Appendix 7.1	Rapid Ecological Assessment
Appendix 7.2	Representative Photographs of Habitat Types Within the Assessment Area of the Proposed Typhoon Shelter
Appendix 7.3	REA Dive Survey Results
Appendix 7.4	Representative Photographs of Habitats and Species Recorded during Dive Surveys
Appendix 7.5	Benthos Survey Results (Abundance and Biomass) for Both Dry and Wet Season
Appendix 7.6	Raw Data Recorded for Intertidal Surveys within the Assessment Area during Wet Season
Appendix 7.7	Raw Data Recorded for Intertidal Surveys within the Assessment Area during Dry Season

7 Ecological Impact

7.1 Introduction

7.1.1 This section presents an assessment of potential ecological impacts arising from construction and operation of the Project, which has been conducted in accordance with the criteria and guidelines as stated in Annexes 8 and 16 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM) as well as the requirements given in Clause 3.4.7 and Appendix F of the Environmental Impact Assessment (EIA) Study Brief (No. ESB-357/2022). Potential direct, indirect, on-site, off-site, cumulative and residual impacts on ecological resources during construction and operation phases of the Project were identified and evaluated. Mitigation measures have been recommended, where necessary, and residual impacts were assessed.

7.1.2 The assessment has taken into consideration the latest project layout, including the proposed breakwaters alignments with marine access in the form of landing facilities, the proposed land access and the proposed wave wall in the form of floating breakwater, as discussed in Section 2 and as shown in Figure 2.1.

7.2 Environmental Legislation, Standards and Guidelines

7.2.1 This assessment makes reference to the following Hong Kong Special Administrative Region (HKSAR) Government ordinances, regulations, standards, guidelines, and documents that are relevant to ecological impact assessment:

· Environmental Impact Assessment Ordinance (EIAO) (Cap. 499), and its subsidiary legislation – aims to avoid, minimise and control the adverse effects on the environment by designated projects through the application of the environmental impacts assessment process and the environmental permit system.

· EIAO-TM Annex 8 – recommends the criteria to be used for evaluating habitat and ecological impact.

· EIAO-TM Annex 16 – sets out the general approach and methodology for assessment of ecological impacts arising from a project or proposal, to allow a complete and objective identification, prediction and evaluation of the potential ecological impacts.

· EIAO Guidance Note (EIAO-GN) No. 3/2010 Flexibility and Enforceability of Mitigation Measures Proposed in an Environmental Impact Assessment Report – provides guiding principles on the approach to assess the recommended environmental mitigation measures in EIA reports.

· EIAO-GN No. 6/2010 Some Observations on Ecological Assessment from the Environmental Impact Assessment Ordinance Perspective – clarifies the requirements of ecological assessments under the EIAO.

· EIAO-GN No. 7/2010 Ecological Baseline Survey for Ecological Assessment – provides general guidelines for conducting ecological baseline surveys in order to fulfil requirements stipulated in the EIAO-TM.

· EIAO-GN No. 11/2010 Methodologies for Marine Ecological Baseline Surveys – introduces some general methodologies for marine ecological baseline surveys in order to fulfil requirements stipulated in the EIAO-TM.

· Marine Parks Ordinance (Cap. 476) and Subsidiary Legislation – allows for designation, control and management of marine parks and marine reserves through regulation of activities therein to protect, conserve and enhance the marine environment for the purposes of nature conservation, education, scientific research and recreation. The Ordinance came into effect on 1 June 1995.

· Wild Animals Protection Ordinance (Cap. 170) – designated wild animals are protected from being hunted, whilst their nests and eggs are protected from injury destruction and removal. All birds and most mammals, including marine cetaceans, are protected under this Ordinance. The Second Schedule of the Ordinance, which lists all the animals protected, was last revised in June 1997.

· Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586) – gives effect to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in Hong Kong. It restricts import and export of species listed in CITES Appendices so as to protect wildlife from overexploitation or extinction. Certain types of corals are listed in Schedule 1 of the Ordinance, including blue coral (Heliopora coerulea), organ pipe Corals (family Tubiporidae), black corals (order Antipatharia), stony corals (order Scleractinia), firecorals (family Milleporidae) and lace corals (family Stylasteridae). Cetacean including whales, dolphins, porpoises, and rorquals are also listed under Schedules 1 & 2 of the Ordinance. The import, export and possession of scheduled corals, no matter dead or living, is restricted.

· Town Planning Ordinance (Cap. 131) – provides designation of Coastal Protection Areas (CPAs), Sites of Special Scientific Interest (SSSIs), Conservation Area (CA), Country Park, Green Belt (GB) or other specified uses that promote conservation or protection of the environment.

· Chapter 10 of the Hong Kong Planning Standard and Guidelines (HKPSG) – covers planning considerations relevant to conservation. This chapter details the principles of conservation, the conservation of natural landscape and habitats, historic buildings, archaeological sites and other antiquities. It also describes enforcement issue. The appendices list the legislation and administrative controls for conservation, other conservation related measures in Hong Kong and government departments involved in conservation.

· Water Pollution Control Ordinance (Cap. 358) – aims to control water pollution in waters of Hong Kong. Water Control Zones (WCZs) are designated with individual water quality objective to promote the conservation and best use of those waters in the public interest. The most updated water quality objectives for the Victoria Harbour WCZ were revised in June 1997.

7.2.2 This section also makes reference to the following international conventions and national legislation:

· The International Union for Conservation of Nature (IUCN) Red List of Threatened Species – provides taxonomic, conservation status and distribution information on taxa that have been evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those taxa that are facing a higher risk of global extinction.

· The People’s Republic of China National Protection Lists of Important Wild Animals and Plants – lists detailed Class I & II key protected animals and Category I and II plant species under Mainland Chinese Legislation. The list was last updated in February 2021.

7.3 Assessment Methodology

Assessment Area

7.3.1 According to Clause 3.4.7 of the EIA Study Brief No. ESB-357/2022, the assessment area for marine ecology should be the same as the water quality impact assessment area, covering Western Buffer WCZ and Southern WCZ as designated under the Water Pollution Control Ordinance (Cap. 358) (Figure 5.1 refers), and include ecological sensitive receivers in the vicinity of the Project site. As water quality impacts is anticipated to be localised within the Project site, the assessment would focus on the area within and adjacent to the Project boundary (Figure 7.1 refers).

Literature Review

7.3.2 The ecological characteristics of the assessment area were identified through a comprehensive review of the available literature. This review collated ecological information from various reports and publications, as summarised in Table 7.1 below.

Table 7.1 Literature Describing Ecological Resources in the Assessment Area

Relevant Literature	Marine Ecology
Relevant Literature	Coral	Benthos	Intertidal
1) Repositioning and Long Term Operation Plan of Ocean Park (Ocean Park Corporation, 2006)	✓		✓
2) South Island Line (East) (MTR Corporation Limited, 2010)	✓	✓	✓
3) Marine Biodiversity Map (World Wildlife Fund – Hong Kong, 2012)	✓
4) Tai Shue Wan Development at Ocean Park (Ocean Park Corporation, 2014)	✓		✓
5) Aberdeen Boat Club Proposed Development at Middle Island (Aberdeen Boat Club, 2020)		✓

Marine Ecological Survey Methodology

7.3.3 Based on the review of available information on marine ecological resources, relevant survey information is limited and was more than 5 years old. Marine ecological field surveys were therefore conducted to fill the identified information gap, to verify information collected, and to fulfil the requirements of the EIA Study Brief No. ESB-357/2022.

7.3.4 Ecological survey methodologies were prepared according to the requirements stipulated under EIA Study Brief No. ESB-357/2022. Ecological surveys were conducted between September 2022 to February 2023, following the requirements stipulated under Annexes 8 and 16 of EIAO-TM and relevant EIAO-GNs 6/2010, 7/2010 and 11/2010, prior to the implementation of the revised EIAO-GNs in June 2023. All field surveys were carried out in such ways to minimise unnecessary stress or damage to the existing habitats and wildlife. The ecological survey schedule is presented in Table 7.2 and the survey transects / locations are presented in Figure 7.1. Methodologies of the ecological surveys are discussed below. Agreement on the methodologies and schedule was obtained from AFCD prior to commencement of the surveys.

Table 7.2 Marine Ecological Survey Schedule

Marine Ecological Surveys	Wet Season		Dry Season
Marine Ecological Surveys	Sep 2022	Oct 2022⁽¹⁾	Nov 2022	Dec 2022	Jan 2023	Feb 2023
Intertidal Habitats	ü	ü			ü
Soft Substrate Subtidal Habitats	ü				ü
Hard Substrate Subtidal Habitats					ü
Note: (1) Transitional month

Habitat Mapping Survey

7.3.5 Based on the review of relevant aerial photographs and previous literature, marine habitats within the Project site were preliminarily identified, sized, and mapped. A habitat map of suitable scale (1:1000 to 1:5000) showing the types and locations of marine habitats within the assessment area was prepared accordingly. Ground truthing exercise was undertaken in accessible areas to check and verify each identified habitat, with particular attention to Project site. Ecological characteristics of each habitat type, including size, species presence, dominant species found, species diversity and abundance, community structure, ecological value and inter-dependence of the habitats and species, and presence of any features of ecological importance were defined and characterised. Binoculars and aerial photographs were used to observe ecological structure and supplement habitat information where accessibility was limited. Representative photographs of the habitat types and/or any important ecological features identified were taken.

Dive Survey

7.3.6 Spot-check dive surveys (namely C1 to C5) (Figure 7.1 refers) were conducted, with regular zig-zag dive routes covering the areas of Aberdeen Channel. Subtidal substrata (hard substratum seabed and seawall, etc.) at the spot-check dive locations were surveyed for the presence and composition of coral communities, including hard corals (order Scleractinia), octocorals (sub-class Octocorallia) and black corals (order Antipatharia).

7.3.7 As corals were recorded during the spot-check dive survey, a more detailed Rapid Ecological Assessment (REA) (namely REA1 to REA6), was carried out with reference to DeVantier et al. (1998)[1] (see Appendix 7.1 for details). The location of 100 metre (m) REA transect(s) was based on the preliminary results from the spot-check dives. For each transect, the locations (Global Positioning System, GPS) of dive routes, distance surveyed, visibility, the percentage of coral coverage, and the conservation status of coral species in Hong Kong waters were recorded. Representative photographs (e.g. site conditions, substrates, coral species, etc.) were taken. Attention was also paid to the occurrence of marine fishes, in particular pipefish, during the dive surveys for coral.

Benthos Survey

7.3.8 Marine soft bottom benthic fauna was surveyed via grab sampling of seabed sediment at eight sampling sites (namely B1 to B8) (Figure 7.1 refers). At each sampling site, three replicates of grab samples over a 0.1 m² area seabed substrate were collected using a van Veen grab and samples were sieved through 0.5 mm mesh and stained with 1% Rose Bengal solution. For shallow sampling locations (e.g. water depth 2 m or less), sediment samples were collected with a smaller van Veen grab (0.025 m²) with four grab replicates pooled as one usual sediment sample. Collected organisms were counted, weighed and identified to the lowest taxon as far as practicable.

7.3.9 Abundance, biomass, species diversity H’ and evenness J was calculated for pooled data, using the formulae:

H’ = - ∑ ( Ni / N ) ln ( Ni / N ) ; and

J = H’ / ln S

where S is the total number of species in the sample, N is the total number of individuals, and Ni is the number of individuals of the i^th species.

Intertidal Survey

7.3.10 Intertidal communities were surveyed at representative survey locations (namely A1 to A9) (Figure 7.1 refers) by line transect method and walk-through survey method, in order to establish an ecological profile of intertidal habitats within the assessment area.

7.3.11 At each survey location, a qualitative or walk-through survey was conducted to characterise the intertidal flora and fauna present and their occurrence in the survey location. The walk-through surveys help assess whether the sampling exercise in the later quantitative survey had collected representative data (e.g. the number and type of species encountered) and whether the sampling effort was deemed adequate. Effort spent in such qualitative or walk-through survey, such as number of surveyors involved, and the time spent was recorded.

7.3.12 After the walk-through survey, quantitative survey was conducted using line transect method. One line transect was deployed at each survey location. The transects were laid perpendicular to shoreline from high water mark down to low water mark during the low tide period (tide level below 1 m). Along each transect, standard ecological sampling quadrat (dimensions 0.5 m x 0.5 m) was laid at 1 m intervals (or other suitable quadrat dimension and interval distance depending on the field situation). Intertidal epifauna and flora within each quadrat were identified and enumerated. In general, mobile fauna was counted in terms of abundance per unit area. Sessile organisms such as barnacles, oysters and algae were estimated in terms of percentage cover per fixed area. Recorded intertidal fauna were identified to species level as far as possible. Representative photographs of intertidal habitat and flora/ fauna species identified were taken.

7.4 Description of the Environment

Recognised Sites of Conservation Importance

7.4.1 There are no sites of conservation importance located within the assessment area.

Literature Review

7.4.2 Some marine ecological surveys have been conducted in the assessment area under previous studies. The surveyed habitats were primarily dominated by common marine species, as described below.

Marine Habitats

Artificial Seawall

7.4.3 Artificial seawall habitat comprising rip-rap boulders was recorded at the north shore of Tai Shue Wan along Shum Wan Road up to Po Chong Wan. Species assemblages on sloping rubble mound seawalls, which resemble natural coastal conditions, were considered likely to be similar to those on natural rocky shores (Ocean Park Corporation, 2006; Ocean Park Corporation, 2014) ^[2],[3].

Rocky Shore

7.4.4 The coastline along the eastern side of the Aberdeen Channel extending from the south of the bay of Tai Shue Wan to near Sham Shui Kok was recorded as a natural rocky shore habitat. Rocky shore fauna along the coast comprised species typical of semi-exposed rocky shores of Hong Kong waters and followed typical vertical zonation patterns mediated by tidal exposure (Ocean Park Corporation, 2006; Ocean Park Corporation, 2014) ^[2],[3].

Marine Fauna

Coral Communities

7.4.5 Coral survey results from 2007 were reported in Tai Shue Wan Development at Ocean Park (Ocean Park Corporation, 2014)^[3]. In the area of Tai Shue Wan, coral cover, species composition and diversity were recorded as not high, but the communities in all sites were generally in good condition with low level of sedimentation, leaching and mortality (Ocean Park Corporation, 2014)^[3]. The dominant hard coral species included Bernardpora stutchburyi and Montipora peltiformis, which are usually found in deeper community, and only four soft coral species were found in this area. Soft coral cover was 0.6-3% and hard coral cover was 0.6-5%. There are a total of 1-67 hard coral colonies recorded (Ocean Park Corporation, 2006; Ocean Park Corporation, 2014)^[2],[3]. Octocoral communities have also been recorded near Ap Lei Pai (World Wildlife Fund – Hong Kong, 2012)[4].

7.4.6 Other coral sensitive receivers recorded nearby the Project site, within the WCZs but out of the Project site, primarily located along the shore of Brick Hill adjoining Deep Water Bay (about 1 – 1.8 km distant from the Project site). The dominant hard coral species included Leptastrea purpurea and Platygyra acuta, which were recorded in shallow water. Table 7.3 lists out the 28 coral species of conservation importance recorded in previous surveys within the assessment area.

Table 7.3 Coral Species of Conservation Importance Previously Recorded in the Assessment Area (Ocean Park Corporation, 2006; Ocean Park Corporation, 2014)^[2],[3]

Scientific Name	Distribution in Hong Kong ⁽¹⁾	Protection Status	Within Project Site	Western Buffer and Southern WCZ
Hard Coral Species
Acanthastrea sp.	Uncommon	Cap. 586⁽³⁾	ü	ü
Bernardpora stutchburyi	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Coelastrea aspera	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Cyphastrea serailia	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Dipsastraea favus	Abundant	Vulnerable⁽²⁾ Cap. 586⁽³⁾	-	ü
Dipsastraea lizardensis	Common	Endangered⁽²⁾ Cap. 586⁽³⁾	-	ü
Dipsastraea rotumana	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Duncanopsammia peltata	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Favia speciosa	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Favites abdita	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Favites chinensis	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Favites magnistellata	Rare	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Favites pentagona	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Goniastrea favulus	Uncommon	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Hydnophora exesa	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Leptastrea purpurea	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Montipora peltiformis	Common	Endangered⁽²⁾ Cap. 586⁽³⁾	ü	ü
Montipora turgescens	Rare	Endangered⁽²⁾ Cap. 586⁽³⁾	ü	ü
Oulastrea crispata	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Pavona decussata	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Platygyra acuta	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Platygyra carnosa	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Plesiastrea versipora	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Porites lobata	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Psammocora haimeana	Uncommon	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Psammocora profundacella	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	ü	ü
Stylocoeniella guentheri	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	-	ü
Tubastraea sp.	Common	Cap. 586⁽³⁾	ü	ü
Notes: (1) (Chan et al., 2005) (2) (IUCN, 2024). IUCN Red List Version 2024.2 (3) Protected by the Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586)

Benthic Communities

7.4.7 Previous surveys conducted in Aberdeen Channel near Ap Lei Chau Bridge for the South Island Line (East) Project, which is outside of the Project boundary, reported that the benthic communities of Aberdeen Channel near Ap Lei Chau Bridge were of very low abundance and diversity, with no species of conservation importance recorded (MTR Corporation Limited, 2010)[5].

7.4.8 Close to Middle Island, located within the Southern WCZ (about 2 km distant from the Project site), there was record of the Amphioxus species Branchiostoma belcheri under the ecological surveys for Aberdeen Boat Club’s proposed development at Middle Island (Aberdeen Boat Club, 2020)[6]. B. belcheri is classified as “endangered” on the China Species Red List and it is listed mainly to protect it from overfishing, pollution and habitat loss. No record of Amphioxus species was identified within the Project site and Western Buffer WCZ from literature review.

Intertidal Communities

7.4.9 The north-eastern shore of Aberdeen Channel comprises artificial seawall, whereas natural rocky shore habitat is located along the south-eastern side of the Aberdeen Channel (Ocean Park Corporation, 2014)^[3]. In the Tai Shue Wan artificial seawall area, the seawall consists of large boulders. The dominant intertidal species of artificial shore included periwinkles Echinolittorina vidua, barnacles Chthamalus malayensis, Capitulum mitella, Tetraclita japonica and Amphibalanus amphitrite, limpets Patelloida pygmaea, P. saccharina, and Cellana toreuma, rock oysters Saccostrea cucullata, worm-snails Thylacodes adamsii, false limpets Siphonaria laciniosa, and sea slaters Ligia exotica. Algal cover on the sea wall included erect coralline algae Corallina pilulifera, red encrusting algae Hildenbrandia rubra and green encrusting algae Pseudulvella applanata (Ocean Park Corporation, 2014)^[3].

7.4.10 The natural rocky shore at the southeastern side of Tai Shue Wan, extending along towards Sham Shui Kok was dominated by periwinkles Echinolittorina spp., and sea slaters, Ligia exotica were recorded along the coast. At the mid-shore, assemblages were dominated by the limpet Lottia dorsuosa, and barnacles Tetraclita japonica and mussels Mytilisepta virgata. On the low shore, whelks Reishia clavigera and mussels Perna viridis dominated. Algal cover on the rocky shore comprised erect coralline algae Corallina pilulifera, red encrusting algae Hildenbrandtia rubra and red turf algae Gelidium pusillum. No species of conservation importance were recorded within the assessment area.

7.5 Survey Findings

Marine Habitats

7.5.1 Four habitat types were identified within the Project site during recent surveys, comprising artificial seawall, sandy shore, rocky shore and subtidal habitats. Habitat map and representative photographs of the habitats recorded within the assessment area are shown in Figure 7.2 and Appendix 7.2, respectively. The size of these habitats is shown in Table 7.4.

Table 7.4 Habitats Recorded within the Project Site

Habitat Type	Total Area (ha)	% of Project Site
	Within Project Site
Subtidal Habitats	43.64	95.62%
Rocky Shore	0.60	3.25%
Artificial Seawall	1.16	1.08%
Sandy Shore	0.06	0.05%
Total	45.46	100%

Artificial Seawall

7.5.2 The habitat of artificial seawall within the Project site comprises vertical seawalls along both shores of the Aberdeen South Typhoon Shelter and the north shore of Tai Shue Wan, as well as the existing breakwaters made up with large rock amour and its artificial habitat. This artificial habitat supported low species abundance and diversity.

Sandy Shore

7.5.3 A small patch of natural sandy shore habitat approximately 40 m in length was recorded in the Project site, formed by the tombolo between Ap Lei Chau and Ap Lei Pai, at the western side of the Aberdeen Channel.

Rocky Shore

7.5.4 Rocky shore habitat was located along the eastern, the southwestern and the western side of the coastline of the Aberdeen Channel, which was a natural habitat. This exposed shore habitat was comprised of bedrock and large boulders.

Subtidal Habitats

7.5.5 Area within the Project site mainly comprised of soft bottom sediment of the Aberdeen Channel, while subtidal hard bottom located along the coastline with some dumped materials within the channel, taking up approximately 65% and 35% of the subtidal habitats respectively. Habitats of subtidal soft and hard bottom supported a low species diversity and abundance.

Marine Fauna

Coral Communities

7.5.6 Spot-check dives were carried out at five sites (Figure 7.1 refers) with corals recorded at four sites (no coral was recorded at Site C5). The water depth along the dive routes ranged from 4.5 m to 11.5 m. Details of coral records from spot-check dives are presented in Table 7.5.

Table 7.5 Coral Species Recorded at the Spot-check Dive Sites

Site	Maximum Depth (m)	Coral Species	Distribution in Hong Kong⁽¹⁾
C1	8.5	Bernardpora stutchburyi	Common
		Oulastrea crispata	Common
		Tubastraea sp.	Common
C2	7.4	Bernardpora stutchburyi	Common
C2	7.4	Oulastrea crispata	Common
C3	5.2	Bernardpora stutchburyi	Common
		Coelastrea aspera	Common
		Coscinaraea sp.	Common
		Cyphastrea serailia	Dominant
		Dipsastraea favus	Abundant
		Dipsastraea veroni	Common
		Favites abdita	Dominant
		Favites chinensis	Dominant
		Favites pentagona	Dominant
		Hydnophora exesa	Abundant
		Montipora peltiformis	Common
		Oulastrea crispata	Common
		Pavona decussata	Abundant
		Plesiastrea versipora	Abundant
		Psammocora profundacella	Abundant
C4	4.5	Bernardpora stutchburyi	Common
		Oulastrea crispata	Common
		Tubastraea sp.	Common
		Balanophyllia sp.	Common
		Dendronephthya sp.	Common
		Astrogorgia sp.	Common
		Echinomuricea sp.	Common
		Echinogorgia sp.	Common
		Antipathes curvata	Common
C5	11.5	-
Note: (1) (Chan et al., 2005)

7.5.7 Six 100 m REA transects (REA1 – REA6) were also deployed, which corresponded to spot-check dive routes with corals recorded. The GPS coordinate, maximum depth, bottom substrate and underwater visibility of the REA transect are summarised in Table 7.6.

Table 7.6 Details of the REA Transect

Transect	Location (GPS)	Max. Depth (m)	Bottom Substrate	Visibility (m)
REA 1 (C1)	Start:22°14'09.5"N 114°09'39.8"E End: 22°14'09.6"N 114°09'44.3"E	4	Artificial Seawall	1
REA 2 (C2)	Start: 22°14'16.6"N 114°09'51.3"E End: 22°14'16.0"N 114°09'47.8"E	4.5	Artificial Seawall	1
REA 3 (C3)	Start: 22°14'08.0"N 114°09'37.7"E End: 22°14'05.8"N 114°09'36.7"E	3.5	Boulder/Rock	0.5
REA 4 (C3)	Start: 22°14'00.4"N 114°09'37.6"E End: 22°13'58.7"N 114°09'40.4"E	3	Boulder/Rock	0.5
REA 5 (C3)	Start: 22°13'55.9"N 114°09'43.1"E End: 22°13'52.6"N 114°09'43.8"E	4.5	Boulder/Rock	0.5
REA 6 (C4)	Start: 22°13'56"N 114°10'00"E End: 22°13'54.3"N 114°10'02.4''E	4	Boulder/Rock	0.5

7.5.8 Results from the REA dive transects were similar to the spot-check dive survey, with low coverage of coral species recorded, dominated by stress-tolerant hard coral species Oulastrea crispata and Bernardpora stutchburyi. Detailed survey results of the REA dive transects are presented in Appendix 7.3 and representative photos of species of conservation of importance are presented in Appendix 7.4.

7.5.9 Most corals recorded were common species, occurring in low abundance and sparsely distributed. A total of 22 species of coral were recorded but in low coverage (<5%). C1 and C2 which are located on artificial seawall have low number of coral species (3 and 2 respectively) with <1% coral coverage. C3 and C4 represent the natural subtidal habitat which have more coral species compared to artificial seawall. C3 has the highest number of coral species (15 species), all of which are hard coral species dominated by Oulastrea crispata and Bernardpora stutchburyi with <5% coral coverage. Nine coral species were recorded at C4 including hard coral species dominated by Oulastrea crispata and Bernardpora stutchburyi, soft coral Dendronephthya sp., gorgonian species such as Echinomuricea sp. and black coral Antipathes curvata with <5% coral coverage. No seahorse or pipefish were recorded during dive surveys.

Benthic Communities

7.5.10 Benthic grab sampling surveys were conducted at sites B1 to B8 (refer to Figure 7.1). A total of 219 and 304 specimens were collected from benthic grab sampling surveys during dry season and wet season respectively (refer to Table 7.7). A total of 30 genera were identified, with Annelida recorded as the most abundant and diverse phylum. The list of collected specimens during both dry and wet seasons of the benthic community are presented in Appendix 7.5. No species of conservation importance including amphioxus species were recorded.

7.5.11 The benthic communities in the assessment area were dominated by Glycera sp. and bivalve juvenile (Family Veneridae) in dry and wet season respectively. The species diversity was generally lower in dry season than wet season, while species evenness was similar in both seasons (refer to Table 7.8).

Table 7.7 Total Abundance and Biomass of Each Fauna Group of Benthic Communities

Fauna Group	No. of individuals	Percentage (%)	Biomass (g)	Percentage (%)
Dry Season
Annelida	148	67.58	7.583	74.68
Arthropoda	12	5.48	0.038	0.37
Echinodermata	13	5.94	0.023	0.58
Mollusca	40	18.26	0.504	4.96
Chordata	2	0.91	1.999	19.69
Nemertea	4	1.83	0.007	0.07
Total	219	100	10.154	100
Wet Season
Annelida	187	61.51	7.461	60.50
Arthropoda	22	7.24	0.149	1.21
Echinodermata	22	7.24	0.042	0.34
Bryozoa	2	0.66	0.036	0.29
Mollusca	63	20.72	0.825	6.69
Chordata	4	1.32	3.809	30.89
Nemertea	4	1.32	0.010	0.08
Total	304	100	12.332	100

Table 7.8 Total Abundance and Biomass of Benthic Communities Recorded from Each Sampling Site

Sampling Site	No. of individuals	Biomass (g)	Species Evenness (J)	Species Diversity (H’)
Dry Season
B1	18	0.474	0.95	1.99
B2	16	0.223	0.95	1.70
B3	44	3.963	0.93	2.46
B4	19	3.013	0.99	1.77
B5	34	0.127	0.97	2.33
B6	32	0.147	0.90	2.25
B7	29	0.133	0.93	2.38
B8	27	2.074	0.95	2.36
Total	219	10.154	-	-
Wet Season
B1	19	0.5632	0.98	2.26
B2	24	0.3250	0.94	1.83
B3	66	2.0240	0.94	2.78
B4	21	2.665	0.93	2.13
B5	33	0.808	0.94	2.53
B6	46	1.939	0.96	2.65
B7	48	1.573	0.93	2.84
B8	47	2.435	0.95	2.80
Total	304	12.332	-	-

Intertidal Communities

7.5.12 The sampled A1 and A2 intertidal habitats were artificial sloping rip-rap seawall. A3-A6 and A8-A9 are natural rocky shores, and A7 was a sandy shore. A total of 36 and 33 intertidal species were recorded from dry and wet seasons respectively (refer to Appendix 7.6 and Appendix 7.7). Abundance of organism were generally higher at sampling point A4 and A5 during both dry and wet seasons. Species recorded including marine snails (periwinkles, whelks, topshells), barnacles, limpets, bivalves, sea slater, erect and encrusting algae etc. No species of conservation importance were recorded. The overall species richness was generally low at all sampling locations.

7.6 Ecological Value

7.6.1 The ecological importance of recorded habitats was evaluated in accordance with the EIAO-TM Annex 8 criteria and presented in Table 7.9 to Table 7.13 below. Species of conservation importance identified from recent survey are summarised in Table 7.14 and representative photographs are presented in Appendix 7.4.

Artificial Seawall (Intertidal)

7.6.2 This habitat is manmade and has low species abundance and diversity. It is already affected by the heavy marine traffic both within and adjacent to the typhoon shelter area. As a result of its highly artificial nature and the low diversity and abundance of wildlife, the ecological value of the habitat is considered as Very Low. (Table 7.9 refers). No intertidal species of conservation importance were recorded.

Table 7.9 Ecological Evaluation of Artificial Seawall within the Assessment Area

Criteria	Artificial Seawall
Naturalness	Artificial habitat
Size	Medium
Diversity	Low
Rarity	Common habitat in Hong Kong
Re-creatability	Easily re-creatable
Fragmentation	Not fragmented
Ecological linkage	Ecologically linked with other marine habitats
Potential value	Low
Nursery/ breeding ground	No record of nursery or breeding ground
Age	N/A
Abundance/ Richness of wildlife	Low
Ecological value	Very Low

Sandy Shore

7.6.3 Sandy shore within the Project site is a nature habitat but supported very low species abundance and diversity with no intertidal species of conservation importance recorded. Given its small size with very low diversity and abundance of wildlife, and already affected by the heavy marine traffic both within and adjacent to the typhoon shelter area, the ecological value of this habitat is therefore considered as Very Low (Table 7.10 refers).

Table 7.10 Ecological Evaluation of Sandy Shore within the Assessment Area

Criteria	Sandy Shore
Naturalness	High – Natural habitat
Size	Small
Diversity	Very low fauna diversity
Rarity	§ A common habitat in Hong Kong § No records of species of conservation importance in recent survey
Re-creatability	Not re-creatable
Fragmentation	Not fragmented
Ecological linkage	Ecologically linked with adjacent marine habitats
Potential value	Low
Nursery/ breeding ground	No record of nursery or breeding ground
Age	N.A.
Abundance/ Richness of wildlife	Very Low
Ecological value	Very Low

Rocky Shore

7.6.4 Rocky shore within the Project site is a natural habitat with low to moderate species diversity and low abundance recorded. Despite of a low to moderate species diversity, no intertidal species of conservation importance were recorded, thus this habitat is considered to be of Low ecological value (Table 7.11 refers).

Table 7.11 Ecological Evaluation of Rocky Shore within the Assessment Area

Criteria	Rocky Shore
Naturalness	High – Natural habitat
Size	Medium
Diversity	Low to Moderate
Rarity	§ A common habitat in Hong Kong § No records of species of conservation importance in recent survey
Re-creatability	Not re-creatable
Fragmentation	Not fragmented
Ecological linkage	Ecologically linked with other marine habitats
Potential value	Low
Nursery/ breeding ground	No record of nursery or breeding ground
Age	N/A
Abundance/ Richness of wildlife	Low
Ecological value	Low

Subtidal Soft Bottom Habitat

7.6.5 Low diversity and very low abundance of benthic communities were recorded within this habitat. It is already affected by the heavy marine traffic both within and adjacent to the typhoon shelter area. Additionally, no rare species or species of conservation importance were recorded. Thus, the soft bottom habitat is considered to be of Very Low ecological value (Table 7.12 refers).

Table 7.12 Ecological Evaluation of Subtidal Soft Bottom within the Assessment Area

Criteria	Subtidal Soft Bottom
Naturalness	High – Natural habitat
Size	Medium
Diversity	Low fauna diversity of benthic organisms
Rarity	n A common habitat in Hong Kong n No records of species of conservation importance in recent survey
Re-creatability	Not re-creatable
Fragmentation	Not fragmented
Ecological linkage	Ecologically linked with subtidal hard bottom habitats
Potential value	Low
Nursery/ breeding ground	No record of nursery or breeding ground
Age	N.A.
Abundance/ Richness of wildlife	Very Low abundance and biomass
Ecological value	Very Low

Subtidal Hard Substrate Habitat

7.6.6 Coral communities in the Project site were dominated by a low to moderate diversity of common and widespread species, with low abundance and sparse distribution. Despite coral species of conservation importance were recorded, all species are common and widespread in the Hong Kong waters with low coverage (<5%) and sparsely distributed, thus the overall ecological value of the subtidal hard substrate habitat is considered to be of Low ecological value (Table 7.13 refers).

Table 7.13 Ecological Evaluation of Subtidal Hard Bottom within the Assessment Area

Criteria	Subtidal Hard Bottom
Naturalness	Moderate to High (with some artificial boulders)
Size	Medium
Diversity	Low to Moderate
Rarity	n Common habitats in the Hong Kong waters n In current survey, 17 hard coral species such as Bernardpora stutchburyi and Oulastrea crispata, and one black coral species Antipathes curvata were recorded which are considered of conservation importance as all hard and black corals are protected under Cap. 586. n In previous surveys, 21 hard corals species such as Platygyra acuta and Montipora peltiformis, which are protected under Cap. 586, were recorded.
Re-creatability	Low re-creatablility; Corals may recolonise subtidal hard substrata
Fragmentation	Not fragmented
Ecological linkage	Ecologically linked with other marine habitats
Potential value	Low
Nursery/ breeding ground	No record of nursery or breeding ground.
Age	N/A
Abundance/ Richness of wildlife	Low
Ecological value	Low

7.6.7 A total of 32 coral species of conservation importance were recorded within the assessment area from previous and recent surveys (Table 7.14 refers). Among the species recorded, four species were newly recorded during recent survey while 14 species were only recorded during previous studies. This is due to the limited literatures describing ecological resources in the assessment area, and previous surveys for coral communities were conducted from 10 to nearly 20 years ago. Coverage of the previous surveys also cover a boarder area which mostly fall outside of the Project site, where most of the coral species of conservation importance were recorded (Ocean Park Corporation, 2006; Ocean Park Corporation, 2014)2^,3.

Table 7.14 Species of Conservation Importance Recorded within the Assessment Area during Recent Surveys and Previous Studies

Common Name (Scientific Name)	Distribution in Hong Kong⁽¹⁾	Protection Status	Habitat Recorded
Common Name (Scientific Name)	Distribution in Hong Kong⁽¹⁾	Protection Status	Previous Studies⁽⁴⁾	Recent Survey
Coral Communities
Acanthastrea sp.	Uncommon	Cap. 586⁽³⁾	SHB	-
Antipathes curvata	Common	Cap.586⁽³⁾	-	SHB
Balanophyllia sp.	Common	Cap.586⁽³⁾	-	SHB
Bernardpora stutchburyi	Common	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Coelastrea aspera	Common	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Coscinaraea sp.	Common	Cap.586⁽³⁾	-	SHB
Cyphastrea serailia	Dominant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Dipsastraea favus	Abundant	Vulnerable⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Dipsastraea lizardensis	Common	Endangered⁽²⁾ Cap.586⁽³⁾	SHB	-
Dipsastraea rotumana	Abundant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	-
Dipsastraea veroni	Common	Least Concern⁽²⁾ Cap.586⁽³⁾	-	SHB
Duncanopsammia peltata	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Favia speciosa	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Favites abdita	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	SHB
Favites chinensis	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	SHB
Favites magnistellata	Rare	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Favites pentagona	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	SHB
Goniastrea favulus	Uncommon	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	-
Hydnophora exesa	Abundant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Leptastrea purpurea	Abundant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Montipora peltiformis	Common	Endangered⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Montipora turgescens	Rare	Endangered⁽²⁾ Cap. 586⁽³⁾	SHB	-
Oulastrea crispata	Common	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Pavona decussata	Abundant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Platygyra acuta	Dominant	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Platygyra carnosa	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Plesiastrea versipora	Abundant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Porites lobata	Common	Least Concern⁽²⁾ Cap. 586⁽³⁾	SHB	-
Psammocora haimeana	Uncommon	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	-
Psammocora profundacella	Abundant	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	SHB
Stylocoeniella guentheri	Common	Least Concern⁽²⁾ Cap.586⁽³⁾	SHB	-
Tubastraea sp.	Common	Cap.586⁽³⁾	SHB	SHB
Notes: (1) (Chan et al., 2005) (2) (IUCN, 2024) IUCN Red List Version 2024.2 (3) Protected by the Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586) (4) Ocean Park Corporation, 2006; Ocean Park Corporation, 2014 * No species of conservation importance were recorded for benthic and intertidal communities. Habitat Type: SHB: Subtidal Hard Bottom,

7.7 Identification and Evaluation of Environmental Impacts

Construction Phase Ecological Impacts

7.7.1 As discussed in Section 2, the major works items for the Project includes the following:

(i) Proposed eastern breakwater, approximately 340 m in length, pointing to southwest with about 50 m tip bending southward, with open space and proposed marine access in form of public landing facilities (i.e. landing steps / ramp) and associated seabed stabilisation works;

(ii) Proposed western breakwater, approximately 300 m in length, pointing to northeast with about 85 m tip bending northward, with landing facilities for maintenance purpose and associated seabed stabilisation works;

(iii) Proposed land access, approximately 240 m in length, connecting the proposed eastern breakwater to Tai Shue Wan waterfront along the rocky shoreline within the Project boundary;

(iv) Proposed wave wall in the form of floating breakwater of about 110 m in length in the sea area within the ATS expansion area at a location approximately 70 m eastward of the tombolo between Yuk Kwai Shan and Ap Lei Pai;

(v) Modification of the crest of existing eastern breakwater to form a new open space with pedestrian access to Shum Wan Road; and

(vi) Modification of the existing western breakwater, which includes shortening of the breakwater by approximately 70 m with a view to straightening the navigation channel.

7.7.2 The potential impacts arise from the construction and operation phases of the proposed development can be divided into the following categories:

· Direct Impacts

- Loss of habitats; and

- Direct injury / mortality of wildlife.

· Indirect Impacts

- Indirect construction disturbance impacts (e.g. potential deterioration of marine water quality and increased human activities) on marine habitats and wildlife; and

- Indirect disturbance from operation of the proposed breakwaters and associated facilities on marine habitats and wildlife.

Construction Phase Impact Identification

Direct Impacts

Marine Habitat Loss

7.7.3 A summary of permanent and temporary marine habitat loss resulted from the Project’s work items is presented in Table 7.15.

Table 7.15 Summary of Habitat Loss

Proposed works	Habitat Loss
Proposed works	Subtidal Soft Bottom (Sediment) (ha)	Subtidal Hard Bottom (ha)	Intertidal Rocky Shoreline (m)	Artificial Seawall (m)
Construction of proposed breakwaters	n Permanent loss: about 5.1 n Temporary loss due to dredging: about 2.0	n Permanent loss: about 1	n Permanent loss: about 120	-
Construction of proposed land access connecting proposed eastern breakwater	n Permanent loss: about 0.1	n Permanent loss: about 0.3	-	-
Construction of proposed wave wall in the form of floating breakwater	n Permanent loss: no more than 0.1	n Permanent loss: no more than 0.1	-	-
Modification of the existing breakwaters	-	-	-	n Permanent loss: no more than 200

7.7.4 The construction of proposed breakwaters would result in permanent loss of subtidal soft bottom, subtidal hard bottom and intertidal rocky shore habitat of about 5.1 hectares (ha), 1 ha and 120 m respectively. There would also be about 2 ha of temporary subtidal soft bottom habitat loss due to the dredging of seabed. These directly impacted habitats support a low abundance and diversity of intertidal / benthic fauna with coral species of conservation importance recorded.

7.7.5 Seabed composition within the direct impact footprint of the proposed breakwaters was found to mainly made up of soft substrates at the Aberdeen Channel, with bedrock / boulders along the shore. The benthic assemblages comprised of common and widespread species in Hong Kong, dominated by annelid worms with no species of conservation importance recorded. The subtidal hard substrata habitat within the Project site supported sparse and patchy cover (<5%) of locally common coral species which are commonly found in Hong Kong waters. No coral species were recorded along in the middle of the Aberdeen Channel (C5).

7.7.6 A total of 13 coral species of conservation importance would be directly affected by the construction of proposed breakwaters. These included ten hard coral species, such as stress-tolerant Oulastrea crispata and Bernardpora stutchburyi, along the proposed western breakwater (REA5), four hard coral species, such as Tubastraea sp. and Balanophyllia sp. and one black coral species Antipathes curvata along the proposed eastern breakwater (REA6) (Table 7.20 and Appendix 7.3 refer). Given the low ecological value of the habitat (Table 7.13 refers), and that only common and widespread coral species of low coverage (<5%) would be directly affected, the impact on subtidal substrate habitat loss due to construction of proposed breakwaters is considered minor.

7.7.7 Proposed land access will be constructed for public access connecting proposed eastern breakwater. The access will be in form of elevated footpath with placement of Vessel Impact Protection System (VIPS) along the seaward side for protection from wave and vessel induced damage. The elevated footpath and VIPS will be constructed on underwater levelling stones and would not encroach onto the intertidal rocky shore, resulting in permanent loss of about 0.1 ha and 0.3 ha of subtidal soft and hard bottom substrate respectively. Given the small areas of comparatively low ecological value of subtidal habitats affected and that only low coverage (<5%) of the common and widespread stress-tolerant hard coral, Oulastrea crispata, was recorded at the footprint, the ecological impacts of habitat loss due to construction of proposed land access is considered minor.

7.7.8 The proposed wave wall in the sea area within the ATS expansion area would be in form of a floating breakwater anchoring to concrete sinkers on the seabed. The proposed wave wall in the form of floating breakwater is designed to be a prefabricated unit which only involves simple on-site installation with anchoring by chains to the concrete sinkers. The floating footprint of the proposed wave wall and the concrete sinkers would result in an overall permanent loss of approximately 0.1 ha on both subtidal soft and hard bottom habitats respectively, with no coral species recorded within the direct footprint. Given the very small size of habitats affected, no species of conservation importance recorded and only common species with low abundance and diversity would be impacted, the ecological impacts of habitat loss due to construction of wave wall in the form of floating breakwater is considered to be minor.

7.7.9 About 200 m artificial seawall of the existing western breakwater would be lost permanently due to breakwater shortening and modification works. As evaluated in Table 7.9, artificial seawall within the assessment area has very low ecological value with low species diversity. The intertidal species recorded were mostly common in Hong Kong and no species of conservation importance recorded. Given that the modification is anticipated to be small scale works on artificial habitat, and that only common intertidal species were recorded, the ecological impact of artificial seawall habitat loss from such modification is considered to be minor.

Impacts to Species of Conservation Importance

7.7.10 As discussed in Section 2, the impact on natural habitats has been minimised through careful design of the major works items (i.e. proposed wave wall in the form of floating breakwater and breakwaters). A total of 13 of coral species of conservation importance were recorded within the direct footprint. All these species (12 hard coral and one black coral species as shown in Table 7.20) are commonly recorded and widespread in the Hong Kong waters, which were all recorded within the footprint of the proposed breakwaters and only one stress-tolerant hard coral, Oulastrea crispata, recorded within the proposed land access footprint.

7.7.11 Considering the overall small area of habitat affected with low coverage (<5%) and sparse distribution of coral species recorded, the overall significance of direct impacts to coral species of conservation importance is anticipated to be minor. No mitigation measures would be required for the loss of common corals. Furthermore, eco-shoreline features incorporated in the future breakwater could further enhance the biodiversity of the habitat.

Direct Injury / Mortality on Wildlife

7.7.12 Construction activities may cause direct injury / mortality to wildlife. Species with higher mobility were not anticipated to be significantly impacted, but fauna with lower mobility would be subjected to higher risk of injury or mortality. Given that the Project site would be mainly at the middle of the Aberdeen Channel, which is subjected to existing high level of disturbance from the typhoon shelter and less preferable to be utilised by wildlife, and that the proposed works would be confined within the works area to avoid unnecessary encroachment into natural habitats, the impact is considered as minor.

Indirect Impacts

Disturbance Impacts on Marine Habitats and Wildlife from Deterioration of Marine Water Quality

Elevation of Suspended Solids

7.7.13 The dredging of the seabed and the installation of a breakwater may elevate sediment levels in construction site runoff, which could result in an increase in suspended solids (SS) and subsequently lead to higher turbidity. Increased SS could negatively impact benthic organisms and coral species, especially hermatypic hard corals that rely on photosynthetic algae, as the amount of light reaching the water column decreases, it might lead to growth arrest and bleaching in hard corals, depending on duration (DeSalvo et al., 2012)[7]. Soft and gorgonian corals are less prone to sedimentation impacts as they feed independently without contributions from algal associates. Therefore, they are less sensitive to light reduction due to increased turbidity. Increased SS could also potentially affect other marine wildlife or clog their respiratory and feeding systems and may lead to lethal effects.

7.7.14 According to Section 5, the unmitigated sediment plume (without silt curtain) is retained within the Project site, whereas the SS predictions at coral communities identified within the Project site (i.e. at Tai Shue Wan and south of Tai Shue Wan) are not in compliance with relevant criteria (100 g/m²/day). Double silt curtain has been proposed as mitigation measure in relation to SS elevation (Section 5 refers). The mitigated SS plume due to the proposed dredging and installation of breakwater would then be highly localised and restricted within the Project site and thus only minimal SS elevations at water sensitive receivers (WSRs) within the assessment area (C8 & C9 – identified corals communities) (<55.8 g/m²/day) is anticipated under mitigated scenario.

7.7.15 As detailed in Section 5, release of SS under dredging works of the Project will be further minimised by the use of closed grab dredger and the dispersion of pollutants will be confined within the dredging site by double silt curtains. Given the SS elevations would be localised, temporary and minimal, the indirect impacts on marine habitats and wildlife arising from the elevation of SS is considered minor.

Dissolved Oxygen Depletion

7.7.16 The increase of SS might also lower the oxygen level which could affect stationary species, whilst mobile species would tend to temporarily avoid impacted areas, resulting a temporary reduction in aquatic life abundance. Elevated SS reduces light penetration, lowers the photosynthetic rate of phytoplankton and thus lowers the rate of oxygen production in the water column. In addition, the release of inorganic substances from sediments may cause eutrophication and algal bloom, where oxidation of dead algae may in turn use up some of the oxygen in the water. Should oxygen levels be depleted to low levels, fish, especially those in early life stages may be unable to tolerate such conditions and suffer hypoxia-induced mortality and/or stress including reduced feeding and growth rate.

7.7.17 The Water Quality Objective (WQO) standard for the Western Buffer WCZ and Southern WCZ regarding dissolved oxygen (DO) levels for depth-averaged and bottom-waters should remain above 4.0 mg/L and 2.0 mg/L respectively. Based on assessment in Section 5, the depletion in DO level caused by the proposed works, even without any mitigation measures in place under worst case scenario, is anticipated to be minimal (<0.12 mg/L). The DO concentrations at all ecological sensitive receivers (coral communities identified) would comply with and are expected to be higher than the WQO of 4.0 mg/L for the depth-averaged DO WQO. Thus, indirect impacts on marine habitats and wildlife arising from the oxygen depletion is considered insignificant.

Release of Contaminants from Marine Works

7.7.18 Moreover, dredging operations and Deep Cement Mixing (DCM) have the potential to release contaminants from marine sediments, which could elevate the concentration of harmful substances and cause lethal or sub-lethal effects on marine fauna, depending on species tolerance, contaminant levels and water flow rate, etc. Certain contaminants have the ability to accumulate in the tissues of fauna, particularly in fish, which can lead to sub-lethal effects such as changes in behaviour, reproductive failure, and increased susceptibility to diseases. However, the large volume of marine water is expected to quickly dilute any contaminants that may be released during dredging. Also, the impact of dredging is considered to be acceptable as the works would be temporary, localised and relatively small in scale, thus indirect impacts on marine habitats and wildlife is considered as insignificant.

Water Quality Deterioration due to Construction Workforce and Marine Vessels

7.7.19 There are possibilities that accidental spills of oils, other chemicals and contaminated water would be occurred from construction site which could affect coral and marine benthic communities, resulting in lethal / sublethal impacts on marine wildlife. Through appropriate treatment of discharged or recharged chemically contaminated water and wastewater, the impacts due to water quality deterioration to coral and marine benthic communities would be minimised. Given that the diversity and abundance of species recorded was low within the Project site, it is therefore anticipated that with proper implementation of mitigation measures (refer to Section 7.9), the direct impact is anticipated to be minor.

Disturbance Impacts on Marine Wildlife from Underwater Noise and Vibration

7.7.20 The increased in construction vessels and construction works (i.e. DCM, seabed dredging) would generate background underwater noise and vibration, which marine wildlife in vicinity to the Project site are anticipated to be affected, and displaced to utilise alternative habitats within the assessment area due to disturbance. Given that the Project site and adjacent area are already subjected to existing high level of marine traffic from the typhoon shelter, marine wildlife within and in vicinity to the Project site are expected to have adapted to high level of background underwater noise. According to Section 4, use of quieter Powered Mechanical Equipment (PME) and good-site practices would also be implemented during construction phase, it is therefore anticipated that underwater noise disturbance impacts to marine wildlife in the vicinity of Project site is considered minor.

Disturbance Impacts on Corals from Reduction of Sunlight

7.7.21 It is anticipated that construction vessels (i.e. dump lighters) would be stationed within the proposed works area during the construction phase for longer period of time when compared with normal vessel travelling within the Project site. Provided that these construction vessels are larger in size, sunlight would be prevented from reaching seabed beneath the vessels. As discussed in Section 7.7.13, hermatypic hard coral would potentially suffer from growth arrest to bleaching if sunlight was insufficient over long duration. However, these construction vessels are expected to distribute across different works areas and construction phase of the Project would be implemented in stages. Impacts of reduction of sunlight by construction vessels would therefore be temporary and localised in nature. Moreover, most of these construction vessels would be stationed in the middle of the Aberdeen Channel to facilitate construction works, where no coral species were recorded (Site C5). Given that only low coverage of coral species were recorded along near coast of the channel, and that reduction of sunlight on seabed due to the construction vessels would be temporary and minimal, disturbance impacts on corals is anticipated to be minor.

Operation Phase Ecological Impacts

Direct Impacts

Impacts on Marine Habitats and Wildlife

7.7.22 The entire Project site would become part of the expanded area of Aberdeen Typhoon Shelter upon operation of the Project with no additional area of habitat loss. The increased boat mooring and anchoring activities inside the marine area protected by the proposed breakwaters could impact the subtidal soft bottom of the Project site as anchors and chains would need to be deployed on the subtidal soft bottom to hold the boats in position, which could be detrimental to benthic communities. The associate cables and chains could also increase the damaged area of subtidal soft bottom by dragging across the substratum, however, this is atypical to occur under normal circumstances (Giglio et al., 2017)[8]. Given the very low ecological value of the impacted habitat, the impact is anticipated to be insignificant.

Indirect Impacts

Impacts from Potential Changes in Hydrodynamics Properties and Hydrology

7.7.23 The proposed breakwaters might alter the hydrodynamic regime, and modifying the distribution and/or composition of the marine food sources for benthic organisms, which might also alter the interactions of the marine wildlife in the food web (Carugati et al., 2018)[9]. However, due to the low diversity and abundance of the subtidal organisms, the impact would be considered as minor.

Disturbance Impacts from Marine Traffic

7.7.24 More frequent marine traffic would be expected during operation phase in the assessment area (with approximately 326 daily vessel movements entering and leaving the ATS in 2023 to approximately 415 daily vessel movements in 2040 and additional marine traffic of approximately 68 vessels per day generated from the proposed landing facilities at the proposed eastern breakwater starting from 2030). Such increase of marine traffic near the proposed breakwaters would generate disturbances including underwater noise and water pollution. However, as the area is already subjected to the existing marine traffic from the typhoon shelter, and only low abundance of fauna species were recorded in the affected marine habitats, the disturbance impact is expected to be low. The increase of mooring of boats within the proposed breakwaters would also create human disturbance such as waste disposal and boat maintenance works, water pollution by fuel and lubricants from combustion engines and biocides from anti-fouling paint (Sagerman et al., 2020)[10]. Given that the subtidal and intertidal habitats are of very low to low ecological value, the disturbance impact is considered to be minor.

Disturbance Impacts from Reduction of Sunlight

7.7.25 Increase in marine traffic within the expanded area of Aberdeen Typhoon Shelter and proposed land access connecting proposed eastern breakwater could potentially reduce amount of sunlight in the water column during operation phase. The proposed land access would be in form of elevated footpath by installing prefabricated/in-situ land access segments, supported by precast/in-situ columns and pad footings, with potential reduction of sunlight expected from the supporting structure at certain time of the day. Shading effect from increased marine vessels is also expected at minimal level as the vessels are not anticipated to station at the landing facilities for long duration. Given that only low coverage of stress-tolerant and widespread coral species Oulastrea crispata was recorded within the footprint, the area is already subjected to existing disturbance and that the impact would be localised and minimal, disturbance impact on subtidal hard bottom habitat is considered to be insignificant.

Evaluation of Ecological Impact

7.7.26 Potential ecological impacts on the identified habitats within the Project site associated with the construction and operation of the Project have been evaluated in accordance with the Annex 8 of the EIAO-TM, as presented in Table 7.16 to Table 7.19. The evaluation of major ecological impact on the species of conservation importance is presented in Table 7.20, and an overall summary of potential ecological impacts and mitigation measures is summarised in Table 7.21.

Artificial Seawall

7.7.27 The main impact to artificial seawall arising from the Project would be habitat loss due to modification of existing breakwaters. The existing breakwater to be modified is artificial habitat with low intertidal fauna abundance and diversity dominated by common species. Considering its very low ecological value (Table 7.9 refers) and the small area of loss (no more than 200 m at the tip of the existing western breakwater) of artificial habitat, the direct impact of habitat loss is therefore considered Low if unmitigated (Table 7.16 refers).

7.7.28 Temporary construction and operational disturbance impact to artificial seawall within the Project site and remaining assessment area are considered as Low and Negligible respectively. This is because the habitat is of very low ecological value and already subjected to the existing busy marine traffic from the typhoon shelter (Table 7.16 refers).

Table 7.16 Evaluation of Ecological Impact to Artificial Seawall within the Assessment Area

Evaluation Criteria	Artificial Seawall
Habitat quality	Very Low
Species	Project Site and Assessment Area outside of Project Site n Low fauna abundance and diversity n No species of conservation importance recorded from recent surveys or previous studies
Size / Abundance	n Permanent loss: no more than 200 m
Duration	n Direct impact (permanent habitat loss) within footprint of the proposed works would be permanent n Construction phase indirect disturbance impacts would be temporary n Operation phase indirect disturbance impacts would be permanent
Reversibility	n Permanent habitat loss would be irreversible. n Construction phase indirect disturbance impacts would be reversible n Operation phase indirect disturbance impacts would be irreversible
Magnitude	Low (Project Site) Negligible (Area adjacent to Project Site)
Overall impact evaluation	Low (Project Site) Negligible (Area adjacent to Project Site)

Sandy Shore

7.7.29 No direct impact is anticipated for sandy shore habitat within Project site as well as the assessment area. Considering its very low ecological value (Table 7.10 refers) and that it is already subjected to existing busy marine traffic from the typhoon shelter, temporary construction and operational disturbance impact to the habitat within the Project site and remaining assessment area are considered as Low and Negligible respectively (Table 7.17 refers).

Table 7.17 Evaluation of Ecological Impact to Sandy Shore within the Assessment Area

Evaluation Criteria	Sandy Shore
Habitat quality	Very Low
Species	Project Site and Assessment Area outside of Project Site n Low fauna diversity n No flora species of conservation importance recorded
Size / Abundance	n This habitat will not be directly affected
Duration	n Construction phase indirect disturbance impacts would be temporary n Operation phase indirect disturbance impacts would be permanent
Reversibility	n Construction phase indirect disturbance impacts would be reversible n Operation phase indirect disturbance impacts would be irreversible
Magnitude	Low (Project Site) Negligible (Area adjacent to Project Site)
Overall impact evaluation	Low (Project Site) Negligible (Area adjacent to Project Site)

Rocky Shore

7.7.30 The main impact to rocky shore arising from the Project would be habitat loss due to construction of proposed breakwaters. Given that the species found on rocky shore habitat are common and of low abundance with low ecological value (Table 7.11 refers) and only short length of approximately 120 m would be loss, the direct habitat loss impact is therefore considered Low if unmitigated (Table 7.18 refers).

7.7.31 Temporary construction and operational disturbance impact to rocky shore within the Project site and remaining assessment area are considered as Low and Negligible respectively. This is because the habitat is of low ecological value and already subjected to the existing busy marine traffic from the typhoon shelter (Table 7.18 refers).

Table 7.18 Evaluation of Ecological Impact to Rocky Shore within the Assessment Area

Evaluation Criteria	Rocky Shore
Habitat quality	Low
Species	Project Site and Assessment Area outside of Project Site n Low fauna diversity n No flora species of conservation importance recorded
Size / Abundance	n Permanent loss of about 120 m
Duration	n Direct impact (permanent habitat loss) within footprint of the proposed works would be permanent n Construction phase indirect disturbance impacts would be temporary n Operation phase indirect disturbance impacts would be permanent
Reversibility	n Permanent habitat loss would be irreversible n Construction phase indirect disturbance impacts would be reversible n Operation phase indirect disturbance impacts would be irreversible
Magnitude	Low (Project Site) Negligible (Area adjacent to Project Site)
Overall impact evaluation	Low (Project Site) Negligible (Area adjacent to Project Site)

Subtidal Habitats

7.7.32 The main impact to both subtidal hard and soft bottom habitats arising from the Project would be habitat loss due to construction of the proposed breakwaters, proposed land access and proposed wave wall in the form of floating breakwater.

7.7.33 The subtidal soft bottom habitat within the Project site has low diversity and very low abundance of benthic communities with no species of conservation importance recorded. Considering its very low ecological value (Table 7.12 refers) given its limited fauna diversity, and that direct impact of habitat loss is relatively small (approximately 5.3 ha and 2.0 ha for permanent and temporary loss respectively) within the Project site, the direct impact of habitat loss are therefore considered Low if unmitigated (Table 7.19 refers).

7.7.34 Whereas habitat loss of subtidal hard bottom habitat is very small (approximately 1.4 ha) supporting low abundance and sparse distribution of coral species. Considering its low ecological value (Table 7.13 refers) and the very small area of loss, the direct impact of habitat loss is therefore considered Low if unmitigated (Table 7.19 refers).

7.7.35 Temporary construction and operational disturbance to both subtidal soft and hard bottom habitats within Project site and adjacent area are considered as Low (Table 7.19 refers). This is because these habitats are of very low to low ecological value and already subjected to the existing busy marine traffic from the typhoon shelter.

7.7.36 Within the subtidal hard bottom habitat that is subject to loss, 12 hard corals and one black coral species of conservation importance were recorded and potentially be directly impacted. Indirect impact of shading induced by marine vessels and work elements during both construction and operation phases are expected to be temporary, localised and at minimal level within the Project site. Considered that all the species are locally common or abundant species recorded in low coverage, and the directly impacted area is very small for each proposed work elements (Table 7.15 refers), direct impact to these coral species of conservation importance is anticipated to be Low if unmitigated (Table 7.19 refers).

Table 7.19 Evaluation of Ecological Impact to Subtidal Habitats within the Assessment Area

Evaluation Criteria	Subtidal Soft Bottom	Subtidal Hard Bottom
Habitat quality	Very Low	Low
Species	Project Site and Assessment Area outside Project Site n Low fauna diversity of benthic organisms n No species of conservation importance recorded from recent surveys or previous studies	Project Site n Low diversity of subtidal epifauna n 17 hard coral species, one black coral and three gorgonian species recorded in recent survey Assessment Area outside Project Site n Sparse coverage of coral consisting of 32 coral species were recorded in recent surveys and previous studies.
Size/ Abundance	n Permanent loss of about 5.3 ha n Temporary loss of about 2.0 ha	n Permanent loss of about 1.4 ha
Duration	n Direct impact (permanent habitat loss) within footprint of the proposed works would be permanent n Direct impact (temporary habitat loss) within footprint of the proposed dredging extent would be temporary	n Direct impact (permanent habitat loss) within footprint of the proposed works would be permanent
Duration	n Construction phase indirect disturbance impacts (e.g. water quality impacts) would be temporary n Operation phase indirect disturbance impacts (e.g. increased marine traffic) would be permanent
Reversibility	n Permanent habitat loss would be irreversible n Temporary habitat loss would be reversible	n Permanent habitat loss would be irreversible
Reversibility	n Construction phase indirect disturbance impacts would be reversible n Operation phase indirect disturbance impacts would be irreversible
Magnitude	Low (Project Site) Negligible (Area adjacent to Project Site)	Low (Project Site) Negligible (Area adjacent to Project Site)
Overall impact evaluation	Low (Project Site) Negligible (Area adjacent to Project Site)	Low (Project Site) Negligible (Area adjacent to Project Site)

7.7.37 Potential impacts to species of conservation importance recorded within the Project site are described in above sections. A summary and evaluation of potential impacts from construction and operation phases of the Project on all species of conservation importance recorded is presented in Table 7.20.

Table 7.20 Overall Impacts on Marine Species of Conservation Importance within the Project Site

Species of Conservation Importance Recorded	Description of Construction and Operation Phases Impacts	Impact Evaluation
*Coral Communities*
Antipathes curvata Balanophyllia sp. Bernardpora stutchburyi Coelastrea aspera Cyphastrea serailia Dipsastraea favus Dipsastraea veroni Favites abdita Favites chinensis Oulastrea crispata Plesiastrea versipora Psammocora profundacella Tubastraea sp.	Construction phase Direct impact on these species is anticipated to be low due to the low coverage, and all are commonly widespread in Hong Kong waters. Disturbance impact on these species is also expected to be low as the constructions works would be localised.	Low
	Operation phase Insignificant hydrodynamic changes and potential indirect marine water quality impacts would be anticipated from operation of the Project. The coral communities are expected to recolonise the substrata easily.	Low
Coscinaraea sp. Favites pentagona Hydnophora exesa Montipora peltiformis Pavona decussata	Construction phase Although these species were recorded within the Project site, no direct impact is anticipated. Indirect disturbance impact on these species is expected to be low due to its temporary nature and good site practices.	Low
	Operation phase These species are already subjected to existing disturbance from the typhoon shelter. As disturbance impacts from operation of the Project would be insignificant, indirect impact on these species is anticipated to be negligible.	Negligible

7.8 Cumulative Impact

7.8.1 The potential concurrent marine-based projects within the Western Buffer and Southern WCZs were reviewed in Section 2.13 and Table 2.10. According to Section 2.13 and Table 2.10, with reference to the available approved EIA reports, project profiles and EIA study briefs and given the large separation distances between the projects and ATS expansion area, the potential concurrent marine-based projects are not anticipated to result in adverse cumulative impacts. In addition, based on Section 5, no adverse water quality impact due to marine-based construction and operation of the Project is anticipated with the implementation of the recommended mitigation measures and environmental monitoring and audit (EM&A) programme. Given the above, no adverse cumulative ecological impact is anticipated.

7.8.2 The overall summary of potential ecological impacts arising from the construction and operation of the Project as well as mitigation measures requirements are summarised in Table 7.21.

Table 7.21 Summary of Potential Ecological Impacts and Mitigation Measures Requirements during the Construction and Operation Phase

Potential Impact		Source	Receiver	Nature of Impact	Overall Impact Significance	Mitigation Measures Proposed
Construction Phase	Direct Impact
	Marine habitat loss	Construction of proposed breakwaters	Marine habitats (subtidal soft bottom, subtidal hard bottom and intertidal rocky shoreline)	Permanent loss of marine habitats · About 5.1 ha subtidal soft bottom · About 1 ha subtidal hard bottom · About 120 m intertidal rocky shoreline	Low	No marine ecology-specific mitigation measures required
		Construction of proposed breakwaters	Marine habitat (subtidal soft bottom)	Temporary loss of marine habitat · About 2 ha subtidal soft habitat	Low	No marine ecology-specific mitigation measures required
		Construction of proposed land access connecting proposed eastern breakwater	Marine habitats (subtidal soft bottom and subtidal hard bottom)	Permanent loss of marine habitats · About 0.1 ha subtidal soft bottom · About 0.3 ha subtidal hard bottom	Low	No marine ecology-specific mitigation measures required
		Construction of proposed wave wall in the form of floating breakwater	Marine habitats (subtidal soft bottom and subtidal hard bottom)	Permanent loss of marine habitat · < 0.1 ha subtidal soft bottom · < 0.1 ha subtidal hard bottom	Low	No marine ecology-specific mitigation measures required
		Shortening and modification of existing western breakwater	Marine habitats (artificial seawall)	Permanent loss of marine habitat · No more than 200 m of artificial seawall	Low	No marine ecology-specific mitigation measures required
	Direct impact on coral species of conservation importance	Construction of proposed breakwaters and proposed land access connecting proposed eastern breakwater	Coral species of conservation importance	Direct loss of 12 hard coral species and one black coral species which are all common species recorded in low coverage with sparse distribution	Low	No marine ecology-specific mitigation measures required
	Direct injury / mortality to marine wildlife	Construction of proposed breakwaters, proposed land access connecting proposed eastern breakwater, proposed wave wall in the form of floating breakwater and shortening and modification of existing western breakwater	All marine wildlife other than species of conservation importance within Project footprint	Potential injury / mortality of marine wildlife	Low	No marine ecology-specific mitigation measures required
	Indirect Impact
	Deterioration of marine water quality	Dredging of seabed and installation of proposed breakwaters	Marine habitats and wildlife	Potential temporary elevated suspended solid level and deterioration of water quality	Low for SS and contaminants released from construction workforce and marine vessels with mitigation measures in place.	Yes, refer to Section 7.9 (Measures to minimise water quality impacts in accordance with Section 5)
	Deterioration of marine water quality	Dredging of seabed and installation of proposed breakwaters	Marine habitats and wildlife		Insignificant for DO and contaminants released from dredging
	Disturbance impacts on marine wildlife from underwater noise and vibration	Construction vessels and construction works	All marine wildlife	Temporary and localised to the immediate vicinity of the Project site	Low	No marine ecology-specific mitigation measures required
	Disturbance impacts on corals from reduction of sunlight	Construction vessels	Coral species of conservation importance	Potential growth arrest or bleaching from reduction of sunlight based on duration	Low	No marine ecology-specific mitigation measures required
Operation Phase	Direct Impact
	Impacts on marine habitats and wildlife	Work items of the Project (i.e. proposed breakwaters, proposed land access and proposed wave wall in the form of floating breakwater)	Marine habitats and wildlife	Permanent and localised to Project footprint with no additional area loss	Insignificant	No marine ecology-specific mitigation measures required
	Impacts on marine habitats and wildlife	Increased boat mooring and anchoring activities	Marine habitat (subtidal soft bottom)	Permanent and localised to subtidal soft bottom habitat within the proposed breakwaters	Insignificant	No marine ecology-specific mitigation measures required
	Indirect Impact
	Indirect impacts from potential changes in hydrodynamics properties and hydrology	Installation of proposed breakwaters	All marine wildlife	Changes in the distribution and/or composition of the marine food source and food web interactions	Low	No marine ecology-specific mitigation measures required
	Indirect disturbance from marine traffic	Increased operation of marine vessels in the area	Marine habitats and wildlife	Permanent and localised to the vicinity of the marine habitats within the proposed breakwaters	Low	No marine ecology-specific mitigation measures required
	Indirect disturbance impacts from reduction of sunlight	Operation of proposed land access and increased operation of marine vessels	Marine habitat (subtidal soft bottom) and coral species of conservation importance (Oulastrea crispata)	Temporary and localised to areas of proposed land access (i.e. elevated footpath)	Insignificant	No marine ecology-specific mitigation measures required

7.9 Mitigation of Adverse Environmental Impacts

7.9.1 According to Annex 16 of the EIAO-TM and EIAO-GN. 3/2010, ecological impacts on important habitats and the associated wildlife should be mitigated by avoidance, minimisation and compensation approaches to the maximum practical extent.

Avoidance

7.9.2 Various options were considered as described in Section 2 to arrive at the final design option for the Project. The final design option has avoided ecological impact as far as practicable. For instance, elevated footpath design has been adopted for proposed land access to the proposed eastern breakwater to avoid encroachment onto intertidal habitat, which is part of the Coastal Protection Area (CPA) designated for conservation of existing natural landscape and scenic quality of the area. The proposed pier at Tai Shue Wan has been integrated as part of the proposed eastern breakwater in the form of public landing facilities, which reduce direct impact footprint of habitat loss. Also, the wave wall under the current design is proposed to be in form of floating breakwater, which avoided encroachment into the adjacent sandy shore and intertidal rocky shore between Ap Lei Chau and Ap Lei Pai, as well as subtidal soft bottom habitat since no dredging would be conducted.

Minimisation

Minimisation of Water Quality Impact

7.9.3 Mitigation measures to control water quality impact are recommended in the water quality impact assessment (Section 5 refers) to confine sediment plume within the proposed dredging area and to minimise indirect impact to the nearby intertidal and subtidal organisms. The recommended mitigation measures include use of closed grab, restriction of dredging production rate (no more than 45 m³ per hour at caisson area and 30 m³per hour at landfall area) and deployment of silt curtains. With the adoption of the recommended mitigation measures, the impact on marine ecology due to the deterioration in water quality as a result of dredging works would be minimised.

7.9.4 To minimise the contamination of wastewater discharge, accidental chemical spillage, construction site run-off and illegal dumping to the marine waters, the mitigation measures include:

· The good site practices outlined in ProPECC PN 2/24 “Construction Site Drainage” should be strictly followed to minimise surface runoff.

· Installation of double silt curtain and sand blanket around the works area to reduce the dispersion of SS. Closed-grab dredging is also recommended.

· Open stockpiles of construction materials (e.g. aggregates, sand and fill material) on sites should be covered with tarpaulin or similar fabric during rainstorms;

· All disposal of chemical waste should be carried out in compliance with the Waste Disposal Ordinance. Emergency Spillage Plan should be established during the construction phase as precautionary measures so that appropriate actions to prevent or reduce risks to sensitive receivers in the vicinity can be undertaken in the event of an accidental spillage.;

· Chemical toilets should be provided within the construction site and properly maintained. All effluent discharged from the construction site should comply with the standards stipulated in the “Technical Memorandum on Standards for Effluents Discharged into Drainage and Sewerage Systems, Inland and Coastal Waters” (TM-DSS).

· A no-dumping policy should be applied to prohibit dumping of wastes, chemicals, oil, trash, plastic, or any other substance that would potentially be harmful to marine habitats. All personnel working on Project-related activities at construction sites must have training regarding the no-dumping policy.

· Removal of floating refuse should be conducted daily to keep water within the site boundary and neighbouring water free from rubbish during the construction.

Compensation

7.9.5 The loss of intertidal and subtidal habitats, ecological resources and indirect water quality changes from the Project’s construction and operation were expected to have low to insignificant impact, and no unacceptable adverse ecological impact would be resulted. Therefore, no ecological compensation measure is proposed.

Enhancement

7.9.6 The subtidal portion of the proposed and modified breakwaters will provide approximately 4.55 ha of artificial hard substrates for potential colonisation of corals or other epibenthos. Whereas construction of proposed land access connecting proposed eastern breakwater would also create approximately 0.2 ha of artificial subtidal hard bottom habitat. Eco-shoreline features will be incorporated into these breakwaters to enhance the existing intertidal and subtidal habitats by creating a variety of artificial microhabitats that facilitate the colonisation of intertidal and subtidal epifauna.

7.9.7 Approximately 1380 m of artificial intertidal habitat would also be created under the construction of proposed breakwaters as well as the proposed land access connecting proposed eastern breakwater. Apart from the surface of the proposed breakwaters, vertical surface of the VIPS (Section 7.7.7 refers) facing marine water would also incorporate eco-feature to provide artificial habitats that support communities associated with rocky shore. Artificial habitats created by the Project is summarised in Table 7.22.

Table 7.22 Artificial Habitats Created by the Project

Proposed works	Artificial Habitats Created
Proposed works	Artificial Subtidal Hard Bottom (ha)	Artificial Seawall (m)
Construction of proposed breakwaters	About 4.35	About 1080 (vertical face of caisson and blockwork seawall)
Construction of proposed land access connecting proposed eastern breakwater	About 0.2	About 300 (vertical face of VIPS)
Modification of the existing breakwaters	About 0.2	-
Total	About 4.75	About 1380

7.10 Evaluation of Residual Impacts

7.10.1 With the effective implementation of mitigation measures proposed in Section 7.9, there would be no significant residual impacts on marine ecology, and overall impacts are considered acceptable.

7.11 Environmental Monitoring and Audit Requirements

Construction Phase

7.11.1 Regular weekly marine water quality monitoring would be undertaken during the construction phase to ensure that all the recommended mitigation measures are properly implemented as detailed in the Section 5 of Water Quality Impact.

7.11.2 Weekly site audit should be carried out throughout the construction phase to ensure recommended mitigation measures described in Section 7.9 are fully implemented. In case of non-compliance, contractor should be informed to strengthen the proposed mitigation measures accordingly. Details of EM&A requirements are presented in the separate EM&A Manual.

Operation Phase

7.11.3 During operation phase, no specific ecological monitoring is required as residual impacts on the marine ecology are negligible. However, a four-weeks post-construction water quality monitoring programme will be in place upon completion of marine works as mentioned in Section 5.

7.12 Conclusion

7.12.1 Marine habitats within and adjacent to the Project site include subtidal hard substrate and soft bottom habitats, and intertidal habitats (i.e. rocky shore, sandy shore and artificial seawall), which are considered to have very low to low ecological value.

7.12.2 Among the recorded marine habitats, no direct impact is anticipated for sandy shore. The proposed marine-based works would cause permanent loss and temporary loss of subtidal soft substrate habitats (about 5.3 ha and 2.0 ha respectively), permanent loss of subtidal hard substrate habitats (about 1.4 ha), intertidal rocky shore (about 120 m), and artificial seawall (about 200 m). Given the small size and very low to low ecological value of the affected habitats, the direct impact of habitat loss is therefore expected to be Low for all these habitats.

7.12.3 Major disturbance impacts arise from the Project would be resulted from impact from the temporary change in water quality induced by dredging in construction phase, mooring and anchoring activities inside the marine area as well as underwater noise and pollution generated from more frequent marine traffic during the operation phase. Given that subtidal and intertidal habitats are all of very low to low ecological value and that proper water quality mitigation measures would be adopted on site, the indirect disturbance impacts are anticipated to be Low.

7.12.4 32 coral species of conservation importance were recorded from the assessment area in previous and current surveys. Corals were recorded in low abundance and diversity. Most of the species observed were common species found in Hong Kong such as Favites abdita and Outlastrea crispata. Among the recorded species, direct impact is anticipated for 13 coral species of conservation importance. Given that all these species are commonly widespread in Hong Kong waters, recorded in low coverage and are all subjected to existing disturbance from the typhoon shelter, potential impact on coral species is considered to be Low.

7.12.5 To avoid potential indirect impacts to marine environment, water quality mitigation measures (e.g. use of closed grabs for dredging, deployment of silt curtain, etc.) would be implemented during the construction and operation phases.

7.12.6 Enhancement measures such as installing eco-shoreline features on the proposed and modified breakwaters as well as eco-features on VIPS would also be implemented, which could create about 4.75 ha of artificial subtidal hard bottom and about 1380 m of artificial seawall habitats. With proper water mitigation measures in place, it is anticipated that ecological impacts from the Project on the marine environment would be acceptable.

7.13 Reference

Aberdeen Boat Club (2020). Proposed Development at Middle Island - Town Hall Meeting. Assessed in August 2023 at https://www.abclubhk.com/upload/About/MI_Development/2021/ABC-MI-Presentation-THM---V2020-sd.pdf

AFCD (2022). Hong Kong Biodiversity Information Hub.

Carugati, Laura, Lo Martire, Marco,. Gambi, Cristina & Danovaro, Roberto. (2018). Impact of breakwater relocation on benthic biodiversity associated with seagrass meadows of northern Adriatic Sea. Rendiconti Lincei. Scienze Fisiche e Naturali. 29. https://doi.org/10.1007/s12210-018-0720-9.

Chan, A.L.K., Choi, C.L.S., McCorry, D., Chan, K.K., Lee, M.W., Ang, P. (2005). Field guide to hard corals of Hong Kong. Agriculture, Fisheries and Conservation Department. Hong Kong.

DeVantier, L.M., G. De’ath, T.J. Done and Turak, E. (1998). Ecological Assessment of a Complex Natural System: A Case Study from the Great Barrier Reef. Ecological Applications 8:480-496.

DeSalvo, M.K., Estrada, A., Sunagawa, S and Medina, M. (2012). Transcriptomic responses to darkness stress point to common coral bleaching mechanisms. Coral Reefs 31:215-228.

Environmental Protection Department (no date). Map: Water Control Zones. Assessed in August 2023 at https://www.epd.gov.hk/epd/english/environmentinhk/water/hkwqrc/map/watercontrolzone.html

Giglio, V.J., Ternes, M.L.F., Mendes, T.C., Cordeiro, C.A.M.M., & Ferreira, C.E.L. (2017). Anchoring damages to benthic organisms in a subtropical scuba dive hotspot. J Coast Conserv 21, 311–316. https://doi.org/10.1007/s11852-017-0507-7.

IUCN (2024). IUCN Red List Version 2024.2.

MTR Corporation Limited (2010). South Island Line (East).

Ocean Park Corporation (2006). Repositioning and Long Term Operation Plan of Ocean Park.

Ocean Park Corporation (2014). Tai Shue Wan Development at Ocean Park.

Sagerman, J., Hansen, J. P., & Wikström, S. A. (2020). Effects of boat traffic and mooring infrastructure on aquatic vegetation: A systematic review and meta-analysis. Ambio, 49, 517-530.

World Wildlife Fund – Hong Kong (2012). Marine Biodiversity Map.

[1] DeVantier, L.M., G. De’ath, T.J. Done and Turak, E. (1998). Ecological Assessment of a Complex Natural System: A Case Study from the Great Barrier Reef. Ecological Applications 8:480-496.

[2] Ocean Park Corporation (2006) Repositioning and Long Term Operation Plan of Ocean Park

[3] Ocean Park Corporation (2014) Tai Shue Wan Development at Ocean Park

[4] World Wildlife Fund – Hong Kong (2012). Marine Biodiversity Map

[5] MTR Corporation Limited (2010) South Island Line (East)

[6] Aberdeen Boat Club (2020). Proposed Development at Middle Island – Town Hall Meeting. Assessed in August 2023.

[7] DeSalvo, M.K., Estrada, A., Sunagawa, S and Medina, M. (2012). Transcriptomic responses to darkness stress point to common coral bleaching mechanisms. Coral Reefs 31:215-228.

[8] Giglio, V.J et al., (2017) Anchoring damages to benthic organisms in a subtropical scuba dive hotspot. J Coast Conserv 21,311-316

[9] Carugati .L., Marco, L.M., Cristina,G., Roberto, D., (2018). Impact of breakwater relocation on benthic biodiversity associated with seagrass meadows of northern Adriatic Sea. Rendiconti Lincei Scienze Fishiche e Naturali. 29.

[10] Sagerman, J., Hansen, J.P., & Wikström, S. A. (2020). Effects of boat traffic and mooring infrastructure on aquatic vegetation: A systematic review and meta-analysis. Ambio 49,517-530.

7 Ecological Impact

7.1 Introduction

7.2 Environmental Legislation, Standards and Guidelines

7.2.1 This assessment makes reference to the following Hong Kong Special Administrative Region (HKSAR) Government ordinances, regulations, standards, guidelines, and documents that are relevant to ecological impact assessment:

7.2.2 This section also makes reference to the following international conventions and national legislation:

7.3 Assessment Methodology

7.3.2 The ecological characteristics of the assessment area were identified through a comprehensive review of the available literature. This review collated ecological information from various reports and publications, as summarised in Table 7.1 below.

7.3.9 Abundance, biomass, species diversity H’ and evenness J was calculated for pooled data, using the formulae:

H’ = - ∑ ( Ni / N ) ln ( Ni / N ) ; and

J = H’ / ln S

where S is the total number of species in the sample, N is the total number of individuals, and Ni is the number of individuals of the ith species.

7.3.10 Intertidal communities were surveyed at representative survey locations (namely A1 to A9) (Figure 7.1 refers) by line transect method and walk-through survey method, in order to establish an ecological profile of intertidal habitats within the assessment area.

7.4 Description of the Environment

7.4.1 There are no sites of conservation importance located within the assessment area.

7.4.2 Some marine ecological surveys have been conducted in the assessment area under previous studies. The surveyed habitats were primarily dominated by common marine species, as described below.

7.5 Survey Findings

7.5.3 A small patch of natural sandy shore habitat approximately 40 m in length was recorded in the Project site, formed by the tombolo between Ap Lei Chau and Ap Lei Pai, at the western side of the Aberdeen Channel.

7.5.4 Rocky shore habitat was located along the eastern, the southwestern and the western side of the coastline of the Aberdeen Channel, which was a natural habitat. This exposed shore habitat was comprised of bedrock and large boulders.

7.5.6 Spot-check dives were carried out at five sites (Figure 7.1 refers) with corals recorded at four sites (no coral was recorded at Site C5). The water depth along the dive routes ranged from 4.5 m to 11.5 m. Details of coral records from spot-check dives are presented in Table 7.5.

7.5.7 Six 100 m REA transects (REA1 – REA6) were also deployed, which corresponded to spot-check dive routes with corals recorded. The GPS coordinate, maximum depth, bottom substrate and underwater visibility of the REA transect are summarised in Table 7.6.

Fauna Group

No. of individuals

Percentage (%)

Biomass (g)

Percentage (%)

Dry Season

Annelida

148

67.58

7.583

74.68

Arthropoda

12

5.48

0.038

0.37

Echinodermata

13

5.94

0.023

0.58

Mollusca

40

18.26

0.504

4.96

Chordata

2

0.91

1.999

19.69

Nemertea

4

1.83

0.007

0.07

Total

219

100

10.154

100

Wet Season

Annelida

187

61.51

7.461

60.50

Arthropoda

22

7.24

0.149

1.21

Echinodermata

22

7.24

0.042

0.34

Bryozoa

2

0.66

where S is the total number of species in the sample, N is the total number of individuals, and Ni is the number of individuals of the i^th species.