1 Introduction

1.1 Project Background

Shenzhen River is the boundary river between the Hong Kong Special Administration Region (HKSAR) and the Shenzhen Special Economic Zone. In order to prevent serious flooding in the vicinity and improve the livelihood of residents on both sides, the government of the HKSAR and the Shenzhen Municipal Government have jointly completed the Shenzhen River Regulation Program Stages 1, 2 & 3 between 1997 and 2006. About 13.67 km in length of Shenzhen River, starting from the confluence with Ping Yuen River to the river mouth, has been regulated under the first three stages of regulation program.

The purpose of the proposed Stage 4 regulation program is to upgrade the flood protection standard of the Shenzhen River. In addition, the regulation program will also tie in with the development of the proposed Liantang / Heung Yuen Wai (LT/HYW) Boundary Control Point (BCP). The proposed Stage 4 of the regulation program will continue the works of Stage 3 regulation program starting from the Ping Yuen River to about 1.4 km upstream of the proposed LT/HYW BCP (a total of about 4.5 km of Shenzhen River will be regulated) (hereafter “the Project”). In addition, associated with the river training works, the existing boundary patrol road and boundary fence of about 4.5 km in length running alongside the concerned river section are required to be realigned. The location and alignment of the Project Site is shown on Figure 1.1.

Changjiang Water Resources Protection Institute (CWRPI 長江水資源保護科學研究所) in association with ERM-Hong Kong Ltd was jointly commissioned by the Shenzhen River Regulation Office of the Shenzhen Municipal Government (深圳市治理深圳河辦公室) and the Drainage Services Department of the HKSAR to undertake the Regulation of Shenzhen River Stage 4 EIA Study (the Assignment). While the EIA Study has addressed both the Hong Kong EIA requirements and the Shenzhen EIA requirements, this EIA Report (Hong Kong side) only summarizes the findings of the EIA related to the requirements of the Hong Kong side associated with the construction and operation of the Project.

1.2 Need of the Project

The catchment of the Shenzhen River comprises a “fan-shaped” system, characterised by short and steep upstream rivers. Large flow from these rivers can converge into Shenzhen River within a short time. During heavy rain storm, the flood peak can reach the downstream section of Shenzhen River within a few hours. The flooding risk of the Shenzhen River is particularly prominent at times of heavy rain associated with typhoon, where the high sea level suppressed the water discharge from Shenzhen River. Prior to the regulation of Shenzhen River, frequent flooding occurred along the river. Since the completion of the Stage 3 regulation works, the flood prevention ability of Shenzhen River is enhanced and the flooding frequency is reduced.

The section of the Shenzhen River to be regulated under this Project is relatively flat, narrow and winding. The width of the river is uneven and erosion can be found along the river bed and river banks. Some sections of the river embankment have collapsed. The current flood prevention performance are in the range of 1 in 2 to 1 in 20 years, which cannot meet the standard in the PRC National Standard (1 in 20 to 50 years) or the Hong Kong Standard (1 in 50 years).

Figure 1.2 shows the predicted flood extent of a 1 in 50 years flood event. As shown in Figure 1.2, the extent of the flood will encroach into the villages along Shenzhen River, including Ta Kwu Ling Village, Kaw Liu Village, Chuk Yuen Village, Tsung Yuen Ha Village, as well as the boundary patrol road and part of the Lin Ma Hang Road. Hence, there is a need to carry out the Project to rectify the flood prevention performance of this section of the Shenzhen River and to safeguard the livelihood of settlements and boundary security along the river. In addition, the Project will be required to meet the required flood protection standard for the proposed LT/HYW BCP development.

1.3 Existing Environment

Shenzhen River is the drainage outlets of various watercourses in Shenzhen and Hong Kong.  The main tributaries on Shenzhen side include Wu Tong Shan Stream (梧桐山溝), Jing Du Stream (徑肚溝), Chang Ling Stream (長嶺溝) and He Jiao Long Stream (禾叫壟溝) and on Hong Kong side include Ping Yuen River (River Ganges) and Kong Yiu Drainage Channel.

On Hong Kong side, the Project Site is located at rural area entirely within the Frontier Closed Area in the New Territories. The surrounding environment consists of mainly abandoned agricultural fields and scattered rural village houses.

1.4 Objectives of the EIA Study

The Project is classified as a Designated Project under Item I.1, Part 1, Schedule 2 of the EIA Ordinance and therefore the construction and operation of the Project will require an Environmental Permit. The overall objectives of the EIA Study are to provide information on the nature and extent of environmental impacts arising from the Project; to recommend appropriate mitigation measures to control the potential environmental impacts so that it complies with the requirements of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM); and to confirm the environmental acceptability of the Project.

The specific objectives of the EIA Study described in the EIA Study Brief No. ESB-200/2009 are listed below:

(i) to describe the Project together with the requirements for carrying out the Project;

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

(iii) to provide information on the consideration of alternatives (such as various construction and dredging methods and mitigation measures) with a view to avoiding or minimizing the potential adverse environmental impacts to environmentally sensitive areas and other sensitive uses; to compare the environmental benefits and dis-benefits of each of different options; to provide reasons, justifications and constraints for selecting the preferred option(s); and to describe the part environmental factors played in the selection of preferred option(s)

(iv) to identify and quantify emission sources and determine the significance of impacts on sensitive receivers and affected uses with respect to air quality, noise, water quality, waste management implication, land contamination, terrestrial and aquatic ecology, fisheries impacts, landscape and visual, and sites of cultural heritage;

(v) to identify and quantify any potential loss or damage to flora, fauna and natural habitats;

(vi) to identify and quantify any potential fisheries impacts arising from the construction and operation of the project and to propose measures to avoid in the first instance or mitigate these impacts if the project would affect any active or inactive fishponds;

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

(viii) to identify and quantify contaminated land within any project area for development works, and to propose measures to avoid disposal in the first instance;

(ix) to identify any potential landscape and visual impacts and to propose measures to mitigate these impacts;

(x) to propose measures to avoid or the provision of infrastructures or mitigation measures to minimize pollution, environmental disturbance and nuisance during construction and operation of the Project and associated works;

(xi) to investigate the feasibility, practicability, effectiveness and implications of the proposed mitigation measures;

(xii) to identify, predict and evaluate the residual environmental impacts (i.e. after practicable mitigation) and the cumulative effects from other projects within the assessment area, including those within Shenzhen area, expected to arise during the construction and operation of the Project in relation to the sensitive receivers and potentially affected uses;

(xiii) 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 reduce them to acceptable levels;

(xiv) to investigate the extent of the secondary environmental impacts that may arise from the proposed mitigation measures and to identify constraints associated with the mitigation measures recommended in the EIA study, as well as the provision of any necessary modification;

(xv) to design and specify environmental monitoring and audit requirements to check the effective implementation of the recommended environmental protection and pollution control measures; and

(xvi) to identify individual project(s) and associated works of the Project that fall under Schedule 2 of the EIAO; to ascertain whether the findings of this EIA study have adequately addressed the environmental impacts of the identified EIAO Schedule 2 designated projects; and, where necessary, to identify the outstanding issues that need to be addressed in any further detailed EIA study.

1.5 Organisation of the Report

The remainder of this report is organised as follows:

· Section 2 presents a description of the alternatives considered for the design and construction of the Project;

· Section 3 presents a description of the Project;

· Section 4 presents the air quality assessment;

· Section 5 presents the noise assessment;

· Section 6 presents the water quality assessment;

· Section 7 presents the ecological assessment;

· Section 8 presents the fisheries assessment;

· Section 9 presents the waste management implication;

· Section 10 presents the land contamination assessment;

· Section 11 presents the cultural heritage assessment;

· Section 12 presents the landscape and visual assessment;

· Section 13 describe the requirements for environmental monitoring and audit; and

· Section 14 summarises the environmental outcomes associated with the Project.