1. INTRODUCTION

1.1 Project Background

1.1.1. The Drainage Master Plan Studies for the Yuen Long, Kam Tin, Ngau Tam Mei and Tin Shui Wai Drainage Basin (YLDMP) were completed in 1998. The majority of the improvement works in Yuen Long and Kam Tin recommended under the YLDMP Study have been completed. Since completion of the DMP Studies, there were changes in developments within the areas and new development proposals and town planning studies were commissioned. In addition, some new flooding complaints were received on the upstream areas of the drainage basins, indicating that further improvement to the drainage systems was required.

1.1.2. DSD commissioned the "Review of Drainage Master Plans in Yuen Long and North Districts - Feasibility Study" (DMP Review Study) in 2008 so that the new development scenarios could be incorporated and the effectiveness of the previously recommended works could also be assessed. The DMP Review Study completed in end 2011 identified that some areas in Yuen Long District could not meet the required flood protection level according to the latest land use changes and future developments taking into account various factors, including sedimentation at the downstream main channels, mangrove growth at river estuaries, updated extreme sea level statistics at Tsim Bei Tsui and projected Climate Change impacts, in the hydraulic analysis. To account for the severity and extent of possible flooding and the works implementation time, the DMP Review Study proposed drainage improvement works in Yuen Long District.

1.1.3. Atkins China Ltd (ACL) was commissioned by Drainage Services Department (DSD) in November 2013 to undertake an Investigation, Design and Construction Consultancy entitled "Agreement No. CE 22/2013 (DS) Drainage Improvement Works in Yuen Long, Stage 1 - Investigation, Design and Construction (hereinafter called the Assignment). The Project comprises construction of drainage improvement works to four villages (namely Sung Shan New Village, Tai Wo, Lin Fa Tei, and Ha Che) including landscaping, waterscaping, utilities diversion, temporary traffic arrangements and any other works incidental to the completion of the Project.

1.1.4. The Assignment is to carry out adoptive review, surveys, investigations, option appraisals, impact assessments, public consultation, planning submissions, architectural, landscaping and greening design, preliminary design, detailed design, tendering, construction supervision and commissioning of the Project as described in the Brief. Construction of the Project is tentatively scheduled to commence in 2022 with a view to completing all the proposed works in 2025.

1.1.5. Since the completion of the DMP Review Study, the Project Management Division of DSD carried out a further review on the proposed works under the Project. The Project was considered feasible to improve the existing drainage condition in Yuen Long for four villages, yet technical concern and public aspirations were also identified that needed to be addressed properly.

1.1.6. The proposed drainage improvement works for consideration under this Report is based on the preferred options evaluated under the Option Exploration and Selection Report for this Assignment.

1.1.7. The Project with Project Profile (No. PP-515/2014) (hereinafter referred as the "Project Profile") allocated with Environmental Impact Assessment (EIA) Study Brief No. ESB-279/2014 for the Project.

1.1.8. The Project is a designated project under Item I.1(b) of Part I, Schedule 2 the EIAO, i.e. A drainage channel or river training and diversion works which discharges or discharge into an area which is less than 300m from the nearest boundary of an existing or planned (i) site of special scientific interest; (ii) site of cultural heritage; (iii) marine park or marine reserve; (iv) fish culture zone; (v) wild animal protection area; (vi) coastal protection area; or (vii) conservation area.

1.2 Objectives of this Report

1.2.1. The objectives of the EIA study are as follows:

· to describe the Project and associated works together with the requirements and environmental benefits for carrying out the Project;

· to identify and describe the elements of the community and environment likely to be affected by the Project and/or likely to cause adverse impacts to the Project, including both the natural and man-made environment and the associated environmental constraints;

· to identify and quantify emission sources and determine the significance of impacts on sensitive receivers and potential affected uses;

· to identify and quantify any potential losses or damage to flora, fauna and wildlife habitats;

· to identify any negative impacts on sites of cultural heritage and to propose measures to mitigate these impacts;

· to identify and evaluate any potential landscape and visual impacts and to propose measures to mitigate these impacts;

· to propose the provision of infrastructure or mitigation measures to minimise pollution, environmental disturbance and nuisance during the construction and operation of the Project;

· to investigate the feasibility, effectiveness and implications of the proposed mitigation measures;

· to identify, predict and evaluate the residual (i.e. after practicable mitigation) environmental impacts and the cumulative effects expected to arise during the construction and operation phases of the Project in relation to the sensitive receivers and potentially affected uses;

· 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 residual environmental impacts and cumulative effects and reduce them to acceptable levels;

· to design and specify environmental monitoring and audit requirements; and

· to identify any additional studies necessary to implement the mitigation measures or monitoring and proposals recommended in the EIA report.

1.3 Structure of the Report

1.3.1. The backgrounds, descriptions and justifications of this Project are provided in Section 2. The assessment results and recommended mitigation measures for each of the environmental parameters that have been identified are presented in the following sections:

Section 3 – Air Quality

Section 4 – Noise

Section 5 – Ecology

Section 6 – Water Quality

Section 7 – Waste Management Implication

Section 8 – Land Contamination

Section 9 – Landscape & Visual

Section 10 – Cultural Heritage

Section 11 – Environmental Monitoring and Audit Requirements

Section 12 – Implementation Schedule of Recommended Mitigation Measures

Section 13 – Summary of Environmental Outcomes and Overall Conclusions