11.1 Legislation and Standards
11.1.1 The HKSAR ordinances and regulations relevant to fisheries impact assessment of this Project include the following:
(1) Environmental Impact Assessment Ordinance ("the EIAO", Cap. 499) and the associated EIAO-TM;
(2) Fisheries Protection Ordinance (Cap. 171) and its subsidiary legislation, the Fisheries Protection Regulations;
(3) Marine Fish Culture Ordinance (Cap. 353) and associated subsidiary legislation;
(4) Water Pollution Control Ordinance (Cap. 358) and its supporting regulations and statements; and
(5) Marine Parks Ordinance (Cap. 476).
11.2 Methodology for Baseline Establishment
11.2.1.1
The assessment area for Fisheries Impact
Assessment (FIA) is generally the same as the marine water quality impact
assessment area, includes the following three Water Control Zones (WCZ) within
HKSAR (see Drawing no. 209506/EIA/FSH/001) as
well as any areas likely to be impacted by the Project:
·
the
Junk Bay Water Control Zone,
·
the
Eastern Buffer Water Control Zone, and
·
the
Victoria Harbour Water Control Zone.
11.2.2 Sensitive Receivers
11.2.2.1
Key issues of the FIA required special
attention, as stipulated in the EIA Study Brief, include but not limited to the
following:
11.2.2.2
Tung Lung Chau Fish Culture Zone is about
4.2 km from the Project Site. There was no
other designated fish culture zone inside the Fisheries Assessment Area.
11.2.3 Collection and Review of Relevant Information
11.2.3.1
Information on the assessment area was
reviewed. A review of Government and
private sector reports, independent of Government published literature and
academic studies was undertaken to determine the existing conditions of
fisheries in the assessment area, and to identify practices, areas and species
of potential fisheries importance which may be affected by the Project. This review included but was not limited to
the following: Relevant literatures/publications on the ecological information
of the marine and fisheries study area (i.e. the Junk Bay, the eastern buffer
and the Victoria Harbour Water Control Zones) and nearby areas were reviewed.
Findings of relevant studies/surveys were reviewed, including:
·
Port
Survey 2006;
·
AFCD
annual reports;
·
Other
relevant reports from private sectors or Government.
·
Baseline
survey information conducted in EIA study- Further Development of Tseung Kwan O
Feasibility Study
·
Feasibility
Study on the Alternative Alignment for the Western Coast Road, Tseung Kwan O
·
Harbour
Area Treatment Scheme
·
Southeast
New Territories Landfill Extension
·
Kai
Tak Development
·
Consultancy
Study on Fisheries and Marine Ecological Criteria for Impact Assessment (CCPC
2001);
·
Fisheries
Resources and Fishing Operations in Hong Kong Waters (ERM 1998);
11.2.3.2
Port Survey is the most comprehensive
fisheries study conducted by AFCD every a few years. Different from the approach adopted in previous
Port Surveys in which Hong Kong waters were divided into “Fishing Areas” of
various sizes, a uniform grid was overlaid on Hong Kong’s waters for Port
Survey 2006 and the fisheries related information (e.g. production, vessel
number, catch value) was presented in several categories. In this FIA, the fisheries resources within
the assessment area were evaluated based upon the information from Port Survey.
11.2.3.3
AFCD’s annual reports provide the most
updated information on the development and trend in Hong Kong fisheries. The latest annual fisheries production is
also provided.
11.2.3.4
The validity of the information compiled
during the literature review has been assessed before it is adopted into the
present FIA study.
Data Gap Identification
11.2.3.5
Relevant studies and existing information have been
thoroughly reviewed, including EIA- Further Development of Tseung Kwan O
Feasibility Study
(EIA-111/2005). Fisheries resources of concern were identified based on
background information on the study areas, literature review results, and
consultation with relevant government authorities. Based on the review results,
it was found that there was no data gap and there was no need for field survey,
and a complete picture of the fisheries resources of the study area could be
produced.
11.3 Fisheries Baseline Conditions
11.3.1.1
The assessment area for fisheries impact
assessment is the same as the assessment area for marine water quality which
covers three WCZs. The Project Site is
located inside Junk Bay, within the transitional central zone of Hong Kong
marine waters, to the west of the oceanic eastern waters (Morton & Morton
1983).
11.3.1.2
While the fisheries assessment area covers
3 WCZs, the areas in the vicinity of the CBL alignment inside Junk Bay are
considered more relevant with the impact assessment. As the Project includes construction of the
marine section of CBL (in viaduct bridge form) across Junk Bay and its landing
section at the artificial seawall at the eastern shore of Junk Bay, both marine
waters and land areas are present in the vicinity of its alignment. But it should be noted that the construction
works for the CBL would only be conducted in marine waters and the seawalls.
11.3.2 Sites of Fisheries Importance
11.3.2.1
Fishing grounds cover most of the open
waters in Junk Bay, while a portion of Victoria Harbour WCZ and Eastern Buffer
WCZ is shipping fairways. The Project is
a marine base project involving bridge piers, and would cause loss of fishing
grounds in Junk Bay waters.
11.3.2.2
Besides the fishing grounds in Junk Bay
waters, the following sites of fisheries importance are located near the
Project Site within the boundary of the Fisheries Assessment Area and are shown
in Drawing no. 209506/EIA/FSH/001:
·
Tung
Lung Chau Fish Culture Zone
11.3.2.3
No other designated or recognized sites of
fisheries importance lie within the fisheries assessment area.
11.3.3 Capture Fisheries
11.3.3.1
The local fishing industry makes an
important contribution to Hong Kong marine fish supply. In 2011, it produced an estimated 170,720 tonnes of fisheries production valued at $2,358 million. The industry now consists of some
4,000 fishing
vessels and some 8,500 fishermen
working aboard and provides employment in ancillary sectors servicing the
fishing industry, such as fish wholesale and retail marketing, fuel and fishing
gear supply and ice manufacturing (information from AFCD website).
11.3.3.2
Detailed data on recent HKSAR capture
fisheries in the fisheries assessment area were taken from the results of Port
Survey 2006. Port Survey is the most
comprehensive fisheries study conducted by AFCD every a few years. The Port Survey consisted of an interview
programme. About 36% of the local
fishing fleet which accounted for all homeports (i.e. places at which local
fishing vessels are based, 38 ports) and vessel types (10 types, including
stern trawler, pair trawler, shrimp trawler, hang trawler, gill netter, long
liner, hang liner, purse seiner, sampan and miscellaneous craft) was
interviewed. During the interviews,
particulars (e.g. vessel length, type and its homeport) of the fishing vessels
were recorded and information about their fishing operations and fisheries
production in Hong Kong waters was collected.
11.3.3.3
In earlier Port Surveys, Hong Kong waters
were divided into fishing areas of various sizes and shapes, and these fishing
areas were further grouped into 12 sectors. In the latest Port Survey in 2006,
a uniform grid of 720ha cell size was overlaid on Hong Kong waters and the
fisheries related information (e.g. production, vessel number, catch value) was
presented in several categories. For
easy reference, in the present FIA study the rows and columns of the grid are
named by number and alphabetic order respectively, and a reference number is
assigned to each cell (Drawing no. 209506/EIA/FSH/002 to Drawing no. 209506/EIA/FSH/006).
11.3.3.4
Within HKSAR waters, the highest yields
for local fisheries were mainly derived from the eastern and southern coasts as
indicated in the distribution of overall fisheries production on adult fish
(see Drawing no. 209506/EIA/FSH/002),
while the marine waters inside the Fisheries Assessment Area for the present
EIA study were comparatively less productive.
11.3.3.5
Within the Fisheries Assessment Area,
there are some areas of higher production, inside Victoria Harbour and the
Eastern Buffer Water Control Zone. But all
these areas are all outside Junk Bay, far away from the Project and unlikely to
be influenced by the Project.
11.3.3.6
There are four areas of relatively higher
fish production in the Fisheries Assessment Area, including:
·
Grid
Cell N14
·
Grid
Cell O13
·
Grid
Cells Q15 and Q16
·
Grid
Cell Q18
11.3.3.7
Although the fisheries assessment area
covers the above mentioned extent, it is anticipated that the focal area for
capture fisheries issues would be the footprint of the Project itself (the
bridge alignment). The CBL bridge alignment
is located at Junk Bay. The majority of
it falls within Grid Cells P13 and Q13.
11.3.3.8
In Port Survey, grid cells are categorised
into one of the 6 classes, i.e. > 0-50 kg/ha; 50-100 kg/ha; 100-200 kg/ha;
200-400 kg/ha; 400-600 kg/ha; and 600-1000 kg/ha, in accordance with their
overall adult fish production. For CBL,
as reported in the Port Survey 2006 (see Drawing no. 209506/EIA/FSH/002 and
AFCD website), the catches from Grid Cells P13 and Q13 (the direct impact grid
cells) were ranked low to moderate in Hong Kong (100-200 kg/ha). These figures demonstrate that the direct
impact cells are of low to moderate importance to capture fishing operations in
Hong Kong.
11.3.3.9
The results of Port Survey 2006 indicated
that fry collection has become very limited and localized throughout Hong Kong
waters. Fish fry production was
concentrated in the eastern waters (Mirs Bay, Tolo Harbour and Channel, Port
Shelter and Po Toi), with a smaller contribution from the East Lamma Channel (Drawing no. 209506/EIA/FSH/003). No fish fry production was recorded in the
entire Fisheries Assessment Area.
11.3.3.10
The fishing operation in grid cells is
also categorized into 6 classes, i.e. > 0-10 vessels; 10-50 vessels; 50-100
vessels; 100-400 vessels; 400-700 vessels; and 700-1,000 vessels. The production is mainly contributed by
larger fishing vessels (> 15m in length).
There was no fishing vessels longer than 15m operated in Grid Cell P13
and Q13 (Drawing no. 209506/EIA/FSH/004). While the small vessels (<15m) were much
more common in these two grid cells (100-400 vessels, see Drawing no. 209506/EIA/FSH/005).
Therefore no production from vessels over 15m in these two cells (Drawing no. 209506/EIA/FSH/006). If only considering the vessels below 15m in
length, the production would be 100-200 kg/ha (Drawing no. 209506/EIA/FSH/007), same
as the overall production.
11.3.3.11
The values of fish production range from
HK$2,000 – 5,000 per ha in P13 and Q13 (Drawing no. 209506/EIA/FSH/008).
11.3.3.12
The marine waters inside the Fisheries
Assessment Area were not identified as important spawning grounds of fish and
shrimp during a fisheries study in Hong Kong (ERM 1998).
11.3.4 Culture Fisheries
11.3.4.1
As the Project is a marine base project
and no fishpond will be directly or indirectly affected by the Project, pond
fish culture is not an issue for the present FIA, and the culture fisheries
would only focus on mariculture. The
predominant type of mariculture in Hong Kong is marine fish culture which
involves rearing of marine fish from fry or fingerlings to marketable size in
cages suspended from floating rafts usually in sheltered coastal areas. Common species under culture include green
grouper, brown-spotted grouper, giant grouper, Russell's snapper, mangrove
snapper, red snapper, star snapper and pompano (Information from AFCD website).
11.3.4.2
Marine fish culture is protected and
regulated by the Marine Fish Culture Ordinance (Cap. 353), which requires all
marine fish culture activity to operate under licence in designated fish
culture zones. Currently, there are 26
fish culture zones occupying a total sea area of 209 ha with some 1,008 licensed operators. In 2011, the production from local marine fish
culture was 1,185 tonnes
(of value HK$94 million),
constituting 8% of the
local demand for live marine fish (Information from AFCD website).
11.3.4.3
Water quality within Marine FCZs is
regulated under the WPCO and its supporting regulations and statements. Within Fish Culture Subzones, the dissolved
oxygen level should not be less than 5 mg per litre for 90% of the sampling
occasions during the year; values should be calculated as water column average
(arithmetic mean of at least 3 measurements at 1 metre below surface, mid-depth
and 1 metre above seabed). In addition,
the concentration of dissolved oxygen should not be less than 2 mg per litre within
2 metres of the seabed for 90% of the sampling occasions during the year, and
the annual geometric mean of E. coli should not exceed 610/100 ml.
11.3.4.4
There are no Fish Culture Zones (FCZs)
within the footprint for the Project or in the vicinity. Of the 26 gazetted FCZs zones in Hong Kong,
only one occurs within the fisheries assessment area, i.e. Tung Lung Chau Fish
Culture Zone (Information from AFCD website).
Tung Lung Chau FCZ is about 4.2km to the southeast of the Project Site.
11.3.5 Fisheries Sensitive Receivers
11.3.5.1
Identified fisheries sensitive receivers
include the following:
·
Tung
Lung Chau Fish Culture Zone
11.3.5.2
This fisheries impact assessment aims at
providing sufficient and accurate data to allow complete and objective
prediction and evaluation of the potential fisheries impacts. Desk-top study has produced a complete
picture of the fisheries resources of the assessment area. The Port Survey and the consultancy study on
fisheries resources have provided information sufficient for fisheries impact
assessments in most EIA studies in Hong Kong SAR, and were considered adequate
for assessment of impacts of the present Project. No data gap in fisheries baseline was
identified in terms of fisheries assessment and therefore no field survey for
fisheries was needed.
11.4 Assessment Methodology
11.4.1 Identification of Sensitive Receivers
11.4.1.1
Sensitive receivers of impacts are defined
for this report as resources or sites of fisheries importance and potentially
affected directly or indirectly by the Project.
This implies that project-induced impacts are predicted to exceed the
range of fluctuation attributable to natural variation.
11.4.2 Impact Identification and Assessment
11.4.2.1
Impacts have been assessed in the absence
of mitigation. The construction and
operational phase impacts on capture fisheries and culture fisheries activities
have been assessed individually, then cumulatively, in combination with other
existing, committed and proposed developments.
11.4.2.2
The fisheries impact assessment
includes:
(1) identification of parameters (e.g. water quality parameters) and areas (e.g. breeding/spawning grounds and nursery grounds) that are important to fisheries and will be affected;
(2) identification and quantification of direct/indirect and on-site/off-site impacts to fisheries (e.g. loss of fishing grounds, reduction of catch/productivity, deterioration of water quality and pollution, if any, caused by surface run-off to mariculture activity);
(3) evaluation of impacts and recommendations for environmental mitigation measures with details on justification, scope description and programme, feasibility as well as manpower and financial implications including those related to subsequent management and maintenance requirements of the proposals; and
(4) review the need for monitoring during the construction and operation phases of the Project and, if necessary, propose a monitoring and audit programme.
11.4.2.3
As stipulated in the EIA Study Brief, the
FIA follows the criteria and guidelines for evaluating and assessing fisheries
impact as stated in Annexes 9 and 17 of the TM.
11.4.2.4
The assessment covers potential impact on
both capture and culture fisheries during the construction and operation of the
Project, and in combination with any cumulative impacts caused by projects
implemented simultaneous with or prior to the Project.
(1) description of the physical environmental background;
(2) description and quantification of existing capture fisheries, culture fisheries and oyster farming activities;
(3) description and quantification as far as possible of the existing fisheries resources (e.g. major fisheries products and stocks);
(4) identification of parameters (e.g. water quality parameters) and areas (e.g. breeding/spawning grounds and nursery grounds) that are important to fisheries and could be affected;
(5) identification and quantification of direct/indirect and on-site/off-site impacts to fisheries (e.g. loss of fishing grounds, reduction of catch/productivity, deterioration of water quality and pollution, if any, caused by surface run-off to mariculture sites);
(6) evaluation of impacts and recommendations for environmental mitigation measures with details of justification, description of scope and programme, feasibility as well as manpower and financial implications including those related to subsequent management and maintenance requirements of the proposals; and
(7)
review of the need for
monitoring during the construction and operation phases of the Project and, if
necessary, proposals for monitoring and audit programmes.
11.4.3 Criteria to Evaluate Impacts
11.4.3.1
The significance of fisheries impacts was
evaluated based primarily on the criteria set forth in Annex 9 of the EIAO-TM:
(1)
Nature of impact,
(2)
Size of affected area,
(3)
Loss of fisheries
resources/production,
(4)
Destruction and disturbance of
nursery and spawning grounds,
(5)
Impact on fishing activity, and
(6) Impact on aquaculture activity.
11.4.3.2
Impacts are generally ranked as
"minor", "moderate" or "severe", although in a
few cases a ranking of "insignificant" (less than "minor")
may be given. The ranking of a given
impact varies, based on the criteria listed above. Wherever possible, significance of impacts is
quantified to allow ready appreciation of relative significance. Quantification is straight forward for
certain types of impact, particularly fishing ground loss (usually measured in
hectares). Quantification of other types of impact such as those on fishing and
aquaculture activities requires the application of professional and value
judgment. Such judgment may not be
amenable to quantification.
11.4.3.3
In the present FIA, impacts on capture
fisheries was assessed by the extent of fishing ground loss during construction
and operational phases, and potential decline in productions due to loss of
fishing ground, interferences on fishing operations, and loss of fisheries
resources. Impacts on culture fisheries
were mainly assessed by the levels of changes of marine water quality presented
in the Water Quality Assessment for the present EIA study.
11.4.3.4
Efforts would also be made to identify
feasible and practicable mitigation measures required, which might be developed
to reduce the severity of any negative impacts identified. These measures would be described in terms of
scope, programme, feasibility and financial implications during the
construction and operation of the project.
11.4.3.5
Finally, the FIA would conclude whether
the mitigation measures could bring the negative impacts caused by the Project
and its components within acceptable bounds.
11.4.3.6
Besides adverse impacts, potential
beneficial influences brought by the Project, such as the additional hard
substrate surfaces brought by the artificial rubble-mount seawalls, bridge
piers and the associated rock armour protection which could provide similar
functions as artificial reefs, would also be considered in the assessment.
11.4.4 Recommendation of Mitigation Measures
11.4.4.1
Impacts are assessed in the absence of
mitigation. Efforts are made to identify
feasible and practicable mitigation measures required, that might be developed
to reduce the severity of any significant negative impacts to acceptable
levels. These measures would be
described in terms of their scope, programme, feasibility and financial
implications during the construction and operation of the project.
11.4.4.2
Finally, the assessment concludes whether
the mitigation measures envisaged could limit the negative impacts of the
project and its components to within acceptable bounds. The acceptability of the overall residual
impacts is determined.
11.5 Impact identification and evaluation
11.5.1 Construction Phase – Direct Impacts
Temporary and Permanent Fishing Ground Loss
11.5.1.1
The marine section of the CBL refers to
the viaduct from the TKO-LT Tunnel to the shoreline of eastern Junk Bay. This section of viaduct is completely on open
sea area and about 1.1km in length. No
terrestrial or intertidal habitat will be affected.
11.5.1.2
The marine section CBL will be a viaduct
supported by piers. Some physical loss
of marine areas will result from construction works at each location where
piers are installed to support the bridge deck. The CBL marine section would be
around 1.1km in length. There will be 12
pier sites, with the span ranging from 75m to 200m. At each pier site one
single pier would be constructed for a y-shape column, to support the bridge
deck.
11.5.1.3
At each pier site, piles would be bored
through the seabed sediment to reach a solid (rock) substrate. Atop a concrete pile cap will be constructed
(all pile caps would be beneath seabed surface to maintain the vessel traffic
and sea water flow) to support the bridge pier.
Each pier would be 10.3m x 18.4m in size (i.e. approximately 190 m2).
11.5.1.4
The size of the piers would be assumed a
seabed loss in this assessment. The
seabed area to be lost at each pier site approximately 190m2. The total seabed loss due to the project
footprint in the marine section of CBL would be 12piers x 190 m2 = 2,280m2,
i.e. 0.228ha or less than 0.3ha.
11.5.1.5
In addition to the loss of the seabed and
water column due to the project footprint (these losses will become permanent
fishing ground loss after completion of construction), works areas in each pier
site will cause additional temporary loss of seabed and water column habitat.
11.5.1.6
During the construction stage, at any
given time about two thirds of the 1.1km marine section will have a restricted
zone on 50m on either side to provide access for construction equipment and
labour, which does not allow vessels to enter.
These areas (9.6ha, 37m of the bridge breadth and 50m either side of the
bridge, along the 700m of viaduct) will be occupied as marine works areas.
Within the marine works area, no type of fisheries activity including capture
fisheries would be possible during the estimated 9 months bridge construction
phase. This would constitute a temporary loss of fishing grounds. The CBL marine section temporary fishing
ground loss would be 9.6ha. The 9.6ha of works area would constitute a
temporary loss of about 0.0058% of the 1,651km2 of Hong Kong total
marine waters (EPD 2005) which are mostly available for fishing. Given the
small percentage of area affected and the temporary nature, this represents an
insignificant impact to the capture fisheries in Hong Kong.
11.5.1.7
The marine section of CBL would have small
area of fishing ground loss (less than 0.3ha of permanent loss due to the
footprint, and 9.6ha for a 9 month construction period). The results from the Port Survey indicated
that the fisheries production inside Junk Bay is low to moderate
(100-200kg/ha), and thus the maximum loss from the less than 9.6ha would be
less than 1,920kg per year. The fishing ground loss from the marine section of
CBL is of small area and is scattered, thus the impact is considered as insignificant.
11.5.2 Construction Phase – Indirect Impacts
Marine Water Quality Deterioration
11.5.2.1
Large-scale dredging and filling works
associated with reclamation are the major sources of water quality impacts in
most marine projects. In the present
Project however, there will be no reclamation and thus significant water
quality impacts have been avoided. Other
activities/sources that may arise to potential water quality impacts during the
construction phase of the Project include:
(1)
Pier site excavation works; and
(2)
Construction site runoff.
11.5.2.2
During excavation, the seabed sediment
will be disturbed, and sediment plume might form and release into the nearby
waters. If the sediment plumes reach
fisheries sensitive receivers such as Tung Lung Chau Fish Culture Zone, there
might be sedimentation and increase of suspended solid in these receivers,
and/or reduction of DO due to the release of SS.
11.5.2.3
It is anticipated that the water quality
impacts due to excavation would be limited as the limited scale of excavation
works for the Project (only 12 pier sites). In addition, closed-grab excavator
and silt curtain for the excavation and filling would also be used. The measures would effectively prevent any
significant deterioration of water quality.
In the present EIA study, the water quality assessment considered both
CBL project and the TKO-LT Tunnel project, which are connecting with each
other and the construction programmes would therefore overlap. Thus, some of their marine works would be
performed simultaneously. Due to the
nature of the marine works (TKO-LT Tunnel would involve reclamation), the two worst
case scenarios selected in the modelling (see Section
8.5.3.6) both involve major marine works of
TKO-LT Tunnel (i.e. TKO-LT Tunnel reclamation only, as non-dredged method will be adopted in TKO-LT Tunnel). The water quality assessment considered
2 water quality sensitive receivers (WSRs) relevant with fisheries including
Tung Lung Chau Fish Culture Zone and the much faraway Po Toi O Fish Culture
Zone (it is outside the Fisheries Assessment Area), representing fish culture
operations. The modelling results showed
that during the construction phase, even the other WSRs closer to the Project Site (such as the
coral sites inside Junk Bay) would not experience
elevations of suspended solid in both wet and dry seasons even at the maximum
value (see Table 8-19 & 8-20). And thus none of these
fisheries relevant WSRs would be affected by suspended solid. During
the excavation activities for CBL project and the reclamation for TKO-LT Tunnel project, contaminants and nutrients may
be released to water column when sediment is contaminated and disturbed by marine construction works.
Therefore, elutriate tests were conducted (see Section 8.6.1.10 to Section 8.6.1.15). All the calculated concentrations of
heavy metals, metalloid TIN and UIA
comply with the proposed criteria. Thus adverse impacts due to release of contaminants on WSRs is not
anticipated. The water quality impact due to dredging
is ranked as Insignificant.
11.5.2.4
Potential impacts to aquatic habitats and
associated fisheries species from sedimentation due to surface runoff may also
arise during the construction phase.
Similar in the case of dredging, elevated suspended solids levels caused
by site runoff could increase the suspended solid load in the water bodies, and
could decrease dissolved oxygen levels.
This may affect the survivorship of fisheries species. The result could
be a temporary reduction in fisheries production. However as there was only limited land-based
construction works on eastern Junk Bay shore, the potential impact from runoff
to fisheries resources would be Insignificant.
11.5.2.5
There would also be wastewater from construction
activities, but there are requirements in site practice to ensure the proper
collection and treatment of the wastewater.
There is also an increased risk of small-scale oil or chemical
(construction works solvent) spills from vessels due to the increased number of
vessels working in the area. Because of the small volumes of such materials
involved, this risk is considered Insignificant.
Disturbance on Fishing Operation due to Marine Traffic
11.5.2.6
In the vicinity of the works areas,
fishing operation might be disturbed by the increased marine traffic of working
vessels for the Project. The disturbance impact however would be
temporary. As the majority of fishing
vessels operating in the vicinity are small-sized vessels (fishing vessels less
than 15m in length), these small vessels would have higher flexibility in their
operations and less sensitive to disturbance from marine traffic. Given the low fishing production in the
vicinity, this temporary impact would be insignificant. No mitigation is required.
11.5.3 Operation Phase – Indirect Impacts
Changes in Hydrological Regime
11.5.3.1
As the marine viaduct of CBL will be a
raised structure that will only slightly affect water flow, the bridge should
not have any significant effect on the hydrodynamic regime of Junk Bay in
general. The water quality of the area should not be significantly affected
once construction is completed. The
tidal flows simulations have been undertaken in order to obtain results for
condition if the CBL and TKO-LT Tunnel had been built (i.e. “with” scenario), and
if they were not implemented (i.e. “do-nothing” scenario) (see Section
8.7.1.2). By
comparing the results from these simulations, the possible hydrodynamic impacts
from CBL and TKO-LT Tunnel were assessed. The graphical
presentations for flow velocity vectors and accumulated flows show an
insignificant hydrodynamic impact with and without CBL and TKO-LTT. The water quality modelling results confirm that impact from the
changes in hydrological regime due to the presence of CBL is ranked as Insignificant.
Restrictions on Fishing Activities
11.5.3.2
During operational phase, as there will be
no marine restricted area for the CBL, fishing operations are basically not
restricted by the operation of the Project.
The spacing of the piers would be about 100m and would not restrict the
operations of small fishing vessels dominated in the area.
11.5.4 Cumulative impacts with other developments
TKO-LT Tunnel
11.5.4.1
The TKO-LT Tunnel will adjoin the CBL and would also require construction works inside Junk Bay. There would be potential on cumulative fishing ground
loss and cumulative water quality impacts from this concurrent project.
11.5.4.2
The CBL EIA study water quality assessment
has considered all concurrent projects including both CBL project and the
TKO-LT Tunnel project. Accordingly,
cumulative water quality impact from the TKO-LT Tunnel project has been
included.
11.5.4.3
TKO-LT Tunnel project is a
separate DP under the EIAO and hence a separate EIA Study would be conducted by
the respective project proponent to address all the impacts (including cumulative impacts) during both
the construction and operational phases.
11.5.4.4
In accordance with the TKO-LT
Tunnel EIA report, direct fisheries impacts during the construction phase of
TKO-LT Tunnel include permanent loss of 3.6 ha of fishing ground and temporary
loss of 19ha of fishing ground. There
will be a small area of fishing ground loss due to CBL (less than 0.3 ha of
permanent loss due to the footprint, and 9.6 ha of temporary loss during a 9
month construction period) and the cumulative fishing ground loss impacts
caused both by CBL and TKO-LT Tunnel should be acceptable.
Other concurrent projects
11.5.4.5
Marine works due to Shatin Central Link, CLP Offshore
Windfarm, Cruise Terminal, Trunk
Road T2 and Submarine
Gas Pipeline will be concurrent with the CBL and TKO-LT Tunnel projects.
11.5.4.6
According to the EIA Report for Submarine
Gas Pipeline (EIA-182/2010) (Tables 3.20 and 3.21, Appendix B5), the plume
envelope of cumulative impact due to Cruise Terminal, Trunk Road T2 and
Submarine Gas Pipeline Relocation will not reach these WSRs. Therefore, that
exceedance would be likely due to the concurrent marine works of Offshore
Windfarm only. The cumulative suspended solid has been taken into account the Windfarm project (see S8.6.1.3) and the results are presented
in Tables 8-19 to 8-20. A full compliance of
SS levels at identified WSRs was predicted due to CBL and TKO-LT Tunnel project
and with cumulative projects.
11.6 Mitigations of Adverse Impacts
11.6.1.1
The span of the piers for CBL ranges from
75m to 200m. This span is larger than the normal 50m span for bridge
structure. With the larger span, a
smaller number of piers are required and thus the number of construction works would be reduced. Associated impacts on marine habitat loss and
marine water quality would therefore be minimised.
11.6.2 Mitigations
Water quality
11.6.2.1
No reclamation would be needed for
CBL. The water quality impact would
range only from insignificant to minor.
Therefore the site practices and regular site runoff control measures
would be sufficient to protect water quality.
11.6.2.2
Good site practices: it is recommended that the integrity
and effectiveness of all silt curtains should be regularly inspected. Effluent monitoring should be incorporated to
make sure that the discharged effluent from construction sites meets the
relevant effluent discharge guidelines.
11.6.2.3
Site runoff control: for works
on land, standard site runoff control measures should be established and strictly enforced to
ensure that any discharge
of contaminated or silt-laden runoff into marine waters
is minimised.
11.7.1.1
The residual environmental impacts refer
to the net environmental impacts after the implementation of mitigation
measures, taking into account the background environmental conditions and the
impacts from existing, committed and planned projects.
11.7.1.2
In some instance, measures have been
incorporated into the design and/or construction methods (e.g. larger bridge spans to reduce the number of pier foundations) to provide an
additional degree of confidence that any residual impact would not be expected to pose long term environmental implications.
11.7.1.3
The loss of less than 0.3ha of fishing ground loss of low to
moderate production is considered
acceptable.
11.7.1.4
With good site practices and site runoff
control properly implemented there would be no significant residual impacts
on the fisheries resources and fishing operations inside Junk Bay due to water
quality because the majority of marine habitats will remain intact.
11.8.1.1
The water quality programme could also
serve the purposes to protect the marine communities inside Junk Bay. No
specific fisheries monitoring programme is needed.
11.9.1.1
There is no fish culture zone or spawning
and nursery grounds for fisheries species inside Junk Bay, or inside or close
to the CBL alignment.
11.9.1.2
The CBL would cause only limited (<
1ha) loss of fishing ground of low to moderate production. These habitat loss
impacts ranked as insignificant to minor due to the small size and low
ecological value of the habitats.
11.9.1.3
Only limited marine water quality impacts
are anticipated as only 12 pier sites are needed for the project and no
reclamation will be performed. Other impacts are also minor or insignificant.
11.9.1.4
The residual impacts, fishing ground loss,
are considered acceptable. No specific fisheries monitoring programme is
needed.
11.9.1.5
It is therefore
concluded that the limited fisheries impacts identified by assessment according to Annex 17 of the EIAO-TM would
comply with criteria provided by
Annex 9.
AFCD 2006. Port Survey 2006.
AFCD 2003. Artificial Reefs and
Reef Fish in Hong Kong.
Arup 2002. Shenzhen Western
Corridor – Investigation
CCPC 2001. Consultancy Study on
Fisheries and Marine Ecological Criteria for Impact Assessment.
EPD 2005. 20 years of marine
water quality monitoring in Hong Kong.
ERM 1998. Fisheries Resources and
Fishing Operations in Hong Kong Waters.
ERM 2000. Study on Sustainable
Development for the 21st Century: Environmental Baseline Survey on Terrestrial
Habitat Mapping and Ranking Based on Conservation Value. Final Report to the
Planning Department.
ERM 2005. New Contaminated Mud
Marine Disposal Facility at Airport East / East Sha Chau Area.
Morton, R & B. Morton 1983.
Seashore Ecology of Hong Kong. Hong Kong University Press.