Alignment of Options 2 & 3. Lam Tin. Tseung Kwan O Town Centre South. Ocean Shores. Cemetery. Cross Bay Link. Alignment Option 1

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1 Alignment of Options 2 & 3 Tseung Kwan O Town Centre South Alignment Option 1 Cross Bay Link Note: The above alignments are for illustration only. The final alignment is subject to further study and detailed design. August 2010

2 P urpose This consu ltation digest aims to give the general public an introduction tio of the alignment options of Tseung Kwan O Section for Tseung Kwan O Lam Tin Tunnel (TKO-LT Tunnel). The proposed align me nt opt ptions in this consultation digest are for preliminary consideration. We would like to seek pub lic views on these options for appraisal and fu rther improvement. We will then draw up a preferred road scheme and consult you again in the next stage of public consultation. I ntroduction TKO LT Tunnel, together with the proposed Trunk Road T2 (T2) in Kai Tak Development and Central Kowloon Route, will form Route 6 in the strategic road network. Upon completion of Route 6, traffic between Kowloon and TKO areas can go through Route 6. TKO-LT Tunnel is a dual-two lane highway approximately 4.8km in length connecting TKO at Po Yap Road / Po Shun Road in the east with proposed T2 in the West. It will also provide slip roads for direct connection to Eastern Harbour Crossing. After the completion, TKO-LT Tunnel together with Cross Bay Link (CBL) will form a new road network to meet the long term transport needs of TKO. N Central Kowloon Route Trunk Road T2 Cross Bay Link Tunnel Fig. 1 1

3 A lignment Option Developed in Previous Study (The Original Scheme) In previous Feasibility Study for Further Development of TKO, we have developed an alignment option for TKO-LT Tunnel. Below are the key features of this option: About 2.2 km long tunnel section at Tseung Kwan O Passing under Junk Bay Chinese Permanent in the form of tunnel S-curve alignment to keep the toll plaza alongside the shoreline such that visual and water quality impacts in Junk Bay can be reduced About 12 ha* of reclamation in Junk Bay to accommodate the toll plaza, associated facilities and the connection roads *: 1ha = Area of 1 standard football pitch Tseung Kwan O Town Centre South Tunnel Chiu Keng Wan Shan P2 Road Junk Bay Reclamation Area Cross Bay Link Illustration of the Reclamation Area 2

4 P ublic Consultation for TKO-LT Tunnel During April to July 2009, we held Focus Group Meetings with TKO residents, professional institutes and green groups respectively to seek their initial views on the Original Scheme. Existing Natural Shoreline at Western Coast of Junk Bay M ajor Public Views on Tseung Kwan O Section To reduce the extent of reclamation at Junk Bay To preserve the existing natural shoreline along the western coast of Junk Bay To address the environmental impacts, particularly implications on the marine ecology at Junk Bay To straighten the tunnel alignment to reduce the travelling distance F urther Study To address the public concerns on reclamation and preservation of natural shoreline in Junk Bay, we have reviewed the alignment at Tseung Kwan O Section, including the feasibility of locating the toll plaza at Kwun Tong area. However, our study found that there would be insufficient land space to accommodate the toll plaza and the Interchange* at the same time. Having regard to the infeasibility of locating the toll plaza at Kwun Tong area, we have further studied alternative alignment options with a view to reducing the extent of reclamation, the impacts on existing natural shoreline at Junk Bay, and the tunnel length. We have considered three alternative alignment options: To replace reclamation of the Original Scheme by a toll plaza island (hereinafter referred as The S-curve Alignment Option with Toll Plaza Island ) to preserve the natural shoreline; To straighten the tunnel alignment with a toll plaza island (hereinafter referred as The Straight Tunnel Option With Toll Plaza Island"); and To straighten the tunnel alignment without a toll plaza island (hereinafter referred as The Straight Tunnel Option Without Toll Plaza Island ). Brief description of these options is given in the following pages. *: Interchange will link TKO-LT Tunnel, Trunk Road T2, Eastern Harbour Crossing, and Cha Kwo Ling Road together, facilitating drivers to travel to/from different areas. 3

5 O ption 1: The S-curve Alignment Option with Toll Plaza Island Below are the key features of this option: Tunnel length and S-curve alignment similar to the Original Scheme An artificial island to be constructed to accommodate the toll plaza and associated facilities Existing natural shorelines of about 1.2 km along the western coast of Junk Bay preserved Area of reclamation reduced to 9.5 ha Compared with the Original Scheme, impacts on the Tseung Kwan O marine ecology (including coral and the Philippine Neon Goby*) would be reduced Since the S-curve alignment runs under the Junk Bay Chinese Permanent, the risk of settlement on the graves, tombs, etc. in the cemetery would be relatively high as compared with other options The S-curve alignment would have the possibility of hitting the hydrothermally-altered granite zone and dyke, which is risky in tunnel construction (including construction cost and time) The S-curve alignment would pass through a relatively long length of mix of soft ground/soft and hard ground at the TKO tunnel portal. Tunnel excavation in such ground condition is relatively risky and difficult. It is more susceptible to ground collapse and this will require a large amount of temporary supporting during the construction. *: Philippine Neon Goby is a relatively rare species in Hong Kong. It is reported that its global population is declining. Philippine Neon Goby Tseung Kwan O Town Centre South Tunnel Chiu Keng Wan Shan Reclamation Area P2 Road Junk Bay Cross Bay Link Artificial Island Tseung Kwan O Interchange Based on the potential geotechnical risks, it is considered that this Option is technically undesirable. Illustration of Artificial Island 4

6 Piled Deck Structure O ption 2: The Straight Tunnel Option with Toll Plaza Island Below are the key features of this option: An artificial island and a piled deck structure to be constructed to accommodate the toll plaza and associated facilities Existing natural shorelines of about 1.2 km along the western coast of Junk Bay preserved Area of reclamation reduced to 9.5 ha Straight tunnel alignment would not pass under the Junk Bay Chinese Permanent Compared with the Original Scheme, length of main road would be reduced by about 600m (including 400m reduction in length of tunnel section at Chiu Keng Wan Shan), however, length of slip roads connecting Road P2 would be longer Compared with the S-curve alignment option, the possibility of hitting the hydrothermally-altered granite zone and dyke is relatively low and therefore the risk in tunnel construction is relatively low. The artificial island and the piled deck structure (approximately width 60m, length 140m) would protrude into Junk Bay, which would create serious visual impact The longer slip roads connecting TKO-LT Tunnel and CBL will impose adverse visual impact to Junk Bay and defeat the feature bridge design of CBL Due to the orientation of the toll plaza, curvature of all the slip roads will be extremely sharp compared to that of other options Due to the constraints in design, configuration of the toll plaza would be less streamlined to the tidal current, which would have serious impact on the local tidal flow direction and velocities and potentially cause significant accumulation of pollutants discharged into the embayment According to the recent marine ecological surveys, high diversity and abundance of corals are recorded from area of the proposed protruding toll plaza. A previous study on octocoral and black coral conducted by AFCD/ CUHK* also reported similar findings. Direct adverse impact on these coral communities of ecological interest due to reclamation and the decked structure is anticipated. *: "Reference Collection and Study on Octocorals and Black Corals in Hong kong Water" (unpublished) Tunnel Chiu Keng Wan Shan Reclamation Area Tseung Kwan O Town Centre South P2 Road Junk Bay Cross Bay Link Based on the aforesaid serious environmental and visual impacts, this Option is not recommended. Illustration of Toll Plaza Island 5

7 O ption 3: Straight Tunnel Option without Toll Plaza Island Below are the key features of this option: Existing natural shorelines of about 1.2 km along the western coast of Junk Bay preserved Area of reclamation reduced to 3 ha (mainly for construction of connection roads) Straight tunnel alignment would not pass under the Junk Bay Chinese Permanent Compared with the Original Scheme, length of main road would be reduced by about 600m (including 400m reduction in length of tunnel section at Chiu Keng Wan Shan), while length of slip roads would be similar Compared with the S-curve alignment option, the possibility of hitting the hydrothermally-altered granite zone and dyke is relatively low and therefore the risk in tunnel construction is relatively low. No toll plaza and associated bus-bus interchange at tunnel portal to be provided Arrangement of tolling facilities to be further considered Minimum environmental impacts (including water quality, marine ecology, noise, air and visual) Coral (Echinogorgia SP) Tunnel Chiu Keng Wan Shan Reclamation Area Tseung Kwan O Town Centre South P2 Road Junk Bay Cross Bay Link Based on both the engineering and environmental consideration, this Option is viable. Illustration of TKO Interchange 6

8 C omparison amongst the Options Features The Original Scheme (1) The S-curve Alignment Option with Toll Plaza Island (2) The Straight Tunnel Option with Toll Plaza Island (3) The Straight Tunnel Option without Toll Plaza Island Alignment S-curve S-curve Straight Straight Length of main road 4.8 km 4.8 km Shorter than the Original Scheme by 600m, but longer slip roads connecting Road P2 Shorter than the Original Scheme by 600m Would toll plaza and associated bus-bus interchange be provided? Yes Yes Yes No, tolling facilities to be further considered Total Reclamation area (ha) 12ha 9.5ha 9.5ha 3ha Would the natural shoreline be preserved? No Yes Yes Yes Geotechnical risks in tunnel construction High Because S-curve alignment would pass the mix of soft & hard ground foundation underneath and would have possibility of hitting the hydrothermallyaltered granite zone & dyke High Because S-curve alignment would pass the mix of soft & hard ground foundation underneath and would have possibility of hitting the hydrothermally-altered granite zone & dyke Low Possibility of hitting the hydrothermally-altered granite zone and dyke is relatively low Low Possibility of hitting the hydrothermally-altered granite zone and dyke is relatively low Visual impact Medium High Very High Low Other environmental impacts High marine ecology impact due to reclamation Medium marine ecology impact due to slightly-reduced reclamation Serious environmental impacts (particularly water quality & marine ecology) due to the protruding of reclamation into Junk Bay Lowest environmental impacts due to minimum reclamation required Construction Cost Approximately HK$8.0 billion less than the Original Scheme by HK$0.3 billion less than the Original Scheme by HK$1.2 billion less than the Original Scheme by HK$1.7 billion C onclusion Option 1 (The S-curve Alignment Option with Toll Plaza Island) and Option 2 (The Straight Tunnel Option with Toll Plaza Island) provide undesirable performance from the aspects of geotechnical risks in tunnel construction and environmental impacts (including water quality, marine ecology and visual impacts), while Option 3 (The Straight Tunnel Option without Toll Plaza Island) provides better performance in most of the aspects. C onsultation and Next Step We would like to hear your views on the alignment options of Tseung Kwan O Section of TKO-LT Tunnel. We will take into consideration of your views to select the preferred option for further assessments and refinements. We will then draw up the most preferable scheme and consult you again in next stage of public consultation. Y our Views and Comments are welcome Please forward your written comments by mail to Civil Engineering and Development Department New Territories East Development Office Suite 1213 Chinachem Golden Plaza 77 Mody Road, Tsim Sha Tsui, Kowloon; or by fax at by at tkoltt-cbl@cedd.gov.hk For enquiry, please feel free to call For further details, please visit our project website: 7