the sewer and rising mains along

existing paved roads and footpaths within the village and temporary drilling

works (0.032 ha).

(e) LCA5 (Golf Course Landscape) would experience an impact significance of

None.

Construction Phase After Mitigation

(a) During the construction phase after mitigation, the landscape impacts would

only be slightly less than before mitigation as the mitigation measures are not

sufficient to reduce the impact significance threshold.

Landscape Resources

(a) LR1 (Coastal Waters) and LR3 (Natural Rocky Coastline) would continue

to experience temporary landscape impacts of Moderate significance and LR4

(Natural Coastal Upland Vegetation) would continue to experience impacts

of Slight significance. The remaining Landscape Resources (LR2, LR5, LR6

and LR7) would experience no impacts.


(a) LCA1 (Coastal Upland and Hillside Landscape) and LCA2 (Bay

Landscape) would continue to experience temporary landscape impacts of

Moderate significance and LCA4 (Coastal Village Landscape) would






continue to experience impacts of Slight significance. The remaining

Landscape Character Areas (LCA3 and LCA5) would experience no impacts.

Operation Phase before Mitigation

(a) In the operation phase, before the implementation of the proposed mitigation

measures, there would be some adverse landscape impacts as summarised

below and identified in Table 10-8.

Landscape Resources

(a) LR1 (Coastal Waters) would experience an impact significance of None due

to the absence of any impact caused by the submarine cable.

(b) LR2 (Streams) would experience an impact significance of None.

(c) LR3 (Natural Rocky Coastline) would experience an impact significance of

Slight due to the disturbance caused by the on shore works area.

(d) LR4 (Natural Coastal Upland Vegetation) would experience an impact

significance of Slight as without mitigation, the loss of vegetation would not

be compensated.

(e) LR5 (Domestic Amenity Tree and Shrub Planting) would experience an

impact significance of None due to the absence of any impacts.

(f) LR6 (Amenity Grass Areas) would experience an impact significance of

None due to the absence of any impacts.

(g) LR7 (Artificial Ponds) would experience an impact significance of None due

to the absence of any impacts.


(a) LCA1 (Coastal Upland and Hillside Landscape) would experience an

impact significance of Moderate due to the impacts of the sewage treatment

plant.

(b) LCA2 (Bay Landscape) would experience an impact significance of None

during the operation stage before mitigation due to the absence of impacts

caused by the submarine outfall.

(c) LCA3 (Intertidal Bay Landscape) would experience and impact significance

of None during the operation stage before mitigation due to the absence of

impacts.






(d) LCA4 (Coastal Village Landscape) would experience and impact

significance of Slight during the operation stage before mitigation due to the

disturbance caused to existing roads and footpaths.

(e) LCA5 (Golf Course Landscape) would experience and impact significance of

None during the operation stage before mitigation due to the absence of

impacts.

Operation Phase after Mitigation

(a) In the operation phase, after the implementation of the proposed mitigation

measures, there will be some adverse residual landscape impacts as

summarised below and identified in Table 10-8.

(b) Implementation of the recommended mitigation measures will reduce the

magnitude of the residual landscape impacts during the operation phase, and in

some cases this will be sufficient to reduce the overall significance thresholds

described above for the before mitigation scenario.

Landscape Resources

(a) For LR4 (Natural Coastal Upland Vegetation) the impact significance would

remain as Slight at Day 1 and reduce to Insubstantial at Year 10 due to the

effects of maturing compensatory tree planting and greening of the sewage

treatment plant.

(b) For LR3 (Natural Rocky Coastline) the impact significance following the

reinstatement of the foreshore will be Insubstantial at Day 1 due to the

infilling of any excavations and replacement of the rocky surface and

compensatory planting with very little noticeable change from the existing

condition. By Year 10 once compensatory planting has fully matured and

natural recolonization has occurred, the impact significance will be None.

(c) For all the remaining LRs, (LR1, LR2, LR6 and LR7) the impact significance

will be None during the operation stage.


(a) For LCA1 (Coastal Upland and Hillside Landscape) the impact significance

would be reduced from Moderate to Slight at Day 1 following mitigation due

to compensatory tree planting and building greening. This would be further

reduced to Insubstantial at year 10 due to the maturing of the vegetation.

(b) LCA4 (Coastal Village Landscape) will experience an impact significance of

Insubstantial significance at Day 1 and Year 10 as the pipeline trench covers

will be integrated with the existing roads and footpaths.






(c) For all the remaining LCAs, (LCA2, LCA3 and LCA5) the impact

significance will be None during the operation stage at Day 1 and Year 10.






Table 10-8: Significance of Landscape Impacts in Construction and Operation Phases (Adverse Impacts unless otherwise stated)

Id.

No.

Landscape Resource /

Landscape Character

Sensitivity to

Change during

Construction

and Operation

Phases

(Low, Medium,

High)

Magnitude of Change before

Mitigation (None, Negligible,

Small, Intermediate, Large)

Impact Significance

Threshold BEFORE

Mitigation

(None, Insubstantial, Slight,

Moderate, Substantial)

Recommen

ded

Mitigation

Measures

Residual Impact Significance Threshold

AFTER Mitigation

(None, Insubstantial, Slight, Moderate,

Substantial)

Construction Operation

Construction Operation Construction Operation DAY 1 YEAR 10

Landscape Resources

LR1 Coastal Waters Medium Small None Moderate None CM1 Moderate None None

LR2 Streams Medium None None None None N/A None None None

LR3 Natural Rocky

Coastline Medium Small Small Moderate Slight

CM1,7 & 8

OM5 Moderate Insubstantial None

LR4 Natural Coastal Upland

Vegetation High Small Small Slight Slight

CM1 & 7

OM4 & 5 Slight Slight Insubstantial

LR5 Domestic Amenity Tree

& Shrub Planting Low None None None None N/A None None None

LR6 Amenity Grass Areas Low None None None None N/A None None None

LR7 Artificial Ponds Low None None None None N/A None None None


LCA1 Coastal Upland &

Hillside Landscape High Small Small Moderate Moderate

CM1 & 7

OM4 & 5 Moderate Slight Insubstantial

LCA2 Bay Landscape High Small None Moderate None CM1 Moderate None None

LCA3 Intertidal Bay

Landscape High None None None None N/A None None None

LCA4 Coastal Village

Landscape Medium Small Small Slight Slight CM1,7 & 8 Slight Insubstantial Insubstantial

LCA5 Golf Course Landscape Low None None None None N/A None None None






10.7 Visual Impact Assessment

10.7.1 Potential Sources of Visual Impacts

The sources of visual impacts of the Project during construction and operation phases

have been described in Section 10.6.1.

10.7.2 Visual Change Before Mitigation in the Construction and Operation Phase

The magnitude of visual change resulting from the construction and operation phases

of the Proposed Project is presented in Table 10-9 and is summarised for the VSRs

below.

(a) Residents of Po Toi O Village (RES-1) will have partial views of the

temporary construction works associated with the submarine outfall and

sewage treatment plant. Due to their relative distance and the availability of

alternative views, the magnitude of visual change is assessed as ‘Small’. The

magnitude of visual change prior to mitigation during the operation phase will

be ‘Small’ as the submarine outfall will be concealed and the plant and

equipment on the shoreline will have been removed but the shoreline will

remain disturbed. The sewage treatment plant will only be visible by some of

the residents in Po Toi O in upper floors of village houses due to existing

vegetation screens.

(b) Residents of Tai Wong Kung (RES-2) and Cala d’Or (RES-3) will have

partial views of the temporary construction works associated with the

submarine outfall and the sewage treatment plant. Due to their relative

distance and the availability of alternative views, the magnitude of visual

change is assessed as ‘Small’. During the operation phase, views of the

submarine outfall will disappear but views of the disturbed foreshore and

completed sewage treatment plant will remain. The magnitude of visual

change is assessed as ‘Small’ prior to mitigation.

(c) Residents of Fairway Vista (RES-4) will have elevated views of the

temporary construction works associated with the submarine outfall only (the

sewage treatment plant will not be visible). The magnitude of visual change

prior to mitigation is assessed as ‘Intermediate’ during the construction phase

due to the proximity of view (worst case 50m) and the screening effect of

existing vegetation. The magnitude of visual change during the operation

phase will be ‘Small’ as the submarine outfall will be concealed and the plant

and equipment on the shoreline will have been removed but the shoreline will

remain disturbed with a decrease in tree cover due to clearance during the

construction works.

(d) Residents of Tai Au Mun (RES-5) will have views of the temporary

construction works associated with the submarine outfall only (the sewage

treatment plant will not be visible). The magnitude of visual change prior to

mitigation is assessed as ‘Negligible’ during the construction phase due to the






distance of view and the screening effect of existing vegetation. The

magnitude of visual change during the operation phase prior to mitigation is

assessed as ‘Negligible’ as the submarine outfall will be concealed and the

shoreline construction plant will have been removed. The foreshore will

remain disturbed prior to mitigation, but the degree of visibility to residents at

RES-5 is likely to be very limited due to the distance of view.

(e) Hikers on Tin Ha Shan (REC-1) will have elevated views of the temporary

construction works associated with the submarine outfall and the sewage

treatment plant. Due to their relative distance and the availability of alternative

views, the magnitude of visual change is assessed as ‘Small’. During the

operation phase, views of the submarine outfall will disappear but views of the

disturbed foreshore and the completed sewage treatment plant will remain.

The magnitude of visual change is assessed as ‘Small’ prior to mitigation.

(f) Recreational Craft in Clear Water Bay (REC-5) will have views of the



prior to mitigation is assessed as ‘Intermediate’ during the construction phase

as there are abundant alternative views and marine craft (ie. the barges) are to

be expected in the context. The magnitude of visual change during the

operation phase prior to mitigation is assessed as ‘Negligible’ as the temporary

cofferdam and barges will have gone and the submarine outfall will be

concealed and the shoreline construction plant will have been removed.

However, the foreshore will remain disturbed prior to mitigation with a

reduction in tree cover due to clearance during construction and may be visible

from recreational craft.

(g) Visitors to Seafood restaurants in Po Toi O (REC-6) will potentially have

distant views of the temporary construction works associated with the

submarine outfall but not of the sewage treatment plant. As the views are

short-lived and the focus of the visitors is within the restaurants, the magnitude

of visual change is assessed as ‘Small’. The magnitude of visual change prior

to mitigation during the operation phase will be ‘Negligible’ as the submarine

outfall will be concealed but the shoreline will remain disturbed.

(h) Players on Clear Water Bay Golf Course (REC-2) will have partial views of

the temporary construction works associated with the submarine outfall and the

sewage treatment plant. Due to their relative distance, partial screening by

existing vegetation, the availability of alternative views and their visual focus

on views within the course, the magnitude of visual change is assessed as

‘Small’. During the operation phase, views of the submarine outfall

construction works will have gone but views of the disturbed foreshore and the

completed sewage treatment plant will remain. The magnitude of visual

change is assessed as ‘Small’ prior to mitigation.

(i) All the other Recreational VSRs, Visitors to Clear Water Bay Country Park

Visitor Center (REC-3), Hikers on Tai Leng Tung (REC-4), Hikers at

High Junk Peak (REC-7), Users of Clear Water Bay First Beach (REC-8)






will have views of the temporary construction works associated with the

submarine outfall only (the sewage treatment plant will not be visible). The

magnitude of visual change prior to mitigation is assessed as ‘Negligible’

during the construction phase primarily due to the distance of view and because

the main visual impact, namely the marine craft are to be expected in the

marine context. The magnitude of visual change prior to mitigation during the

operation phase is ‘Negligible’ as the submarine outfall will be concealed and

although the shoreline will remain disturbed, the degree of visibility from such

distances will be very limited.

(j) Users of Clear Water Bay Second Beach (REC-9) will have views of the



prior to mitigation is assessed as ‘Negligible’ during the construction phase

primarily due to the distance of view and because the main visual impact,

namely the marine craft are to be expected in the marine context. The

magnitude of visual change prior to mitigation during the operation phase is

‘None’ as the submarine outfall will be concealed and the disturbed shoreline is

screened from view by a headland.

(k) Drivers and Passengers along Po Toi O Chuen Road (T-2) will have views

of the temporary construction works associated with the submarine outfall and

the sewage treatment plant during the construction stage. The views will be

short-lived and the focus of the drivers/passengers is on the road. However,

the proximity of the road to the sewage treatment plant results in an assessment

of the magnitude of visual change as ‘Large’. During the operation phase,

views of the submarine outfall will disappear but views of the completed

sewage treatment plant will remain. The magnitude of visual change is

assessed as ‘Large’ prior to mitigation.

(l) Drivers and Passengers along Tai Au Mun Road (T-1a) will have elevated

views of the temporary construction works associated with the submarine

outfall and the sewage treatment plant. As the views are short-lived and the

focus of the drivers/passengers is on the road, the magnitude of visual change

is assessed as ‘Small’. During the operation phase, views of the submarine

outfall will disappear but views of the disturbed foreshore and the completed

sewage treatment plant will remain. The magnitude of visual change is

assessed as ‘Small’ prior to mitigation.

(m) Drivers and Passengers along Tai Au Mun Road (T-1b) will have distant

views of the temporary construction works associated with the submarine

outfall but not of the sewage treatment plant. As the views are short-lived and

the focus of the drivers/passengers is on the road, the magnitude of visual

change is assessed as ‘Negligible’. The magnitude of visual change during the

operation phase is ‘None’ as the submarine outfall will be concealed and

although the disturbed shoreline construction worksite will not be visible due

to an intervening headland.






(n) Drivers and Passengers along Clear Water Bay Road to Tai Hang Tau (T-

3) will have distant views of the temporary construction works associated with

the submarine outfall but not of the sewage treatment plant. As the views are

short-lived and the focus of the drivers/passengers is on the road, the

magnitude of visual change is assessed as ‘Negligible’. The magnitude of

visual change during the operation phase is ‘Negligible’ as the submarine

outfall will be concealed and although the shoreline construction worksite will

remain disturbed, the degree of visibility will be limited from such distances.

(o) Fishermen in Po Toi O (O-1) will have views of the temporary construction

works associated with the submarine outfall and the sewage treatment plant.

As the focus of the fishermen is on their work rather than the scenery and there

are abundant alternative views, the magnitude of visual change is assessed as

‘Small’. During the operation phase, views of the submarine outfall will

disappear but views of the disturbed shoreline and the completed sewage

treatment plant will remain. The magnitude of visual change is assessed as

‘Small’ prior to mitigation.

(p) Workers in Seafood Restaurants in Po Toi O (O-3) will potentially have

distant views of the temporary construction works associated with the


short-lived and the focus of the workers is within the restaurant, the magnitude

of visual change is assessed as ‘Small’. The magnitude of visual change

during the operation phase is ‘Negligible’ as the submarine outfall will be

concealed and the disturbed shoreline construction worksite will be barely

visible.

(q) Workers and Staff at Clear Water Bay Country Park Visitor Centre (O-2) will have distant views of the temporary construction works associated with the


distant, the magnitude of visual change is assessed as ‘Negligible’. The

magnitude of visual change prior to mitigation during the operation phase is

‘Negligible’ as the submarine outfall will be concealed and the disturbance to

the shoreline construction worksite will not be visible from such a distance.

10.7.3 Proposed Landscape and Visual Mitigation Measures

The proposed landscape and visual mitigation measures for impacts from the

construction and operation phases are described previously in Table 10-6 and Table

10-7, together with the associated funding, implementation, management and

maintenance agencies and the proposed implementation programme.

10.7.4 Photomontage Viewpoints

(a) The photomontage viewpoints were selected as representative examples of the

visual impacts of the Project. Viewpoints have been selected to provide close,

medium and long range views of the Project. The locations of the viewpoints

are indicated on Figures 10.9 and 10.10. Figures 10.14 to 10.16 show

‘Existing Baseline Conditions’ in November 2014 and photomontages of the






completed sewage treatment plant at ‘Day 1 Without Mitigation Measures’,

‘Day 1 With Mitigation Measures’ and ‘Year 10 With Mitigation Measures

(the construction stage of the sewage treatment plant is not illustrated). As

some viewpoints will have no views of the sewage treatment plant and only

temporary views of the submarine outfall during construction, Figures 10.17

and 10.18 show ‘Existing Baseline Conditions’ in November 2014 and the

submarine outfall ‘During Construction Without Mitigation Measures’,

‘During Construction with Mitigation Measures’ and ‘Day 1 and Year 10 with

Mitigation Measures’.

P1 - Viewpoint from Po Toi O Chuen Road looking south: this viewpoint

was selected as representative of views from residents at Po Toi O (RES-1) and

drivers and passengers, (VSR T-2) as it provides direct views of the sewage

treatment plant. The viewpoint is located on Po Toi O Chuen Road north of

the sewage treatment plant at an elevation of approximately 10 mPD.

P2 - Viewpoint from Tai Au Mun Road looking east: this viewpoint was

selected as representative of views from drivers and passengers, (VSR T-1a) as

it provides elevated direct views across Po Toi O of the sewage treatment plant.

The viewpoint is located on Tai Au Mun Road west of the sewage treatment

plant at an elevation of approximately 60 mPD.

P3 - Viewpoint from Tin Ha Shan looking east: this viewpoint was selected

as representative of views from hikers at Tin Ha Shan (REC-1) as it provides

elevated direct views across Po Toi O of the sewage treatment plant. The

viewpoint is located on the upper eastern slopes of Tin Ha Shan on the public

hiking trail at an elevation of approximately 220 mPD.

P4 – Viewpoint from Clear Water Bay Country Park Visitor Centre: this

viewpoint was selected as representative of views from visitors to Clear Water

Bay Country Park Visitor Centre (REC-3) and it provides elevated direct views

south across Clear Water Bay towards Po Toi O. The dredging activities for the

submarine outfall will be temporarily visible from this viewpoint during

construction. The viewpoint is located on the southern slopes of Tai Hang Tun

within the Country Park facilities at an elevation of approximately 105 mPD.

P5 – Viewpoint from Clear Water Bay Second Beach Looking South East:

this viewpoint was selected as representative of views from users of the

swimming beaches on the western side of Clear Water Bay (REC-9) and

provides low level views south east across the bay towards the location of the

Submarine Outfall. The viewpoint is located towards the northern end of the

Second Beach close to sea level.






Table 10-9: Magnitude of Visual Change during the Construction and Operation Phases before Mitigation

VSR ID

Key VSR

Compatibility

of the Project

with the

Visual

Backdrop

(High/Medium

/Low)

Duration and Frequency of

Impacts

(Temporary/Permanent &

Intermittent/Continuous)

Scale of

Development (Large/Mediu

m/Small) &

Reversibility

of Change (Yes/No)

Degree of Visibility of Source(s)

of Visual Impact (Full, Partial,

Obscured) & Distance Between

VSR & Nearest Source(s) of

Impact

Potential Blockage of Existing

View

(Full/Partial/Slight/Negligible)

Magnitude of Visual

Change BEFORE

Mitigation

Construction Operation Construction Operation Construction Operation Construction Operation

Residential VSRs

RES-1 Residents of Po Toi O

Village Medium

Permanent,

Continuous

Permanent,

Continuous Small, No Partial, 250m Partial, 250m Partial Negligible Small Small

RES-2 Residents of Tai Wong

Kung Medium

Permanent,

Continuous

Permanent,

Continuous Small, No Partial, 500m Partial, 500m Negligible Negligible Small Small

RES-3 Residents of Cala d’Or Medium Permanent,

Continuous

Permanent,


RES-4 Residents of Fairway

Vista Medium

Permanent,

Continuous

Permanent,

Continuous Small, No Partial, 50m N/A Slight None Intermediate Small

RES-5 Residents at Tai Au

Mun Medium

Temporary,

Intermittent N/A Small, Yes Full, 2000m N/A Negligible None Negligible Negligible

Recreational VSRs

REC-1 Hikers on Tin Ha Shan Medium Permanent,

Continuous

Permanent,


REC-2 Players on Clear Water

Bay Golf Course Medium

Permanent,

Continuous

Permanent,

Continuous Small, No Partial, 500m Partial, 500m Slight Slight Small Small

REC-3

Visitors to Clear Water

Bay Country Park

Visitor Centre

Medium Temporary,

Intermittent N/A Small, Yes Full , 1300m N/A Negligible None Negligible Negligible

REC-4 Hikers on Tai Leng

Tung Medium

Temporary,

Intermittent N/A Small, Yes Full , 2000m N/A Negligible None Negligible Negligible

REC-5 Recreational Craft in

Clearwater Bay Medium

Temporary,

Intermittent N/A Small, Yes Full , 25m N/A Partial None Intermediate Negligible

REC-6

Visitors to Seafood

Restaurants in Po Toi

O

Medium Temporary,

Intermittent N/A Small, Yes Partial, 500m N/A Partial None Small Negligible






VSR ID

Key VSR

Compatibility

of the Project

with the

Visual

Backdrop

(High/Medium

/Low)


Impacts



Scale of


m/Small) &

Reversibility

of Change (Yes/No)





Impact


View


Magnitude of Visual

Change BEFORE

Mitigation


REC-7 Hikers at High Junk

Peak Medium

Temporary,


REC-8 Users of Clear Water

Bay First Beach Medium

Temporary,



Bay Second Beach Medium

Temporary,

Intermittent N/A Small, Yes Full, 1500m N/A Negligible None Negligible None

Travelling VSRs

T-1a

Drivers & Passengers

along Tai Au Mun

Road

Medium Permanent,

Continuous

Permanent,

Intermittent Small, No Full, 500m Full, 500m Negligible Negligible Small Small

T-1b


along Tai Au Mun

Road

Medium Temporary,

Intermittent N/A Small, Yes Full, 1000m N/A Negligible None Negligible None

T-2


along Po Toi O Chuen

Road

Medium Permanent,

Intermittent

Permanent,

Intermittent Small, No Full, ~5m Full, 5m Partial Partial Large Large

T-3


along Clear Water Bay

Road to Tai Hang Tau

Medium Temporary,


Occupational VSRs

O-1 Fishermen in Po Toi O Medium Permanent,

Intermittent

Permanent,

Intermittent Small, No Partial, 25m Partial, 25m Negligible Negligible Small Small

O-2

Workers/Staff at Clear

Water Bay Country

Park Visitor Centre

Medium Temporary,







VSR ID

Key VSR

Compatibility

of the Project

with the

Visual

Backdrop

(High/Medium

/Low)


Impacts



Scale of


m/Small) &

Reversibility

of Change (Yes/No)





Impact


View


Magnitude of Visual

Change BEFORE

Mitigation


O-3

Workers in Seafood


O

Medium Temporary,

Intermittent Temporary Small, Yes Partial, 600 Partial, 600 Partial Partial Small Negligible

Note:

(1) The closest viewing distance has been used to rate the worst case scenario

(2) ‘Permanent’ duration measurement refers to entire construction/operation phase






10.7.5 Prediction of Significance of Visual Impacts

An assessment of the significance of the potential visual impacts during the

construction and operation phases, before and after mitigation, is briefly described,

and listed in detail in Table 10-10 (All impacts are adverse unless otherwise stated).

This follows the methodology outlined in Section 10.4 above and assumes that the

appropriate mitigation measures identified in Table 10-6 and Table 10-7 would be

implemented, and that the full effect of the soft landscape mitigation measures would

be realised after 10 years.

10.7.6 Impacts during the Construction and Operation Phase before and after Mitigation

(a) Due to the small scale and low building height of the sewage treatment plant

and the submerged nature of the sewage outfall, the visual impact significance

for most VSRs during the Construction and Operation Phase, both before and

after mitigation is relatively low. Many of the VSRs are a long distance away

and enjoy good quality views of the sea, mountains and offshore islands and

alternative views are available. The impact upon each VSR is described in

greater detail below. The magnitude of impacts experienced by VSRs is

generally greater in the construction phase than in the operation phase for most

VSRs due to the presence of the construction activities and temporary

disturbance to the landscape. The visual impacts for the submarine outfall and

associated foreshore are mostly only experienced during the construction phase

and are largely absent during the operational phase following mitigation

(except for the residual impact of loss of existing trees which is mitigated

through time with the establishment of compensatory planting).

(b) Photomontages illustrating the existing views, construction and operation

phase impacts before and after the implementation of mitigation measures are

provided in Figures 10.14 to 10.18 and their locations are illustrated on

Figures 10.9 and 10.10. Mitigation measures are described in more detail in

Table 10-6 and Table 10-7.

Residential VSRs

(c) Residents in Po Toi O (RES-1), Tai Wong Kung (RES-2) and Cala d’Or

(RES-3) will have permanent and continuous views towards the source of

visual impact (ie the sewage treatment plant and of the submarine outfall

drilling and dredging site) at varying distances. In the construction phase prior

to mitigation, the magnitude of visual change is ‘Small’, and this combined

with their ‘High’ sensitivity results in an impact of Moderate significance.

This is predicted to remain as Moderate following mitigation as the mitigation

measures will not be able to reduce the visual impact significance threshold. In

the operation phase before mitigation, the impact significance is predicted to

remain as Moderate. Mitigation measures are anticipated to reduce the visual

impact significance to Slight at Day 1 and Insubstantial at Year 10, primarily

due to the absence from view of the submarine outfall, the reinstatement of the






foreshore and the maturing greening and screening measures for the sewage

treatment plant.

(d) Residents at Fairway Vista (RES-4) will potentially have temporary views of

the submarine outfall drilling rig and plant on the foreshore and the outfall

dredging site. The magnitude of change is assessed as ‘Intermediate’ and this

combined with their ‘High’ sensitivity results in an impact significance of

Moderate prior to mitigation. Following mitigation, the visual impacts will

remain as Moderate as the mitigation measures will not be able to reduce the

visual impact significance threshold. During the operation stage, this VSR will

experience Slight visual impacts before mitigation as the temporary

construction plant will have gone, the permanent submarine outfall will be

concealed but the foreshore will remain disturbed. Following mitigation, this

VSR will experience Insubstantial visual impacts during the operation phase

as the foreshore will be have been reinstated.

(e) Residents at Tai Au Mun (RES-5) will potentially have temporary views of

the dredging activity and submarine outfall drilling rig and plant on the

foreshore during the construction stage. The magnitude of change is assessed

as ‘Negligible’ (due primarily to the distance of view) and this combined with

their ‘High’ sensitivity results in an impact significance of Insubstantial.

Following mitigation, the visual impacts will remain as Insubstantial as the

mitigation measures will not be able to reduce the visual impact significance

threshold. This VSR will experience Insubstantial visual impacts during the

operation phase as the temporary construction plant will have gone, the

permanent submarine outfall is concealed and the disturbed foreshore will be

have been reinstated.

Recreational VSRs

(a) Hikers on Tin Ha Shan (REC-1) will potentially have temporary views of the

sewage treatment plant, outfall drilling rig plant and dredging operation during

construction. The magnitude of change is assessed as ‘Small’ and this

combined with their ‘High’ sensitivity results in an impact significance of

Moderate before mitigation. Following mitigation, the visual impacts will


visual impact significance threshold. During the operation stage, the VSRs will

have views of the sewage treatment plant and will experience Moderate

residual visual impact before mitigation. Following mitigation in the operation

phase, the impact significance will reduce to Slight at Day 1 due to the absence

of impacts at the submarine outfall and the mitigation measures installed at the

sewage treatment plant. The impact significance will reduce to Insubstantial

by Year 10 as the greening measures at the sewage treatment plant reach

maturity.

(b) Recreational Craft in Clear Water Bay (REC-5) will potentially have

temporary views of the submarine outfall drilling rig plant and outfall dredging






operation during the construction stage. The magnitude of change is assessed

as ‘Intermediate’ and this combined with their ‘High’ sensitivity results in an

impact significance of Moderate. Following mitigation, the visual impacts will


visual impact significance threshold. This VSR will experience Insubstantial

visual impacts during the operation phase before mitigation as the temporary

construction plant will have gone and the permanent submarine outfall is

concealed. Following mitigation, the visual impacts will remain as

Insubstantial as the disturbed foreshore will be have been reinstated.

(c) Visitors to Seafood Restaurants in Po Toi O (REC-6) will have views of the

submarine outfall drilling rig, plant and dredging operation on the foreshore

during construction but no views of the sewage treatment plant. The magnitude

of change during construction is assessed as ‘Small’ and this combined with

their ‘Medium’ sensitivity results in an impact significance of Slight.

Following mitigation, the visual impacts will remain as Slight as the mitigation

measures will not be able to reduce the visual impact significance threshold.

During the operation stage this VSR will experience Insubstantial visual

impacts during the operation phase prior to mitigation as the temporary

construction plant will have gone, the permanent submarine outfall will be

concealed but the foreshore will remain disturbed. Following mitigation, and

the foreshore will be have been reinstated and the visual impacts will remain as

Insubstantial and will gradually decline as the compensatory tree planting

matures.

(d) Players on Clear Water Bay Golf Course (REC-2) will potentially have

temporary views of the sewage treatment plant, outfall drilling rig plant and

outfall dredging operation during the construction stage. The magnitude of

change is assessed as ‘Small’ and this combined with their ‘Medium’

sensitivity results in an impact significance of Slight prior to mitigation.

Following mitigation, the visual impacts will remain as Slight as the mitigation

measures will not be able to reduce the visual impact significance threshold. In

the operation phase, the predicted impact significance is predicted to be Slight

prior to mitigation. Following mitigation, this will be reduced to Insubstantial

at Day 1 and will remain as Insubstantial by Year 10.

(e) All the remaining VSRs (REC-3, REC-4, REC-7 to REC-8 inclusive) will

experience impacts of Insubstantial significance during the construction phase

prior to mitigation. This will remain as Insubstantial following mitigation as

the mitigation measures will not be able to reduce the visual impact

significance threshold. During the operational phase, all these VSRs will

experience Insubstantial visual impacts after mitigation at Day 1 and Year 10

as the temporary construction plant will have gone, the permanent submarine

outfall is concealed and the foreshore will be have been reinstated.

(f) REC-9 will experience impacts of Insubstantial significance during the

construction phase prior to mitigation. This will remain as Insubstantial

following mitigation as the mitigation measures will not be able to reduce the

visual impact significance threshold. During the operational phase, this VSR






will experience no visual impacts as the only previously visible elements,

namely the barges and the cofferdam will have gone. The disturbed foreshore

is not visible from this VSR as it is screened by a headland.

Travelling VSRs

(a) Drivers and Passengers along Po Toi O Chuen Road (T2): will have distant

temporary views of the submarine outfall dredging operation during

construction and close-up views of the sewage treatment plant construction

site. In the construction phase prior to mitigation, the resultant magnitude of

visual change with regard to the sewage treatment plant is ‘Large’, and this

combined with their ‘Medium’ sensitivity results in an impact considered to be

of Substantial significance. This will remain as Substantial following

mitigation as the mitigation measures will not be able to reduce the visual

impact significance threshold. In the operation phase before mitigation, the

impact significance will remain as Substantial due to the visual impacts of the

sewage treatment plant (the submarine outfall will be concealed and the

associated construction plant will have gone). Following mitigation the impact

significance will be reduced to Moderate at Day 1 due to the screening,

planting and chromatic treatment and Slight at Year 10 due to the maturing

effects of the vegetation.

(b) Drivers and Passengers along Tai Au Mun Road (T-1a) will experience a

‘Small’ magnitude of change due to the construction of the sewage treatment

plant and the temporary construction works of the submarine outfall and

combined with their ‘Medium’ sensitivity the resultant impact significance is

Slight during the construction phase prior to mitigation. This will remain as

Slight following mitigation as the mitigation measures will not be able to

reduce the visual impact significance threshold. In the operation phase before

mitigation, the impact significance will remain as Slight. Following mitigation

the impact significance will be Slight at Day 1 due to the screening, planting

and chromatic treatment and Insubstantial at Year 10 due to the maturing

effects of the vegetation.

(c) Drivers and Passengers further along Tai Au Mun Road (T-1b) will

experience a ‘Negligible’ magnitude of visual change (primarily due to

distance) and combined with the ‘Medium’ sensitivity the resultant impact

significance is Insubstantial during the construction phase both before and

after mitigation. During the operation phase they will have no views of the

permanent works and the visual impact significance at Day 1 and Year 10 will

therefore be None.

(d) Drivers and Passengers further along Clear Water Bay Road (T3) will

experience a ‘Negligible’ magnitude of visual change (primarily due to

distance) and combined with the ‘Medium’ sensitivity the resultant impact

significance is Insubstantial during the construction phase both before and

after mitigation. During the operation phase they will experience a negligible

magnitude of change due to the disturbed foreshore (primarily due to the great






distance of view) and the visual impact significance at Day 1 and Year 10 will

therefore be Insubstantial.

Occupational VSRs

(a) Fishermen in Po Toi O (O-1) will experience a ‘Small’ magnitude of visual

change and combined with the ‘Low’ sensitivity, the resultant impact

significance will be Slight during construction both before and after mitigation.

During the operation phase before mitigation, the visual impact significance

would be Slight and this would remain as Slight at Day 1 following mitigation

but would reduce to Insubstantial by Year 10 as the greening measures at the

sewage treatment plant mature.

(b) Workers and Staff at Clear Water Bay Country Park Visitor Centre (O-2) will experience a ‘Negligible’ magnitude of change, primarily due to the

distance from the source of impacts. Combined with their ‘Low’ sensitivity, the

resultant impact significance will be Insubstantial during the construction

phase both before and after mitigation. During the operation phase before

mitigation the submarine outfall will be submerged and these VSRs will

experience a negligible magnitude of change due to the disturbed foreshore

(due primarily to the distance of view). The residual visual impact significance

at Day 1 and Year 10 will remain as Insubstantial.

(c) Workers in Sea Food Restaurants in Po Toi O (O-3) will experience a

‘Small’ magnitude of change, primarily due to the distance from the source of

impacts. Combined with their ‘Low’ sensitivity, the resultant impact

significance will be Slight during the construction phase both before and after

mitigation. During the operation phase they will have no views of the

permanent sewage treatment plant works and the submarine outfall will be

submerged and the magnitude of change from the foreshore disturbance will be

Negligible. The visual impact significance at Day 1 and Year 10 will therefore

be Insubstantial.

10.7.7 Residual Impacts during the Construction Phase after Mitigation

Although implementation of the recommended mitigation measures should slightly

reduce the magnitude of the residual visual impacts during the construction phase,

this will not be sufficient to reduce the overall significance thresholds described

above for the before mitigation scenario.






10.7.8 Residual Impacts during the Operation Phase after Mitigation

(a) Many VSRs will only have temporary views of the construction of the

submarine outfall. During the operation phase when the outfall is concealed

they will experience insubstantial permanent visual impacts.

(b) VSRs with views of the sewage treatment plant and pipeline trenches will

experience temporary views during construction and permanent views during

the operation phase. Mitigation measures including sensitive building design

and chromatic treatment will help reduce the visual impact and the maturing of

compensatory tree planting and building greening measures will reduce the

overall visual impact from Day 1 to Year 10.

(c) Drivers and Passengers along Po Toi O Chuen Road (T-2) will experience

visual impacts of Moderate significance at Day 1 after mitigation. These are

predicted to reduce to Slight by Year 10 due to the maturing planting works.

(d) RES-1, RES-2, RES-3 REC-1, T-1a and O-1 will experience visual impacts

of Slight significance at Day 1 after the implementation of mitigation

measures. These are predicted to reduce to Insubstantial by Year 10 due to the

maturing planting works.

(e) All other VSRs will experience Insubstantial or no visual impacts at Day 1

and Year 10 of the operation phase.






Table 10-10: Significance of Visual Impacts in the Construction and Operation Phases

VSR Type

& ID.

Key Visually Sensitive

Receiver (VSR)

Magnitude of Visual Change

before Mitigation

(None, Negligible, Small,

Intermediate, Large)

Receptor Sensitivity &

Number

(Low, Medium, High) (Very

Few, Few, Many, Very Many)

Impact Significance

Threshold BEFORE

Mitigation



Recommende

d Mitigation

Measures


AFTER Mitigation


Substantial)


Construction Operation Construction Operation Construction Operation DAY 1 YEAR 10

Residential VSRs

RES-1 Residents in Po Toi O

Village Small Small High, Few High, Few Moderate Moderate

CM1- 6

OM1- 6 Moderate Slight Insubstantial

RES-2 Residents at Tai Wong

Kung Small Small High, Few High, Few Moderate Moderate

CM1- 6


RES-3 Residents of Cala d’Or Small Small High, Few High, Few Moderate Moderate CM1- 6


RES-4 Residents of Fairway

Vista Intermediate Small High, Few High, Few Moderate Slight

CM1- 6

OM1- 6 Moderate Insubstantial Insubstantial

RES-5 Residents at Tai Au

Mun Negligible Negligible High, Few High, Few Insubstantial Insubstantial

CM1- 6

OM1- 6 Insubstantial Insubstantial Insubstantial

Recreational VSRs

REC-1 Hikers on Tin Ha Shan Small Small High, Few High, Few Moderate Moderate CM1- 6


REC-2 Players in Clear Water

Bay Golf Course Small Small Medium, Few

Medium,

Few Slight Slight

CM1- 6

OM1- 6 Slight Insubstantial Insubstantial

REC-3

Visitors to Clear Water

Bay Country Park

Visitor Centre

Negligible Negligible High, Many High, Many Insubstantial Insubstantial CM1- 6

OM1- 6 Insubstantial Insubstantial Insubstantial






VSR Type

& ID.


Receiver (VSR)


before Mitigation




Number



Impact Significance

Threshold BEFORE

Mitigation



Recommende

d Mitigation

Measures


AFTER Mitigation


Substantial)



REC-4 Hikers on Tai Leng

Tung Negligible Negligible High, Few High, Few Insubstantial Insubstantial CM1- 6 Insubstantial Insubstantial Insubstantial

REC-5 Recreational Craft in

Clear Water Bay Intermediate Negligible High, Many High, Many Moderate Insubstantial CM1- 6 Moderate Insubstantial Insubstantial

REC-6

Visitors to Seafood


O

Small Negligible Medium, Many Medium,

Many Slight Insubstantial

CM1- 6

OM1- 6 Slight Insubstantial Insubstantial

REC-7 Hikers at Junk Peak Negligible Negligible High, Few High, Few Insubstantial Insubstantial CM1- 6 Insubstantial Insubstantial Insubstantial


Bay First Beach Negligible Negligible Medium, Many

Medium,

Many Insubstantial Insubstantial CM1- 6 Insubstantial Insubstantial Insubstantial

REC9 Users of Clear Water

Bay Second Beach Negligible None High, Many High, Many Insubstantial None CM1- 6 Insubstantial None None

Travelling VSRs

T-1a

Drivers/Passengers

along Tai Au Mun

Road

Small Small Medium,

Many

Medium,

Many Slight Slight

CM1- 6

OM1-6 Slight Slight Insubstantial

T-1b

Drivers/Passengers

along Tai Au Mun

Road

Negligible None Medium,

Many

Medium,

Many Insubstantial None

CM1- 6

Insubstantial None None

T-2

Drivers Passengers

along Po Toi O Chuen

Road

Large Large Medium,

Many

Medium,

Many Substantial Substantial

CM1-6

OM1-6 Substantial Moderate Slight






VSR Type

& ID.


Receiver (VSR)


before Mitigation




Number



Impact Significance

Threshold BEFORE

Mitigation



Recommende

d Mitigation

Measures


AFTER Mitigation


Substantial)



T-3

Drivers/Passengers

along Clear Water Bay

Road to Tai Hang Tun

Negligible Negligible Medium,

Many

Medium,

Many Insubstantial Insubstantial

CM1-6

OM1-6 Insubstantial Insubstantial Insubstantial

Occupational VSRs

O-1 Fishermen in Po Toi O Small Small Low, Few Low, Few Slight Slight CM1-6

OM1-6 Slight Slight Insubstantial

O-2

Workers/Staff at Clear

Water Bay Country

Park Visitor Centre

Negligible Negligible Low, Few Low, Few Insubstantial Insubstantial CM1-6

OM1-6 Insubstantial Insubstantial Insubstantial

O-3

Workers in Seafood


O

Small Negligible Low, Few Low, Few Slight Insubstantial CM1-6

OM1-6 Slight Insubstantial Insubstantial






10.8 Cumulative Impacts

10.8.1 There are two planned projects within the Study Area described in Section 10.3.3,

namely:

(a) Construction of a roundabout near the existing minibus stop in Po Toi O; and

(b) Maintenance dredging of Poi Toi O Fish Culture Zone.

10.8.2 There is no definite programme for the above project works and in the absence of

information it is therefore assumed that they will not be carried out concurrently with

the Project. Consequently there are no cumulative landscape and visual impacts that

need to be taken into account in this assessment.

10.9 Environmental Monitoring and Audit

10.9.1 Construction Phase

Monitoring of Design, Construction and Establishment Works

(a) The contractor shall employ a professionally qualified Registered Landscape

Architect (RLA) on the Environmental Team to supervise and monitor the

implementation of construction phase landscape and visual mitigation

measures. The design, implementation and maintenance of landscape and

visual mitigation measures (refer to Table 10-6 and Table 10-7) shall be

checked to ensure that they are fully realised and that any potential conflicts

between the proposed landscape measures and any other project works and

operational requirements are resolved at the earliest possible date and without

compromise to the intention of the mitigation measures.

Design of Landscape and Visual Mitigation Measures

(b) The detailed design of the landscape and visual mitigation measures shall be

undertaken so as to ensure compliance with the measures described in Section

10.6.4.

Site Supervision of Landscape Works

(c) The implementation of the landscape works and tree risk assessment during the

construction phase and establishment works shall be inspected in accordance

with the site audit program.

10.9.2 Operation Phase

Monitoring of Landscape Mitigation Measures

(a) All landscape and visual mitigation measures shall be monitored by a

Registered Landscape Architect engaged by the Contractor in the first year






after construction (a common practice in EIA) to check that intended

mitigation effects are realised. During this period, the Contractor shall take

good care of the planted trees through regular horticultural operation (e.g.

watering and pruning). This can help the trees to establish and have higher

chance of growing to maturity for the intended landscape effect. Subsequently,

the Project Site (described in Section 10.3.1) shall be handed over to the

project proponent (building operator) for future management and maintenance.

10.10 Conclusion

10.10.1 Landscape Impacts

(a) During the construction phase, Coastal Waters (LR1) and Natural Rocky

Coastline (LR3) will experience an impact of Moderate significance before

mitigation due to temporary minor dredging and drilling works during the

construction of the submarine outfall. Residual impacts during the

construction phase after mitigation will remain as Moderate. However, for

LR3, residual impacts will be Slight during the operation phase before

mitigation due to the disturbance caused to the shoreline, Insubstantial at Day

1 following mitigation with the reinstatement of the shoreline and None at

Year 10 following full establishment of compensatory planting. There will be

no residual impacts for LR1 during the operation phase before or after

mitigation as the source of the impacts (temporary dredging, construction plant

and drilling rig) will be removed. Natural Coastal Upland Vegetation (LR4)

will experience Slight impacts during the construction phase before and after

mitigation due to the loss of trees and vegetation at the sewage treatment plant

site. During the operation phase, LR4 will experience Slight residual impacts

before and after mitigation at Day 1. This will reduce to Insubstantial by Year

10 after mitigation due to the maturing of compensatory tree planting and

greening of the building works. All other landscape resources will experience

no landscape impacts during construction and operation, both before and after

mitigation.

(b) Coastal Upland and Hillside Landscape (LCA1) will experience an impact

significance of Moderate during the construction phase both before and after

mitigation due to the construction of the sewage treatment plant. During the

operational phase, the impact significance will be Moderate before mitigation

and Slight at Day 1 after mitigation. This will be reduced to Insubstantial by

Year 10 after mitigation due to the effects of mature compensatory planting.

Bay Landscape (LCA2) will experience Moderate impacts during the

construction phase both before and after mitigation due to temporary

construction impacts of the submarine outfall. However, there will be no

permanent impacts during the Operation Phase. Coastal Village Landscape

(LCA4) will experience Slight impacts during the Construction Phase both

before and after mitigation due to the construction of the sewage mains. During

the operation phase impacts will be Slight before mitigation and reduced to

Insubstantial at Day 1 and Year 10 following mitigation. Intertidal Bay

Landscape (LCA3) and Golf Course Landscape (LCA5) will experience no






landscape impacts during construction and operation, both before and after

mitigation.

10.10.2 Visual Impacts

(a) The primary visual impact of the Project would result from the construction of

the sewage treatment plant, the sewer, the rising mains and the submarine

outfall. The sewage treatment plant will generate temporary and permanent

visual impacts with the permanent condition being mitigated through sensitive

design of the building form, scale and massing which blend it into the existing

topography, appropriate façade treatments, compensatory tree planting and

greening. Due to its relatively low position on the edge of the bay with visual

enclosure provided by the surrounding uplands, the degree of visibility is

relatively restricted. Temporary visual impacts will be generated by the

submarine outfall during the Construction Stage by the drilling rig site and

dredging craft but all these will be removed following completion of the works.

Insubstantial residual visual impacts during the Operation Stage will be

generated by the disturbed foreshore area and these will be mitigated by the

reinstatement works which will gradually reduce the degree of impact as the

compensatory tree planting matures.

(b) The primary visual receivers permanently impacted by the works will be

Drivers and Passengers along Po Toi O Road (T-2) who will experience

impacts of Substantial significance during construction, Moderate

significance at Day 1 and Slight impacts at Year 10 caused by the presence of

the sewage treatment plant. Residents at Po Toi O Village, Tai Wong Kung

and Cala d’Or (RES 1, RES-2 and RES-3), Hikers on Tin Ha Shan (REC-

1), Drivers and Passengers along Tai Au Mun Road (T-1a) and Fishermen

in Po Toi O (O-1) will experience visual impacts of Slight significance at Day

1 and Insubstantial significance at Year 10. All other VSRs will experience

Insubstantial or No residual visual impacts at Day 1 and Year 10.

10.10.3 Overall Conclusion

(a) This Project will have temporary and permanent landscape and visual impacts

on the environment, which are identified and addressed in this EIA with the

aim of avoiding (where practicable) and at the very least, minimising such

impacts to within acceptable levels. There are opportunities, at the Project’s

design, construction and operation stages, for incorporating environmental

mitigation measures into the Project. These include reducing the scale of the

sewage treatment plant and providing sensitive treatments of its external

appearance and associated planting works.

(b) Due to the relatively small scale of the proposed Project, none of the LRs,

LCAs or VSRs will experience substantial residual impacts. The highest

residual impact for Landscape Resources and Landscape Character Areas is

only assessed as Slight on Day 1 and Insubstantial at Year 10 (all the other

LR’s and LCA’s experiencing Insubstantial or No residual impact at Year






10). The highest residual impact for Visually Sensitive Receivers is Moderate

at Day 1 and Slight at Year 10, (all the other VSRs experiencing only Slight or

Insubstantial residual visual impacts at Day 1 and Insubstantial or No

residual visual impacts at Year 10).

(c) Based on the above assessment, it is considered that in accordance with the

criteria and guidelines for evaluating and assessing impacts as stated in Annex

10 and 18 of the TM- EIAO, the overall residual landscape and visual impacts

of the proposed Project are acceptable with mitigation during the construction

and operation phases.

10. LANDSCAPE AND VISUAL IMPACT 10.1 Figure 10

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