1.1 General
1.1.1 On 18 April 2001, Highways Department (HyD) of the Government of the Hong Kong Special Administrative Region appointed Mouchel Asia Ltd, under Agreement No. CE 13/2001, to provide professional services in respect of the Improvement to Tung Chung Road between Lung Tseng Tau and Cheung Sha Investigation and Preliminary Design Assignment. The location of the “Broad Corridor for Alignment Options” for the Project as given in the Assignment Brief is shown in Figure 1.1.
1.1.2 The purpose of the Project is to improve the existing sub-standard Tung Chung Road, and thereby provide an improved roadway for connecting north and south Lantau. The improved road will comprise a two-lane two-way rural road, with gradients as steep as 15% and no climbing lane to minimise the environmental impacts of the improved road. The improved road will be operated as a closed road in a similar manner to the existing road to prevent vehicles from the rest of Hong Kong, without Lantau Closed Road (LCR) permits, from entering South Lantau. Subject to further analysis, the current Tung Chung Road Prohibited Zone (TCRPZ) permit system might also require retention with appropriate modification to manage traffic on the improved road and tightly control its growth.
1.1.3
The Project is a designated project
under Section A.1 of Schedule 2 of the Environmental Impact Assessment
Ordinance (EIAO). As such the statutory procedures under the EIAO need to be
followed and an environmental permit is required prior to the commencement of
construction. Thus, as part of this assignment, an Environmental Impact
Assessment (EIA) has been undertaken.
1.2 Justification for the Project
1.2.1 The existing Tung Chung Road is grossly sub-standard, carries a significant proportion of buses and coaches and is experiencing an increasing number of traffic accidents. Although Government has introduced operational controls in an attempt to maintain safe traffic conditions on the existing road, the number of traffic accidents is already considered high. As such, the improved road is now required urgently to rectify this undesirable situation. Thus, the Project is considered essential. The Project is also recommended under the “South West New Territories Development Strategy Review – Recommended Development Strategy”. Further details on the justification for the Project are provided in Appendix A.
1.2.2 In addition to the above, the South Lantau residents, through the auspices of the Islands District Council, have requested that the improved road be constructed as a matter of urgency. Based upon the wishes of the local residents, alternative modes of transport, such as a cable car or direct ferry services between North and South Lantau, would not suffice. However, public transport, in the form of franchised buses and Lantau taxis will be allowed to use the improved road.
1.3 Selection of the Recommended Preferred Solution for the Project
Widening of Tung Chung Road Feasibility Study (Agreement No. CE 26/96)
1.3.1 In November 1996, HyD appointed Consultants to carry out a detailed feasibility study for the improvement of the existing Tung Chung Road to a rural single 2-lane carriageway with an additional climbing lane (ie total 3-lanes) over the uphill sections. The study initially considered an on-line widening scheme, but found that after widening, the road would still be substandard, with about 4 km length exceeding 10% gradient, of which about 2.5 km would exceed 15% gradient and about 0.5 km would be up to about 20% gradient. Such long and steep gradients on a new road were considered unsafe, and therefore the on-line scheme was deemed to be unacceptable. Furthermore, the scheme would affect about 10 ha of country park.
1.3.2 In order to improve the gradients to current standards, the study subsequently considered an off-line improvement scheme comprising a meandering alignment across the Tung Chung and Cheung Sha valleys. However, although the gradients of this new scheme complied with current standards, the meandering alignment included a series of sharp bends, and although each bend complied with the current standards for the "absolute minimum radius (R1)" of 44 m for a 50 kph design speed, the repeated use of such tight bends, especially on what would still be a relatively steep road, was considered hazardous to traffic. The study also found that the meandering alignment would affect about 20 ha of country park. Because of its poor geometry and impact on the Country Park, the off-line scheme (R1: 44 m) was also considered unacceptable.
1.3.3 Further study was then undertaken to improve the tight bends, and the Consultants briefly studied a further off-line scheme based on the standard "normal minimum radius (R3)" of 88 m for a 50 kph design speed. Radii of not less than 88 m were considered the minimum acceptable given the relatively steep gradients along the road. However, the Consultants found that the off‑line scheme (R3: 88 m) would meander even further than the off-line scheme (R1: 44 m), and as such would have a greater impact on the Country Park, with about 27 ha of country park being affected.
1.3.4 Both the on-line and off-line schemes (R1: 44 m) were presented to the Country Parks Committee (CPC) of the Country and Marine Parks Board on 20 March 1997. The CPC expressed their concern about the impacts that the works would have on the Country Park, and advised that other alternative routes should be considered for a north-south road link. In view of the engineering and environmental problems of the on-line and off-line schemes, the Steering Group for the study decided not to proceed further with the schemes.
Review of Other Alternative Routes by HyD
1.3.5 Following the decision not to proceed with the schemes considered in the “Widening of Tung Chung Road Feasibility Study”, a review of other alternative routes for a north-south road link was carried out by Government, which identified a possible route between Tai Ho Wan and Mui Wo.
Lantau North-South Road Link between Tai Ho Wan and Mui Wo Preliminary Project Feasibility Study (Supplementary Agreement to Agreement No. CE 26/96)
1.3.6 In August 1997, HyD appointed Consultants to carry out a preliminary project feasibility study (PPFS) for a proposed north-south road link between Tai Ho Wan and Mui Wo to provide a safe alternative road to the sub-standard Tung Chung Road. The PPFS recommended an overland route which climbed over the natural saddle in the ridge of Lantau Island between Tai Ho Wan and Mui Wo, passed along the hillside to the west of Mui Wo, and connected to South Lantau Road through the Nam Shan area.
1.3.7 The proposed scheme was presented to the CPC at its meeting on 13 January 1998. The CPC requested that further alignment options, including tunnel options, be considered in the subsequent detailed study in order to reduce the impacts on the existing and proposed country parks and recreation facilities, woodland and other habitats.
Lantau North-South Road Link between Tai Ho Wan and Mui Wo Investigation Assignment (Agreement No. CE 31/98)
1.3.8 In July 1998, HyD appointed Consultants to carry out a detailed feasibility study for the proposed road link. The study brief required the Consultants to study all possible alignment options, including tunnel options, within a broad corridor between Tai Ho Wan and Mui Wo, to recommend a preferred alignment option, and to carry out the preliminary design and detailed EIA on the recommended preferred alignment option.
1.3.9 After studying a number of possible alignment options, the Consultants recommended a similar alignment to that recommended in the PPFS, except that instead of connecting to South Lantau Road in Nam Shan, the new road connected to the end of Ngan Kwong Wan Road in Mui Wo. The recommended alignment was endorsed by the Steering Group for the study on 2 March 1999.
1.3.10 The EIA for the endorsed alignment was submitted under the EIAO on 2 November 1999, but the Director of Environmental Protection (DEP) advised on 22 December 1999 that it did not meet the requirements of the EIA study brief and the Technical Memorandum (TM) on EIA Process. The Consultants subsequently revised the EIA, which was resubmitted under the EIAO on 15 September 2000. The DEP advised on 13 November 2000 that the revised EIA also did not meet the requirements of the EIA study brief and the TM. As such, HyD decided not to proceed further with this scheme.
Further Review of Other Alternative Routes by HyD
1.3.11 Following the decision not to proceed with alignment considered in the “Lantau North-South Road Link between Tai Ho Wan and Mui Wo Investigation Assignment”, HyD re‑examined the topography of Lantau, and found that the only other feasible overland corridor was between Siu Ho Wan and Mui Wo, as shown in Figure 1.2 (Option No. 7). However, HyD found that any alignment along this corridor would entail substantial problems, including:
· affecting a small part of Tai Ho Bay, which would likely be unacceptable to EPD;
· encroaching on the boundary of the Discovery Bay development, including the golf course, which would likely generate strong objections from the residents; and
· extensive earthwork cuttings and fill slopes along the route, due to the difficult topography of this particular corridor.
1.3.12 To overcome the topographical constraints, HyD also identified several possible tunnel options, as shown in Figure 1.2 (Option Nos. 1 to 6). However, all these options comprised tunnels of about 4 km in length. The safety requirements for such a long tunnel would require a twin-tube tunnel, each with a width of two lanes, to cater for emergency situations. This would result in a new road with a capacity much higher than the demand arising from the recreational orientated development in South Lantau envisaged under the “South West New Territories Development Strategy Review – Recommended Development Strategy”. As such, there would likely be pressure to open South Lantau to more intensive development eventually, which would be contrary to the recommended development strategy. Moreover, a twin-tube tunnel would cost about $5 billion to construct, as opposed to about $1.0 billion for an overland route.
1.3.13 Based on the above findings, HyD re-examined the possibility of improving the existing Tung Chung Road. HyD found that by relaxing the gradient requirements by adopting a maximum gradient of 15% (as opposed to the normal standard of 10%) and by not providing a climbing lane despite the steep gradients, the impacts on the Country Park could be reduced.
Improvement to Tung Chung Road between Lung Tseng Tau and Cheung Sha Investigation and Preliminary Design Assignment (Agreement No. CE 13/2001)
1.3.14 As stated at the beginning of this section of the report, in April 2001, HyD appointed Mouchel Asia Ltd to carry out a detailed feasibility study for the for the improvement of the existing Tung Chung Road to a rural single 2-lane carriageway, with gradients as steep as 15% and no climbing lane to minimise the environmental impacts of the improved road.
1.3.15 The development and assessment of the various alignment options for the proposed road improvement, undertaken during this Assignment, are described in Appendix B (Alignment Options Assessment), and the selected preferred alignment option is described in Section 2 of the report (Project Description). The main advantages of preferred option, compared to the other alignment options, are as follows:
· shortest overland route between Tung Chung and South Lantau Road, with gentle bends and no tight loop-bends;
· least amount of bridgeworks, earthworks and retaining walls, resulting in least amount of “muck shifting” and surplus excavated material;
· least potential to impact Tung Chung Stream and Cheung Sha Stream (alignment avoids Cheung Sha Stream as far as possible);
· least ecological impacts;
· least landscape and visual impacts for overland route;
· least impacts on the Country Park for overland route; and
· least construction cost and shortest construction programme.
1.4 Consequential Development Arising from the Project
General
1.4.1 Various green groups have expressed concern about consequential development arising from the Project. These fears may be largely allayed, since the purpose of the Project is simply to improve the existing road, and thus any consequential development should be relatively small. The improved road will only comprise a two-lane two-way rural road, with gradients as steep as 15% and no climbing lane to minimise the environmental impacts of the improved road, as discussed above. As such, the improved road will only have a total two-way capacity of about 1,450 pcu/hour (ie, about 1,000 vehicles/hour). Furthermore, the improved road will remain a closed road to prevent vehicles from the rest of Hong Kong, without LCR permits, from entering South Lantau. Subject to further analysis, the current TCRPZ permit system might also require retention with appropriate modification to manage traffic on the improved road and tightly control its growth.
Existing Land Use Controls
1.4.2 The plan nos. of the current outline zoning plans (OZPs) for South Lantau Coast and Mui Wo Fringe are S/SLC/11 and S/I-MWF/3 respectively. The existing population figures for South Lantau Coast and Mui Wo Fringe are 4,900 and 1,900 respectively. According to the explanatory statement of the plans, the population upon full development for South Lantau Coast and Mui Wo Fringe are 14,000 (including 4,000 prisoners) and 3,400 respectively. As for Mui Wo, the existing population and population upon full development are about 5,000 and 10,000 respectively. Based on the OZPs, the total future residential provision (excluding Small House provision) is shown in Table 1.1 below.
Table 1.1 Total Future Residential Provision along South Lantau Coast and Mui Wo
|
Area |
No. of Flats |
||||
|
CR |
R3 |
R4 |
R(D) |
Total |
|
|
Mui
Wo |
58 |
18 |
275 |
650 |
1,001 |
|
Chi
Ma Wan |
|
|
310 |
|
310 |
|
Cheung
Sha |
|
|
226 |
|
226 |
|
Pui
O |
|
|
|
|
0 |
|
Shui
Hau |
|
|
242 |
|
242 |
|
Cheung
Sha West |
|
|
74 |
|
74 |
|
Total: |
58 |
18 |
1,127 |
650 |
1,853 |
1.4.3 According to the current South Lantau Coast OZP, the areas of “Green Belt” and “Coastal Protection Area” are 482 ha and 162 Ha respectively. In general, there is a presumption against development within the “Green Belt” zone. The planning intention of this zone is primarily to promote the conservation of the natural environment and to safeguard it from encroachment by urban-type developments. With regard to the “Coastal Protection Area”, the intention of this zone is to protect the natural character of the shoreline, to safeguard the beaches and their immediate hinterland, and to prevent ribbon development in a haphazard manner.
South West New Territories Development Strategy Review
1.4.4 The current planning strategy for South Lantau is detailed in the “South West New Territories Development Strategy Review (SWNT DSR), Recommended Development Strategy (RDS) Final Report”. South Lantau, which is predominantly rural in character, is recognised for its unique scenery, including a number of beautiful beaches and unspoilt coastline and wooded headland areas. South Lantau Road, which is the only road transport link for the area, aligns parallel with the narrow coastal strip. Low-density residential settlements are mainly confined to the northern side of the road.
1.4.5 The RDS envisages that the potential of South Lantau as a popular recreation area for urban dwellers will be further enhanced as a result of the population growth in North Lantau. However, in view of the high conservation and scenic value of the area, any recreation development should be environmentally sustainable and the nature and scale of such development should be in harmony with the natural landscape and village setting. The RDS also stresses the need to maintain the high environmental quality of the area to sustain the recreation pursuits. The coastal areas are intended to be conserved mainly for water-based recreation and low density recreational uses such as aquatic sports, walking trails, camping grounds, holiday accommodations, cycleways, and eco-tourist centres.
South Lantau and Mui Wo Development Feasibility Study (Agreement No. CE 74/2001)
1.4.6 The RDS recognised the need to define the future role of South Lantau, and therefore recommended that an integrated planning and engineering feasibility study be undertaken to investigate the proposed scale of development and formulate up-to-date land use proposals for the area. The study will be undertaken by Territory Development Department (TDD) in mid 2002, and is called the “South Lantau and Mui Wo Development Feasibility Study”.
1.4.7 The principal goal of the study is to formulate a preferred land use scheme for South Lantau and Mui Wo in both planning and engineering terms, with particular emphasis on exploring the tourism / recreation potential, while conserving its natural environment in line with the RDS vision of balancing development and conservation needs in accordance with the principle of sustainable development. The study includes its own environmental assessments.
1.5 Comments from Relevant Public Bodies
1.5.1 During the periods when Government carried out its review of the possible solutions to improve the north-south vehicular access on Lantau and the Consultants undertook this Assignment, various public bodies were consulted. Members of these bodies generally expressed no objection in principle to the Project, and urged government to expedite the implementation of the Project. In addition, they made a number of comments and suggestions. These are presented in Appendix A, together with the Consultants’ responses.
1.6 Environmental Conditions in Absence of Improved Road
1.6.1 The majority of the proposed road, with the exception of the northern and southern ends, is situated within an overall rural area, with the surrounding land comprising country parks, open space and agricultural activities. The landscape along the route alignment contains many elements of outstanding natural beauty, including wooded hillsides, ridges lines of the Lantau and Sunset peaks and riverine valleys. This overall rural nature and minimised human disturbance, with the exception of the existing Tung Chung Road, is the key influence on the existing environmental conditions of the study area.
1.6.2 Noise levels for the majority of the study area are overall low, with the only major noise sources being the traffic of existing Tung Chung Road. Noise levels at the northern end of the alignment in Tung Chung are influenced by traffic from the Yu Tung Road. The southern end of the alignment connects with the South Lantau Road and thus, noise levels in this area are higher due to the presence of road traffic.
1.6.3 The background concentrations for nitrogen dioxide, respirable and total suspended particulates recorded at one of the closest EPD monitoring stations in Tsuen Wan were all well within the relevant Air Quality Objectives and, thus, the concentrations in the study area would be expected to be even lower given the overall rural nature of the location. Noise levels and pollutant concentrations would expect to be slightly higher at either end of the alignment, however, due to the presence of major roads and urban activity.
1.6.4 Ecologically, the study area is distinguished by the presence of key habitats, including secondary and plantation woodland, marshland, shrubland and clean natural streams, all of which support a variety of floral and faunal species, some protected and rare. Most of the streams are steep in the upland reaches and remain natural and unpolluted due to the lack of human habitation and pollution sources. The streams have been shown to support rich communities of freshwater fish and other invertebrates as well as flora and the Tung Chung Stream is has been identified as the second richest stream in Hong Kong for freshwater fish species.
1.6.5
Maintaining these
existing environmental conditions as far as practicable, has been a major
objective during the assessment and selection of a preferred route and through
the progressive design of the selected alignment.
1.6.6
In the event that
the proposed road improvement is not implemented, then the current traffic conditions on the existing road, which are already
considered poor, will deteriorate further with frequent traffic jams and
delays. Similarly, the number of accidents per year and the prolonged delays
caused by these accidents will either continue at the present rate, which is
already considered unacceptable, or most likely increase with more severe and
frequent accidents and subsequent road closures for rescue actions.
Furthermore, the demand for more TCRPZ permits from South Lantau residents will
escalate from its heavily suppressed condition, resulting in more frequent
friction with the Government, since the Government will not be able to meet the
demand in order to maintain the already poor traffic conditions from further
deterioration.
1.7 Benefits of the Improved Road
1.7.1
The design of the improved road has
been optimised to minimise the extent and magnitude of environmental impacts,
particularly the loss of ecologically important habitats. Retaining walls have
been used extensively to minimise the extent of the cut slopes, and bridges
have been used to traverse the ecologically sensitive streams.
1.7.2
However, the implementation
of the improved road will result in some impacts. To mitigate these, a
comprehensive range of measures has been recommended to reduce these impacts to
within acceptable levels. It is worth noting that some of these measures, will
not only mitigate the direct impacts, but will also enhance the existing
environmental conditions. In particular, the proposed remedial works to the
existing slopes using bio-engineering techniques (ie, hydroseeding instead of
spray applied concrete) will enhance the existing slopes, resulting in areas of
higher ecological value.
1.7.3
Furthermore, the
proposed special permanent drainage systems will avoid carriageway runoff from
being discharged into both the Tung Chung and Cheung Sha streams and also the
water gathering grounds. This is will be an improvement on the existing
conditions, whereby carriageway runoff is discharged directly into the small
streams, watercourses and hillsides directly below the existing road.
1.7.4
It is also likely
that CLP will replace its existing 33 kV overhead power lines across the
hillsides along the route corridor with new buried cables along the road.
Provision has been made under this project to accommodate these new cables, as
discussed in Section 2 of the report. This would not be possible without the
road improvement.
1.8 Detailed Environmental Impact Assessment
1.8.1
The Assignment
comprises a comprehensive environmental evaluation of the selected preferred
alignment option. This report constitutes the Final EIA Report.
1.8.2 The “Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study” has proposed development in the bottom of Tung Chung Valley. As such, the cumulative impacts associated with this development together with the improved road have been considered, as well as any future impacts on the development from the implementation of the improved road.
1.8.3 The purpose of the EIA is to provide information on the nature and extent of environmental impacts arising from the construction and operation of the Project and related activities that take place concurrently. This information will contribute to decisions on:
(i)the overall acceptability of any adverse environmental consequences
that are likely to arise as a result of the Project;
(ii)the conditions and requirements for the detailed
design, construction and operation of the Project to mitigate against adverse
environmental consequences wherever practicable; and
(iii)the
acceptability of residual impacts after the proposed mitigation measures are
implemented.
1.8.4
The objectives of
the EIA are as follows:
(i)to describe the Project and associated works together with the
requirements for carrying out the Project.
(ii)to identify and describe elements of community and
environment likely to be affected by the Project and/or likely to cause adverse
impacts to the Project, including natural and man-made environment;
(iii)to provide information on the consideration of
alternatives for avoiding and minimizing the environmental impacts to the
Country Park and the Water Gathering Ground and channels;
(iv)to identify and quantify emission sources and
determine the significance of impacts on sensitive receivers and potential
affected uses;
(v)to identify and quantify any potential landscape and visual
impacts, especially within the country park, and to propose measures to
mitigate these impacts;
(vi)to identify and quantify any potential losses or
damage to flora, fauna and natural habitats;
(vii)to identify any adverse impact on the water gathering
ground and to proposed measures to mitigate these impacts;
(viii)to identify any negative impacts on site of cultural
heritage and to propose measures to mitigate these impacts;
(ix)to identify the risk to works and road users due to
storage, transport and usage of chlorine at the water treatment work at Cheung
Sha.
(x)to propose the provision of mitigation measures so as to minimize
pollution, environmental disturbance and nuisance during construction and
operation of the Project;
(xi)to identify, predict and evaluate the residual
environmental impacts (i.e. after practicable mitigation) and the cumulative
effects expected to arise during the construction and operation phases of the
Project in relation to the sensitive receivers and potential affected uses;
(xii)to identify, assess and specify methods, measures and
standards, to be included in the detailed design, construction and operation of
the Project which are necessary to mitigate these environmental impacts and
reducing them to acceptable levels;
(xiii)to investigate the extent of the secondary
environmental impacts that may arise from the proposed mitigation measures and
to identify constrains associated with the mitigation measures recommended in
the EIA study, as well as the provision of any necessary modification; and
(xiv)to design and specify environmental monitoring and
audit requirements to ensure the effective implementation of the recommended
environmental protection and pollution control measures.
1.8.5
The assessment of construction related
impacts includes: air quality, noise, water quality, construction waste,
ecology, landscape and visual and hazard to life. The
assessment of impacts during the operation of the Project includes: air
quality, noise, water quality, ecology, landscape and visual, hazard to life
and heritage impacts.
1.9.1
The report is
divided into the following sections:
(i)
Section 2 provides an outline of the key elements of the Project. An indication of the main construction
activities and the anticipated equipment requirements are also presented
together with the predicted future operational traffic volumes;
(ii)
Section 3 outlines the environmental legislation, standards and
guidelines relevant to the study;
(iii)
Section 4 provides a description of the construction and operational air
quality impacts for the route and highlights mitigation requirements;
(iv)
Section 5 details the construction and operational noise impacts for the
alignment;
(v)
Section 6 describes the water quality impacts during the construction
and operational phases;
(vi)
Section 7 details the construction waste impacts;
(vii)
Section 8 presents the assessment of the terrestrial and aquatic
ecological impacts during the construction and operational phases;
(viii)
Section 9 outlines the construction and operation landscape and visual
impact assessment;
(ix)
Section 10 presents the hazard assessment;
(x)
Section 11 comprises the heritage impact assessment of the alignment;
(xi)
Section 12 details the cumulative impact assessment in respect of the
air, noise, water, waste, ecological and landscape and visual interface with
the proposed development in Tung Chung Valley;
(xii)
Section 13 details the initial outline of proposed EM&A requirements
for the Project;
(xiii)
Section 14 presents the summary and conclusions of the impact
assessment; and
(xiv)
Section 15 presents a summary of the environmental outcomes for the
project.