Environmental Impact Assessment Report
Mott Connell Ltd
40th floor, Hopewell Centre
183 Queen’s Road East
Tel: 2828 5757
Fax: 2827 1823
List of Tables
List of Figures
Figure 2.4 Bottom Pull Method
Figure 2.5 Lay Barge Method
Figure 2.6 Float and Sink Method
Figure 2.7 Horizontal Directional Drilling (HDD) Method
List of Appendices
Appendix D Not Used
Appendix G Not Used
In February 2006, Mott Connell Limited (MCL) was commissioned by Water Supplies Department under Agreement No. CE 42/2005(WS) to carry out the investigation and preliminary design for the “Laying of Western Cross Harbour Main and Associated Land Mains from West Kowloon to Sai Ying Pun” (The Project).
The need for the
project has evolved from the requirement to provide security of water supply
pipelines are strategically important, it is necessary to lay a new
cross-harbour pipeline on the western part of the harbour for maintaining the
reliability of cross-harbour water transfer to
The primary objective of this Assignment is to study the feasibility of providing laying of this additional submarine watermain and associated land mains. The Project and the Environmental Impact Assessment (EIA) is charged with identifying alternative sites and alignments if necessary as part of the EIA study for the Project, and obtaining an Environmental Permit (EP). This Assignment requires preliminary designs, contract strategy, programmes and cost estimates to be prepared to enable the detailed design to proceed. This Environmental Impact Assessment (EIA) Report is a key milestone of the Assignment and has been prepared in conjunction with other design teams.
The route of the proposed watermains is shown in Figure 1.1. The proposed Project is to construct and operate a new western cross harbour main and associated land mains.
The scope of the proposed Project comprises the following:
(i) approximately 2100-metre section of 1200mm nominal diameter of submarine watermain across Victoria Harbour from its connection at Lin Cheung Road in West Kowloon to the existing Sai Ying Pun Fresh Water Pumping Station in Sheung Wan (a designated project under EIA Ordinance);
(ii) approximately 2200-metre section of 1200mm nominal diameter of associated land watermains (Not a designated project under EIA Ordinance).
The submarine watermain component (referred in Section 1.1(i) above) of
the Project is a Designated Project under Schedule 2, Part 1(E3) of the
Environmental Impact Assessment Ordinance (EIAO) (Cap. 499) and an
Environmental Permit (EP) issued under the EIAO is required for the
construction and operation of the designated project. An application
(No. ESB-132/2005) for a EIA study brief under section 5(7)(a) of the EIAO was
submitted by Water Supplies Department on
The purpose of the EIA study is to provide information on the nature and extent of environmental impacts arising from the construction of the proposed designated project and related activities taking place concurrently, ultimately providing information on the following:
(i) the overall acceptability of any adverse environmental consequences that are likely to arise as a result of the proposed project;
(ii) the conditions and requirements for the detailed design, construction and operation of the proposed project to mitigate against adverse environmental consequences wherever practicable; and
(iii) the acceptability of residual impacts after the proposed mitigation measures are implemented.
The scope of the EIA covers the Project proposed in the Project Profile and the works and facilities mentioned in Section 1.1 above. The EIA study addresses the key issues described below, together with any other key issues identified during the course of the EIA study and the cumulative environmental impacts of the Project, through interaction or in combination with other existing, committed, and planned and known potential developments in the vicinity of the Project:
(i) the potential water quality and marine ecology impacts arising from the dredging, laying of pipe and backfilling works for the construction of the submarine watermain.
(ii) the potential noise and dust impacts arising from the construction works of the Project.
(iii) the potential impacts on sites of cultural heritage of marine archaeological deposit likely to be affected by the construction works of the Project.
(iv) the potential fisheries impact arising from the Project.
The EIA study addressed all environmental aspects of the activities and has been based on the best and latest information available during the course of the EIA study. The cumulative environmental impacts from the Project with other interacting projects were assessed, including details of the construction programme and methodologies.
Previously approved studies or EIA reports which are relevant to the Project were reviewed and relevant information extracted for the purpose of this EIA study. The following study or EIA report has been referred to:
Proposed Submarine Gas Pipelines from Cheng Tou
Jiao Liquefied Natural Gas Production Plant,
The proposed Project covers three main areas, namely:
The works for
The works in
In Sai Ying Pun (Not
a designated project under EIA Ordinance), the works comprise Sai Ying
Pun area adjacent to Western Wholesale Food Market and is bounded by the
approaches of Western Harbour Crossing Interchange. The proposed 1200mm diameter fresh watermain
will be laid in this portion for connection to the existing Sai Ying Pun Fresh
Water Pumping Station situated at the junction of
This EIA report covers the designated project component of the Project.
1.4 Environmental Impact Assessment Ordinance
As detailed in Section 1.2, the proposed submarine watermain is a Designated Project under Schedule 2, Part1(E3) of the EIAO (Cap. 499) and an EP issued under the EIAO is required for the construction and operation of the designated project.
To apply for an EP, an EIA must be undertaken in accordance with the requirements of the Study Brief issued by EPD on 13 October 2005, under reference No. ESB-132/2005. Reference can be made to the full requirements of the Study Brief which is contained in Appendix A.
The EIA has been conducted in accordance with the Study Brief, the Project Profile (No. PP-258/2005) and the criteria in the relevant sections of the Technical Memorandum on the EIA Process (Environmental Impact Assessment Ordinance) (EIAO-TM). The EIA has identified, described, predicted and evaluated potential environmental impacts, mitigation measures and will consider the impacts of any feasible alternatives.
The EIA Study assessed and discussed the alternative alignments and landing points of the proposed submarine watermain, alternative construction methods and sequences, and to compare their environmental benefits and dis-benefits with the view of selecting the preferred options from the environmental perspective.
The objectives of the EIA Study as detailed in the EIA Study Brief are as follows:
(i) to describe the Project and associated works together with the requirements for carrying out the Project;
(ii) to identify if there are other types of Designated Projects under Part I Schedule 2 of the EIAO to be covered in the Project;
(iii) to consider alternative alignment(s) and landing points of the submarine watermain, alternative construction method(s) and sequence(s), and to compare their environmental benefits and dis-benefits with the view of selecting the preferred options from the environmental perspective;
(iv) to identify and describe the elements of the community and environment likely to be affected by the proposed project and/or likely to cause adverse impacts to the proposed project, including both the natural and man-made environment;
(v) to identify and quantify emission sources and determine the significance of impacts on sensitive receivers and potential affected uses;
(vi) to identify and quantify any potential losses or damage to flora, fauna and natural habitats and to propose measures to mitigate these impacts;
(vii) to identify any negative impacts on fisheries and to propose measures to mitigate these impacts;