This Section
summarises the environmental outcomes associated with
the construction and operation of the Project.
14.2.1
Construction Phase
Construction dust generating from the soil excavation, embankment construction,
dry weather flow interception works, landscaping works, patrol road and boundary
fence re-provisioning and
odour from dredging and handling of river sediment are the key air quality
concerns during construction phase.
With the implementation of the recommended dust
control measures and good construction site practices, the construction of the
Project will not cause adverse dust and air quality impacts. Dust monitoring during the construction
stage is recommended to ensure compliance with the Air Quality Objectives.
The measured acid volatile sulphide (AVS) concentrations in the sediment
samples of the Project Site were well below that for the remediated sediments,
which are considered to have minimum odour impact to the surrounding
environment. The dredged sediment
will be stored in enclosed tanks and will be delivered off-site for disposal at
regular intervals. Therefore,
potential odour impact due to dredging and handling of river sediment will be
minimal.
The frequency and scale of maintenance dredging
required along the river channel and the flood retardation pond is anticipated
to be very small compared with the dredging works during the capital works. Besides, the dry weather flow
interception works to be carried out under this Project will convey the
untreated sewage from Shenzhen side (which are currently discharging to the
Owing to the close proximity of some of the NSRs to the works areas of the Project, mitigation measures
are required to be implemented to mitigate the construction noise impacts. Practicable mitigation measures,
including good construction site practices, use of quiet PME, movable noise
barriers and scheduling of PME/construction activities, are recommended. With the implementation of mitigation
measures, the mitigated construction noise l
The
potential sources of water quality impacts associated with the construction and
operation of the Project have been identified and the potential impacts were
evaluated using proven mathematical models. The modelling has assessed a number of
scenarios (including a number of worse case scenarios) for pollutants
(including SS, heavy metal, nutrients and micro-organic pollutants) releases
from the construction activities, and maintenance dredging and the change of
the hydrodynamic conditions of the river during the operation of the
Project.
14.4.1
Construction Phase
Potential
impacts arising from the proposed construction works are predicted to be
largely confined to the specific works areas. With proper implementation of the
recommended mitigation measures, sediment dispersion is not expected to cause
adverse water quality impacts at the identified water sensitive receivers.
With
the implementation of the recommendation mitigation measures, no residual water
quality impacts are envisaged due to the construction of the Project. Nevertheless, a monitoring programme is recommended during
construction phase to verify the predictions of the EIA and ensure compliance
with the assessment criteria.
14.4.2
Operation Phase
During the operation phase, changes to hydrodynamic
regime within the Project Site are predicted to be beneficial and no adverse
impacts are anticipated. Adverse
water quality impacts are not expected at any identified water sensitive
receivers due to the operation of the Project. The scale and volume of the maintenance
dredging activity will be significantly smaller than that of the capital
construction work. Adverse water
quality impact is not expected.
With the
implementation of the recommended mitigation measures, no residual water
quality impacts are envisaged due to the operation of the Project.
Cumulative
water quality impacts associated with operation of the LT/HYW BCP have been
considered, no adverse impact is anticipated.
The ecological resources recorded within the Study Area
included twelve habitats (woodland [including fung shui woodland], plantation, shrubby grassland, low-lying
grassland, marshy low-lying grassland, abandoned agricultural land, cultivated
land (dry), wet active agricultural land, stream / river, channel, pond and
developed area) of which only two were not found in the Project Site (shrubby
grassland and pond). Low-lying
grassland, cultivated land (dry), wet active agricultural land, channel, pond
and developed area (including road / path) were considered as having low
ecological value, secondary woodland and the stream / river other than the
Shenzhen River as having moderate ecological value, fung
shui woodland as having high ecological value and the
remainder (plantation, shrubby grassland, abandoned agricultural land and
Shenzhen River) as having low to moderate ecological value. One small section of the
A total of 38 wildlife species of conservation
interest were recorded within the Study Area during the surveys, including six
mammal species (Small Indian Civet, East Asian / Malayan Porcupine, Leopard Cat
and three unidentified bat species), twenty six bird species (Crested
Serpent Eagle, Besra, Black Kite, Common Buzzard,
Peregrine Falcon, Greater Spotted Eagle, Bonelli's
Eagle, Savanna Nightjar, Emerald Dove, Greater Coucal, Lesser
Coucal, Asian Barred Owlet / Cuckoo Owl, Japanese Sparrowhawk,
Crested Goshawk and Greater Painted Snipe, Chinese Pond Heron, Black-crowned
Night Heron, Grey Heron, Great Egret, Intermediate Egret, Little Egret, Cattle
Egret, Little Green Heron, Common Teal, White-breasted Waterhen
and Yellow-breasted Bunting), one herpetofauna
species (Chinese Bullfrog) and one rare butterfly species Courtesan. Only thirteen of these species were
recorded in the Project Site during the surveys, twelve of them being highly
mobile birds (Greater Coucal, Common Buzzard,
Peregrine Falcon, Black Kite, Chinese Pond Heron, Black-crowned Night Heron,
Grey Heron, Great Egret, Intermediate Egret, Little Egret, Common Teal and
White-breasted Waterhen) and the other being the
Courtesan butterfly which despite not being as mobile, has an abundance of
similar habitat in the immediate vicinity.
Hence, it is anticipated that the impact to these species is low.
The Project will cause some permanent habitat
loss. The
A bird monitoring programme will be undertaken to
monitor the effectiveness of the reprovisioned/reinstated
habitats during the operation of the Project. Monitoring of bird abundance and
occurrence will be undertaken for one year after the establishment of the
landscape plantings of the Project.
A total of one active fishpond and three abandoned
fishponds were identified within the 500 m Study Area of the Project Site. No direct or indirect negative impacts
on the pond fish culture resources are anticipated during the construction or
operation of the Project.
14.7.1
Construction Phase
During the construction phase, the main activities,
which will result in the generation of waste, include dredging of river sediment,
soil excavation, embankment construction, sewage diversion works, landscaping
works, and patrol road and boundary fence re-provisioning. The waste types associated with these
activities include dredged river sediment, C&D materials, chemical waste,
sewage and general refuse.
It is estimated that the gross total
C&D materials generated from the Advanced Works within the HKSAR will be
about 18,750 m3. About
15,000 m3 will be inert but not suitable fore ruse on site. These materials will be disposed of in a
public fill reception facility in HKSAR.
A small quantity of about 3,750 m3 of construction waste
(non-inert C&D material) will be disposed of at the NENT Landfill.
It is estimated that a gross total
excavated materials generated from the river modification and associated works
will be about 690,200m3, comprising 95,000 m3 of river
sediment, 586,000 m3 of inert C&D material and 9,200 m3
of non-inert C&D material (construction waste). For the 95,000 m3 river
sediment, about 27,000 m3 with all contaminants levels not exceeding
the LCEL (Category L) will be disposed of at Huangmao
Dao in Zhuhai and the remaining sediments (with
Categories M and H) of 68,000 m3 will be disposed of at the Type 1
(dedicated) and Type 2 marine disposal facilities as appropriate within the
HKSAR, to be determined by the MFC of the CEDD. Of the 595,200 m3 C&D
materials, about 586,000 m3 are inert in nature. About 114,800 m3 of these
inert C&D materials will be reused on site for backfilling or embankment
construction and the surplus inert C&D materials of about 471,200 m3
will be disposed of at Huangmao Dao (黃茅島) in Zhuhai. About 9,200
m3 of construction
waste (non-inert materials) will be generated and require disposed of at
landfills in Shenzhen.
For the
disposal of C&D material, the Shenzhen River Regulation Office and the DSD
shall obtain confirmation from the Public Fill Committee (PFC) in
For the
disposal of dredged sediment, The Shenzhen River Regulation Office and the DSD
will obtain confirmation from the MFC in
During the peak construction period, approximately
878.5 kg per day of general refuse will be generated (195 kg from Advanced
Works and 682.5 kg from River Modification and Associated Works). General refuse will be disposed of at
landfills in Shenzhen or at NENT Landfill in the HKSAR (for the Advanced
Works). Provided that the general
refuse are properly collected and disposed of at regular intervals, no adverse
environmental impacts are envisaged.
Chemical waste will be handled in accordance with the
Code of Practice on the Packaging,
Handling and Storage of Chemical Wastes. For the Advanced Works, the chemical
waste will be collected by a licensed chemical waste collector to the Chemical
Waste Treatment Facility for disposal.
For the river modification and the associated works, the chemical waste
will be collected and disposed of at licensed hazardous waste treatment
facilities in Shenzhen.
With the implementation of general good construction
site practices, it is not anticipated that the construction of the Project will
cause adverse environmental impacts due to handling, transportation and
disposal of the wastes.
14.7.2
Operation Phase
Maintenance dredging will be carried out along the river
channel and the flood retardation pond.
The scale of the dredging work is anticipated to be small and hence the
volume of sediment is expected to be less than that of the dredging works
during the construction phase. The
disposal and handling of the dredged materials will follow the requirement in
the ETWB TC(W) No. 34/2002.
With the implementation of general good construction
site practices, it is not anticipated that the operation of the Project will cause
adverse environmental impacts due to handling, transportation and disposal of
the wastes
In the vicinity of the Project area, a few potential
commercial and industrial developments were identified during the site
surveys. These included abandoned
poultry/livestock farms, a plant nursery, a non-operating industrial facility
(a bean curd stick production plant) with an air emission stack, a police
station with a dangerous goods store, and a pumping station for the
As the result of the above, no potential impact from
the contaminated soil is anticipated.
Literature review and field
surveys identified no
Nevertheless, the identified
built heritage features will not be directly or indirectly impacted by the
proposed development as they are located far from the Project Site. No mitigation measure or monitoring will
be required during the construction and operation phases of the Project.
The archaeological survey
identified only the secondary archaeological deposits at Chuk
Yuen and Pak Fu Shan sections of the
Project. The chance of finding in situ archaeological deposits is very
low. Thus, no impact on significant
archaeological resources is anticipated and no archaeological monitoring is required. Other sections have been identified with
no archaeological potential where no impact is anticipated, thus no
archaeological monitoring is required.
Pursuant
to the Antiquities and Monuments
Ordinance, the project proponent should inform the AMO immediately in case
of discovery of antiquities or supposed antiquities in the course of soil
excavation works in construction stage.
However, it should be noted that the archaeological
impact assessment covered only the works area assigned as at the date of this
report. If the works boundary
changes in later stage to cover additional area not covered in the EIA, the
need for further archaeological survey and subsequent impact assessment should
be reviewed and AMO should be consulted.
14.10
Landscape and
Visual Impact
With
regard to LIA, a total of 18 LRs and four LCAs have been identified in the Study Area. There will be moderate or slight residual landscape
impacts on eight LCAs/LRs as detailed below
The significance of residual, adverse landscape
impacts on LCA 4 (
The significance of residual, adverse landscape
impacts on LCA 1 (Settled Agricultural Lowland Landscape), LR4 (
Upon mitigation, at day 1 of operation, the
significance of residual, adverse impact on one LCA and two LRs
is moderate (LCA4 (
The Project has insignificant residual landscape
impacts on all other insignificant.
With regard to VIA, five VSRs
representing two categories (residents and travellers) have been identified in
the visual envelope to represent key visually sensitive receivers in the
area. Photomontages have been
constructed at three VPs in three of these VSRs to
help illustrate the visual impact of the Project. A further two planned VSRs have been identified: the future residents of the
re-sited
At
construction phase, the unmitigated impacts identified are significant for three VSRs (residents of
Ta Kwu Ling Village, Residents of Kaw Liu Village and
Residents of the current Chuk Yuen Village), moderate for two VSRs
(Travellers along Lin Ma Hang Road, and Residents of Tsung
Yuen Ha), slight for one VSR (future
residents of the re-sited Chuk Yuen Village) and not applicable for one planned VSR
(Travellers through the LT/HYW BCP).
After mitigation the significance of all the visual impacts will have
been reduced, with the exception of the residents of the re-sited Chuk Yuen village who may still suffer slight visual
impacts. Therefore residual impact
at construction is moderate for
three VSRs (residents of Ta Kwu
Ling Village, Residents of Kaw Liu Village and Residents of the current
At
operation phase, the unmitigated impacts identified are moderate for three VSRs (residents of Ta Kwu Ling Village, Residents of Kaw Liu Village and
Residents of the current Chuk Yuen Village if this
village is still in existence at this location) and slight for four VSRs (Travellers along
Lin Ma Hang Road, Residents of Tsung Yuen Ha, future
Residents of the re-sited Chuk Yuen Village and
future Travellers through LT/HYW BCP).
There are no significant impacts for the operation phase, even without
mitigation.
Following
the implementation of the proposed visual mitigation measures, at day 1 of
operation, the mitigated impacts are slight
for four VSRs (Residents of Ta Kwu
Ling Village, Residents of Kaw Liu Village, Travellers along Lin Ma Hang Road
and Residents of the current Chuk Yuen Village if the
village is still in existence); and insignificant
for the two VSRs (Residents of Tsung
Yuen Ha and future Residents of the re-sited Chuk
Yuen Village). The LT/HYW BCP will
not be operational at this point, so the visual impact on Travellers through
the LT/HYW BCP is not applicable.
At year 10 of operation, when planted and natural vegetation has had
time to mature all residual impacts are insignificant,
including for Travellers through the LT/HYW BCP which will be operational by
this time.
According to Annex 10 of the EIAO-TM, the landscape and visual
impacts of this Project are considered acceptable with mitigation.
14.11
EM&A
Requirement
Monitoring of dust, noise and water quality has been
recommended at designated sensitive receivers during the River Modification and
Associated Works. Environmental
site audit shall be conducted throughout the construction phase for both River
Modification Works and Associated Works and Advanced Works to ensure that the
proposed mitigation measures are implemented, and completed landscape works
will be monitored during a one-year establishment period.
A bird monitoring programme will be undertaken to
monitor the effectiveness of the reprovisioned/reinstated
habitats during the operation of the Project. Monitoring of bird abundance and
occurrence will be undertaken for one year after the establishment of the
landscape plantings of the Project.
The environmental impact assessment has concluded
that no unacceptable environmental impacts are envisaged as a result of the
construction and operation of the Project, provided that the recommended
mitigation measures are implemented.
14.13
Key Environmental
Outcomes
14.13.1
Population and Environmentally Sensitive
Areas Protected
The Project improves the flood
prevention performance of the
The EIA has concluded there are no residual impacts
as a result of the construction and operation of the Project. With the implementation of the
recommended mitigation measures, the population in the Ta Kwu
Ling area are effectively protected from environmental nuisance.
There are no environmentally sensitive areas in the
vicinity of the Project Site. The
water quality impact assessment concluded that there will be no adverse impact
to the Mai Po Inner Deep Bay Ramsar Site and Mai Po Marshes and Inner Deep Bay SSSI which are located more than 10 km
downstream of the Project Site.
14.13.2
Environmentally Friendly Design Options
and Features
Environmentally Friendly Design Option
This preferred design option maintains the existing profile of the
concerned section of the
Environmental Friendly Features
The environmental friendly design features of the
Project include:
·
Keep
existing meandering profile so as to maintain the existing landscape as far as
possible;
·
Keep
meanders at bending location to act as a floodplain; and
·
Provide
wetland habitat in the flood retardation pond.
14.13.3
Key Environmental Problems Avoided
The design principle adopted for the Project minimised
the alteration to the river and thus minimising the environmental impacts to
the environmental sensitive receivers.
14.13.4
Environmental Protection Measures and
Precautionary Measures
Mitigation measures and good site practices have been
recommended through the impact assessment to minimise the potential impacts to
the environment. The Project will
unavoidably impact a small area of woodland/plantation habitat. Compensation of woodland plantation with
native species within the Project Site has been recommended. Proper ecological design will be adopted
for the landscape works along the river banks and flood retardation pond. With the adoption of
ecological design, the
landscaping works at the river banks of the concerned channelised section of the