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4. ECOLOGICAL IMPACT ASSESSMENT

4.1 Introduction

4.1.1 This Chapter presents the potential ecological impacts associated with the construction and operation of the Project.

4.2 Environmental Legislation, Criteria and Guidelines

4.2.1 The HKSAR ordinances and regulations relevant to ecological assessment of this Project include the following:

· Country Parks Ordinance (CPO) (Cap. 208) and its subsidiary legislation;

· Forests and Countryside Ordinance (F&CO) (Cap. 96) and its subsidiary legislation, the Forestry Regulations;

· Protection of Endangered Species of Animals and Plant Ordinance (Cap. 586);

· Town Planning Ordinance (TPO) (Cap. 131);

· Wild Animals Protection Ordinance (WAPO) (Cap. 170); and

· Environmental Impact Assessment Ordinance (EIAO) (Cap. 499) and the associated TM (EIAO-TM) in particular Annexes 8 and 16.

4.2.2 Ecological assessment also made reference to the following guidelines and standards as well as international conventions:

· EIA Study Brief ESB-187/2008 - Improvement of Fresh Water Supply to Cheung Chau;

· Hong Kong Planning Standards and Guidelines (HKPSG) Chapter 10, "Conservation";

· EIAO Guidance Note No. 7/2002 – Ecological Baseline Survey for Ecological Assessment;

· EIAO Guidance Note No. 10/2004 – Methodologies for Terrestrial and Freshwater Ecological Baseline Surveys;

· EIAO Guidance Note No. 11/2004 – Methodologies for Marine Ecological Baseline Surveys;

· PELB Technical Circular No. 1/97 - Works Branch Technical Circular No. 4/97, "Guidelines for Implementing the Policy on Off-site Ecological Mitigation Measures";

· Relevant wildlife protection laws in PRC;

· Convention on Wetlands of International Importance Especially as Waterfowl Habitat (the "Ramsar Convention"), which requires parties to conserve and make wise use of wetland areas, particularly those supporting waterfowl populations;

· United Nations Convention on Biological Diversity, which requires parties to regulate or manage biological resources important for the conservation of biological diversity, to promote the protection of ecosystems, natural habitats and the maintenance of viable populations of species in natural surroundings; and

· International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species.

4.3 Study Area

4.3.1 The assessment area for terrestrial ecological impact shall include areas within 500 m distance from the site boundary of the Project and also any other areas likely to be impacted by the Project (Figure 4.1). According to the EIA study brief, the assessment area for marine ecological impact shall be the same assessment area for water quality impact (i.e. Southern Water Control Zone) and also any other areas likely to be impacted by the Project. As this marine ecological assessment area covers a large sketch of sea areas from Waglan Island in the east to Fan Lau in the west, the majority of these sea areas are far away form the project site, and would be unlikely to be impacted by the project at such a small scale. While the baseline conditions have covered a larger sketch especially on marine mammals, the present Ecological Impact Assessment would focus on the waters in the vicinity of the pipeline alignment, i.e. 500 m from the alignment.

4.4 Ecological Key Issues

4.4.1 Key issues of the EIA as stipulated in the EIA Study Brief included but not limited to the following:

Recognised Site of Conservation Importance

· Lantau South Country Park;

Areas with Conservation Interests

· Coastal Protection Areas in Cheung Chau;

Important Habitats

· coral communities (including all hard corals, octocorals and black corals);

· marine benthic communities and intertidal habitats (including rocky shores and sandy shores); and

Species of Conservation Concern

· marine mammals (Finless Porpoise and Chinese White Dolphin).

4.5 Literature Review

4.5.1 Relevant studies including but not limited to the followings were reviewed:

· Hong Kong Biodiversity – Newsletter of Agriculture, Fisheries and Conservation Department (AFCD).

· The Terrestrial Biodiversity Survey conducted by HKU.

· Annual report and other publications of The Hong Kong Bird Watching Society.

· Memoirs of Hong Kong Natural History Society.

· Porcupine! – Newsletter of Department of Ecology & Biodiversity of University of Hong Kong.

· Monitoring of Marine Mammal in Hong Kong Waters – Data Collection (2008-09) Final Report (10 April 2008 to 28 February 2009). (AFCD 2009).

· EIAs approved under the EIAO, including 132 kV Supply Circuit from Pui O via Chi Ma Wan Peninsula via Sea Crossing towards Cheung Chau – EIA Report (Mott 2001).

· Field Guide to Hard Corals of Hong Kong. 1st Edition (Eds. W.C. Chan and Edward Stokes). Friends of the Country Parks and Cosmos Books Ltd, Hong Kong.

· Marine Benthic Communities of Hong Kong (CPCC 2002).

4.5.2 The EIA Study of the CLP’s project “132kV Supply Circuit from Pui O via Chi Ma Wan Peninsula via Sea Crossing towards Cheung Chau” is relevant to the present EIA study as its study area overlapped with a large portion of the Study Area under the present EIA study. Reference was made to the survey results and sighting records of this study.

4.6 Field Survey Scope and Methodology

4.6.1 Five-month ecological field surveys (covering wet season) were undertaken from May to September 2009 to record ecological data within the Study area and establish the ecological profile. The scope of the survey programme covered terrestrial surveys, intertidal surveys, and subtidal surveys. In addition to day-time surveys, night-time surveys were also conducted to record nocturnal fauna including birds, herpetofauna and mammals. Surveys focused primarily on the project site and secondarily on the area within 500 m from the Project site boundary.

4.6.2 Field surveys of marine mammals (Cetaceans) were not conducted. However, the latest results of marine mammal survey conducted by AFCD together with a thorough review of relevant literature are included and are considered sufficient for impact assessment.

4.6.3 Standard sampling technique and appropriate equipment were employed during the ecological surveys for the proposed Project, e.g., Geographic Information System (GIS) and Global Positioning Systems (GPS) for habitat mapping and recording locations of species of conservation concern, high resolution digital camera for photo taking, binoculars and spotting scope for bird surveys, sweep net for butterfly and dragonfly surveys, and SCUBA diving and van-Veen grab for subtidal survey.

4.6.4 Data analyses and discussion described habitats and species found in the Study area, highlighting those that are rare, of conservation concern, or protected by law.

4.6.5 Species groups/habitats surveyed and the detailed survey methodology are described as below, and the Works Programme is provided in Appendix 4.1.

Habitat and Vegetation Survey

4.6.6 Habitats were mapped based on the latest government aerial photos and field ground truthing. Representative areas of each habitat type were surveyed on foot. Plant species of each habitat type encountered and their relative abundance, with special attention to rare or protected species, were recorded. Colour photographs of all habitats encountered on site and of ecological features of special importance were taken. Habitat maps of the site were produced at the required scale using GIS software.

Bird Survey

4.6.7 Both day-time and night-time bird surveys were carried out. Day-time surveys were carried out in the morning, while night-time surveys after dusk. The bird communities of selected habitats within the Study Area were surveyed using the transect count methods during day-time surveys. Locations of sampling transects are shown in Figure 4.1. All birds seen or heard from sampling transects were identified and their abundance recorded. Bird species encountered outside sampling transects but within the Study area were also recorded to produce a complete species list. Signs of breeding (e.g. nests, recently fledged juveniles) were also recorded.

4.6.8 As some birds are nocturnal, night-time surveys were conducted. Nocturnal birds were recorded by searching and records of calling. Ornithological nomenclature in this report followed Carey et al. (2001).

Mammal Survey

4.6.9 Surveys of mammals within the Study area were conducted in daytime and night time. All sightings, tracks, and signs of mammals found were recorded. Nocturnal mammals were actively searched using spot-light. Abundance of flying bats observed during night-time surveys were estimated and presented in ordinal scale. Nomenclature of mammal followed Shek (2006).

Herpetofauna Survey (Reptiles and Amphibians)

4.6.10 Surveys of herpetofauna within the Study area were conducted by focused searches. Both day-time and night-time surveys were carried out. All reptiles and amphibians sighted were recorded. Potential microhabitats of herpetofauna such as wall, fallen logs, litter, underneath of stones or other materials, containers (e.g. pots) were searched to locate cryptic or secretive herpetofauna species. Amphibians were also identified by their calls during night surveys. Nomenclature of amphibians in this report followed Chan et al. (2005) and that of reptiles followed Karsen et al. (1998).

Butterfly and Dragonfly Survey

4.6.11 Dragonfly and butterfly of selected habitats within the Study area were surveyed quantitatively using transect count methods. All dragonflies and butterflies seen from sampling transects were counted. Dragonflies and butterflies encountered outside sampling transects but within the Study area were also recorded in order to produce a complete species list. Nomenclature of dragonfly followed Wilson (2004) and nomenclature of butterfly followed Yiu (2004).

Freshwater Community Survey (Stream Fauna and Aquatic Invertebrate)

4.6.12 Aquatic fauna in stream courses within the Study area were studied according to the site conditions, by various sampling methods including direct observation, focused searching, hand netting, and pot traps. Boulders in the stream were overturned to locate aquatic animals beneath if necessary. All encountered organisms were identified to the lowest possible taxon and recorded. Abundance and species richness of aquatic fauna were provided.

Intertidal Community Survey (Hard and Soft Shores)

4.6.13 Eight sampling sites were surveyed at and in the vicinity of each of the landfall locations, for two times during the study period, for the intertidal habitats including hard and soft shores (Figure 4.1). All intertidal surveys were conducted during suitable ebb tide (< 1m CD). For each sampling site, one transect was deployed for each tidal levels (i.e. high, mid and low). Each transect was surveyed using 5 quadrats of size 0.5m x 0.5m. Epifauna within the quadrats were identified and counted (or recorded with the coverage percentage). For soft intertidal shore community habitat, core sampling method was also used inside each quadrat to locate and identify the presence of animals living within the sediment, after screening with sieves of suitable size. Fauna recorded was assessed for species diversity, abundance and density.

4.6.14 In addition to the quantitative (transect) surveys, qualitative walk-through surveys were also conducted in the survey areas to facilitate the smooth implementation of the ecological surveys, and to help audit the survey findings. This walk-through survey identified the species present and their occurrence and hence facilitated the determination of representative sites for conducting the transect surveys. A walk-through survey along the transect during and after a quantitative sampling event also helped assess whether the sampling exercise has collected representative data (e.g. the number of and type of species encountered) and whether the sampling effort is deemed adequate.

Subtidal Community Survey (Soft-bottom Benthos and Hard-bottom Habitats)

4.6.15 For the soft substrate seabed, subtidal grab sampling was conducted. Six locations covering both the proposed submarine water main alignment and the vicinity (Figure 4.1) were sampled using van Veen grab sampler. Three replicate samples of 0.1m² coverage were taken at each sampling location. Benthic samples were sieved by 0.5mm sieves to separate the fauna from the sediment for subsequent sorting and analysis in the laboratory to assess the species diversity, abundance and density.

4.6.16 For the hard substrate seabed, coral survey was conducted. Qualitative reconnaissance (spot-check) dives were carried out (Figure 4.1) prior to conducting a semi-quantitative survey to identify locations of coral assemblages and composition of hard and soft corals. The semi-quantitative dive surveys were in the form of Rapid Ecological Assessment (REA) (Annex A in Appendix 4.7) to provide information on the abundance and diversity of corals and the exact locations and number of REA transects were determined in accordance with the results of the spot dive. A total of two 100m transects parallel with the shoreline were surveyed along the coast at each site (Figure 4.1). Photographs of representative coral species located in the surveyed areas were taken.

4.7 Key Ecological Issues for the EIA Study

4.7.1 Recognised sites of conservation importance and other areas/habitats of conservation interests within the Study Area include:

· Lantau South Country Park (Figure 4.1);

· Coastal Protection Areas in Cheung Chau (Figure 4.1);

· Important habitats of marine mammals (Chinese white dolphin and finless porpoise); and

· Marine habitats and communities (including corals, benthic and intertidal).

Lantau South Country Park

4.7.2 Lantau South Country Park was designated in 1978 and is the largest country park in the territory. Occupying 56.4 km², it borders with Lantau North Country Park in the north and ends at South Lantau Road in the south. It encompasses a wide range of land habitats, from grassland to some of the finest forest in Hong Kong. The Park has a long coastline, particularly in Chi Ma Wan Peninsula, supporting a wide range of fauna such as insects, reptiles and a variety of birds. The peninsula has extensive plantations which support a great variety of butterflies and birds (AFCD website).

4.7.3 The landfall location at Lantau (i.e. Chi Ma Wan Peninsula) is within the Lantau South Country Park. Without any village development nearby, the surrounding area is generally undisturbed. The only man-made features are the existing fresh water land mains from Silver Mine Bay which crosses the Adamasta Channel to Cheung Chau and the associated valve chamber.

Coastal Protection Areas in Cheung Chau

4.7.4 The natural coasts in north and south Cheung Chau which are largely undisturbed are zoned as Coastal Protection Area (CPA). In addition, two sandy bays along the north-western coast near the works area are also under this zoning to preserve their existing natural landscape. According to the Cheung Chau OZP, the planning intention of this zone is to conserve, protect and retain the natural coastlines and the sensitive coastal natural environment, including attractive geological features, physical landform or area of high landscape, scenic or ecological value, with a minimum of built development.

Important Habitats of Marine Mammals (Chinese White Dolphin and Finless Porpoise)

4.7.5 Within Hong Kong waters, two species of marine mammals are resident year-round: the Chinese white dolphin (Sousa chinensis) and the Finless Porpoise (Neophocaena phocaenoides). Chinese white dolphin is only regularly found to the north and west of Lantau Island. The waters near the pipeline alignment are part of South Lantau water which are used to a lesser extent by Chinese white dolphin (AFCD 2000).

4.7.6 Unlike the Chinese white dolphin, finless porpoises only occur in the southern and eastern waters. Most of the porpoise sightings were made in the offshore waters in South Lantau such as south of Soko Islands.

Marine Habitats and Communities (including Corals, Benthic and Intertidal)

4.7.7 South Lantau waters are basically natural and also habitats for intertidal and subtidal organisms. The shoreline on Chi Ma Wan Peninsula is particularly undisturbed and habours rocky shores and sandy shores.

4.8 Results of Literature Review

Terrestrial Ecology

Habitat / Vegetation

4.8.1 Previous surveys for the EIA Study of the CLP’s project “132kV Supply Circuit from Pui O via Chi Ma Wan Peninsula via Sea Crossing towards Cheung Chau” identified majority the vegetation consists of common species. The following species of conservation concern were recorded near Tai Long Wan (about 1.5 km to the west of the proposed works site at Lantau for the current study): Gmelina chinensis – locally common but protected species in China, and two locally rare species – Cyclobalanopsis glauca and Rhamnus leptophyllus (Mott 2001).

Mammals

4.8.2 Two species of non-flying mammal were recorded from Chi Ma Wan Peninsula by AFCD (Shek et al. 2007). These were Eurasian Wild Pig Sus scrofa and Red Muntjac Muntiacus muntjak. Both species are widely distributed in Hong Kong and are considered very common (ibid.). Red Muntjac is protected under WAPO. This species inhabits shrubland and forest (Shek 2006). No mammal species of conservation concern was recorded in the Study Area of the present EIA study during the ecological surveys for the CLP’s cable circuit EIA (Mott 2001).

4.8.3 Japanese Pipistrelle Pipistrellus abramus was recorded in Ham Tin (about 4 km to the northwest of proposed works site at Lantau for the current study) during the CLP’s cable circuit EIA (Mott 2001). All bats are protected under WAPO.

4.8.4 Roosts of Short-nosed Fruit Bat Cynopterus sphinx and Leschenault’s Rousette Rousettus leschenaulti were reported by AFCD within/near the Study Area in Cheung Chau (Shek and Chan 2005, 2006).

4.8.5 About 11-20 Short-nosed Fruit Bats were found roosting in Chinese Fan-palm around Cheung Kwai Estate on Cheung Chau between April 2004 and July 2005 (Shek and Chan 2006). Short-nosed Fruit Bats construct their own roosts on Chinese Fan-palm by chewing the veins of the large pinnate frond to form a flask-shaped tent. This species has a wide distribution in Hong Kong (Shek 2006).

4.8.6 Roost(s) of Leschenault’s Rousette Rousettus leschenaulti was recorded in sea cave(s) near Tung Wan on Cheung Chau between June 2004 and February 2005. This species has a fairly wide distribution in Hong Kong (Shek 2006).

Avifauna

4.8.7 A total of 47 bird species were recorded in the CLP’s cable circuit EIA study (Mott 2001). Most species were recorded from Pui O, and the majority of recorded species are common and widespread in Hong Kong. Bird species considered of conservation concern included Pacific Reef Egret Egretta sacra, Black Kite Milvus lineatus, Greater Coucal Centropus sinensis, Great Crested Grebe Podiceps cristatus, and Verditer Flycatcher Eumyias thalassina. Great Crested Grebe and Verditer Flycatcher are rare in Hong Kong. Pacific Reef Egret, Greater Coucal and Black Kite are Class 2 Protected Animals of PRC. Black Kite is also listed in Appendix 2 of CITES. All these species were recorded outside the Study Area of the present study.

4.8.8 An Eagle Owl Bubo bubo was found in Chi Ma Wan Peninsula in December 2007 (KFBG 2008). This species is very rare but widespread in Hong Kong (Carey et al. 2001). Eagle Owl utilizes poorly-vegetated boulder-strewn hillsides with grass, low shrubland or scattered pines (ibid.). Nests are built on cliff ledge (Viney et al. 2005). Eagle Owl is Class 2 Protected Animal of PRC and listed in Appendix 2 of CITES.

4.8.9 White-bellied Sea Eagle Haliaeetus leucogaster was sighted in Chi Ma Wan Peninsula during a survey of distribution of this species in Hong Kong conducted by AFCD between November 2001 and May 2003 (Tsim et al. 2003). No nesting of this species was recorded on Chi Ma Wan Peninsula. Sheltered coastal areas with numerous bays and small islands are considered optimal habitats of this species (Tsim et al. 2004). White-bellied Sea Eagle is Class 2 Protected Animal of PRC and listed in Appendix 2 of CITES.

Herpetofauna

4.8.10 Four species of amphibian were recorded during the ecological surveys for the CLP’s cable circuit EIA (Mott 2001). The Chinese Bullfrog Hoplobatrachus chinensis recorded at Pui O was considered of conservation concern. This species is a Class 2 Protected Animal of PRC.

4.8.11 Five species of reptile were recorded during the ecological surveys for the CLP’s cable circuit EIA (Mott 2001). Common Rat Snake Ptyas mucosus recorded in Shap Long Kau Tsuen was considered of conservation concern. This species is listed in Appendix 2 of CITES.

4.8.12 None of these herpetofauna species of conservation concern was recorded in the Study Area of the present study during the ecological surveys for the CLP’s cable circuit EIA (Mott 2001).

4.8.13 Three species of amphibian – Asian Common Toad Bufo melanostictus, Asiatic Painted Frog Kaloula pulchra and Brown Tree Frog Polypedates megacephalus – were recorded from the part of Cheung Chau covered by the Study Area of this study by AFCD (Chan et al. 2005). All these species are very common and widely distributed in Hong Kong (ibid.).

Butterfly and Dragonfly

4.8.14 Thirty-four and seventeen species of butterflies and dragonflies were recorded during the CLP’s cable circuit EIA (Mott 2001) respectively. None of the butterfly or dragonfly species recorded during the ecological surveys for the CLP’s cable circuit EIA (Mott 2001) was considered of conservation concern.

Marine Ecology

4.8.15 At a local level Hong Kong’s territorial waters can be divided into three zones: estuarine, transitional and oceanic. The Study Area falls within the estuarine zone which is influenced by the Pearl River especially during the summer (Morton and Morton 1983).

4.8.16 The marine ecological habitats near the Project area are mainly categorized into rocky shore, sandy shore, hard and soft subtidal habitats, marine water column, and artificial seawalls.

Rocky Shores

4.8.17 Rocky shore organisms originated in purely marine habitats and have evolved and adapted to live on intertidal shores. The extent of their adaptations to this habitat will dictate where they are found on the shore. The more adapted the species is to terrestrial conditions, the higher it will be found. This causes zonation patterns. Their recruitment period and the primary productivity of the shore will affect the abundance of intertidal organisms. Typical exposed rocky shore communities consist of periwinkles, barnacles and limpets. Encrusting algae are common in low intertidal zone (Williams 2003).

4.8.18 Intertidal rocky shore survey was conducted for the CLP’s cable circuit EIA (Mott 2001). Organisms recorded on the shores of Chi Ma Wan Peninsula were largely molluscs. The most abundant being periwinkles (Nodilittorina radiate, N. vidua), limpets (Notoacmaea shrenkii, Patelloida saccharina), chitons (Acanthopleura japonica), barnacles (Tetraclita squamosa) and bivalves (Septifer virgatus).

Sandy Shores

4.8.19 In the lee of headlands or within shallow bays, wave action is reduced and there is an accumulation of sand. Exposed sandy beaches are relatively unstable environments and the fauna is sparse. However, with increasing shelter from direct wave actions, the higher substrate stability allows for accumulation of detrital materials and the development of a rich community of burrowing animals. Typical sandflat communities consist of numerous epifauna and infauna organisms such as burrowing crabs, gastropods, bivalves and worms (Chan and Caley 2003). However all the sandy shores within the 500m distance boundary are mobile sandy beaches. Only one organism, the bivalve Fulvia mutica, was recorded in the sandy shore for the CLP’s cable circuit EIA (Mott 2001).

Hard-Substrate Seabed

4.8.20 Hong Kong’s coral is on the marginal fringe of the great Indo-Pacific reef complex Hong Kong is near the northern limit of climatic conditions suitable for coral. In winter, water temperatures often drop below 15oC, well below that considered optimal for coral development (Scott 1984; Chan et al. 2005).

4.8.21 Although Hong Kong marine environment is not optimal for many coral species to grow, around 84 species of corals can still be found in Hong Kong waters. They mainly grow along the northeastern and eastern shores where the waters are both sheltered and free from the influence of Pearl River. In the southeastern and southern parts of Hong Kong, including Lamma Island, Cheung Chau and Lantau Island, both coral cover and species richness are low. Corals do not form extensive bed and are mostly found as isolated heads among rocks and boulders (AFCD website; Chan et al. 2005). This is reaffirmed by the results of the coral survey at Chi Ma Wan for the CLP’s cable circuit EIA which recorded soft and hard coral assemblages of low abundance and diversity (Mott 2001).

4.8.22 The western water is subject to the massive influence of the Pearl River and is generally unsuitable for coral growth. For the most part, only small isolated colonies of the hardy, encrusting species of Faviidae – Favia, Cyphastrea, Goniastrea or Leptastrea – exist (Scott, P.J.B. 1984). In Cheung Chau, corals are recorded mostly in the northeastern coastal waters (Chan et al. 2005).

4.8.23 A territory-wide dive survey was conducted between 1991 - 1995 in the central and eastern Hong Kong waters (Binnie 1995). Since 2000, AFCD has coordinated annual survey of corals – Hong Kong Reef Check (AFCD website). However, the western waters were not part of the territory-wide survey and Reef Check programme.

4.8.24 Qualitative surveys were carried out at Shek Kwu Chau and Chi Ma Wan in 1997 (Binnie 1997a, 1997b). Both surveys concluded that the hard and soft coral communities are poor in terms of species diversity and abundance. Majority of the hard coral species recorded include the hardy, encrusting species of Faviidae.

4.8.25 Dive surveys were conducted for the CLP cable circuit EIA (Mott 2001) along the Chi Ma Wan Peninsula near Tai Long Wan. The survey location is about 2 km to the southwest of the proposed landfall location. The survey revealed a narrow band of large-medium sized boulders dominated the nearshore subtidal areas at Chi Ma Wan Peninsula. A high sediment deposit was observed on all hard substrate surfaces. Hard and soft corals coverage was extremely low with scattered distribution.

Soft-Substrate Seabed

4.8.26 Except in eastern and southern shores where the shallow subtidal habitat is rocky and coral-encrusted, the majority of subtidal seabed of Hong Kong is soft and comprises an admixture of sand and mud. The detailed composition of the soft sediment varies from place to place and is one of the main factors that determines the type of bottom dwelling (benthic) organisms which inhabits the sediment. Soft sediments support a wide range of bottom-dwelling (benthic) communities and standing crops, and have been long recognized as valuable feeding areas as they are major food source for demersal fishery (AFCD website).

4.8.27 A study of benthic assemblages throughout Hong Kong was undertaken by Shin and Thompson (1982). The study concluded that the western waters of Hong Kong supports assemblages that are polychaete dominated (over 80%).

4.8.28 For the 2001 territorial-wide marine benthic survey (CCPC 2002), polychaete annelids, crustaceans and bivalves were by far the most abundant, comprising over 70% of the total species. The eastern and southern waters are more homogeneous in benthic composition and diversity, and thus reflect relatively higher ecological importance as compared with the other regions. Results of both summer and winter surveys showed minimal seasonal changes in sediment characteristics at the survey stations.

4.8.29 According to the EIA Study for the CLP cable circuit project (Mott 2001), it was suggested that the benthic assemblages between Chi Ma Wan and Cheung Chau (i.e. Admasta Channel) supported relatively low ecological value assemblages.

Artificial Seawall

4.8.30 Part of the coastal areas on Cheung Chau in particular the western shores at the populated central portion have been reclaimed and are lined with vertical seawalls. Few surveys have been conducted on the colonization of organisms on artificial seawalls in Hong Kong, however, fouling organisms have been anecdotally recorded as common on artificial seawalls, wharf piles and other marine structures. The natural communities of artificial embankment follow the zonation of other sheltered shores, with rock oysters, periwinkles, mussels and barnacles being commonly found (Morton and Morton 1983). It can be presumed that such species commonly found on these surfaces in Hong Kong waters will be found on the artificial seawalls within the Study Area.

Marine Waters

4.8.31 The major species to be concerned in the marine waters are the marine mammals. Within Hong Kong waters, two species of marine mammals are resident year-round: the Indo-Pacific hump-backed dolphin (Sousa chinensis) also known as Chinese white dolphin and the finless porpoise (Neophocaena phocaenoides).

4.8.32 All marine mammals found in Hong Kong are protected locally by the Wild Animals Protection Ordinance (Cap. 170). Besides, the Chinese white dolphin is listed as “Near Threatened” in the IUCN Red Data Book while the finless porpoise “Vulnerable”. Both are listed in CITES Appendix I (i.e. highest protection). In China, the Chinese White Dolphin is listed as a “Grade 1 National Key Protected Species” while the finless porpoise is listed as “Grade 2” (AFCD website).

Chinese White Dolphin

4.8.33 The Indo-Pacific hump-backed dolphin (Sousa chinensis), or locally known as Chinese white dolphin is only regularly found to the north and west of Lantau Island. The Deep Bay, East and South Lantau, and Lamma areas are used seasonally and to a lesser extent (AFCD 2000). Waters around Sha Chau, Lung Kwu Chau and north Lantau are heavily used throughout the year (AFCD website). Yearly monitoring studies of Chinese white dolphins in Hong Kong have indicated hotspots consistently used by dolphins in recent years include the waters around Sha Chau and Lung Kwu Chau Marine Park, near Black Point, around the Brothers Island, Sham Shui Kok, and the entire stretch of West Lantau waters from Tai O Peninsula to Fan Lau. These locations are all considered to be prime dolphin habitats in Hong Kong (AFCD 2000, 2009; Jefferson and Leatherwood 1997; Parsons 1998; Jefferson 2000).

4.8.34 The seasonal distribution of the Chinese white dolphin in Hong Kong waters is shown in Figure 4.2. There have been no sightings of dolphins in the waters around the Project site. The marine waters along the pipeline alignment and its vicinity are not part of the habitat frequently used by Chinese white dolphin.

Finless Porpoise

4.8.35 An intensive study of the conservation biology of the finless porpoise (Neophocaena phocaenoides) population in Hong Kong was conducted from 1998 to 2000. The Study revealed porpoises occurred in Hong Kong and adjacent waters year-round, but showed evidence of seasonal movements, with porpoises largely vacating most of Hong Kong’s south western waters in summer and autumn. Seasonal changes in abundance were also evident, with spring as the peak season within Hong Kong waters (Jefferson 2001).

4.8.36 Unlike the Chinese white dolphin, finless porpoises only occur in the southern and eastern waters, but not the north western waters which are influenced by the Pearl River (AFCD website; Jefferson and Braulik 1999). Yearly monitoring of the finless porpoise indicates that most of the porpoise sightings were made in South Lantau. Important porpoise habitats were located just south of Soko Islands, in the offshore waters in South Lantau, in the south western waters of Lamma Island, and around the Po Toi Islands (AFCD 2009). The south western coast of Lamma Island appears to be an area of concentration for the porpoises especially during winter and spring (Jefferson and Braulik 1999).

4.8.37 Seasonal distribution of the finless porpoise in Hong Kong waters is shown in Figure 4.3. The only sightings of finless porpoises near the Project have been mainly in southern Cheung Chau. The marine waters along the pipeline alignment and its vicinity are not frequently used by Finless Porpoise.

4.9 Results of Field Surveys

Project Area

4.9.1 The Project consist of a submarine pipeline, except the two landing points at its two ends and the associated land-based main. The alignment will start at Ha So Pai in the southeastern coast of Chi Ma Wan Peninsula at South Lantau, going through the Adamasta Channel beneath the seabed, and will surface in the northwestern coast of Cheung Chau near Tai Kwai Wan. The landing point on South Lantau is a rocky shore with shrubland-grassland habitat behind, while the landing point at Tai Kwai Wan, Cheung Chau is a reclaimed area extended from the natural headland. The intertdal zone of this reclaimed land is rocky shores which are disturbed and composed of rubbles and concrete blocks. This reclaimed area is currently occupied by two WSD’s works compound, surrounded by some exotic plantation. After making landfall, a section of land-based main will be laid along Cheung Kwai Road and will be connected to Cheung Chau Fresh Water Pumping Station about 100m away from the landing point.

4.9.2 The proposed landfall and works area on Cheung Chau fall on areas zoned as “Government, Institution or Community” (G/IC) on the approved Cheung Chau Outline Zoning Plan (OZP) No. S/I-CC/4.

4.9.3 The central lowland of Cheung Chau contains the development core where most of the existing village areas, commercial uses and major community facilities are concentrated, hence is highly disturbed. The northeastern part of Cheung Chau is largely undeveloped and is covered by a mixture of plantation and grassland-shrubland. There are no natural streams or woodland within the 500m Study Area in Cheung Chau. A number of channelised drains collect upstream flow and village effluent and discharge via outfalls to a sandy beach at Tai Kwai Wan.

4.9.4 Ha So Pai is a remote coastal bay at the southern boundary of Lantau South Country Park. The proposed landfall and temporary works area fall on areas zoned “Country Park” on the approved South Lantau OZP No. S/SLC/15. There are no villages or development in the vicinity of the site except the landfall of the existing 10” and 500 mm submarine mains supplying fresh water from Lantau to Cheung Chau. After making landfall, a section of land-based main will be connected to the nearby existing exposed main on Lantau.

Habitat and Vegetation Survey

4.9.5 Major habitat types recorded within the 500m boundary included plantation, grassland/shrubland, developed area, sandy shore, rocky shore, artificial seawall, and marine waters (Figures 4.4a-c and Figure 4.5).

Table 4.1

Habitats recorded within the Assessment Area

Habitat	Size (ha or m)	Percentage Total (%)
Developed Area	19.05 ha	8.3
Marine Waters	141.64 ha	61.9
Plantation	25.47 ha	11.1
Shrubland-Grassland	38.17 ha	16.7
Rocky Shore	1520 m	1.0
Sandy Shore	363 m	0.8
Artificial Seawall	554 m	0.2

4.9.6 A total of 179 plant species was recorded (Appendix 4.2), 55 of which were exotic species. Three tree species of conservation concern were recorded. They are Thespesia populnea, Celtis biondii, Ficus tinctoria subsp. gibbosa (Figure 4.4). They are of restricted distribution in Hong Kong, although none are protected under local or regional regulations.

Plantation

4.9.7 Plantation habitat within the Study Area is semi-natural and young with a 8-12m canopy of planted trees and naturally colonised understorey. The plant diversity was low to moderate; 106 species were recorded. Plantation on hillside of Chi Ma Wan peninsula was dominated by Pinus massoniana and Acacia confusa. The understorey was colonised with native ferns, shrubs and trees including Dicranopteris pedata, Rhodomyrtus tomentosa, Schefflera heptaphylla and Rhus succedanea. Plantation at Cheung Chau was also located on wooded hillside as well as along engineering slopes and roads. Species commonly recorded included Casuarina equisetifolia, Acacia confusa and Leucaena leucocephala. The understorey was moderately colonised with native shrubs and trees including Psychotria asiatica, Macaranga tanarius, Schefflera heptaphylla and Microcos paniculatus. A few plots of lands among plantation in Cheung Chau were planted with fruit trees including banana, pineapple, and papaya. The footprint of these farming lots were very small and therefore not mapped separately.

4.9.8 Two tree species of conservation concern, Celtis biondii, Ficus tinctoria subsp. gibbosa were recorded in plantation. A few young saplings of Celtis biondii were found along a footpath up to the water works station at Chi Ma Wan peninsula. It is a lowland forest species usually found nearly coastal area (Xing et al. 2000). A few mature individuals of Ficus tinctoria subsp. gibbosa was found on hillslope near an elderly home at Cheung Chau. It is usually seen on rocks near villages (ibid.).

Shrubland-grassland

4.9.9 Shrubland-grassland, probably maintained by hillfires from scattered grave sites, occupied about half of the terrestrial part of the Study Area. Major species recorded included Dicranopteris pedata, Rhodomyrtus tomentosa, Rhaphiolepis indica, and Schefflera heptaphylla. A total of 56 species with no plants of conservation interest was recorded.

Developed Area

4.9.10 Villages, roads, footpaths, and utility facilities including service reservoir, radar station and sewage pumping station largely on Cheung Chau constituted the Developed Area. Plant species recorded are mainly of exotic and common pioneer species including Acacia confusa, Leucaena leucocephala and Macaranga tanarius. Most are landscape plantings in amenity areas and among residential areas. A total of 58 species with no plants of conservation interest was recorded.

Rocky Shore

4.9.11 Natural rocky shores formed by large boulders and pebbles were located on both Chi Ma Wan peninsula and Cheung Chau. Only a few plant species colonised in crevices with sediments. Parts of the rocky shores at both landfall sites were partly modified.

Sandy Shore

4.9.12 Sandy shores were found at Tai Kwai Wan, Tung Wan on Cheung Chau and north of Ha So Pai on Chi Ma Wan peninsula. Due to road and village house development, Tung Wan were void of natural backshore vegetation, with some exotic trees including Leucaena leucocephala. The sandy shore on Chi Ma Wan peninsula was fairly intact. Backshore and coastal plant species recorded included Hibiscus tiliaceus, Scaevola sericea and Pandanus tectorius. A restricted backshore tree species, Thespesia populnea was also recorded here.

Artificial Seawall

4.9.13 There was no artificial seawalls on Chi Ma Wan peninsula, but sloping boulder seawalls could be found at the eastern and western ends of the 500m Study Area on Cheung Chau side. These seawalls included the waterfronts of a sewage treatment plant, and a refuse transfer station.

Marine Waters

4.9.14 Marine waters within the Study Area comprise three sub-types of habitats, i.e. water column, soft-substrate seabed, and hard-substrate seabed. Marine waters in the vicinity of Cheung Chau is within the estuarine zone and influenced by Pearl River discharge.

Bird Survey

4.9.15 Thirty species of birds were recorded within the Study Area (Appendix 4.3). The majority of the recorded species are common and widespread in Hong Kong. Most (61.9% of total) of the Study Area is covered by marine waters. The rest of the Study Area is covered by developed area, plantation and shrubland-grassland habitat. These habitats generally support low abundance of avifauna.

4.9.16 Both bird abundance and species richness are very low in rocky shore and sandy shore, and low in plantation. Bird abundance is low to moderate in shrubland-grassland and developed area, and species richness in these two types of habitats is low. No sign of breeding on any bird species was observed within the Study Area during the surveys.

4.9.17 Bird species of conservation concern included Pacific Reef Egret Egretta sacra, White-bellied Sea Eagle Haliaeetus leucogaster, Black Kite Milvus lineatus, Greater Coucal Centropus sinensis and Hwamei Garrulax canorus. All these species except Hwamei are Class 2 Protected Animals of PRC. White-bellied Sea Eagle, Black Kite and Hwamei are listed in Appendix 2 of CITES.

4.9.18 Solitary individuals of Pacific Reef Egrets were observed at rocky shores of Chi Ma Wan and sandy shores of Cheung Chau. This species is common and widespread in Hong Kong and mainly occurs in rocky shores (Viney et al. 2005). Pacific Reef Egret nests among rocks near the tide line. No nest or sign of breeding of this species was observed in the Study Area.

4.9.19 An individual of White-bellied Sea Eagle was observed flying across the coastline of Chi Ma Wan. This species mainly forages in coastal waters. Most breeding pairs of White-bellied Sea Eagle are located in eastern waters of Hong Kong (Tsim et al. 2004). Sheltered coastal areas with numerous bays and small islands are considered prime habitats of White-bellied Sea Eagle (ibid.). No nest of White-bellied Sea Eagle was found within the Study Area.

4.9.20 Solitary individuals of Black Kites were observed soaring above plantations at Chi Ma Wan and Cheung Chau, as well as developed area, sandy shore and shrubland-grassland at Cheung Chau. Black Kite is very common in Hong Kong, and occurs in many types of habitats (Viney et al. 2005).

4.9.21 Greater Coucal were recorded from plantations and shrublands at both Chi Ma Wan and Cheung Chau. Greater Coucal is very common in Hong Kong. This species is widespread in Hong Kong, and occurs in many types of habitats (Viney et al. 2005).

4.9.22 Hwamei were recorded from shrubland-grassland at Cheung Chau. This species is common in Hong Kong, and widely distributed in hillsides covered by shrublands (Viney et al. 2005).

Mammal Survey

4.9.23 Two species of bats were recorded within the Study Area (Appendix 4.4). These were Japanese Pipistrelle Pipistrellus abramus and Short-nosed Fruit Bat Cynopterus sphinx. Both species are common in Hong Kong (Shek 2006). All bats are protected under WAPO in Hong Kong.

4.9.24 No non-flying mammals or their signs were recorded within the Study Area.

Herpetofauna Survey (Reptiles and Amphibians)

4.9.25 Five species of amphibians were recorded in the Study Area (Appendix 4.4). These included Asian Common Toad Bufo melanostictus, Asiatic Painted Frog Kaloula pulchra, Marbled Pygmy Frog Microhyla pulchra, Gunther’s Frog Rana guentheri and Brown Tree Frog Polypedates megacephalus. All these species are common and widespread in Hong Kong (Chan et al. 2005). These frogs were recorded from ditches and gullies, and were present in low abundance. The low diversity of amphibian was related to the paucity of freshwater habitat within the Study Area.

4.9.26 Four species of reptiles were recorded in the Study Area (Appendix 4.4). These included Chinese Gecko Gekko chinensis, Tokay Gecko Gekko gecko, Reeves’s Smooth Skink Scincella reevesii and Changeable Lizard Calotes versicolor. All except Tokay Gecko are common and widespread in Hong Kong. Tokay Gecko is a Class 2 Protected Animal of PRC and is rare in Hong Kong, and usually found in thick shrubland and forest (ibid.). This species is recorded from scattered locations in Hong Kong, e.g., Tung Chung, Lion Rock, and was recorded in the plantation in Chi Ma Wan during the survey for the present EIA study.

Butterfly and Dragonfly Survey

4.9.27 Thirty-five species of butterflies were recorded within the Study Area (Appendix 4.5). Most of the recorded species were common and widespread in Hong Kong (Yiu 2004). Indian Palm Bob Suastus gremius and Common Redeye Matapa aria are uncommon, while Red Lacewing Cethosia biblis is rare in Hong Kong (ibid.).

4.9.28 Both butterfly abundance and species richness are very low in rocky shores and sandy shores, and low in developed area. Species richness is low to moderate in shrubland-grassland and plantation. Butterfly abundance is low in shrubland-grassland, and low to moderate in plantation.

4.9.29 Among the recorded butterfly species, only Red Lacewing was considered of conservation concern. Two individuals of this species were recorded at shrubland in Cheung Chau. Though considered as a rare species, Red Lacewing is still recorded from a number of localities in Hong Kong, and mainly occurs in young secondary growths (Bascombe et al. 1999, Yiu 2004).

4.9.30 Fourteen species of dragonflies were recorded within the Study Area (Appendix 4.6). All recorded species are common and widespread in Hong Kong (Wilson 2004). Species richness of dragonfly was low in all types of habitats within the Study Area. The low diversity of dragonfly in the Study Area was due to the lack of aquatic habitat. Abundance of dragonfly is very low in rocky shore and sandy shore, low in stream, shrubland-grassland, developed area and plantation.

Freshwater Community Survey

4.9.31 One water course was shown within the Study Area on the slope at Chi Ma Wan side on survey map, but was found to be dry during the survey. This water course is very steep in profile and might drain the surface flow from the small hill slope above during raining. No aquatic fauna was found in this water course.

4.9.32 Similarly there was no natural stream within the 500m Study Area in Cheung Chau. But a steep gully and a number of channelised drains collect upstream flow and village effluent and discharge via outfalls to a sandy beach at Tai Kwai Wan. There was no aquatic fauna in this gully and drains, except a section of outfall outside the residential development of Scenic Garden behind Tai Kwai Wan. The outfall was immediately seawards to the residential development and received surface runoff discharges from underground drains. As the outfall section was under the tidal influence, low abundance of some brackish species such as Crab Varuna littarata could be found inside. But this section of outfall was not considered a stream habitat as it only receives flows from underground drains.

Intertidal Community Survey (Hard and Soft Shores)

4.9.33 No species of conservation importance was recorded in intertidal habitats (neither hard nor soft shore habitats) during the survey for the present EIA study (Appendix 4.7). The rocky shore habitat on Chi Ma Wan was typical natural rocky shore of continuous bedrock. Dominant species included Rock oyster Saccostrea cucullata, Acorn barnacle Tetraclita squamosa, Stalked barnacle Capitulum mitella, and Black mussel Septifer virgatus. All these species are common and abundant species on typical rocky shore habitats. Though absent from Chi Ma Wan, there were a considerable length of artificial seawalls on Cheung Chau side. Though of similar species composition as in rocky shores, the diversity and the abundance of intertidal fauna on these artificial seawalls were very low.

4.9.34 The fauna on sandy shores were sparse. Only Ghost crab Ocypode sp. and Clam Donax sp. were recorded on the sandy beaches on both Cheung Chau and Chi Ma Wan sides. Both are common and typical fauna on sandy beaches.

Subtidal Community Survey (Soft-bottom Benthos and Hard-bottom Habitats)

4.9.35 Soft-bottom seabed habitat was investigated by grab sampling, and the results revealed that no species of conservation importance was found in the area (Appendix 4.7).

4.9.36 For hard-bottom seabed habitats, no coral was recorded on the Cheung Chau side landfall location, while a very low coverage (less than 1%) of stony corals was found at the Chi Ma Wan side shore (Appendix 4.7). Recorded species included Plesiastrea versipora, Favia speciosa, Oulastrea crispate, and Goniopora stutchburyi. Plesiastrea versipora and Favia speciosa are abundant in Hong Kong, while Oulastrea crispate and Goniopora stutchburyi are common in Hong Kong (Chan et al. 2005).

4.10 Evaluation of Habitats and Species

4.10.1 The ecological importance of the habitats within the 500m assessment area was evaluated in accordance with the criteria stipulated in Annex 8 of EIAO-TM.

4.10.2 Fauna species recorded in the field surveys were judged whether it is of conservation concern based on the criteria including protection status (e.g. fauna protected under WAPO (except birds), and flora and fauna protected under regional/global legislations/conventions), species distribution (e.g. endemic), and rarity (e.g. rare or restricted). These criteria are relevant to those in Table 3, Annex 8 of the EIAO-TM.

Table 4.2

Evaluation of Plantation Habitat within the Assessment Area

Criteria	Description
	Chi Ma Wan	Cheung Chau
Naturalness	Semi-natural habitat, planted canopy trees with natural colonised understory.	Semi-natural habitat, planted canopy trees with natural colonised understory.
Size	8.65 ha	16.82 ha
Diversity	Low to moderate for plants. Low bird and dragonfly diversity, low to moderate butterfly diversity.	Low to moderate for plants. Low bird and dragonfly diversity, low to moderate butterfly diversity.
Rarity	No rare or protected plant species recorded. Fauna species of conservation concern included Japanese Pipistrelle, Short-nosed Fruit Bat and Tokay Gecko.	No rare or protected plant species. Two restricted tree species, Thespesia populnea and Ficus tinctoria subsp. gibbosa, recorded. Fauna species of conservation concern included Black Kite and Great Coucal.
Re-creatability	Easy to create	Easy to create
Fragmentation	Fairly intact.	Scattered among developed areas.
Ecological linkage	Not functionally linked to any habitat of conservation importance	Not functionally linked to any habitat of conservation importance
Potential value	Moderate to high given time and control of disturbance	Limited due to human disturbance.
Nursery/breeding ground	No significant record. May provide breeding habitats for birds, reptiles and butterflies.	No significant record. May provide breeding habitats for birds, reptiles and butterflies.
Age	Young	Young
Abundance/richness of wildlife	Low bird and dragonfly abundance, low to moderate butterfly abundance.	Low bird and dragonfly abundance, low to moderate butterfly abundance.
Overall ecological value	Low to Moderate	Low to Moderate

Table 4.3

Evaluation of Shrubland-Grassland Habitat within the Assessment Area

Criteria	Description
	Chi Ma Wan	Cheung Chau
Naturalness	Semi-natural habitat	Semi-natural habitat
Size	19.27 ha	18.9 ha
Diversity	Low flora diversity. Low terrestrial fauna diversity.	Low flora diversity. Low terrestrial fauna diversity.
Rarity	None for plants. Fauna species of conservation concern included Black Kite and Greater Coucal.	None for plants. Fauna species of conservation concern included Greater Coucal, Hwamei and Red Lacewing.
Re-creatability	Maintained by hillfire	Maintained by hillfire
Fragmentation	Isolated stands on grassy hillsides	Fairly intact
Ecological linkage	Not functionally linked to habitats of conservation importance	Not functionally linked to habitats of conservation importance
Potential value	Low due to presence of grave sites	Low due to presence of grave sites
Nursery/breeding ground	No significant record. May provide breeding habitats for birds, reptiles and butterflies.	No significant record. May provide breeding habitats for birds, reptiles and butterflies.
Age	N/A	N/A
Abundance/richness of wildlife	Low to moderate bird and dragonfly abundance, low dragonfly abundance.	Low to moderate bird and dragonfly abundance, low dragonfly abundance.
Overall ecological value	Low	Low

Table 4.4

Evaluation of Developed Area within the Assessment Area

Criteria	Description
	Chi Ma Wan	Cheung Chau
Naturalness	Man made habitat	Man made habitat
Size	0.21 ha	18.85 ha
Diversity	Low flora and fauna diversity.	Low flora and fauna diversity.
Rarity	None recorded for plant species. None recorded for fauna species.	None recorded for plant species. Fauna species of conservation concern included Japanese Pipistrelle, Black Kite and Greater Coucal.
Re-creatability	Easy to recreate	Easy to recreate
Fragmentation	N/A	N/A
Ecological linkage	Not functionally linked to habitats of conservation importance	Not functionally linked to habitats of conservation importance
Potential value	Low	Low
Nursery/breeding ground	No significant record. Limited due to the high disturbance level.	No significant record. Limited due to the high disturbance level.
Age	N/A	N/A
Abundance/richness of wildlife	Low to moderate bird abundance, low butterfly and dragonfly abundance	Low to moderate bird abundance, low butterfly and dragonfly abundance
Overall ecological value	Low	Low

Table 4.5

Evaluation of Sandy Shore within the Assessment Area

Criteria	Description
	Chi Ma Wan	Cheung Chau
Naturalness	Natural	Natural, but backshore modified at Tai Kwai Wan and Tung Wan.
Size	143 m	220 m
Diversity	Very low diversity on plant, bird, butterfly, and intertidal fauna, low dragonfly diversity.	Very low diversity on plant, bird, butterfly, and intertidal fauna, low dragonfly diversity.
Rarity	One restricted tree species Thespesia populnea recorded. Fauna species of conservation concern included Pacific Reef Egret	No rare or protected plant species recorded. Fauna species of conservation concern included Pacific Reef Egret and Black Kite
Re-creatability	Difficult to recreate	Difficult to recreate
Fragmentation	Fairly intact	Fairly intact
Ecological linkage	Not functionally linked to habitats of conservation importance	Not functionally linked to habitats of conservation importance
Potential value	Low	Low, high disturbance level from visitors
Nursery/breeding ground	No significant record. Limited due to tidal influence.	No significant record. Limited due to tidal influence.
Age	N/A	N/A
Abundance/richness of wildlife	Very low abundance on both terrestrial and intertidal fauna	Very low abundance on both terrestrial and intertidal fauna
Overall ecological value	Low	Low

Table 4.6

Evaluation of Rocky Shore within the Assessment Area

Criteria	Description
	Chi Ma Wan	Cheung Chau
Naturalness	Natural, but partly modified at the landfall location	Natural, but partly modified at the landfall location
Size	986 m	534 m
Diversity	Very low plant diversity, very low bird and butterfly diversity, low dragonfly diversity.	Very low plant diversity, very low bird and butterfly diversity, low dragonfly diversity.
Rarity	No rare or protected plant species recorded. Fauna species of conservation concern included Pacific Reef Egret and White-bellied Sea Eagle.	No rare or protected plant species recorded. None recorded for fauna species.
Re-creatability	Difficult to recreate	Difficult to recreate
Fragmentation	Fairly intact	Fairly intact
Ecological linkage	Not functionally linked to habitats of conservation importance	Not functionally linked to habitats of conservation importance
Potential value	N/A	N/A
Nursery/breeding ground	No significant record.	No significant record.
Age	N/A	N/A
Abundance/richness of wildlife	Very low terrestrial fauna abundance. Moderate abundance of intertidal fauna.	Very low terrestrial fauna abundance. Low abundance of intertidal fauna
Overall ecological value	Low	Low

Table 4.7

Evaluation of Artificial Seawall within the Assessment Area

Criteria	Description
Naturalness	Man-made habitat
Size	554 m (all on Cheung Chau portion)
Diversity	Void of vegetation, very low terrestrial fauna abundance.
Rarity	None recorded
Re-creatability	Easy to recreate
Fragmentation	Around utility facility along the coast
Ecological linkage	Not functionally linked to habitats of conservation importance
Potential value	N/A
Nursery/breeding ground	No significant record. Limited due to lack of vegetation cover and tidal influence.
Age	N/A
Abundance/richness of wildlife	Very low terrestrial fauna abundance.
Overall ecological value	Low

Table 4.8

Evaluation of Marine Waters within the Assessment Area

Criteria	Description
	Hard-substrate seabed	Soft-substrate seabed	Water column
Naturalness	Comprising both natural (i.e. along rocky shores) and artificial (i.e. along seawalls)	Natural habitat	Natural habitat
Size	141.64 ha
Diversity	Low diversity, only four species of hard corals	Low		Low
Rarity	All recorded coral species are either abundant or common in Hong Kong	No species of conservation importance was recorded		No sighting record of marine species of conservation importance such as Finless Porpoise.
Re-creatability	Able to re-create	Difficult to create		Difficult to create
Fragmentation	Not fragmented	Not fragmented		Not fragmented
Ecological linkage	Physically connected with adjoining natural marine habitats	Physically connected with adjoining natural marine habitats		Physically connected with adjoining natural marine habitats
Potential value	Low	Low		Low
Nursery/breeding ground	Not known to be of special importance as nursery / breeding ground	Not known to be of special importance as nursery / breeding ground		Part of the nursery areas of commercial fisheries resources.
Age	NA	NA		NA
Abundance/richness of wildlife	Very low coverage of hard corals	Low abundance of infauna		Not frequently use by marine mammals such as Finless Porpoise.
Overall ecological value	Low to Moderate	Low		Low

Table 4.9

Evaluation of Floral Species of Conservation Concern within the Study Area

Common Name	Scientific Name	Locations	Protection Status	Distribution	Rarity
Humped Fig Tree	Ficus tinctoria subsp. gibbosa	Plantation at Cheung Chau	Not protected	In forest or on rocks near villages	Restricted
Biond’s Hackberry	Celtis biondii	Plantation at Chi Ma Wan	Not protected	Low forest especially near coastal area	Restricted
Portia Tree	Thespesia populnea	Sandy Beach at Chi Ma Wan	Not protected	Coastal area	Restricted
		Plantation at Cheung Chau

Table 4.10

Evaluation of Faunal Species of Conservation Concern within the Study Area

Common Name	Scientific Name	Locations	Protection Status	Distribution	Rarity
Japanese Pipistrelle	Pipistrellus abramus	Woodland at Chi Ma Wan; developed area in Cheung Chau	WAPO	Widely distributed in Hong Kong	Common in Hong Kong
Short-nosed Fruit Bat	Cynopterus sphinx	Woodland at Chi Ma Wan	WAPO	Widely distributed in Hong Kong	Common in Hong Kong
Pacific Reef Egret	Egretta sacra	Sandy Shore at Chi Ma Wan and Cheung Chau; Rocky shore at Chi Ma Wan	WAPO; Class 2 Protected Animal of PRC	Widely distributed in Hong Kong	Common in Hong Kong
White-bellied Sea Eagle	Haliaeetus leucogaster	Flying across the seashore of Chi Ma Wan	WAPO; Class 2 Protected Animal of PRC; Appendix 2 of CITES	Mainly found in eastern waters of Hong Kong	Uncommon, about 8 pairs breed in Hong Kong
Black Kite	Milvus lineatus	Plantation , developed area, sandy shore and shrubland-grassland at Cheung Chau; Shrubland-grassland at Chi Ma Wan	WAPO; Class 2 Protected Animal of PRC; Appendix 2 of CITES	Widely distributed in Hong Kong	Common in Hong Kong
Greater Coucal	Centropus sinensis	Plantation and developed area in Cheung Chau; Shrubland-grassland at Chi Ma Wan and Cheung Chau.	WAPO; Class 2 Protected Animal of PRC	Widely distributed in Hong Kong	Common in Hong Kong
Hwamei	Garrulax canorus	Shrubland-grassland at Cheung Chau	WAPO; Appendix 2 of CITES	Widely distributed in Hong Kong	Common in Hong Kong
Tokay Gecko	Gekko gecko	Plantation at Chi Ma Wan	Class 2 Protected Animal of PRC	Found in scattered locations in Hong Kong	Rare in Hong Kong
Red Lacewing	Cethosia biblis	Shrubland-grassland at Cheung Chau	Nil	Recorded from a number of localities in Hong Kong	Rare in Hong Kong
Hard corals	Plesiastrea versipora, Favia speciosa, Oulastrea crispate, and Goniopora stutchburyi.	Hard-bottom seabed near Chi Ma Wan landing point	Cap. 586	Widely distributed in Hong Kong, but mainly in the eastern oceanic zone.	All four recorded species are either abundant or common in Hong Kong.

4.11 Impact Identification and Evaluation

4.11.1 The Project will comprise the followings:

· Laying of submarine water main of approximately 1400m in length and 500mm in diameter across Adamasta Channel;

· Construction of landfall and associated works within Lantau South Country Park, Lantau Island; and

· Construction of landfall and associated works near Tai Kwai Wan, Cheung Chau.

4.11.2 The potential ecological impacts caused by the project are identified and evaluated below. The main impact will occur during construction phase only. As the completed water main will be underground, and used to convey treated water from Lantau to Cheung Chau only, no maintenance of the water main is anticipated necessary during the operation phase. Therefore no ecological impact is expected during operational phase.

Terrestrial Ecology

Chi Ma Wan Peninsula

4.11.3 The proposed works area in Lantau will be located at a rocky shore adjacent to the landfall of the existing submarine main which has been partly covered with concrete. Of the 427m² rocky shore habitat above high water mark to be resumed, about 6m² will be concreted to support the landfall of the proposed water main, while about 32m² will be occupied by an elevated platform as a temporary works area. The alignment of the land-based main is to be finalised in the detailed design stage. It would be connected to the existing land-based main currently being under replaced.

4.11.4 Though the works area falls with the boundary of Lantau South Country Park, only a few common plant species grown on the rocky shore would be affected, and the vegetation within the Lantau South Country Park will largely be left undisturbed. No flora of conservation interest would be affected by the Project. Potential impact on the habitats and associated vegetation is ranked as minimal. No mitigation other than good site practice is required.

4.11.5 Among the fauna species of conservation concern listed in Table 4.10, only White-bellied Sea Eagle and Pacific Reef Egret mainly utilise coastal habitats. The others are terrestrial fauna. The proposed Project will only affect small area of rocky shore, which accounts for an insignificant proportion of the daily range of these two species. The potential impact to White-bellied Sea Eagle and Pacific Reef Egret is ranked as minimal.

4.11.6 Disturbance aroused from construction works will be small scale, short-term and localised. Potential impact to fauna species of conservation concern will be minimal.

Cheung Chau

4.11.7 The proposed works area in Cheung Chau is located in G/IC zone with developed area and plantation which are currently occupied by two contractor works compounds for temporary storage of construction materials and would be occupied by various water works associated facilities including storage compound, tanks, construction equipment and site offices. Habitat loss is therefore considered permanent. Both habitats are of low ecological values, and only common or exotic plant species would be affected. The Coastal Protection Area will not be impacted by the Project.

4.11.8 After making landfall, the proposed land-based main will be laid along Cheung Kwai Road and existing village access track. The temporary works area includes a 1.2m wide trench to be dug along the land-based main on the road which would be back-filled after construction. No mitigation other than good site practice is required.

4.11.9 Due to the high disturbance level, the affected habitats in Cheung Chau are not important habitats of the fauna of conservation concern listed in Table 4.10. Disturbance aroused from construction works will be small scale, short-term and localised. The potential impact to these fauna is ranked as minimal.

4.11.10 A summary of habitat loss is provided in Table 4.11 below.

Table 4.11

Habitat Loss caused by the Project

Location	Permanent Loss (m^2)			Temporary Disturbance (m^2)
	Developed Area	Plantation	Rocky Shore	Developed Area	Plantation	Rocky Shore
Cheung Chau	1166	864	-	224	-	-
Chi Ma Wan Peninsula	-	-	6	-	-	32

Marine Ecology

4.11.11 The proposed works area at the Lantau landfall is on partially modified rocky shore, and is about 15m from the waterfront. Given the steeper profile of a rocky shore, it is thus located at high elevation above the high water mark (inside the splash zone). Different from the eulittoral zone below which is under a certain time of submersion everyday and more cracks can be found among the rocks (which facilitate intertidal organisms to colonise), the splash zone is harsh for intertidal organisms due to the prolonged desiccation and high temperature. As a result, the splash zone is usually sparse in or sometimes even void of intertidal fauna. At 15 m distance from the waterfront, there were only littorid snails in the lower portion of the works area while the upper portion are not colonised by intertidal fauna. The littorid snails are among the most common and widespread intertidal fauna on rocky shores in Hong Kong. The impact on intertidal fauna and community is thus minimal. Indirect impact such as change in water quality from site runoff is also minimal as there would not be significant earth works to be conducted. Underwater noise is not a concern as the construction involves no impact–driven process, and thus no significant noise impact is anticipated.

4.11.12 The works area at Cheung Chau is located at a headland with rocky shore. But different from the natural coastline at Lantau, this headland was not natural, but was previously reclaimed and formed by rock fill. The rocky shore at this headland was also composed of rock fill materials rather than natural bedrock or boulders, and is thus not a natural habitat. The survey results indicated that the intertidal fauna on the headland were very low in both abundance and diversity, and of low ecological value. Furthermore, the works area here will be away from the intertidal zone and thus no significant impact on intertidal ecology is anticipated.

4.11.13 There are sandy shores located within 500 m distance at Cheung Chau and Lantau sides. But no sandy shores will be encroached by the Project, and the survey results have indicated the sandy shores were of low ecological value due to very low diversity of fauna.

4.11.14 The only subtidal species of concern recorded during the surveys are the common species of hard corals of very low coverage at Lantau coastlines. There will be no direct impact on any subtidal habitats including hard-substrate seabed, soft-substrate seabed, and marine waters, as the pipeline will be a submarine pipeline and constructed by horizontal directional drilling method. The drilling works will be conducted within bedrock layer and the seabed will not be disturbed. The marine waters along the pipeline alignment and its vicinity are not frequently used by Chinese White Dolphin or Finless Porpoise. No significant impact on subtidal ecology is therefore anticipated.

4.12 Impact Avoidance and Mitigation Measures

Impact Avoidance and Minimisation

4.12.1 The proposed water main will be laid across Adamasta Channel using horizontal directional Drilling (HDD) method. The drilling works will be conducted within bedrock layer and the seabed will not be disturbed, hence avoiding impact to marine habitat.

4.12.2 The land resumption boundary at Chi Ma Wan peninsula has been refined to avoid encroachment and potential impact on terrestrial vegetation and the rocky shore concerned. The temporary works area is also located near the existing main which is within the splash zone and the surface has already been partially concreted. It will be constructed in form of a temporary elevated platform to minimise disturbance on the rocky shore and would be reinstated after construction. The footprint of the permanent supporting structure is also minimised to minimise the impact on rocky shore habitat.

4.12.3 The site boundary of the Project at Cheung Chau has also been fine-tuned to avoid encroachment or disturbance to the man-made origin rocky shore habitat, Coastal Protection Area and plant of conservation interest in the vicinity. The land-based main would also be aligned under existing road to minimise disturbance to surrounding habitat.

4.12.4 Good site practices should be implemented to avoid encroachment onto the nearby natural habitats, minimise disturbance to wildlife and ensure good water quality. Examples of water quality mitigation measures and waste management measures are detailed in Sections 3.7 and 7.6 of the EIA report respectively. Other good site practices include:

· Works within Lantau South Country Park should be carried out strictly within the approved location.

· No vegetation within Lantau South Country Park should be unnecessarily disturbed. All workers should be regularly briefed to avoid disturbing the flora and fauna near the works area. Impact on the rocky shore concerned should be minimized as far as possible.

· No refuse should be left within Lantau South Country Park overnight. All refuse should be properly packed and removed from site daily.

· The proposed launching site at Cheung Chau should be properly bunded to contain and divert site runoff to adequately designed wastewater treatment facilities.

· The retained trees at Cheung Chau launching site should be properly protected during construction.

Impact Mitigation

4.12.5 The overall ecological impact is ranked as minor, and no specific ecological mitigation is required.

4.13 Residual and Cumulative Ecological Impacts

4.13.1 Net loss of rocky shore habitat at Chi Ma Wan peninsula and plantation at Cheung Chau would constitute the residual impact. However, due to small footprint of loss (<10m² of rocky shore) and low ecological value of the plantation habitat at Cheung Chau, the residual impact is considered acceptable.

4.13.2 Based on current information, the potential concurrent project will be the construction of village sewers in Cheung Chau (see Section 2.6). As the sewerage works are expected to be small scale and will be constructed within disturbed village areas, cumulative ecological impact is not expected.

4.14 Ecological Monitoring and Audit

4.14.1 Given the limited sizes of the works areas, the ecological value of the habitats affected by the works areas, and the low disturbing construction method used for laying the water main, no specific ecological monitoring is required during construction phase.

4.14.2 The weekly site audit undertaken by the Environmental Team should ensure the recommended good site practices are properly implemented. For example, the Cheung Chau launching site would be checked to make sure it is properly bunded, the retained trees are properly protected and are not adversely affected by construction works. The site audit at Lantau should check to ensure the works in Lantau South Country Park are being carried out in accordance with the approved location and that no vegetation in the Country Park is being disturbed.

4.15 Summary

4.15.1 The Project has avoided and minimized much of the ecological impacts by adopting the HDD construction method in laying submarine water main. Works at Lantau has been minimized to avoid impacts to Lantau South Country Park.

4.15.2 Ecological resources recorded within the 500m study area included plantation, grassland/shrubland, developed area, sandy shore, rocky shore, artificial seawall, marine waters and its associated flora and fauna species. Apart from plantation and hard-substrate seabed which had low to moderate ecological values, other habitats had low ecological values. Species of conservation interest recorded within the study area included three flora and ten fauna species (including bats, birds, hard corals and other fauna). The Project will not lead to any direct or indirect impacts to these species.

4.15.3 The Project would only affect small sizes of a few low value habitats including rocky shore, plantation and developed areas. The overall ecological impact is ranked as minor and the residual impact is considered acceptable with respect to EIAO-TM.

4.15.4 Besides good site practices, no other major mitigation measures for ecology is required. With the regular site inspection performed by the Environmental Team, no specific ecological monitoring programme is needed.

4.16 References

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