Section 2

As stated in Section 1.1, there are no gazetted beaches provided at the east region of the New Territories, apart from the beaches in the Sai Kung District. As such, Tai Po District Council (TPDC) has been requesting repeatedly for a beach development in Tai Po District Council for over the 10 years. Consequently, a Feasibility Study^([1]) was carried out and identified the current project site at Lung Mei, Tai Po as the location for the bathing beach. In accordance with the requirements of Sections 3.3.1 to 3.3.4 of the EIA Study Brief, this Section describes the need of the Assignment and site selection process for the identification of the site for the development of the bathing beach. Consideration of alternatives includes project locations, construction methods and sequences of works and justification for the adopted scenario.

2.2 The Need of the Project

As mentioned above, there is no beach facility in the east region of the New Territories, except in the Sai Kung District, which is very far from Tai Po District. Moreover, the existing swimming facility in the Tai Po areas could not satisfy the demand for a bathing beach. Therefore, the public has been requesting repeatedly to the LCSD for a beach development in the Tai Po District. Consequently, the Feasibility Study was carried out and identified in 2001 that the current project site as a feasible location for developing a bathing beach.

In light of the above, the TPDC strongly requested the development of a bathing beach at Lung Mei and members of the TPDC urged for early implementation of the Project. In a Legislative Council case conference on 20 April 2004, Members requested the Government to accord priority to this Assignment. This project was one of the 25 projects identified for priority implementation in the Chief Executive’s 2005 Policy Address and has the support of Home Affairs Bureau. It is considered that this Proposed Beach Development at Lung Mei will meet the increasing demand for swimming facilities, particularly the site located next to Ting Kok Road which is highly convenient to the public. The site is partly situated on an area zoned for open space use and there is a large piece of hinterland to accommodate various ancillary facilities of the proposed beach development. Moreover, the beach can serve a recreational function even during non-bathing season, ie playing in the sand, sunbathing and other beach activities.

The following options have been investigated before arriving to a conclusion that a bathing beach development should be proposed:

Option 1 – Do Nothing. No extra swimming facilities in the Tai Po area under this option.

Option 2 – Provision of Swimming Pool Facilities, such as the construction of a Sports Centre in Area 33, Tai Po, comprising a public indoor swimming pool with associated facilities. No engineering works to any coastal area in Tai Po under this option.

Option 3 – Construction of a Bathing Beach with bathing facilities in the coastal area of Tai Po.

The above alternatives have been investigated and evaluated from different perspectives and the results are presented in Table 2.1 below.

Options	Evaluation	Practicality of the Option
Do nothing	The public and TPDC’s request for beach facilities near Tai Po areas can not be satisfied.	Not practicable
Provision of Swimming Pool Facilities	It is understood that there will be a Sports Centre in Area 33, Tai Po proposed to be constructed, currently anticipated to be around mid-2009 to end-2011, which will comprise a public indoor swimming pool (25m long, 25m wide) with associated facilities. This project was also one of the 25 projects identified for priority implementation in the Chief Executive’s 2005 Policy Address. Even so, the added swimming pool would not satisfy the current demand for beach facilities in the Tai Po areas.	Not practicable
Provision of Bathing Beach at Alternative Locations within the Tai Po areas	The community demand for beach facilities can be met. The design criteria and environmental and engineering considerations in site selection will be further discussed in Section 2.3.	Practicable

In the view of the above, only the provision of bathing beach is considered practicable in satisfying the demand of the public and the TPDC for a beach facility in Tai Po. In addition to serve swimmers, the beach can also act all the year round as a recreational ground for non-swimmers, ie sand playing/sculpture activities, sunbathing and other beach activities etc.

There are a number of bathing sites considered in the Tai Po area and they are discussed in Section 2.3 but the preferred proposed Beach Development sited at Lung Mei would serve many local residents as well as residents from other parts of New Territories. The Proposed Beach Development would compliment and enhance the popular leisure area at Tai Mei Tuk, where there are numerous outdoor activities such as cycling, barbecue, windsurfing, boating and other water sports. It would be an additional and needed attraction for the local and Hong Kong residents, in particularly for family outings, not only to have fun swimming but also to enjoy the beach (ie sand playing/sculpture activities, sunbathing and other beach activities), the facilities and the natural environment. It is a project that has the support of the government and the Chief Executive as well as the local people. It will also meet the demand for more popular facilities and for a greater diversity of recreational activities in the Tai Mei Tuk area.

However, without this bathing beach, the community demand of beach swimming would not be met as there are no such facilities at Tai Po. The opportunity for such an attraction would be lost for the locals, residents’ afar and tourist alike. On top, the prospect to enhance the leisure area of Tai Mei Tuk area in Tai Po will never be realised. It should also be noted that Lung Mei is a non-gazetted beach and currently utilised by swimmers. Without this proposed bathing beach, the swimmers will still insecurely use this non-gazetted beach. Therefore, we conclude that the bathing beach development should be supported in light of strong public expectation for such an attraction and lack of beach facilities in the area.

2.3 Consideration of Alternative Project Locations

· It should have sufficient area for a development of a 200m long beach with a minimum beach area of 6,000m², serving 4,000 bathers during the swimming peak season; and

· The beach should preferably have no less than 10m wide sand part during very high tide so that the sufficient sun bathing area can be achieved. Ideally, there should be sufficient space in its hinterlands to accommodate other beach facilities such as changing room, toilets, shower area, storerooms, beach office, refreshment kiosk, etc.

From environmental and engineering points of view, the following criteria are also taken into account in the preliminary site selection process:

· The new bathing beach should be located along the shore with acceptable water quality (E. Coli concentration below 180 cfu per 100mL). It is preferable to be sited away from the industrial areas (ie Tai Po Industrial Estate) due to water quality concern;

· It is preferable to be located within a sheltered area (not subject to wave actions) to avoid sediment drift during operation and minimize the future maintenance requirement;

· It is preferred to have a soft bottom (ie sand, but not muddy bottom such as mudflat) and gentle slope to minimise dredging and sandfilling requirements during the development;

· It should be away from the existing fairway/navigation channel for bathing safety concerns;

· It is preferred to have nearby existing infrastructure (such as road and drainage systems) and supporting facilities to avoid extensive development works, causing environmental impacts to the surrounding areas.

Figure 2.1 shows all of the potential sites located within Tai Po District and geophysically suitable to be developed as a bathing beach. The potential bathing beach sites are mainly located in Plover Cove, Tolo Channel, Hoi Ha Wan and Long Harbour. To avoid impacts on the environmental sensitive areas, any potential bathing beach sites located in adjacent to or adjoining to the Country Park, Marine Park, Site of Special Scientific Interest, Special Area, Coastal Protection Area and identified key mangrove habitat have been eliminated for further consideration (Figure 2.2).

Therefore, with consideration of the above criteria, all of the potential bathing beach sites at the eastern region of Tai Po District including Long Harbour, Hoi Ha Wan and Tolo Channel were eliminated (Figure 2.2). It should also be noted that no potential bathing beach sites can be found at Tolo Harbour, the southeast of Tai Po District (particularly Tai Po town centre and along the coastline parallel to Tolo Harbour Highway). Comparison of the potential bathing beach sites (geophysically suitable) identified within the four regions including Plover Cove, Tolo Channel, Hoi Ha Wan and Long Harbour was summarised in Table 2.2.

Table 2.2: Comparison of the Potential Bathing Beach Sites (Geophysically Suitable) identified in Plover Cove, Tolo Channel, Hoi Ha Wan and Long Harbour within Tai Po District

	Plover Cove	Tolo Channel	Hoi Ha Wan	Long Harbour
Adjoining to Country Park ⁽¹⁾	No	Yes	Yes	Yes
Adjacent to Marine Park ⁽¹⁾	No	No	Yes	No
Adjoining to Site of Special Scientific Interest ⁽¹⁾	Yes, some of the potential sites	Yes	Yes	No
Adjacent to Special Area ⁽¹⁾	Yes, some of the potential sites	No	No	No
Adjoining to Coastal Protection Area ⁽¹⁾	Yes, some of the potential sites	No	No	No
Adjoining to identified key mangrove habitat ⁽¹⁾	Yes, some of the potential sites	Yes, some of the potential sites	No	Yes, some of the potential sites
Adjacent to Fish Culture Zone ⁽¹⁾	Yes, some of the potential sites	Yes, some of the potential sites	No	No
Having nearby existing infrastructure (such as road and drainage systems) ⁽²⁾	Yes	No	No	No
Shortlisted Sites Identified	Yes	No	No	No

Note: (1) Any potential sites locate adjoining to Country Park, Marine Park, Site of Special Scientific Interest, Special Area, Coastal Protection Area, identified key mangrove habitat and Fish Culture Zone will not be considered further due to environmental concern.

(2) Only potential sites of nearby existing infrastructure (such as road and drainage systems) will be considered as those sites can avoid environmental impacts due to the development of additional infrastructure.

Areas within Plover Cove are the remaining region in the Tai Po District considered to be suitable for the Proposed Beach Development (Figure 2.2). There are some potential sites identified within Plover Cove that avoid environmental sensitive areas, including Country Park, Marine Park, Site of Special Scientific Interest, Special Area, Coastal Protection Area, identified key mangrove habitat and Fish Culture Zone. In addition, those potential sites within Plover Cove have existing infrastructure which avoid additional development and associated environmental impacts. Apart from the suitable shore environment, Plover Cove can also be easy accessed by the public through the existing Ting Kok Road. The preferred site for the Proposed Beach Development should be situated away from the following environmental sensitive areas within Plover Cove:

Further to the review of the coastal environment along the coastline of Plover Cove, three potential sites, including Lung Mei, Shuen Wan and Sha Lan, are shortlisted for the Proposed Beach Development (Figure 2.3). All of the three sites are located in sheltered bay and therefore substantial sediment drift/ sand loss during operation would not expect to be anticipated.

Lung Mei is currently a non-gazetted beach located adjacent to Tai Mei Tuk which is a popular leisure area, and well away from the Ting Kok SSSI (about 500 m). From planning perspective, development of a bathing beach in adjacent to the existing leisure area can further enhance the recreational functions of the area. Part of the existing government land near the shore can be utilised and thereby minimise the reclamation area. It is also situated along the existing Ting Kok road and therefore additional transportation access or extensive associated infrastructure would not be required. However, drainage diversion of an existing box culvert and at lower course of Lo Tsz River is required.

Shuen Wan is located to the north of Shuen Chim

and to the south of Ting Kok SSSI (less than 100 m). As this potential site situated along the existing Ting Kok road, additional transportation access or extensive associated infrastructure would not be required. However, more reclamation as compared with Lung Mei will be expected as there is no existing government land that could be utilised building the bathing beach facilities. Due to the proximity of Ting Kok SSSI and mangrove habitats, the associated ecological and water quality impacts during the construction and operation of the Proposed Beach Development would be a concern. In addition, drainage diversion of Shuen Wan River is also required to adhere to the requirements of gazetted beaches.

Sha Lan is currently a non-gazetted beach and is over 500 m away from the Ting Kok SSSI towards the northeast. However, there is only one road (Sha Lan Road – two way single carriageway) leading into this area but ends up with a single lane access sloping into the village. The traffic flow along Sam Mun Tsai Road and Sha Lan Road would be expected to increase significantly due to the development of the beach. Upgrade of the exiting road access will be required for the proposed beach development should the site be selected. More reclamation as compared with Lung Mei will be expected as there is no existing government land that could be utilised for the bathing beach facilities. Drainage diversion of existing box culvert is also required to adhere to the requirements of gazetted beaches. In addition, this site would be closer to the Yin Tin Tsai East Fish Culture Zone in comparison with the proposed site at Lung Mei and therefore might be a greater concern to the fishermen.

2.3.3 Comparison of the Environmental Benefits and Dis-benefits of the Potential Sites

· The bathing beach location is well sited away from Ting Kok SSSI, as well as the mangrove habitat, and the existing waterpond at Tai Mei Tuk, which has been designated as a Conservation Area.

· It has limited dredging and reclamation, and so there is lower potential for environmental impacts particularly regarding water quality and waste management.

· There is an existing piece of land for building the beach facilities and the area of reclamation required can be minimised.

· There are potentially more trees to be affected due to the use of existing private land.

· Diversion of lower course of Lo Tsz River causing impacts on the stream (naturalness and ecological significance to be confirmed during detailed survey) cannot be avoided, but no unacceptable impacts will be anticipated due to the small scale of the works.

· Beach facilities are close to village houses causing potential air, noise and visual impacts, but no unacceptable impacts will be anticipated due to the small scale of the works.

· It is sited in the proximity of Ting Kok SSSI and Shuen Wan Egretry SSSI, as well as the mangrove habitat. The SSSI and mangrove habitats are potentially affected due to the construction and operation of the Proposed Beach Development.

· More reclamation is required, so that there is greater potential for environmental impacts particularly regarding water quality and waste management compared with Lung Mei.

· Diversion of lower course of Shuen Wan River is required and potential impacts on stream (naturalness and ecological significance to be confirmed during detailed survey) cannot be avoided.

· Beach facilities are close to village houses causing potential air, noise and visual impacts, but no unacceptable impacts will be anticipated due to the small scale of the works.

· The bathing beach location is well sited away from the Ting Kok SSSI, as well as the mangrove habitat.

· Diversion of stream/ river is not required, therefore no impacts on natural stream.

· It is close to the Sam Mun Tsai Egretry SSSI, Yim Tin Tsai & Ma Shi Chau SSSI, Ma Shi Chau Special Area and Yim Tin Tsai East FCZ. The FCZ is potentially affected due to the construction and operation of the Proposed Bathing Beach Development.

· More reclamation is required, so there is greater potential for environmental impacts particularly regarding water quality and waste management compared with Lung Mei.

· Provision of additional or enhancement of transportation access including road upgrading and provision of longer sewer connection (to local sewer) would be required. Impacts on terrestrial ecological resources will be comparatively larger.

· Beach facilities are close to village houses causing potential air, noise and visual impacts, but no unacceptable impacts will be anticipated due to the small scale of the works.

The key environmental concerns of the site comparisons are the extent of reclamation and dredging which will unavoidable to induce water quality, marine ecology and fisheries impacts. With consideration of the extent of dredging and reclamation, proximity of sensitive receivers such as Yim Tin Tsai East FCZ, provision of additional transport infrastructure and potential impacts (particularly water quality, waste management, marine and terrestrial ecology, and fisheries) to the environment, Lung Mei is considered to be the most suitable site for the proposed beach development in Tai Po (Table 2.3). Although the beach facilities will be located close to village houses causing potential air, noise and visual impacts, no unacceptable impacts will be anticipated due to the small scale of the works and with the implementation of good construction practices.

In summary, Lung Mei is considered to be the best location for the proposed beach development, which is located next to the existing road (Ting Kok Road) and at the sea front and having the least environmental impacts as discussed above. It should be noted that with the 60% sewerage connection rate and the gazette of the Tolo Habour Sewerage of Unsewered Areas Stage I Phase IIC (Agreement No. CE 18/94), as part of the Sewerage Master Plan Works for Tolo Habour Catchment, prior to the operation of the Proposed Beach Development, the water quality in the Lung Mei region will be improved and guaranteed. In addition to serving swimmers during the bathing season, the beach at Lung Mei can also provide all year round recreational ground for non-swimmers, ie playing in the sand, sunbathing and other beach activities. Consequently the Proposed Beach Development at Lung Mei would complement the existing amenity facilities and further diversify the recreational activities in the Tai Mei Tuk area.

Table 2.3: Comparison of Likely Overall Environmental Impacts on the Three Potential Sites

	Lung Mei	Shuen Wan	Sha Lan
Air Quality	Low	Low	Low
Noise	Low	Low	Low
Waste	Low	Moderate	Moderate
Water Quality	Low	Moderate	Moderate
Terrestrial Ecology	Low	Negligible	Low
Marine Ecology	Low	Moderate	Moderate
Fisheries	Low	Low	Moderate
Landscape and Visual (including tree felling)	Low to Moderate	Low	Low
Overall Likely Environmental Impacts	Low	Low to Moderate	Low to Moderate

Note: (1) Reclamation sizes of Shuen Wan and Shan Lan sites are estimated by provision of same carpak and beach building size as at Lung Mei site, taking into account any available existing land for the development.

(2) Dredging extents and volumes of Shuen Wan and Sha Lan sites are estimated under an assumption that their dredging depth and beach size will be very similar as Lung Mei site.

2.4 Consideration of Alternative Design

The feasibility of following alternative designs has been investigated in this Assignment as discussed below for the preferred option at Lung Mei. In addition, the design and construction of each element of the works were considered in light of construction methods and sequencing of works:

4 options of the bathing beach configuration at Lung Mei have been investigated in the Feasibility Study and are shown in Appendix A. The option layouts were developed to study different orientations of car park, beach building, seawall requirements, etc in order to facilitate the beach users, reduce construction cost and minimise the environmental and engineering impacts. An option evaluation was also carried out on each layout and its location, which were based on the following criteria:

Considering the various pros and cons of each option as shown on Table 2.4, it was recommended that Option 1 would be adopted for further investigation and development. From Option 1, the car park site and beach building were shifted eastward to avoid decking over the Lo Tsz River. The final recommended beach layout in feasibility study stage is shown on Figure 3.5 of Appendix A.

Table 2.5: Comparison of Layout Options During Investigation Stage

Considerations	Preferred Option	Option A (West)	Option B (East)	Option C (South)
*Environmental Issues*
Extent of Reclamation	Approximate 1.02ha	Similar to the Preferred Option	Greater than the Preferred Option (could be up to around 40% more)	Greater reclamation area than the Preferred Option; (could be up to around 50%) Longer groynes to be required to ensure shoreline stability
Extent and Quantity of Dredging	Approximate 5 ha and 10,000 m³	Extent similar to the Preferred Option; Dredging quantity to be larger than the Preferred Option due to shallow water at the west	Extent and quantity similar to the Preferred Option	Extent and quantity to be more than the Preferred Option, as there is a sudden level drop further out the sea.
Sandfilling requirement	Approximate 37,500m³	Slightly less than the Preferred Option	Slightly greater than the Preferred Option due to deeper water at the east	Greater than the Preferred Option due to deeper water at the south
Distances from Environmental Sensitive Receivers	About 500m from the Ting Kok SSSI; About 400m from Conservation Area	Closer to the Ting Kok SSSI and away from Conservation Area compared with the Preferred Option	Away from the Ting Kok SSSI but closer to Conservation Area compared with the Preferred Option	Similar to the Preferred Option but comparatively closer to the Fish Culture Zone
Impacts on Trees	157 trees identified within the Project site and 119 to be affected	More trees to be affected due to occupation of the existing private land	Affected trees to be slightly less than the Preferred Option	Similar to the Preferred Option
Impacts on the estuary of Lo Tsz River	No works	Decking of the Lo Tsz River required	No diversion works of Lo Tsz River	Similar to the Preferred Option
*Impacts on the existing infrastructures*	One existing box culvert to be affected, requiring drainage diversion works;	Similar to the Preferred Option	Extensive impacts on the existing box culverts, other drainage outlets and the existing seawall, which will require modification or diversion works	Similar to the Preferred Option
*Land Resumption*	Approximately 1ha	More private land resumption required	Slightly less than the Preferred Option	Similar to the Preferred Option
*Impacts on marine facilities and transportation*	12 existing mooring buoys to be affected	Similar to the Preferred Option	Numbers of the affected existing mooring buoys similar to the Preferred Option; Conflict with and limiting the existing leisure activities	More existing mooring buoys to be affected; Closer to the existing activity zone designated by the Tai Mei Tuk Water Sports Centre
*Overall Construction Cost*	N/A	Higher than the Preferred Option	Higher than the Preferred Option	Higher than the Preferred Option
*Preferability*	Preferred Option to achieve a balance with different considerations	Not Preferred due to encroaching into the Ting Kok SSSI and decking required at Lo Tsz River	Not Preferred due to involving greater reclamation, extensive modification/diversion works for the existing box culverts and seawall with significant potential environmental impacts during construction	Not Preferred due to greater reclamation area required, as well as longer groynes and larger site boundary. Minimising reclamation is one of the key requirements of this Project

Furthermore, several configurations of the proposed beach, carpark and building layout have been investigated, in order to identify an optimal solution to fulfil all the environmental and engineering requirements as listed below:

Several configurations of the proposed beach, carpark and building layout have been investigated, in order to identify an optimal solution to fulfil all the environmental and engineering requirements as listed below:

· Hydrodynamic Analysis

This was carried out for the proposed groynes and beach profiles to study their stability and recommend a suitable beach orientation, which would minimise sand loss, long-term sandfilling maintenance requirements and optimise the proposed groyne lengths.

· Optimisation of Land Uses

The studies were carried out to minimize the overall reclamation requirement with consideration of the following development scenarios:

- The level of the car park and ground compound of the proposed bathing beach facilities and administration building is restricted by matching in with the existing level of Ting Kok Road. The general road level of Ting Kok Road connecting the car park is from around +5.8mPD (east of project site boundary) to +6.6mPD (west of project site boundary) with the road level at the car park entrance at around +6.3mPD. Therefore, with a slight gradient for drainage and kerb height, a general level of +6.6mPD has been set for the level of the beach buildings.

- There was an agreed requirement to maintain a buffer zone of 10m between the beach building and the high water mark at extreme storm conditions of 1 in 100 years, maintaining a beach level at +4.6mPD. However, this would have meant a larger reclamation area and increased area for the bathers at high water mark conditions. This requirement was subsequently reduced to a modelling of a design wave condition for a 1 in 20 years return period and it was ascertained that under this condition an area of 6,000m² above the high water mark (HWM) was achieved. This also reduced the length of the groynes.

- With the 1 in 20 years return period, the top level of the beach at equilibrium will be at +3.8mPD while the mean higher high water level at the project site is +2.0 mPD. Moreover, the proposed beach will provide an area of 6,000m² above HWM to accommodate 4,000 beach goers in the peak season. In addition, the minimum clearance of 10m between the high water level and beach building will be maintained at about +3.1mPD, which corresponds to 1 in 4 years return period.

- A decked car park was proposed, thereby reducing the footprint of the parking area but this option was not preferred as it would have an increased visual impact. Conversely, most of the beach buildings are located towards the beach, away from the Ting Kok Road, which will introduce fewer disturbances to the environment. In addition, the proposed car park has to be designed to accommodate manoeuvrings of coaches around the car park as they require a large turning cycle.

- The distances between buildings for the Proposed Beach Development were limited to the requirement of the Fire Services Department for EVA, which is 6m minimum.

- Designing the buildings closer together or align them side by side, such as the gents and ladies changing rooms and toilets. However, this would limit the circulation movement for the bathers inside the changing rooms and also limit the movement of bathers on the paved areas going to and fro from the east side of the beach and the car park. Therefore this was not preferred.

- The building for the equipment / machinery stores for catamarans, motorized boats and beach transporters had to be situated close to the centre of the beach paved area, as this would be the ideal location for emergencies within the beach area.

· Minimisation of Dredging

To minimise the environmental impact, the removal of large quantities of sediment had to be avoided. Therefore, a minimum of 500mm depth of sediment removal has been proposed, so as to remove all boulders, cobbles, stones and silty material within the proposed beach area prior to sand filing. The above materials and debris are required to be removed as they may be exposed during seasonal changes of the beach profile and platform, which would be dangerous to the beach users. Moreover, the proposed dredging depth at the groynes is around 0.5m to 1m for the levelling of the groyne foundation which is essential for the groyne stability and safety of the beach users.

Therefore, in light of the above, it is considered that the present arrangement and layout is the most optimal in terms of environmental impact, cost impact and technical viability, whilst meeting the requirement of the LCSD and the Brief.

2.4.2 Road Access

Different scenarios of ingress/egress to the proposed car park have been investigated and it is considered that the current arrangement best suits the site constraints and requirements. The proposed ingress/egress is constrained by the requirement of the Transport Planning Design Manual, where it states that new access should be situated at least 40m away from existing accesses on the near or far side of the road. Therefore, as there are two existing accesses leading from Lo Tsz Tin village, the current access layout is the most preferred.

On the west side, there is the existing Lo Tsz River. The development has been designed to avoid encroaching into that area as much as possible for environmental reasons. However, there will be a proposed culvert, at the upstream end of Lo Tsz River where it meets the Ting Kok Road, designed as a transition to connect the existing culvert and the proposed open channel with gabion baskets. The paved area above the proposed culvert will allow a footpath to be constructed there. On the other hand, at the east side of the beach development, there is an existing bus layby and the beginning of an existing retaining wall, retaining the Ting Kok Road, which the development was designed to avoid as this could have meant the demolishing of the retaining wall and therefore, would affect the construction duration and cause disturbance to the public. The overall road access configuration was designed in light of the constraints above and is shown on Figure 2.4.

It is envisaged that the construction method for the road works will be conventional; however, 4 stages of temporary traffic arrangement are anticipated to complete the roadworks, drainage, sewerage and utilities works.

2.4.3 Open Channel with Embankments Baskets at Western End of Bathing Beach

To comply with the clause 5.3.2 under Chapter 10 of the Hong Kong Planning Standards and Guidelines, that no discharge outlets for effluent disposal should be located within 100m of any gazetted beach, there is the need to divert the flow from the existing culvert, at the western section of the bathing beach development. Therefore, different designs for the diversion were studied, such as a 6.8m rectangular diversion channel that was proposed in the feasibility study, a culvert and a trapezoidal reinforced concrete channel. However, in accordance with the Technical Memorandum on EIA process (EPD, 1997), the general policy or approach for mitigating impacts on natural streams/rivers is in the order of priority, avoidance, minimisation and compensation, therefore, an open channel with gabion embankments is proposed as shown on Figure 2.5.

Planters will be provided along the top of the gabion embankments to mitigate visual impacts from Ting Kok Road and to re-creat a greening environment of the existing Lo Tsz River. The option of providing more planters on the gabion steps has been considered. However, it may affect the drainage performance but planters on the top of the embankments are adopted.

It is anticipated that the sheet piling as temporary works for the gabion channel will be carried out using a silent piler, to minimise the construction noise impact. In addition, the construction of the gabion baskets for the channel wall and channel bed will be mostly manual and therefore be more environmentally friendly than the conventional reinforced concrete open channels.

2.4.4 Culvert at Eastern End of Bathing Beach

As discussed in Section 2.4.3, the culvert at the east side of the beach development had to be diverted as well in order to comply with clause 5.3.2 under Chapter 10 of the Hong Kong Planning Standards and Guidelines. We have looked at the preliminary design carried out in the feasibility study and consider that the proposal of constructing a culvert within the carriageway will slow down the progress of construction. Therefore, we propose to reprofile the existing culvert at the outlet and divert a new culvert with a right angle turn to the east by around 90m and parallel with the existing sea wall as shown on Figure 2.6.

This proposal will not necessitate the digging up of the existing road and therefore, avoid longer and more extensive temporary traffic management periods as well as reducing the dust and noise impacts. To ease construction difficulties and minimize the environmental impacts, we propose that the box culvert be constructed as pre-cast and cast in-situ segments and therefore the pre-cast segments can be lifted onto the coast from the Ting Kok Road.

2.4.5 Design of Groynes

The preferred groyne layout option include two rock armour groynes comprising a western groyne length 100m and an eastern groyne length 120m, both from the building line as shown on Figure 2.7 to protect the proposed sandy beach. The design beach to be constructed consists of a 1:12.5 upper slope above +2.0mPD and 1:15 below, with the beach recharge offshore of the natural step consisting of a 1:25. The crest height of beach at design is +4.6mPD and the height of groyne at crest is also +4.6mPD for 5m and then basically falls towards the sea at 1 in 25 as shown on Figures 2.8 and 2.9. The groynes are designed to retain the beach sand, with the sand profile at construction as shown on Figures 2.7 to 2.9. During the natural course of events; the beach will reach an equilibrium profile, also shown on Figures 2.7 to 2.9.

The proposed groynes will be constructed with a primary rock armour layer and a rock fill core as shown on Figure 2.10. To enhance the landscaping areas within the Project site, a planter is proposed on each groyne with minimum dimensions of 1.5m (H) x 1.5m (W). The proposed arrangement of the groyne and planter is also depicted on Figure 2.10.

Apart from the preferred beach layout, other options for increasing the groyne lengths have also been examined. Two other options were to have the groynes (both east and west groynes) extended to 135m as well as 180m to the sea, so that the beach material at the toe of the beach slope would be less susceptible to movement under extreme storm conditions. However, this would increase the construction quantities, which would not be justified in consideration of environmental and cost impacts for a longer groyne as well as more dredging and sand filling required.

In addition, wave and sediment modelling was conducted for the above scenarios as presented in Appendix B and it was demonstrated that the beach material would basically be retained by the groynes for the preferred layout scheme, due to the current location of the beach.

Other options for the groyne construction were investigated, such as concrete blocks and timber. However, rock armour was chosen as it would be simpler and more natural in appearance. Armour rock will be more ecological beneficial and require little or no maintenance.

It is anticipated that the groyne construction will commence prior to the sand filling. The west groyne will most probably be constructed first. Dredging for the groyne would be carried out by land plants for locations above the low water mark, whereas a grab dredger will dredge the seabed for the groyne below the low water mark. The placing of sand is expected to be carried out using a backfilling barge with a conveyor belt, most probably from west to east.

2.5 Consideration of Alternative Construction Methods and Sequence of Works

2.5.1 The basic construction methods were discussed in Section 2.4; however, the following alternative construction methods were also looked into:

· Silent piler for the installation of sheet piles as temporary works in the construction of the gabion channel and for deep excavation for drainage works was proposed to reduce the noise impact;

· Pre-cast sections for the lower half of the culvert at the east end of the beach, to minimise temporary traffic management as well as noise, dust and material (formwork) on site. The duration of the construction works could also be reduced;

· Precast concrete units for the retaining walls for the boundary of the car park and bathing beach building to minimise noise, dust and material on site. The duration of the construction works could also be reduced;

· Gabion baskets are used for the channel diversion at the west end of the bathing beach, and therefore less construction plants will be used for the channel wall and bedding. This will reduce the construction noise impact as well as material used on site;

· The justifications for dredging are addressed in Section 2.4.1. All dredged material is proposed to be disposed by sea (either to South Cheung Chau dumping ground or East Sha Chau mud pits subject to the results of sediment testing) and thereby reducing the land transport by trucks; and

· It is proposed to use the existing rocks on site for the gabions and groyne construction if the specifications of the rocks are met.

2.5.2 During the construction phase, the estimated quantities have generally been reduced since the feasibility stage for the overall construction works, which was due to alternative construction designs and revising some of the requirements of the EIA Study Brief, as shown below:

i. Estimated quantity of land-based excavated materials is summarised below:

Description for Construction Works	Volume (m³)
Description for Construction Works	Excavation	Demolition
Building & Landscaping	800	10
Works along Ting Kok Road (including local road widening, drainage, sewerage, watermain & utilities connections)	600	450
Works at Carpark (including drainage & sewerage works, and carpark formation)	4,000	-
Vertical Seawall/Retaining Wall	2,000	-
Western Drainage Channel ⁽¹⁾ (i.e. Open channel and box culvert)	4,500	10
Eastern Box Culvert ⁽¹⁾	1,900	-
Total	13,800	470

Note 1: Construction of the proposed western drainage channel and eastern box culvert will be carried out above high water mark (HWM) and therefore considered as land-based construction activities. No dredging will be required for the proposed drainage diversion works.

It has been estimated that about 60% of the above land-based excavation can be reused, that is around 8,280m³.

ii. Estimated Dredging Quantities:

· Dredged plan area is approximately 5.0ha.

· Dredging volume for the seabed, groynes and seawall is 10,500m³.

iii. Estimated Reclamation Area for the overall development is about 1.02ha
(or 10,200m²) and comprises the following:

Description	Reclamation Area (m²)
For bathing beach area	9,500
For groynes	700
Total	10,200

iv. Estimated Rocks and Filling Quantities:

Marine Works

Description	Volume (m³)
Description	Rock/Rockfill	Sand Fill
*Beach Construction*	-	37,500
*Groyne construction* · Armour layers · Rockfill core	3,000 1,600	- -
Total	4,600	37,500

Land Works

Description	Volume (m³)
Description	Rock/Rockfill	Granular Fill /Aggregates	Soil /Sand Fill
*Carpark & Beach Buildings*
· Backfill of retaining wall*	-	-	21,000
· Building construction	-	-	100
· Sub-base of carpark	-	2,000	-
*Western Drainage Channel*
· Foundation of box culvert	40	-	-
· Rip-rap bedding of open channel	300	-	-
· Gabion embankments	1,400	-	-
· Armour layers at outfall	120	-	-
· Rockfill slopes at outfall	120	-	-
· Backfill of box culvert and embankments	-	-	1,900
*Eastern Box Culvert*
· Foundation	800	-	-
· Backfill of box culvert	-	900	-
· Filling of Planter Wall	-	-	600
· Sandfill for temporary excavation	-	-	600
*Works along Ting Kok Road*
· Sub-base for local road widening	-	400	-
· Drainage, sewerage and utilities	-	-	500
Total	2,800	3,300	24,700

Note: * Land formation for the proposed carpark and beach building.

v. GFA of new building/structure according to Building Ordinance = 2,245m².

2.5.3 The sequences of works for the construction works.

The comparison of different sequence of works, together with the environmental benefits and dis-benefits are presented in Appendix C1. The following sequences of works are discussed;

1. Site Formation for Car Park & Beach Building Area

2. Road Widening, Roadworks, Utilities, Drainage and Sewerage Works

3. Groyne Construction, Dredging and Sand Filling

The preferred sequences of works for each element of construction works are presented in Appendix C2 and summarised below:

1. The construction of ramp, staircase, vertical seawalls, retaining walls and their foundations.

2. Construction of beach buildings and their foundations

3. Construction of paving area for car park.

4. Road pavement construction (this work will be carried out concurrently or in stages with the construction works for utilities, watermain, drainage and sewerage):

4.1 Construction of new sewage pipeline and manholes

4.2 Construction of new drainage pipeline gullies

4.3 Laying of watermains and utilities

5. Construction of western box culvert.

6. Construction of western drainage open channel.

7. Construction of modification works on existing box culvert

8. Construction of 90m long eastern box culvert.

9. Groyne construction.

10. Dredging and sand filling.

2.6 Selection of Preferred Scenario

The current Project site is situated along the existing coastline of Ting Kok Road and opposite to the Lung Mei Village at Tai Po. Part of the original proposed site is vegetated with grass, shrubs and trees; however, the other part comprises of an existing sandy beach assessable from the southbound of Ting Kok Road. There are no residential dwellings at the proposed beach site and the general environment of the existing beach is very pleasant, with Ma Shi Chau to the south and the picturesque Pat Sin Country Park towards the north.

The existing site area above high water mark (HWM) is about 8000m². The beach water is very shallow over a long distance from the current high water mark. However, based on the Wave and Sediment Modelling Report, the normal wave condition at Lung Mei area is considered as very mild. Our study concluded that the proposed bathing beach location and layout would be less susceptible to erosion due to surge overwash and longshore sediment transport, such that the sediment transport and siltation under the influence of environmental forces during the operational phases will be minimal.

Moreover, the present site location (at Lung Mei) is ideal in consideration of environmental factors as discussed in Section 2.3 (including minimised extent of dredging and reclamation, and located away from sensitive receivers, including Ting Kok SSSI and FCZ), and which will complement and be conveniently located to the existing facilities/activities in the Tai Mei Tuk area. Given the discussion in Sections 2.4 & 2.5, the proposed construction method and sequences of works, detailed in Section 3, are the preferred scenario that will maximise environmental benefits and minimised adverse environmental effects arising from the Project.

( [1]) ArchSD(2001). 128ML – Feasibility Study for Proposed Beach Improvement Work at Lung Mei Beach, Tai Po, Final Report

Review on	Option 1	Option 2	Option 3	Option 4
Utilisation of beach area and facilities	As the car park sets back from the beach area, a longer waterline is provided, this may be of interest from recreation point of view. Eastern half of parking area to be probably occupied first, as it is closer to the facilities house and the beach area. Longer walk is required for other users coming late.	The car park is close to the main beach area. It is more convenient for beach users. As compared to Option 1, the facilities house has a longer distance to the main beach area. Also a shorter waterline is provided.	The car park is split into two portions and the facilities house is located at midway between the two parking areas. It is convenient for beach users to park their cars and access to the facilities house. The facilities house is close to the main beach area; however, a shorter waterline is provided as compared to Option 1.	Two rows instead of four car pots are provided. This provides more usable beach area, and results in a long waterline. Eastern half of parking area to be probably occupied first. Longer walk from west of the car park area for other users coming late
Extent of sand filling work on seaward	Approximate 2,000m²	Approximate 4,000m²	Approximate 4,000m²	Approximate 2,000m²
Sand stability control	Better because of presence of revetment or groyne.	Wave turbulence likely created at southeast corner of car park resulting in local scouring and increasing the loss of sand. A groyne may be required to overcome this situation.	Same as Option 2	A groyne likely to be required to prevent the loss of sand.
Construction cost	Moderate; groyne construction is required.	Expensive because of seawall construction and either regular replenishment of sand or provision of a groyne.	Same as Option 2	Cheaper
Impact on environment	Construction of car park decking close to the SSSI and wetland	A longer distance to the SSSI and wetland.	Same as Option 2	Same as Option 1
Air pollution to beach user due to traffic at Ting Kok Road	Poor because sand area close to Ting Kok Road	Better because of car park area and the facilities house shifted away the Road.	Same as Option 2	Same as Option 2
Traffic control	Better traffic circulation flow inside car park. Alternative route available for diversion traffic flow if one of the routes is blocked.	Same as Option 1	Same as Option 1 but increase in junctions of car park exit and entrance interface the traffic flow at Ting Kok Road.	Poor traffic circulation inside car park.
Channelisation of natural stream and maintenance	A section of some 35m long channel will be decked. Maintenance of the decked channel may be of concern.	Channel will not be decked.	Same as Option 2	Same as Option 1

2. CONSIDERATIONS OF ALTERNATIVES

2.1 Introduction

2.2 The Need of the Project

2.3 Consideration of Alternative Project Locations

2.4 Consideration of Alternative Design

2.5 Consideration of Alternative Construction Methods and Sequence of Works

2.6 Selection of Preferred Scenario